DifferentialDiagnosisInPrimaryCare 4thEdition

8/14/2019 DifferentialDiagnosisInPrimaryCare 4thEdition

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Authors: Collins, R. Douglas

Title: Differential Diagnosis in Primary Care, 4th Edition

Copyright 2008 L ipp incott Wi l l iams & Wi lkins

> Table of Contents > P > Pallor of the Face, Nail s, or Conjunct ivaPallor

of the Face, Nails, or Conjunctiva

Pa llor i s a lmost i nvariab ly caused by anemia and i s best analyzed

wi th the app li cat ion o f pathophysiology. Anemia may be caused by

decreased product ion of b lood, increased destruct ion of b lood, or

loss o f blood. Decreased production resul ts from poor nutri t ion

part icularly, poor absorpt ion or intake of B 12 (pernicious anemia),

iron (iron def iciency anemia), and fol ic acid (malabsorption

syndrome). It may a lso resul t from suppressed bone marrow

(aplast ic anemia) or inf il t rated bone marrow ( leukemia or

metastat ic carcinoma). Increased destruction is caused by

hemolys is from int rins ic defects i n the red ce ll s (e.g. , s i ckle cel l

anemia and thalassemia) or extrinsic defects in the c i rculation

(autoimmune hemolyt ic anemia of many d isorders). Blood loss may

result f rom pept ic ulcers and carc inomas of the gastrointest inal(GI) tract, excessive menstruation or metrorrhagia f rom tumors of

the uterus, or dysfunct ional uterine b leeding. These are the

principal causes of anemia, but t he reader wi ll be able t o t hink of

several more. What i s important here i s t o have a sys temat ic

method to recal l them.

If anemia i s ruled out , t he l ess frequent causes of pal lor should be

considered. Shock, congestive heart fai lure (CHF), andarteriosclerosis cause pal lor by poor c irculat ion of b lood to the

skin. Pa tients who have hypertension may be pale from re flex

vasomotor spasms of the arterioles supplying the skin. Aortic

regurgi tat ion and s tenos is, as wel l as mit ral s tenos is, cause pa llor

for t he same reasons , but t he malar fl ush of mi t ral s tenos is may

negate this. The reason that tuberculosis, rheumatoid arthri t is,

carcinomatosis, and g lomerulonephrit is cause pal lor even when

the ir vi ct ims a re not anemic or hypertensive i s not known.

Approach to the Diagnosis

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The approach to the d iagnos is o f pal lor i s obviously to check for

anemia f irs t ; then to examine for the other chronic di sorders. Chest

x-ray, e lectrocardiogram (ECG), sedimentation rate, and a check for

rheumatoid factor are al l appropriate in speci f ic cases.

Other Useful TestsComplete b lood count (CBC) (anemia)

Sedimentation rate (chronic infection)

Chemistry panel (anemia of l iver and k idney d isease)

Serum B12 l evel (pernicious anemia)

Serum fol ic ac id level ( fo lic acid def iciency)

Serum i ron and ferri t in levels ( iron def iciency anemia)

Stool for occul t b lood (GI b leeding)Stoo l for ova and paras i tes (anemia due to paras i te

infestation)

Serum haptoglobins (hemolytic anemia)

Antinuclear ant ibody (ANA) analysis (collagen d isease)

Bone marrow examination (aplast ic anemia)



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> Table of Contents > P > Palpitat ionsPalpitations

Because anxiety i s the common cause o f palpi tat ions, there i s a

t remendous temptat ion to jump to this conclus ion as the cause in

an otherwise hea lthy-looking individual . If we use the mnemonic

VINDICATE, we may avoid a mi sdiagnos is in many cases .

VVascular causes help to recal l aort i c aneurysms,

arter io venous f istulas, anemia, postural hypotension,

migraine, and cardiac d isorders such as aort ic

regurgitation, aortic stenosis, tricuspid insufficiency,

CHF, and var ious arrhythmias (see page 77).

IInflammation reminds us o f fever, per icardi t is,

subacute bacterial endocardit is (SBE), and rheumatic

fever.

NNeoplasms are not usual ly associated wi th

palpitations.

DDeficiency of t hi amine can l ead t o beriberi heartdisease resul t ing in pa lpi tat ions.

IIntoxication prompts us t o recal l that al cohol ,

tobacco, cof fee, sof t drinks, and tea can cause

palpi tat ions. I t should a lso remind us that palpi tat ions

are common s ide e ffects of many drugs, including

digital is, aminophyll ine, sympathomimetics, ganglionic

blocking agents, n it rates, and other drugs.CCongenital d isorders that may cause palpi tations

include patent ductus, ventricular septa l defect, and

hiatal hernia.

AAnxiety is a common cause of palpi tat ions .

TTrauma causes pa lpi tat ions by inducing the

release of epinephrine, but there i s no diagnost ic

di lemma in these cases.

EEndocrine d isorders that cause palpi tat ions include

thyrotoxicosis , pheochromocytoma, menopausal



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syndrome, and hypoglycemia.

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Pallor of the face nails or con unctiva



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Valvular heart d isease, anemia, and febri le d isorders wil l usual ly be

revealed on physical examinat ion. I t i s important to inquire about

drug, al cohol , and tobacco use. Caf fe ine i s a frequent o ffender . I t

i s helpful to e liminate any suspicious med icat ions i f poss ible. A

drug screen may be usefu l i n many cases. The ini t ia l diagnost ic

workup should include a CBC, chemistry profi le, thyroid profi le,

sedimentat ion rate, ant i -streptolysin O (ASO) t i ter , ECG, and chest

x-ray. I f these have normal f indings, 24-hour Hol ter monitoring or

continuous loop event recording of the ECG should be undertaken.

P.341



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Pal itation



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Other Useful Tests

24-hour urine catecholamine or vani l lylmandel ic acid

(VMA) (pheochromocytoma)

Arm-to-tongue circulation t ime (CHF)

Echocardiography (CHF, valvular heart disease)

Exercise tolerance test (coronary insufficiency)

Upper GI series and esophagram (hiata l hernia)

24-hour blood pressure monitoring (pheochromocytoma)

Psychometric testing (hysteria)

P.342

Case Presentation #71

A 62-year-old physician complained of f requently awakening at

night w ith palpi tat ions . It would t ake him at l east an hour t o go

back t o s leep. He al so had t o uri nate a t lea st twi ce at ni ght but

denied daytime frequency o f urination. He denied the use o f

al cohol , t obacco, or drugs but usual ly has a cup of cof fee i n t he

morning and a coke at l unch.

Question #1. Utilizing your knowledge of physiology and the

mnemonic VINDICATE, what is your differential diagnosis?

Physical examination was unremarkable. His blood pressure was

110/70 mm Hg, and his pulse was 66 bpm. Results of laboratory

studies and an exercise tolerance test were normal.

View Answer

HyperthyroidismEarly congestive heart fa ilure

Pheochromocytoma

Chronic anxiety neurosis

Fever o f unknown origin

Coronary insufficiency

Hiata l hernia and esophagit is

Question #2. What is your diagnosis now?View Answer




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Substance abuse

Caffeine intolerance

Final Diagnosis: Caf fe ine into lerance (A ll h is symptoms subsided

upon the e limination o f caffeine from h is d ie t.)



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> Table o f Contents > P > Papi lledemaPapilledema

No anatomic analys is o f thi s condi t ion i s necessary because most

cases o f papi lledema are caused by intracranial pathology. Three

notable extracranial condit ions are opt ic neurit is, hypertension, and

pseudotumor cerebri . The polycythemia and r ight heart fai lure o f

chronic pulmonary emphysema may combine to produce

papil ledema, but this i s uncommon. Analysis o f the intracrania l

causes of papi lledema is performed using the mnemonic

VINDICATE.

VVascular l es ions are aneurysms and arteriovenous

malformations that cause subarachnoid hemorrhages.

Severe hypertension may lead to an intracerebral

hemorrhage or hypertensive encephalopathy, thus

causing papi l ledema. Cerebral thrombosis and embol i

rarely lead to papil ledema.

