Paeds RashesKawasaki disease

Epidemiology: infants and children effected; 85% <5yrs, 30% <1yr; peak occurrence 18-24/12; most common cause of acquired paediatric heart disease; incr in Asian / Blacks; 9-20:100,000Pathophysiology: Generalised systemic vasculitis of medium sized vessels (inc. coronary, renal, hepatic, splanchnic) of unknown cause (likely post-infectious, due to super Ag bacterial toxins)

Phases:Acute febrile phase: weeks 0 - 2; myocarditis (25%; resolves alone), pericarditis (resolves alone), pericardial effusion (rarely large), valvular dysfunction, LV dysfunction (50%), arrhythmias; MI (1%); conduction defects (20%); coronary arteritis beginsSubacute phase: weeks 2 -3Convalescent phase: weeks 4 - 6

Symptoms: fever for 1-2/52; tachycardia out of proportion to fever, gallop rhythmIx: ECG: non-specific ST-T waves changes (in 7%) CXR bloods (anaemia for age, decr alb, incr plt, incr WBC, incr ALT, incr ESR and CRP ++, decr alb), ASOT / anti-DNAase B urine (sterile pyuria) echo (perform at initial presentation at 2/52 at 6/52 at 1yr; may not need to do initial echo if present <10/7 with normal ECG)Complications: Coronary artery aneurysms (20% untreated children) occur in 2nd – 4th week (can be as early as 3/7 or be delayed 6-8/52; RF for development: male, <1yr, >5yrs, fever >10/7, decr alb / Hb, clinical signs of cardiac involvement); stenosis, thrombosis; MI is leading cause of death; 75% fatalities occur within 6/52; children <6/12 at incr risk of developing cardiac complications so have lower threshold for diagnosis in this group; mortality <1%; excellent prognosis if trt within 10/7 and normal echo

Diagnostic Criteria1) Fever >5 days (abrupt onset; in 100%)2) 4 out of 5 of following: can have <4 if echo shows CAD; those <6m

old may have incomplete presentation (2-3 criteria); all the below occur within 3/7 of rash

a. Bilat non-exudative bulbar conjunctival injection (with perilimbic sparing) – present in 80%

b. Pharyngeal oedema / red cracked lips / strawberry tongue – present in 90%; lasts 2-3/52; dry, crack and fissure by 6/7

c. Cervical lymphadenopathy – present in 60-98%; usually solitary, unilateral, >1.5cm

d. Diffuse erythema and swelling of hands and feet during acute phase (predilection for perineum, usually accompanies onset of fever; erythema, oedema) periungal desquamation during convalescent phase (after 2-3/52); present in 85-95%

e. Polymorphous generalized rash – present in 99%May also get arthritis (35%), hepatitis (40%), AP, D+V, urethritis is sterile pyuria (70%), asceptic meningitis (25%), pericardial effusion / arrhythmia (20%), gallbladder hydrops (<10%), carditis and CCF (<5%; usually resolves by 6-8/52)

Treatment: Supportive careIVIG 2g/kg over 12hrs symptomatic improvement in 90%, prevents aneurysm in 95% (decr risk of heart abnormality from 20% to 3-5% if given in 1st 10/7); if ongoing fever, may require 2nd dose; aim to commence early than D5High dose aspirin 30-50mg/kg/day until fever gone 3-5mg/kg OD for 6-8/52 helps prevent thrombosis; no evidence that it prevents the formation of aneurysms; must continue on low dose therapy indefinitely if develop aneurysms, otherwise stop at 6/52Corticosteroids if refractory to above treatment

Scarlet Fever

Cause: Group A beta-haemolytic strep erythrogenic toxinIncubation: 2-4/7 (ie. Short)

Sx: Acute onset fever, sore throat, headache, V, AP exanthem develops over 1-2/7 Red tonsils and pharynx covered in exudates Tongue white coating through which red hyptertrophied papillae project (white strawberry tongue) white coating disappears after 4-5/7 red strawberry tongue Bright red / haemorrhagic spots on soft palate. After 12-48hrs Red, finely punctate 1-2mm blanching papules (rough sandpaper) on neck, axillae and groin Rapidly spreads to trunk and extremities. Linear petechial eruptions in antecubital and axillary folds (Pastia’s lines). Fades at 6/7. Desquamates at 2/52, on hands and feet 1st. Facial flushing and circumoral pallor.Complications: OM, sinusitis, rheumatic fever, post-strep GNIx: ASOT, swabTrt: Penicillin 10/7