IInfection i s not a common cause o f papi lledemaunless a space-occupying les ion i s produced or the

condi t ion pers ists . Thus, a bra in abscess i s o ften

associated with papil ledema, whereas acute bacteria l

meningitis is not. Chronic cryptococcal meningit is,

syphi l i t ic meningit is, and tuberculous meningit is, in

contrast , a re o ften associated wi th some degree o f

papi lledema. Viral encephal it is may occasional ly beassociated with papil ledema. Cavernous s inus

thrombosis and sept ic thrombosis o f the other venous

sinuses may produce papi lledema.

NNeoplasms, primary and metastat i c, are the most

common cause of papi l ledema.

DDegenerative di seases are ra rely the cause.

IIntoxication brings to mind lead encephalopathy,

but other tox ins and drugs rarely cause papil ledema.

CCongenital mal format ions that cause papil ledema



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include the aneurysms and arter iovenous malformations

a lready mentioned plus the various types o f

hydrocephalus, skull deformities (oxycephaly),

hemophi l ia (because of intracranial hemorrhages), and,

occasional ly, Schi lder d isease and other congenitalencephalopathies.

AAutoimmune d i sorders reca ll lupus cerebri t is and

periarter itis nodosa (when associated with severe

hypertension).

TTrauma does not usua lly produce papi l ledema in

the early s tages o f concuss ions or epidural or subdural

hematomas, but i n chronic subdural hematomas i t i s the

rule.

EEndocrine di sorders bring to mind the papi lledema

of malignant pheochromocytomas (with hypertension)

and the fact that pseudotumor cerebri occurs in obese,

amenorrheic, and emotionally disturbed women.


The approach to the d iagnos is o f papi l ledema in someone wi thouthypertension or hypertensive ret inopathy must include a thorough

neurologic examinat ion and a computed tomography (CT) scan. I f

foca l s igns are present or the CT scan shows pos i tive f indings,

referral t o a neurosurgeon i s i ndi cated. He or she can decide if a

magnet ic resonance imaging (MRI) i s i ndicated. A spina l tap i s

contraindicated. I f there are no foca l s igns, i t may be wor thwhi le to

di fferentiate papi lledema f rom opt ic neuri t is by having an

ophthalmologist perform a v isual f ie ld examinat ion. This may a lso

be helpful in d if ferent iat ing pseudotumor cerebri because there may

be b ilatera l vi sua l de fects i n the inferior nasal quadrants.

Papil ledema f rom increased intracranial pressure wil l show only an

en larged bl ind spot (unless t here i s a t umor of t he opt ic t racts,

radiat ions, or occipi tal cortex), whereas opt ic neuri t is wil l show

scotomata per ipheral to the bl ind spot (disc). Appendix A wi l l be

usefu l for confi rming the diagnos is o f a speci fi c di sease.

Other Useful Tests



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CBC (polycythemia)

Sedimentation rate (cerebral abscess, infect ion)

Urinalysis (renal d isease associated with hypertension)

ANA analysis (col lagen d isease)

P.343



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Pa illedemaP.344

Blood l ead l evel

Visual evoked potent ia ls (optic neuri t is)



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Pulmonary function tests (emphysema)

Blood volume (polycythemia vera)

24-hour blood pressure monitoring (hypertension)

Spinal tap when imaging study i s negative (pseudotumor

cerebri)



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> Table of Contents > P > Paresthesias, Dysesthesias, and Numbness

Paresthesias, Dysesthesias, and

Numbness

TABLE 49. Paresthesias, Dysesthesias,

and Numbness

V I N D I C A T EVasc

ular

Infla

mmat

ory

Neo

plas

m

Dege

nerat

ive

Intox

icatio

n

Cong

enital

Autoi

mmun

e

Allergi

c

Trau

ma

Endoc

rine

Perip

heral

Nerv

e

Causalgia

Raynaud disease

Buerger disease

Arteriosclerosis

Ischemic neurit is

Pella

gra

Berib

eri

Nutrit

ional

neuro

pathy

Alcoh

olic

neuro

pathy

Isonia

zid

toxici

ty

Lead

and

arseni

c

neuro

pathy

Porph

yria

Infecti

ous

neuron

itis

Periart

eritis

nodos

a

Trau

ma

Hem

atom

a

Lacer

ation

Neur

oma

Frost

bite

Tetany

of

hypop

arathy

roidis

m

Aldost

eronis

m

Nerv

e

Plex

us

Leriche

syndrome

Pancoast

tumor

Scale

nus

anticu

s

Cervic

al ri b

Infecti

ous

neuron

itis

Cont

usion

Lacer

ation

Fract

ure

Diabet

ic

neurop

athy

Nerve Tabes Meta Herni Spondylol ist Fracture



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Root dorsa

l is

Tuber

culosi

s

stati

c and

prim

ary

tumo

rs of

the

cord

and

spine

(mult

iplemyel

oma

ated

disc

Cervi

cal

and

lumb

ar

spon

dylos

is

hesis Herniated

disc

Spin

al

Cord

Anter

ior

spina

l

arter

y

occlu

sion

Aorti

c

aneur

sm

Polio

myeli

t is

Epidu

ral

absce

ss

Tuber

culosi

s

Syphi

l is

Meta

stati

c and

prim

ary

tumo

rs of

the

cord

and

spine

Spon

dylos

is

Disc

disea

se

Perni

cious

anem

ia

Trans

verse

myelit

is

from

radiat

ion

Spina

bifida

Myelo

cele

Syring

omyel

ia

Guillai

nB

arr

syndro

me

Multipl

e

sclero

sis

Fracture

Herniated

disc

Hematoma

Brain

Cerebral

embo

lus,

thro

mbus

,

hemo

rrhag

Neurosyphil

is

Encep

haliti

s

Brain

absce

ss

Braintumo

r

Senile

deme

ntia

Prese

nile

deme

ntia

Alcoholism

Bromi

sm

Encep

halop

athy

Opiat

es,

Atrioventric

ular

anom

alies

Aneur

ysm

Epilep

sy

Lupuscerebri

t is

Multipl

e

sclero

sis

Depresse

d

fract

ure

Subd

ural

hema

toma

Pituitary

tumor

Acrom

egaly



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e

Carot

id or

basil

ar

arter

y

insuff

icienc

y

Migra

ine

barbit

urate

s,

etc.

Cereb

ral

palsy

Anatomical ly, t ingl ing and numbness or other abnormal sensations

in the extremit ies resul t from involvement o f the peripheral nerve,

the nerve plexus (brachial or sciat i c) , the nerve root , the spina l

cord, or t he brain. When each o f t hese i s cross-indexed w ith t he

et io log ies suggested by the mnemonic VINDICATE, mos t of the

causes can be deve loped (Table 49). Only the most important

condit ions are mentioned in this d iscussion.Peripheral nerve. Per ipheral neuropathies f rom a lcohol,

diabetes, and o ther causes a re important i n thi s

category, but one should not forget vascular diseases

that may cause paresthesias, such as peripheral

arteriosclerosis, Raynaud syndrome, and Buerger

disease. In addi t ion, metabol ic disorders such as tetany

and uremia should be considered. Chronic acute

inflammatory demyelinating polyneuropathy

(Guil la inBarr syndrome) is brought to mind here.

Fina lly, nerve entrapments such as carpal tunnel

syndrome need to be checked.

Nerve plexus. The brachia l plexus may be involved by

the scalenus ant icus syndrome, a cervical rib, or

Pancoast tumor. The sciat ic plexus may be compressed

by pelvic tumors.

Nerve root. Herniated d isks, spondylosis, tabes



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dorsal is, and inf il t rat ion of the spine by tuberculosis,

metastat i c tumor, and mul tiple myeloma need to be

remembered here.

Spinal cord. Spina l cord tumors, pernicious anemia, and

tabes dorsal i s a re the most important condi t ions torecall here.

Brain. T ransient i schemic at tacks (TIAs), emboli , and

migraines are vascular diseases to remember in addi t ion

to the di seases that affec t t he spinal

P.345

cord. The aura o f epi lepsy i s a lso important. One would not

want to miss brain tumors, abscesses, and toxic

encephalopathy because these are potentia l ly t reatable.


This would be t he s ame as t he workup of weakness in one or more

extremi ti es . If t he condi ti on i s i n t he hand, one would check for

Tine l and Adson s igns and x-ray the cervical spine for a cervical ribor disk degenerat ion. The next s teps are nerve conduct ion studies

and Electromyogram (EMG). Object ive s igns of radiculopathy are a

clear indicat ion for an MRI or cervical myelography, preferably

combined w ith a CT scan. MRI may reveal t iny di sk herniat ions.

Wi th associated pain in certain roots, diagnost ic nerve blocks may

be i ndi cated. If t here i s coldness in t he hand, a s te ll ate gangl ion

block may be helpful.

I f the condi t ion i s i n the l ower ext remity, a carefu l examination o f

the arterial pulses, part icularly the femoral , i s performed. I f these

are abnormal , a f low s tudy or femoral angiography may be

indi cated. X-rays of t he spine t o rule out a herniated di sk or t umor

o f t he spine are done rout ine ly. One must not forget a pe lvi c

examination in a female. I f o ther neurologic s igns are present, an

MRI or CT s can may be necessary. When a di sk herniat ion i s s ti ll

l ike ly, myelography should be ordered. EMG has the sameusefu lness here as i n the upper ext remity. When a cerebra l l es ion



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i s suspected, a CT scan, MRI, and four-vessel angiography should

be considered.

Other Useful Tests

CBC (anemia)

Chemistry panel (hypoparathyroidism, electrolyte

disturbance, uremia)

Fluorescent treponemal antibody absorption (FTA-ABS)

test (neurosyphil is)

Serum B12 and fol i c acid l evels (pernicious anemia)

Schi l l ing test (pernicious anemia)

Blood lead level ( lead neuropathy)

ANA analysis (col lagen d isease)Glucose tolerance test (diabetic neuropathy)

Urine porphobilinogen (porphyria)

Hair analysis for a rsenic

P.346



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Paresthesias d sethesias and numbness

P.347



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Paresthesias d sethesias and numbness

P.348

Paresthesias, dysethesias, and numbness

Somatosensory evoked potentia ls (multip le sclerosis)

Spinal tap (neurosyphil is, mult iple sclerosis)

Anticentromere antibody (scleroderma)


A 25-year-old white male intern compla ined of intermittent



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numbness and t ingl ing for several months o f the lower extremit ies

and, to a l esser extent, the upper ext remit ies. He had occas iona l

weakness i n hi s l ef t arm and hand but was t old on an i nsurance

examination that that was due to a scalenus ant i cus syndrome. He

denies a lcohol or substance abuse.Question #1. Utilizing your knowledge of neuroanatomy, what is

your differential diagnosis?

Further history reveals that he had an episode of optic neuritis

at age 17. His neurologic examination reveals hyperactive

reflexes of the left upper and lower extremities but is otherwise

unremarkable.

View Answer

Peripheral neuropathy

Tumor of the cervical spina l cord

Pernicious anemia

Multiple sclerosis

Basilar artery insufficiency

Parasagittal meningioma

Brainstem gl ioma

HypoparathyroidismNeurosyphilis

Col lagen d isease

Hyperventilation syndrome

Question #2. What is your diagnosis now?

View Answer

Multiple sclerosis

Final Diagnosis: Mul ti ple s cl eros is was con fi rmed by MRI of t hecervical spine.



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> Table of Con tents > P > Pelvic MassPelvic Mass

Pelvic mass

A mass in t he pel vi s i s usual ly (but not always) a neoplasm. Is

there a quick way to recal l a ll the various causes while examining

the pelvis? Anatomy is the key. Apply t he mnemonic MINT to

develop a l is t of the many poss ibi l it ies (Tab le 50).

Anatomical ly, there are three major groups of s t ructures: the

urinary t ract , the female geni tal t ract , and the l ower intest ina l

tract. Breaking these down into their components, there are the

bladder and ureters; the vagina, cervix, uterus, fal lop ian tubes, and

ovaries; and the rectum and s igmoid colon. In addi tion to these

structures, the d iseases o f the aorta and i li ac vessels , spine, and

surrounding muscles and fascia must be considered. Other

structures f il l the pelvis f rom above. The smal l i ntest ines, the

omentum, and the appendix may be fel t ; even the kidney may dropinto the pelvis .



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Bladder. P rominent condit ions that must be considered

here are stones, d ivert icula, Hunner u lcer, and

carcinomas. A distended b ladder i s decept ive.

Urethra. A cystocele and urethrocele a re fe lt eas ily

during a pelvic examination, but i f they a re not , havethe pat ient s t rain or s tand up.

Ureters. A u retera l calculus or ureterocele may be fel t .

Vagina. Vaginal carcinomas, prolapsed cervix or

procident ia, rectocele, and Barthol in cysts may be fel t . A

foreign body (e.g., a pessary) should be considered.

Cervix. Carcinoma or po lyps are the main considerat ions

here, because an inflamed cervix does not usual ly cause

a mass.

Uterus. Fi broids are t he most l ikely t umor t o be f el t,

but pregnancy, chronic endometrit is, choriocarcinoma,

and endometrial carcinomas a ll present as a mass. A

ret roverted uterus may masquerade as a mass in the

cul-de-sac.

Fallopian tubes. Tubo-ovarian abscesses and

endometriosis o f these structures account for mostcases. Ectopic pregnancy i s a lways possible.

Ovary. Ovarian cysts and carcinomas must be

considered as wel l as endometriosis.

Rectum. Carcinoma, abscesses, d ivert icula, and

prolapse are good possibi l i ties here. Feces may

masquerade as a mass.

Sigmoid colon. Aga in, the d isorders ment ioned in thesect ion on the rectum (see page 385) must be

considered. Granulomatous or ulcerat ive col i t is may

present as a mass .

P.350



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TABLE 50. Pelvic Mass

Anatom

M I N TMalforma

tion

Inflammat

ion Neo lasms TraumaBladder Obstructio

n wi th

diverticul

um

Calculi

Hunner

ulcer

Carcinoma

Polyp

Rupture

o f t he

bladder

Urethra Urethrocele

Cystocele

Double ureter

Calculus

Ureterocele

Ureters Papilloma

Vagina Prolapsed

cervix

Rectocele

Bartholinit

i s f is tula

with

rectum or

bladder

Carcinoma Foreign

body

Tear

Cervix Cervicitis

rarel

Carcinoma

PolUterus Bicornuat

e uterus

Retroversi

on

Endometrit

is

Endometrial

carcinoma

Choriocarcino

ma

Fibroid

Rupture

during

pregnan

cy

Fallopian

Tubes

Ectopic

pregnancy

Endometri

osis

Salpingitis Carcinoma

(rarely)

Ovary Benign

congenital

ovarian

cyst (e.g.,

Morgagni)

Oophoritis Cystadenoma

Cystadenocar

cinoma

Foll icular and

granulosa

cel l c st



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Rectum Prolapse

Rectocele

Inflamed

hemorrhoi

d

Rectal

abscess

Fistula

Rectal

carcinoma

Sigmoid Diverticul

um

Diverticuli

t is

Granuloma

tous

colitis

Ulcerativecolitis

Carcinoma of

polyp

Foreign

body

rteries Aneur smSpine Lordosis

Scoliosis

Rheumatoi

d arthrit is

Spondylosi

s

Tuberculos

is

Metastatic

carcinoma

Myeloma

Hodgkin

lymphoma

Fracture

Rupture

d dis c

Miscellane

ous

Pelvic

kidney

Omental

cyst and

adhesions

Appendicit

is

Regional

i leit is

Pelvic

metastasis

from

stomach,

e.g.

Blood

clot i n

cul-de-s

ac

Surgical

abscess

P.351

Arteries. It i s unusual for an aort ic or i l iac aneurysm t o

be f el t here, but they should be kept i n mind.

Spine. Deformit ies o f the spine (e.g. , l ordos is),

tuberculosis (Pott d isease), and metastat ic or primary

mal ignancies o f the spine (e.g., myeloma) may present

as a pe lvi c mass .Miscellaneous. A pe lvi c ki dney may be fe lt . An i nfl amed



28/88

segment of i l eum ( regiona l i le it i s) or the append ix

should be considered, as should omenta l cysts and

adhesions.