Measles

Complications: OM (2.5%), pneumonia (4%; responsible for 50% deaths); encephalitis (0.1%; onset 1-2/52 after disease; mortality 10-15%; permanent neuro damage in 40%); subacute sclerosing panencephalitis (can occur 4-10yrs

Cause: RNA myxovirusEpidemiology: rare in immunised; now mostly seen in older patients; highly infectious (90% susceptible close contacts will become infected)Incubation: 7-18/7 (av 10/7); 14/7 between exposure and rash; patient infectious from 5/7 before rash to 4/7 after rash

Case definition: 3-4/7 URTI rash 1. Fever >38 (ie. High)2. Rash: fever always present at time of onset of rash; behind ears

and at hairline spreads from head to feet, inc palms and soles; erythematous maculopapular, red blanching confluence esp on face copper-brownish hue as resolves desquamates after 3/7; lasts 1/52

3. 1 of cough / coryza / conjunctivitis / Koplick spots (white, bluish- white 1mm spots with red base on buccal mucosa; appear 1/7 before rash); may have generalised lymphadenopathy; may be diarrhoea

later, progressive mental deterioration and death); myocarditis, nephritis, hepatitis, pericarditis, keratitisIx: swab for PCR (will be +ive within few days, when serology may still be negative; also useful in immunocomp); blood for serology (IgM = infection, levels peak at 7-10/7; IgG = immunity; may be negative if <4/7 from onset fever, need to do rpt after 1/52, remains +ive for 3/12, sens 100%, spec 98%); double bag specs and don’t send through lamsenTrt: Supportive; need infection control measures; notifiable disease; no school / child care for 5/7; admit if: poor PO intake, resp compromise, CNS complications

Prophylaxis:Exposed if: enter same room within 2hrs of infected person leavingNon-immune if: not had 2x MMR and born after 1969, from 6/12 to 1st vaccine, if >4yrs and not had 2nd vaccine, pregnant, immunocomp, or prem <28/40Offer MMR if <72hrs (not if pregnant); if immunocomp / pregnant / >72hrs, consider Ig

HSP Epidemiology: 2:1000; more Asian / Indian; usually 4-6yrs (2-11yrs); most common in springCause: Allergic vasculitis, follows URTI, IgA mediated; assoc with infection, drugs, vaccines; may be post Grp A strepPathology: Small vessels (skin, GIT, kidneys, jts)

Trt: Usually resolves in 3-4/52; supportive; monitor BP and urine for 6/12; IVF if ill; NSAIDS; Consider prednisone 1mg/kg for 2/52 (if abdo, jt or scrotal disease; may prevent renal complications (2% get long term renal impairment); helps jt pain, abdo pain, oedema)Admit if: Abdo, renal complications; symptomatic relief

Notes from: Dunn, Starship Guidelines

Paeds RashesHow to Describe a Rash

Palpable lesionsPapules <0.5cmNodules >0.5cmVesicles <0.5cm, clear fluidPustules Yellow fluidPurpura Purple; palpable / non-palpable

Non-palpable lesionsMacules Alterations in circumscribed area of skinPigmentation

Assessment

Sx: Palpable purpura on buttocks and legs (extensor surface) – presenting Sx in 50%; maybe also erythematous, urticarial, echymoses, petechaie AP (+N+V+D; in 60-80%; diffuse and colicky; occurs after rash; 50% have blood in stool; 5% get acute GI haemorrhage; 3% get intussusception) Migratory polyarthralgia (66-80%; presenting Sx in 25%; usually resolves after 24-48hrs; in gravity dependent jts) Renal failure (in 20-50%) – nephritic syndrome Generalized oedema (eg. Feet; often painful)Ix: Haematuria and proteinuria in 90%; urine, FBC (plts normal), U+EComplications: Nephritic / nephrotic syndrome, ARF (<1%), HTN; if proteinuria = more severe and needs FU; Intussusception (5%); bowel perf

History Fever, systemic symptoms, prev immunizations, human/animal contacts, travel, bites/stings, drugs, food, environmental exposureInitial location of rash, pattern and timeframe of development, initial Morphology

Examination VitalsUndress – scalp, ears, neck, MM, skinfolds, digits, web interspaces, palms, solesMorphology, location, distribution

ENTEROVIRUSES

Echovirus 9, Coxsackievirus A9Transmission Fecal-oral, oral-oral, RS-oralSx Non-specific febrile illnesses, RTI, GI Sx, meningitis; variety of rashes