The associa tion wi th o ther symptoms i s the key to the c lini cal

diagnos is . A painless mass i s l ikely t o be a neop lasm, whereas a

tender mass with fever suggests pelvic inf lammatory disease (PID)

or a d ivert icular abscess. Obviously, an ectopic pregnancy should be

associated with tender breasts, f requency of ur inat ion, and morning

s ickness. The next l og ical s tep i s ul t rasonography and a

gynecologic consult.

Laboratory tests include urinalysis and culture, pregnancy test,stool for blood and parasi tes, and vaginal cul tures. A proctoscopy

and bar ium enema may be useful . Colonoscopy, culdoscopy,

peri toneoscopy, and cystoscopy may al l need to be done before an

exploratory laparotomy is performed.

Other Useful Tests

Sedimentation rate (PID)

Tuberculin test ( tuberculosis o f the fal lop ian tubes)

Catheterizat ion for residual urine

Culdocentesis (ruptured ectopic pregnancy)

Laparoscopy (ectopic pregnancy, neoplasm)

CT scan of the pelvis (neoplasm, stone, d ivert iculum,

abscess)

Aortogram (aortic aneurysm)

Exploratory laparotomyUrology consult

Gynecology consult



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> Table of Con tents > P > Pelvic PainPelvic Pain

Visual iz ing the anatomy of t he pelvi c area i s t he key t o forming a

li st of t he causes of pe lvi c pain. Start ing at t he skin and working

inward, we have the muscles

P.352

and fascia, b ladder, per itoneum, uterus, ovaries, fa l lopian tubes,

intest ines, rectum, and spine. The skin helps to recal l herpes

zoster, the muscle and fascia suggest contus ion and hernia, and

the peri toneum would remind one of per i tonit is and endometriosis.

The uterus, ovary, and tubes would prompt considerat ion of PID,

dysmenorrhea, pelvic congestion, and ectopic pregnancy. Ovarian

tumors can al so cause pe lvic pa in by twisting on the ir pedicle. A

pedunculated uterine fibroid can al so twist on i t s pedicle caus ing

severe pa in. I f the pelvic pa in i s related to the menstrual cycle,

one should recal l mit telschmerz. Consider ing the intestines, oneshould recal l appendicit is and d ivert iculi t is. Considering the rectum

should prompt reca ll of hemorrhoids, f issures, and recta l abscess.

Fina lly, thinking of the spine should suggest rheumatoid

spondyl it is, osteomyel it is, herniated d isk, and other condit ions.



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Pelvic ain


A good pelvic and rectal examination i s essential . These w il l o ften

di sclose a mass or other pathology t o explain t he pain. I f t here i s a

vaginal d ischarge, a smear and cul ture for gonococcus andChlamydia need t o be done. A pregnancy tes t wil l h elp rul e out an

ectopic pregnancy, but ultrasonography is most useful.

A gynecology consul t should be obtained when there i s any doubt .

In acute cases, the gynecologist may proceed with an exploratory

laparotomy immediately.

Other Useful Tests

CBC (PID, ruptured ectopic pregnancy)

Chemistry panel

Urinalysis (cystit is, pyelonephritis)

Urine culture (cyst it is, urinary tract infect ion [UTI])

Pregnancy test (ectopic pregnancy)

CT scan o f abdomen and pelvis (only i f pregnancy has

been ruled out) (neoplasm, abscess)

Culdocentesis (PID, neoplasm, ectopic pregnancy)Laparoscopy (PID, neoplasm, ectopic pregnancy)



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Peritoneal tap (peritonit is, ruptured ectopic pregnancy)



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> Table of Contents > P > Penile PainPenile Pain

Perhaps no other pain wi ll bring a pati ent t o t he doctor more

qui ckly i n t hi s age of sexual candor. Most cases w il l be caused by

inflammation, s o a mnemoni c of et iol ogi es i s, for t he mos t part ,

superf luous. Ut i lization of anatomy i s valuable, however. Le t us

beg in, then, w ith the head of the penis and proceed upward t o t he

prostate, the b ladder, and the k idney.

The head of the penis may be inflamed by a painful chancroid ul cer

or lymphogranuloma venereum, but one must remember that a

chancre (syphi l i t ic ulcer) i s not painful . Herpes progenital is, in

contrast , i s ext remely pa inful . Balan it i s i s usual ly caused by a

nonspeci f ic infect ion, but one should caution the uncircumcised

patient about proper cleaning o f the area and ru le out Rei ter

disease. (Look for conjunct ivi t is and joint symptoms.) Trauma to

the head of t he pen is should be obvious , but some pat ients may be

too shy to mention i ts origin wi thout careful quest ioning.Carcinoma o f the penis rarely causes pa in, but l i ke a ll carcinomas,

it w il l of ten be painful when i t i s secondari ly i nfected.

Next , l et us cons ider the urethra. Inf lammation here i s probably

the most common cause o f peni le pain. I t i s almost i nvariably

associated wi th a d ischarge, and the smear wi l l usua lly di sclose the

typical Gram-negative intracel lular d iplococci of gonorrhea. The

cl inician i s reminded that nonspeci f ic urethri t is i s more frequentlyencountered each year and that Chlamydia and mima polymorpha

are common causes. Rei ter di sease must al so be cons idered.

Passage o f a s tone through the urethra causes pain i n t he pen is .

The shaft of the penis is one of t he few areas i n which a vascul ar

les ion may account for peni le pa in. Thrombosis o f the corpus

cavernosum is often encountered in b lood dyscrasias (part icular ly

leukemia), and the resul t ing permanent erect ion may be enviable

and even humorous to the observer but not to the patient. Peyronie

disease w il l cause a pa inful erection.



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Moving to the prostate, one hardly needs t o be reminded that bo th

acute and chronic prostat i ti s are frequent causes o f peni le pain. In

contrast, carc inoma and hypertrophy of the prostate are rare ly

associated wi th pa in un less there i s associated infection.

The bladder i s another common source o f pen ile pain, but becausethere i s of ten an associated urethri t is , i t i s uncertain whether pure

cyst it i s causes penile pain by i tse lf except on ur ination. B ladder

stones cause pain in the penis , especial ly on urination. Carcinoma

of t he bl adder wi ll not usual ly cause peni le pain unless i t i s

compl icated by infect ion. Hunner u lcer, in contrast, causes great

pa in in the penis at t imes. Occas iona lly, ureteral and renal s tones

wi ll cause penile pa in, but pyelonephri ti s i s very unl ikely to do so.

Referred pain f rom the rectum caused by hemorrhoids and f i ssures

is common.


Finding any l es ion o f the penis should prompt a smear and cul ture

of the exudate or scrapings. A dark fi eld examinat ion wi l l of ten be

indicated by the hi s tory o f sexual

P.353

contact . Any urethral di scharge must a lso be examined a fter a Gram

stain and cul tured for gonococci and Chlamydia. Prostat ic massage

may be necessary to get adequate urethral material . Next , a

urina lys is i s done and a fresh drop i s examined under h igh power

for mot i le bacteria s ignifying cyst i tis or pyelonephr it is. A urine

cul ture and colony count wi ll be w ise i n any case. I f the di agnos is

is s ti ll obscure, i t i s w ise t o consul t a urologi st before proceeding

with an intravenous pyelogram (IVP) or other expensive tests.



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Penile ain

Other Useful Tests

Cystoscopy (stricture, tumor, stone)

Retrograde pyelography (tumor, stone, malformation)

CBC (infection)

Chemistry panel (hypercalcemia, hyperuricemia)

Strain urine for s toneCT scan o f the abdomen and pelvis (tumors, s tones,

malformation)



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> Table of Contents > P > Penile SoresPenile Sores

To recal l t he possible causes of peni le sores , t hink of the smal lest

micro-organism up to the largest.

Virus. Th is brings to mind geni ta l herpes (herpes

simplex v irus 2 [HSV2]). Genita l warts are included here,

but are rare ly di f ficul t to d iagnose.

Bacteria. Th is should faci li tate the recal l of chancro id

(caused by Haemophi lus ducreyi; baci l lus),

lymphogranuloma venereum and granuloma inguinale

(caused by calymmatobacterium granulomatous).

Abscess and ba lani t is should a lso be recal led here.

Spirochete. Th is suggests chancre, t he fi rs t s tage o f

syphilis.

The above c lass i fi cat ion would not help recal l an epi the lioma or

lacerat ion and other les ions caused by t rauma.


Something that i s o ften neglected today i s the t racking down of

contacts which can ass is t i n the d iagnos is. A pa inless l es ion

suggests chancre, whereas a painful les ion i s typical of chancroid,

herpes s implex, or balani t is. The presence of inguina l

lymphadenopathy should a lert the c l inician to lymphogranuloma

venereum, chancre, and epithelioma.

A smear and cul ture should be done i f balani ti s or chancroid i s t he

cl inical diagnos is. A dark f ie ld examination i s done to confi rm the

diagnosis o f chancre. The f inding of intracellular Donovan bodies

wi ll confi rm the d iagnos is o f granuloma inguina le. A Tzanck test

wil l assi st i n t he di agnos is of geni tal herpes but i s not usual ly

necessary. Serologic tests or a G iemsa s tain o f scrapings of the

primary l es ion may be examined for i nclus ion bodies in cases o f

lymphogranuloma venereum. A biopsy i s necessary to d iagnose anepithelioma.



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> Table o f Contents > P > Periorbital and Facial EdemaPeriorbital

and Facial Edema

The mechanism for periorbi tal and facial edema i s s imi lar to that

for edema of the extremit ies. Thus, increased backpressure of the

veins wil l cause per iorbi tal edema in right heart fai lure, constrict ive

pericardit is, advanced pulmonary emphysema, and thrombosis or

extrinsic obstruct ion of the superior vena cava (as in mediast ina l

tumors). High b lood pressure f rom acute g lomerulonephrit is and

mal ignant hypertension wil l cause per iorbi tal and fac ia l edema. Low

serum albumin wi ll l ead to per iorbi tal and facial edema in nephros is

and c irrhosis. Mucoprotein in the subcutaneous t issue wil l cause

periorbital edema in hypothyroidism.

Other causes for periorbi tal edema are not associated as f requent ly

with edema in the extremit ies. A l lergic or inf lammatory di latat ion

of the capi l laries around the eye lids w il l cause periorbi tal edema indermatomyosit is and trichinosis. A thrombosed cavernous s inus wi l l

al so cause periorbi ta l edema, but this i s s imi lar to

thrombophlebit is of an extremity. Local causes for per iorbital

edema include orbital cel lul i t is, urt icaria, angioneurotic edema,

contusions, and other orbi tal t rauma. The workup for periorbi tal

edema i s s imi lar t o t hat f or edema of t he ext remi ti es (see page

147).



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> Table of Contents > P > PhotophobiaPhotophobia

Sens it ivi ty t o l ight may be due t o l ocal eye di sease or sys temic

di sease, but i n both cases i t i s usual ly due t o i nfl ammat ion, wi th

three except ions: albinism because there i s poor pigmentation of

the i ri s and choro id, al lowing more l ight to get i n; migraine, where

the explanat ion i s s t il l not ava ilab le; and eye s t rain from

astigmatism and, in part icular, hyperopia.

Local eye diseaseFollowing the path o f l ight from the conjunct iva to the ret ina, one

may easi ly recal l the causes o f photophobia. Conjunctivi t is

(chemical , a llergic, and infect ious), kerat i tis, foreign bodies o f the

cornea, i ri t is, ret ini t is, chorioret ini t is, and opt ic neuri t is may a ll be

associated with photophobia.

Systemic disease

Al l the febr i le s tates, especial ly those associated with conjunctival

infect ion, cause photophobia. Measles, meningit is, encephal it is,

hay fever, i nfluenza, the common cold, and t ri chinosis a re just a

few. Certain tox ins can cause photophobia, notably iod ine, bromide,

and atropine derivat ives. Simply stay ing in the dark wil l cause

photophobia. Hysteria and s imple fear or annoyance with crowds

wi ll a lso cause this condi t ion.

Approach to the DiagnosisThe approach t o t he di agnos is o f photophobia i s t he same as t hat

of blurred vi s ion (see page 67).



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> Table o f Contents > P > Po lycythemiaPolycythemia

Pathophys iology wi ll help to form a l i st of diagnost ic poss ibi l it ies

in a case of polycythemia. Fi rs t, i t i s important t o exclude those

cases o f polycythemia that are due to a reduced plasma vo lume

such as dehydration, d iarrhea,

P.355

and Ga isbck syndrome in which the actual red cel l mass i s

normal. Next, separate those cases o f polycythemia that are caused

by an outs ide s t imulus to the bone marrow. Th is i nvolves two

groups: Those wi th anoxia a s t he s timulus and those wi th t he

hormone erythropoietin as the st imulus. The anoxic group includes

pulmonary emphysema, alveolar hypoventi lation, and cyanotic

congenital heart d isease. The group with erythropoiet in as the

stimulus includes pheochromocytoma, Cushing disease,

hydronephrosis, renal cel l carcinoma, renal cyst, cerebel larhemangioblastoma, and hematoma. F inal ly, we are le ft with the

form of po lycythemia that has no

P.356

outside st imulus for red cel l production: polycythemia vera. This i s

most l ikely a neoplas ti c di sorder, and, i n fac t, i t has been t ermed a

myeloprol iferat ive syndrome. In this d isorder, there i s a lsoleukocytosis and thrombocytosis, which are d ist inguishing features.



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Periorbital and facial edema



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Pol c themia


Blood volume studies, serum and urine osmolal i ty s tudies, and

electrolyte assessment wi ll he lp d i fferent iate relative or spurious

forms of polycythemia. Arter ia l b lood P.357

gas analys is w il l d is tinguish those cases associated wi th anoxia

such as pulmonary emphysema and cyanot ic heart d isease.

Determining the b lood erythropoietin wil l help to d if ferent iate

cases o f erythropoiet in as the st imulus.

Other Useful TestsCBC (polycythemia)

Platelet count (polycythemia vera)

Chemistry panel ( renal d isease, heart d isease)

IVP (hypernephroma)

CT scan of the abdomen (hypernephroma)

Chest x-ray (pulmonary emphysema)

Pulmonary funct ion studies (pulmonary f ibrosis oremphysema)

Cardiac catheterizat ion (congenital heart d isease)

Pulmonary consult

Hematology consult

Bone marrow examination (myeloproliferative disorder)



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> Table of Contents > P > PolydipsiaPolydipsia

Excess ive thi rst i s best analyzed by the app li cat ion o f physiology.

Increased des ire for water may be due t o a decreased intake, as

in prolonged abst inence, vomit ing of py loric s tenosis and intestinal

obstruct ion, and d iarrhea of any cause. Poor transport of f luid in

hemorrhagic or vasomotor shock and CHF may be the cause.

Anything that decreases the e ffect ive c i rculatory volume, such as

hypoalbuminemia, may cause retent ion of sal t and consequent

thirst through the reninangiotensinaldosterone mechanism.

Increased output of water may be respons ible for polydips ia. The

increased output may resul t from a solute d iures is i n d iabetes

mel l i tus and hypercalcemic states (e.g., hyperparathyroidism); an

increased g lomerular f i l trat ion rate in hyperthyroidism; inabil i ty of

the k idney to respond to ant idiuretic hormone (ADH) in chronic

glomerulonephrit is, a ldosteronism, and renal d iabetes insipidus; or

a l ack of ADH i n diabetes i ns ipidus . Increased output of salt andwater i n excessive sweat ing of work or fever wi ll l ead t o t hi rs t. Thi s

mechanism is an addit ional factor in hyperthyroidism and diabetes

mel l itus where d iaphoresis i s common.

A neurosis may be responsible for polydipsia in neurogenic diabetes

insipidus. Drugs such as l i thium and demeclocycl ine hydrochloride

(Declomycin) can damage the d ista l tubule and cause renal

diabetes ins ipidus. Drugs such as bel ladonna alkaloids,amitriptyl ine hydrochloride, parasympatholytic drugs, and gal l ic acid

may cause a dry mouth and an excess ive thi rst . A lcohol may cause

excessive thi rst by inhibi t ing ADH.