Maculopapular rash beginning on face and neck, extending to trunk and feet; may be lesions on buccal mucosa and soft palate (resemble Koplik spots); maybe petechiae, vesicles, urticaria

Duration 5/7

Enterovirus (hand, foot and mouth disease)Sx Fever, anorexia, malaise, sore mouth 1-2/7 later, oral lesions

then cutaneous lesionsOral lesions: painful 4-8mm vesicles on erythematous base on buccal mucosa, tongue, soft palate, gingiva ulcerateCutaneous lesions: 3-7mm red papules grey vesicles on palms and soles (may be dorsum of feet and buttocks) heal in 7-10/7

Trt Hydration, analgesia, mouthwash

Coxsackievirus (herpangina)Sx Fever, mouth pain, oral ulcers

Similar ulcers to hand, foot and mouth; but no skin lesions

RUBELLA

Incubation 12-25/7

Sx 1-5/7 fever, malaise, headache, sore throat irregular pink macules and papules on face, spreading to neck, trunk and arms; coalesces then clearsForchheimer spots: pinpoint petechiae on soft palate that coalesceSuboccipital and posterior auricular lymphadenopathy

Trt Supportive

ERYTHEMA INFECTIOSUM (FIFTH DISEASE, SLAPPED CHEEK)

Sx Abrupt appearance of rash fiery red rash on cheeks; diffuse erythema of closely grouped tiny papules on erythematous base; edges slightly raised; circumoral pallor; sparing of eyelids and chin; lasts 4-5/71-2/7 after face rash nonpruritic macular/maculopapular erythema on trunk and upper limbs spreads; lasts 1/52; spares palms and soles; fades with central clearing

Assoc with fever, malaise, headache, sore throat, cough, coryza, N+V+D, myalgia

Trt Supportive

HERPES

Transmission HSV-2 genital, HSV-1 oralSx Herpes labialis, gingivostomatitis – painful umbilicated vesicles

unroof and crust overEczema herpiticum – break out on area previously affected by eczemaHerpetic whitlow – distal fingers

Trt Consider sexual abuseOral acyclovir; supportive

CHICKENPOX

Sx Pruritic generalized vesicular exanthem with mild systemic symptoms; starts on trunk / scalp as faint red macules vesicular in 24hrs, on erythematous base dry and crust; widespread, palms and soles spared; may occur on MM

Trt Supportive if uncomplicated; cleanse lesions to prevent 2Y infection; antivirals only if immunocompromised

ROSEOLA INFANTUM (SIXTH DISEASE)

Sx Abrupt onset fever lasting 3-5/7, cough, coryza, anorexia, abdo discomfort fever settles appearance of rash over 1-2/7. Erythematous,

blanching, macular/maculopapular eruption, discrete rose / pale pink 2-5mm lesions; most on neck, trunk and buttocks; can also involve face and arms. No MM involvement. Lasts 1-2/7 fades rapidly.

Trt Supportive

IMPETIGO

Cause Staph aureus, beta-haemolytic strepSx Lesions on face, neck, and extremities; usually no systemic Sx

Nonbullous: small erythematous macules and papules thin walled vesicles pustules rupture golden yellow crust smooth red surface underneath; may become confluent; local adenopathyBullous: local; toxin causes separation of skin and bullae; thin walled

bullae 0.5-3cm, filled with clear-yellow fluid, rupture easilyStaph scalded skin syndrome: systemic; malaise, fever, irritability, tender skin; extensive areas of exfoliation; Nikolsky sign +ive

Trt Nonbullous: topical; oral only if severeSSSS: inpatient, IVABx; may require admission to burns unit

ERYSIPELAS

Cause Group A beta-haemolytic strepSx Fever, chills, malaise, vomiting

Local redness, heat, swelling; raised indurated border; well demarcatedTrt Penicillin

SCABIES

Sx Severe pruritis; generalized eruption of linear burrows, papules, pustules, vesicles; mostly affect hand, feet, groin; excoriation from scratching

Trt Permethrin

ERYTHEMA TOXICUM

Sx Erythematous macules 2-3cm on face, trunk, extremities; central 1- 3mm pustules

Trt None

SEBORRHOEIC DERMATITIS

Sx Greasy yellow/red scales, mostly on scalp; not pruriticTrt Mineral oil

NAPPY RASH

Contact dermatitis: erythematous macular/papular with well demarcated borders; trt with hygeineCandidal dermatitis: erythematous papular / pustular lesions; scaling around margins; satellite lesions