The approach to the d iagnosis o f polydipsia involves establishing

the presence or absence o f o ther symptoms such a po lyuria,

polyphagia, weakness, and weight loss. Polydipsia wi th polyuriaand excessive appet i te (polyphagia) should suggest d iabetes



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mell i tus or hyperthyroidism, whereas polydipsia with polyuria a lone

should suggest a form of diabetes ins ipidus (pi tui tary, renal , o r

psychogenic). The laboratory workup involves checking intake and

output, b lood sugars, e lectrolytes, and a thyroid profi le.

Other Useful TestsUrinalysis (renal or p i tuitary d iabetes insipidus)

Serum and urine osmolal i ty (d iabetes insipidus)

Serum parathyroid (PTH) level (hyperparathyroidism)

Serum ADH level (diabetes ins ipidus)

24-hour urine calcium (hyperparathyroidism)

Serum growth hormone, luteiniz ing hormone (LH), and

foll icle-stimulating hormone (FSH) levels (pituitarytumor)

HickeyHare test (diabetes insipidus)

Pi tressin test ( renal d iabetes ins ipidus)

CT scan or MRI of the brain (pi tui tary tumor)

Microscopic examination of the urinary sediment (chronic

renal d isease)

Case Presentation #73A 44-year-old white male YMCA Summer Camp supervisor

complained of a 1-week h istory o f excessive thi rst , polyuria, and

weight l oss. He denied fever, chi ll s, o r palpi tat ions.

Question #1. Utilizing your knowledge of physiology, what would

be on your list of possible causes?

Further history reveals that he has a ravenous appetite. Physical

examination was unremarkable, but he had a sweet odor to hisbreath. Urinalysis revealed 4+ glucose and was strongly positive

for acetone.

View Answer

Hyperthyroidism

Diabetes mel l i tus

Hyperparathyroidism

Diabetes insipidusChronic renal d isease

Psychogenic polydipsia



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View Answer

Diabetic acidosis

Final Diagnosis: Diabet ic acidosis



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> Table of Contents > P > PolyphagiaPolyphagia

The causes of i ncreased appeti te are s imi lar t o t hose of obes ity

and can be recall ed wi th t he help of physiology.

P.358

The appet ite may be based on a psychi c des ire for food, a l ack of

food or a part icular vi tamin, impai red intake o f f ood, an increased

metaboli sm o f the body (and consequent ly an increased need for

food) , i ncreased uptake of food by t he cel l, and i nabi li ty of t he cel l

to absorb food, causing cel l s tarvat ion.



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Pol di siaPsychic desire for food. Th is occurs in many chronic



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anxiety and depressed s tates and i s f requent ly

associated with obesity.

Lack of food or a particular ingredient in food.

Starvation and avitaminosis can cause polyphagia.

P.359



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Pol ha iaImpaired uptake of food. Rapi d mobi li ty of food i n

gastric hypersecretion and intestina l bypass as wel l as

preempt ing o f food by intest inal worms may cause

polyphagia on this basis.

Increased body metabolism. Hyperthyroidism, rapid

growth of adolescence, and gigantism are included in

this category.

Increased uptake of food by the cell. Any condi t ion

associated with hyperinsulinism (functional

hypoglycemia and insulinomas) is recall ed in t hi s

category.

Cell starvation. Here diabetes mel l itus andacromegaly are associated with d iabetes where the cel l

cannot absorb glucose.

P.360


Associat ion wi th o ther symptoms i s the key to a def ini t ive

diagnosis o f polyphagia. Thus, polyphagia and obesi ty suggest an

is let cel l adenoma. Polyphagia wi th polyuria, polydipsia, weakness,

and weight loss suggest hyperthyroidism or diabetes mel l i tus.

The laboratory workup should include thyroid funct ion studies, a

skul l x-ray for pi tui tary s ize, g lucose tolerance tests, and, possibly,

a 48-hour fast w ith frequent b lood sugar determinations. An MRI of

the pi tui tary i s the best way to reveal microadenomas.


A 28-year-old white man complained of a ravenous appeti te for

several months.

Question #1. Utilizing your knowledge of physiology, what would

be your differential diagnosis?

Further history reveals that the patient had experienced

episodes of weakness, palpitations, and sweating during the

same period of time. He had recently gained 25 pounds.



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View Answer

Hyperthyroidism

Cushing syndrome

Islet cel l adenoma

Diabetic mell itusPituitary adenoma

Tapeworm infestation



View Answer

Insulinoma

Final Diagnosis: Insul inoma was confi rmed by s ignif icant

hypoglycemia during a 72-hour fast and exploratory surgery.



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> Table of Contents > P > PolyuriaPolyuria

Polyuria i s an absolute increase in the urine output i n a 24-hour

period. The average individual excretes 1,500 mL o f ur ine a day.

Many physiologic condit ions increase the output o f urine (stress,

exercise, and warm weather associated with copious dr inking). From

a pathophysiolog ic s tandpoint, polyuria resul ts f rom one of four

mechanisms: (a) increased intake of f luids, (b) increased

glomerular f il t rat ion rate, (c) increased output o f solutes such as

sodium ch loride and glucose, and (d) i nabi li ty o f the kidney to

reabsorb water i n the di s ta l tubule.

Increased intake of fluid. As a lready ment ioned,

increased intake can occur under stress and nervous

tension. I t becomes pathologic in psychogenic diabetes

ins ipi dus when 6 t o 10 L of flui d may be i nges ted each

day.

Increased glomerular filtration rate. This is a fact or inthe polyuria o f hyperthyroidism and fever o f any cause.

Increased output of solutes. Uncontrol led d iabetes

mel li tus (where the solute i s glucose) and

hyperthyroidism (where the solute may be g lucose or

urea) are examples o f thi s type o f polyuria .

Hyperparathyroidism is another important cause

(increased calcium output). Diuret ics are a s ignif icantcause o f thi s type of po lyuria because they increase the

amount of solute arri ving at t he di stal t ubule and hold

onto the water that would o therwise be absorbed.

Decreased reabsorption of water in the distal tubule.

This , the most common cause o f polyuria, i s divided into

two groups: Condi t ions in which there i s i nadequate or

blocked output o f ADH and cond it ions in which the d is ta l

tubule and col lect ing ducts a re unable to respond to the

ADH. Decreased output of ADH occurs in d iabetes



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insipidus f rom pituitary tumors, infarcts,

HandSchllerChristi an disease, and sarcoidosis

among o ther causes. I t al so resul ts from alcohol

intoxicat ion and hypothalamus les ions. The inabi l i ty o f

the di stal t ubule t o respond t o ADH occurs i naldosteronism, chronic glomerulonephritis, polycystic

kidneys, pyelonephritis, l i thium and demeclocycline

(Declomycin) therapy, and idiopathic nephrogenic

diabetes ins ipidus. D iuretics operate somewhat in this

manner.

Cases o f myxedema with po lyuria have been reported, but the

mechanism is unclear.


The diagnos is o f polyuria depends l argely on the associat ion of

other symptoms. Polyuria, polyphagia, and polydipsia suggest

diabetes mel l i tus and hyperthyroidism. Polyuria with only polydipsia

suggests psychogenic or idiopathic diabetes ins ipidus; the

HickeyHare test wi ll d if ferent iate the two. Polyuria with

po lydips ia and weakness but w ith no s ign if icant weight l osssuggests hypercalcemia and possible hyperparathyroidism. Chronic

nephri t is w il l be d iagnosed by examination o f the urine sed iment

and a speci f ic gravi ty that remains a t 1.010. Nephrogenic diabetes

insipidus can be d if ferent iated f rom neurogenic diabetes ins ipidus

by the i nabi li ty of t he kidney t o respond t o a pi tressin i njec tion.

Other Useful Tests

Thyroid profile (hyperthyroidism)Glucose to lerance test (diabetes mel l i tus)

24-hour intake and output (diabetes ins ipidus)

Addis count (chronic nephrit is)

Serum ADH assay (diabetes ins ipidus)

Serum and urine osmolal i ty (p ituitary d iabetes insipidus,

nephrogenic diabetes insipidus)

Spot urine sodium (diabetes ins ipidus)P.361



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Pol uriaP.362

CT scan o f the brain (d iabetes ins ipidus)

PTH assay (hyperparathyroidism)

Endocrine consult


A 38-year-old whi te woman p resents to your o ffi ce wi th a hi s tory o f

weakness, fat igue, depression, and frequency of urinat ion over the

past year. She denies fever, dysuria, or s ignif icant weight loss.

Question #1. Utilizing your knowledge of pathophysiology, whatis your differential diagnosis?

Further history reveals that she had an episode of right flank

pain and hematuria 6 months ago.

View Answer

Hyperthyroidism

Diabetes mel l i tus

Chronic glomerulonephritis

Pyelonephritis

Diabetes insipidus

Primary hyperparathyroidism

Aldosteronism

Endogenous depression


View Answer

Primary hyperparathyroidismFinal Diagnosis: Primary hyperparathyroidism was confirmed by

repeatedly e levated serum calcium and parathyroid hormone

assays.



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> Table o f Contents > P > Popli teal Swel lingPopliteal

Swelling

The key t o recal li ng the causes of a popl itea l swel li ng i s anatomy.

Each s tructure i n t he popl itea l space may be i nvolved by one or two

condi t ions that cause a mass or swel ling. In vi sua li zing the

anatomy, one encounters the skin, subcutaneous t issues, muscles,

bursae, veins, arteries, lymphatics, nerves, and bones.

Skin. The skin may be involved by urt i caria, sebaceous

cysts, carbuncles, l ipomas, hemangiomas, and various

other skin masses.

Subcutaneous tissue. L ipomas, sarcomas, and cel lul i tis

are the main lesions encountered.

Muscle. Contus ions o f the gast rocnemius and

semimembranous muscles may cause a mass in the

popl iteal fossa.Bursae. Popl itea l cysts (Baker cysts) may resul t from

f il l ing o f the bursa between the gast rocnemius and

semimembranous muscles wi th a gelatinous or serous

substance.

Veins. T he veins may enlarge from a vari cocele or

thrombophlebitis.

Artery. An aneurysm o f the pop li tea l artery may resul tf rom atheroscleros is o r a gunshot wound. When there i s

a l oud brui t over t he artery and di stention o f t he veins ,

an arteriovenous f istula should be considered.

Lymphatics. En larged popl i teal nodes may resul t f rom

infections in the d is tal port ion o f the ext remity,

tuberculous adenopathy, or metastatic malignancy.

Nerves. Traumatic neuromas or neurofibromas may

involve the nerves here.

Bone. Exostos is ari s ing from the epiphysea l cart i lage o f



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> Table of Contents > P > PriapismPriapism

This unfortunate condit ion may be humorous to everyone but the

one who i s blessed wi th i t. The common causes are few,

and the mnemonic MINT i s an easy method for recall of t hese.

MMalformation suggests ph imosis and o ther

deformit ies o f the penis.

IInflammation and intoxication suggest posterior

urethri t is , prostat i ti s , and cyst it i s, as wel l a s

aphrodis iac drugs such as s i ldenafi l ci t rate, a lcohol ,

cannabis, indica, camphor, and damiana.

NNeoplasms s uggest two common causes of

priapismchronic lymphatic or myeloid leukemia

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and nasa l polyps. The N al so suggests neurologic d isorderssuch as neurosyphi l is, multiple sclerosis, and d iabet ic

neuropathy.



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Po liteal swellinTTrauma recal ls not on ly di rect t rauma to t he pen is

producing a l oca l hematoma but a lso t rauma to the

spina l cord with f ractures or contusion.


The diagnos is o f pr iapism usua lly depends on the associat ion o f

other symptoms and s igns (e.g. , boggy p rostate) , but a blood



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smear or bone marrow examination may be necessary to exclude

leukemia. A carefu l hi s tory of the patient's sexual act ivi t ies to rule

out too-frequent masturbat ion or sexual excesses may be indicated.

Other Useful Tests

CBC (leukemia, s ickle cel l anemia)

Coagulat ion studies (blood dyscrasias)

Prostat ic massage and examinat ion of the d ischarge

(prostatitis)

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Pria ismUrine culture (cystit is, pyelonephritis)



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> Table o f Contents > P > Prostat ic Mass or En largementProstatic

Mass or Enlargement

Prostatic mass or enlargement

General ly, when the phys ician examines the prostate in a routine



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be done i f t he pat ient has fever and s igni fi cant t enderness of t he

prostate. I t i s bet ter to proceed w ith ant ibiot i c therapy and

reexamine the pat ient a fter the fever has subs ided. A smear and

cul ture o f the d ischarge i s made. If upon examining the di scharge

under h igh-power microscopy, four or more white b lood cel ls (WBCs)per h igh-power fi eld are found, the d iagnos is o f p rostat i t is can be

made. If benign prostat ic hypertrophy i s suspected, cystoscopy and

retrograde pyelography can be done.

Other Useful Tests

CBC

Sedimentation rate ( infection)

Chemistry panel (uremia)Urinalysis (cyst it is, UTI)

Cystogram (prostatic hypertrophy)

Skeletal survey (metastatic carcinoma)

Bone scan (metastat ic carcinoma)

Acid phosphatase level (metastat ic carcinoma)

CT scan o f pelvic l ymph nodes (metastas is)

Lymphoscintigraphy (node metastasis)Cystoscopy (bladder neck obstruction)



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> Table o f Contents > P > ProteinuriaProteinuria

There are many causes of proteinuria. The mnemonic VINDICATE is

a he lpful way of deve loping a l is t of poss ibi li ti es .

VVascular c ategory should cal l t o mind CHF,

hypertension, and renal vein thrombosis.

IInflammation. An important cause o f p rote inuria i s

UTI. In add it ion to the common bacterial i nfect ion, one

should not forget tuberculosis, schistosomiasis, v iral

hepatit is, syphi l is, and malaria.

NNeoplasm category includes Wi lms tumor, renal

cel l carcinoma, papi lloma of the rena l pelvis and

bladder, and mult iple myeloma.

DDegenerative di sorders are not a common cause o f

proteinuria.

IIntoxication category includes tox ic react ions to

gold, mercury, gentamycin, penici l lamine, captopri l, andant iconvulsants. There are many other drugs that cause

proteinuria. Idiopathic prompts the recal l of o rthostat i c

proteinuria.

CCongenital causes should bring to mind polycyst ic

kidneys, Alport syndrome, Fabry disease, horseshoe

kidney, and other congenital anomalies.

AAllergic and autoimmune s hould cal l t o mind acuteglomerulonephritis, col lagen diseases, Wegener

granulomatosis, HenochSchnlein purpura,

amyloidosis, sarcoidosis, and chronic interst it ia l

nephritis.

TTrauma. The kidneys a re involved in various forms

of t rauma causing proteinuria, but usually there i s

associated hematuria. Stones should a lso be included in

this category because they cause t rauma, inducing

proteinuria and hematuria.



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ProteinuriaCT scan o f the abdomen and pelvis (neoplasm,

malformation)

Retrograde pyelography (neoplasm, hydronephrosis)

Nephrology consult

Renal biopsy (glomerulonephritis)

Renal angiogram (renal artery stenosis, renal vein

thrombosis)



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> Table of Contents > P > PruritusPruritus



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> Table of Con tents > P > PtosisPtosis

A droop ing eye lid may resul t from di rect i nvolvement o f the l evator

palpebrae superioris muscle (end organ) or f rom involvement o f the

sympathet ic or oculomotor nerve pathways from the muscle to the

central nervous system. Consequently, visual iz ing neuroanatomy

is t he key t o a di fferent ial di agnos i s.

End organ ( levator palpebrae superioris muscle). The

end organ can be involved in congenital p tosis

(defect ive development o f the muscle), injury to the

tendon of the muscle, neoplasms of t he eye or orbi t, or

dermatomyositis.

Sympathetic pathway. I f the sympathetic pa thways are

involved there i s a lmost invariably an associated miosis

and enophthalmos (Horner syndrome). The les ion may be

a long the intracranial pathways of the postgangl ionic

f ibers around the carot id artery in internal carot idaneurysms, thrombosis, and migraine. Orbital cel lul i t is

or tumors may rarely a ffect the sympathetic nerve

pathways here. The l es ion may be i n t he s te ll ate

gangl ion and i ts connect ions in cervical rib, scalenus

anticus syndrome, Pancoast tumors, cervical Hodgkin

lymphoma, and brachial p lexus injuries. The les ion may

be i n t he spinal cord or nerve roots i n spinal cordtumors, syringomyelia, syphil is, thoracic spondylosis,

metastat ic carcinoma, myeloma, or tuberculosis o f the

spinal column. Final ly, t he l es ion may be i n t he

brainstem in g liomas, poster ior inferior cerebel lar artery

occlusions, syringobulbia, and encephalit is.

Oculomotor nerve pathways. W hen the ptosis is due to

involvement in this pathway, there are usual ly other

extraocular muscle pals ies as wel l . The levator muscle

may be af fected by myotonic dystrophy. The myoneural



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PtosisI f oculomotor involvement i s certa in, a g lucose tolerance test, skul l

x-rays, sero log ic tests for syphi l is , spina l tap ( if no

contraindicat ions), CT scans, and, possibly, arter iography are

indicated. The need for other tests depends on the presence o f

other neurologic s igns. An ophthalmologist and neurologist should

probably be consul ted in a ll cases o f uni la tera l ptos is.

Other Useful Tests

CBC (orbital cel lul i t is)ANA analysis (col lagen d isease)

Acetylcholine receptor ant ibody t i ter (myasthenia gravis)



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MRI of the brain (brain tumor or other space-occupying

lesion)

Cerebral angiogram (cerebral aneurysm)

Response to intravenous thiamine (Wernicke

encephalopathy)24-hour urine creatinine and creatine (muscular

dystrophy)

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> Table of Contents > P > Pulsat i le MassPulsatile Mass

Simply by t hinking of t he l ocat ion o f the pul sat il e mass, one can

ident ify t he cause or causes of a pu lsat il e mass.

Orbit. Th is i s most l ikely an ar teriovenous f is tula

related to t rauma or the spontaneous rupture o f an

aneurysm into the cavernous s inus.

Neck. A carotid, innominate, or brachia l artery aneurysm

is t he most l ikely cause here, but pul sat ions may be f el t

in the neck from aort i c regurgi tat ion as wel l.

Chest. An aneurysm of t he thoraci c aorta i s t he most

l ikely cause here, but an enlarged heart or cardiac

aneurysm may give a not iceable heave on inspect ion.

Abdomen. T ricuspid regurgitat ion may cause pulsat ions

o f t he l iver i n t he ri ght upper quadrant , but t he

associated asci tes and dependent edema should make

the diagnos is obvious. A pulsat ing abdominal aorta i susua lly an a therosclerot ic aneurysm, but i t may be an

abnormal f inding in asthenic i ndividuals . I t i s al so

possible t hat t he pul sat ing mass is a t umor over a

normal abdominal aorta.

Extremities. A pul sat ing mass i n t he axi ll a, groin, or

pop li tea l f ossa i s usual ly an aneurysm, but

osteosarcoma can produce a pulsating mass a long wi theggshell cracking.


Ultrasonography wi ll usually confi rm the d iagnosis o f these lesions,

but a CT scan or angiography may be necessary, part icularly when

surgical intervent ion i s p lanned. A card iovascular surgeon should be

consulted before ordering these expensive tests.



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> Table of Contents > P > PyuriaPyuria

Pyuria i s i ncluded here al though i t i s not a symptom or a defini ti ve

f inding on physical examinat ion. Examinat ion of the urine, however,

i s so frequently a par t of every phys ical examination that the

causes of pyuria should be ava ilable for immediate recal l fo r al l

primary care physicians.

As in other cases of puru lent d ischarge, i nflammat ion i s the cause

of pyuria i n most cases, thus an e tiolog ic mnemonic would seem

unnecessary. However, the mnemonic MINT must be cons idered at

the outset so that one reca ll s the mal format ions, neoplasms, and

traumat ic foreign bodies that may cause an obst ruct ion or provide a

frui t ful so i l for bacteria l growth. Unl ike a nonbloody d ischarge

elsewhere, pyur ia i s rarely associated wi th inflammation of a

noninfectious nature; more than that, i t i s almost i nvariably due to

bacteria. What i s more, the bacteria are usually Gram-negat ive

bacill i, particularly Escherichia coli, Enterobacter, Proteus, orPseudomonas organisms.

W ith t hi s i n mind, l et us vi sual iz e t he anatomy of the

genitourinary t ree and develop a system for ready recal l o f the

diagnostic possibi l i t ies. The urethra bri ngs t o mind al l t he various

causes o f u rethri t is (see page 442). The prostate reminds one of

prostat i t is and prostat ic abscess. The bladder suggests cyst it is ,

stricture, Hunner u lcers, calcul i , and papil lomas that may ini t iateinfect ion. Some urologists may recal l f inding a vesicovaginal f i stula

or rectovesical f i stula in patients who have had previous abdominal

surgery; a fi s tula may al so form in regional i le it i s. The ureters

suggest the numerous congenital anomalies (e.g., stricture,

congenital band, and aberrant vessel) that may cause obstruct ion

and infect ion. The renal pelvis and kidney reca ll pyel it i s and

pyelonephr it is, as wel l as renal carcinoma, calcul i , and congenital

anomal ies, a ll o f which may contribute to i nfection.

The rare causes of pyuria must be cons idered. Tuberculos is of the



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kidney should be ment ioned, because when routine cul tures are

negat ive, t hi s i s one o f t he condi ti ons t o l ook for. Even

act inomycosis can cause pyuria, thus a cul ture on Sabouraud media

may be warranted. Although Bilharzia haematobium parasi tes

usual ly cause hematuria, pyuria i s occasional ly the ini t ial f inding.An interst i t ia l nephri t is o f tox ic or autoimmune origin may

occas ional ly cause a shower of eos inophi ls i nto t he urine .

Final ly, t here is probably not a surgeon al ive who has not been

foo led by the pyuria o f an acute appendici t is , salpingi t is , o r

diverticulitis.


How does one t rack down the cause of pyuria? F irs t, it must bedetermined that the c loudy urine i s real ly pyuria. Amorphous

phosphates and other i nert material w il l di sappear on t reating the

urine wi th di lute aceti c acid. Then, just as for o ther nonbloody

discharges, one must do a smear and cul ture for the o ffending

organism; an examination of the urine, especia lly the unspun

specimen, i s axiomatic. I f one finds clumps o f l eukocytes, renal

gi t ter cel ls , or WBC casts, the infection a lmost certainly comesfrom the k idney. Mot i le bacteria in an unspun specimen examined

under h igh-power microscopy and a colony count of over 100,000

per mL s ign ify i nfection. A three-glass test may be helpful i n

loca li zing the s i te o f o rigin o f the pyuria. Anaerobic cul tures and

cultures for Chlamydia may be needed. Look for eos inophi ls on a

Wright s tain o f the urine i f t oxic nephri t is i s suspected.

Vaginal examination and cu lture may di sclose a source for the

infection. In the male, one episode o f pyuria should be suf fi cient

indi cat ion for an IVP; a female should have one af ter her second

episode, especial ly i f no cause can be found on phys ical

examinat ion. Cystoscopy and a voiding cystogram are o ften

indicated a t thi s t ime.

Other Useful Tests

CBC (pyelonephritis)Sedimentation rate (pyelonephritis)

Chemistry panel (diabetes mel l i tus, nephrit is)



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ANA analysis (col lagen d isease)

Retrograde pyelography (tumor, malformation,

obstructive uropathy)

Urine for acid-fast bacil lus (AFB) smear and cul ture and

guinea p ig inoculat ion (tuberculosis)Sonogram (divert iculum, pelvic mass, cyst, abscess)

CT scan of abdomen and pelvis ( tumor, mal format ion,

obstructive uropathy, extrinsic mass)

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DifferentialDiagnosisInPrimaryCare 4thEdition

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