Does my patient have Lupus?

Jammie Barnes, MDAssistant professor

Department of Medicine, Division of Rheumatology

http://www.youtube.com/watch?v=bueW1i9kQ

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It’s Lupus

LBJ referral: +ANA with aches and pains Dr. Barnes: It’s Lupus Dr. Warner: Wrong Another referral: same story Dr. Barnes: It’s Lupus Dr. Warner: Wrong A retrospective chart review at LBJ (1yr)

104 +ANA referrals…. ONLY 6 cases of confirmed SLE

Dr. House or Dr. Warner

Understand the limitations of sensitivity and

specificity of ANA Determine who needs to be evaluated for SLE Describe the systemic signs and symptoms of

SLE Apply the American College of Rheumatology

criteria for SLE Apply to cases

Objectives

ANA is 100% sensitive

Diabetes

Lupus

Sensitivity & Specificity

SnNout: high sensitivity – negative test is good at ruling out the disease

Negative ANA – very unlikely to have SLE

SpPin: high specificity –positive test good at ruling in disease

Sensitivity – 100% Specificity – 60%

Prevalence = 10/1000 = 1%

Yes- SLE

No- SLE

+ test 10 390 400

- test 0 600 600

10 990 1000

Prevalence = 500/1000 = 50%

Yes – Dz

No - Dz

+ test 500 200 700

- test 0 300 300

500 500 1000

PPV: 10/400 = 2.5%

PPV: 500/700 = 71.4%

The nomogram

LR: 2.5

Reminder: +LR= sens/(1-spec)

Consider prevalence Clinical scenario in your patient If you order a test – expect a result

Pretest probability

Positive ANA, now what!!

Autoabs directed against DNA

or snRNP Positive test: >1:80 Best to order test by

immunofluorescence (IF) ELISA enzyme linked assays

are cheaper but have 80-98% agreement with IF

ACR recommends ordering ANA by IF

ANA

1/3 of healthy people have an ANA 1:40 5% of healthy people have ANA 1:160 3.3% of healthy people have ANA 1:320 Healthy 1st degree relatives can have +

ANA Healthy older people increased + ANA ANA linked to thyroid dz, hepatitis,

environmental exposure, cancer, infections and drugs

Other problems with ANA

Southern Medical Journal. Vol 105, no 2, Feb 2012

2 possibilities Raise the threshold of positive test

High titers do warrant more investigation > 1:1280

Couple the test with more specific signs and symptoms of rheumatic disease

High risk - low occurrence

Making the ANA better

When to order an ANA

Criteria – seizures and psychosis

Both in absence of offending drugs Question: Have you ever had a seizure or convulsion?

CNS/PNS

Orphanet Journal of Rare Disease 2006 1:6

4 criterion for skin: malar rash, discoid rash,

photosensitivity and oral ulcers Do you get sores in your mouth or nose for more than 2

weeks at a time Rash on your cheek for more than a month Skin breakout (rash) after being in the sun (not a sunburn)

Others: Alopecia

Have you had rapid loss of hair Raynauds

Have your fingers ever shown unusual color changes in the cold

Purpura, urticaria and vasculitis

Skin/Mucocutaneous

Hemolytic anemia Leukopenia <4000 on > 2times or

lymphopenia <1500 on > 2 times Thrombocytopenia <100k in absence of drugs All meet hematologic criteria (only get 1 point) Questions: Have you ever been told that you

have anemia, low blood count, low platelet count

Hematologic

Criteria:

Pericarditis – documented by ECG, rub or pericardial effusion

Pleuritis – convincing h/o pleuritic chest pain, rub or pleural effusion

Question: Do you get chest pain with deep breath? 1 point

Others: Endo and myocarditis, pulmonary arterial

hypertension, valvular, CAD Chronic interstitial pneumonitis, acute lupus

pneumonitis, acute alveolar hemorrhage, acute reversible hypoxemia, PE, shrinking lung syndrome

Cardio/Pulm

Criteria: Persistent proteinuria >0.5gm per day or 3+

on dipstick or cellular cast Have you have been told you have protein in

your urine Class 1-6 of lupus nephritis Microangiopathic glomerular disease Renal vein thrombosis

Renal

No criteria for diagnosis None specific abd pain, nausea and vomitting Rare mesenteric vasculitis

GI

Not a criteria LAD HSM

Reticuloendothelial

Criteria: Arthritis – tenderness, swelling or effusion in 2

or more joints witnessed Typically non-erosive Jacouds arthopathy Others:

Myositis

MSK

Not a criteria Profound fatigue (disabling fatigue) – in

absence of depression Fever (no signs of infection) Weight loss

Constitutional

Criteria: Positive ANA >1:80 Positive anti-dsDNA OR Anti-Smith OR

antiphospholipid antibody Abnl IgG or IgM cardiolipin, + lupus

anticoagulant, false positive RPR Others:

SSA/B (anti-Ro and La), RNP

Immunologic

Upon screening: Two or more organs systems involved – order

CBC, CMP, UA to evaluate for systemic disease If above reveals possible systemic disease

then order an ANA and possible other antibodies

If 4 or more criteria by ACR or suspect SLE refer to Rheumatology

Applying Signs and Sxs

21 y/o college student with two months of

joint pain worse in AM Notices faint rash on face for last month Very tired and finds it difficult to concentrate

in class Denies fevers, abd pain, chest pain, diarrhea

or constipation On exam: malar rash, decreased breath

sounds at bases, no murmurs, diffuse cervical LAD and mild synovitis in the MCPs and PIPs

Case

Order labs/studies: CBC, UA, CMP, CXR What other labs do you want? ANA, RF, CCP and TSH WBC count 3.2, nl Hgb and platelets, neg RF

and CCP, UA 2+ proteinuria, no cast or red cells, UPC 0.3, ANA 1:640, +dsDNA, +smith and chest xray with effusions

Does she meet criteria? YES!

What next

36 y/o stay at home Mom presents with joint

pains for 3 months She has no swelling, but she has tenderness

all over in the upper and lower body She tells you she has anemia, severe fatigue

but she can still take care of her children She has occasional HA, some weight gain, but

other ROS is negative On exam she is overweight with BMI of 32,

multiple tender points but no synovitis

Case

Order CMP,CBC, UA and TSH Her labs are normal with exception of HGB of

10.2 and MCV of 76 What next: Iron studies Low ferritin, smear: hypochromic RBCs, low

iron and high TIBC Do you need to do more? Treat IDA

What next

32 y/o man with long standing history of

epilepsy. He has been on anti-seizure medication for many years. Initially he was on phenytoin and now on oxcarbazepine

He has developed a photosensitive rash and joint pain

In ROS he also has pleuritic chest pain On exam he has a erythematous rash on the

face and upper chest, synovitis of the bilateral wrist but rest of exam is normal

Case

CBC, CMP, UA, CXR and ANA He has positive ANA, nl CMP, CMP, UA and chest xray What does he have? Drug induced lupus Do you need histone antibodies? No How do you proceed? Discuss changing anti-convulsant medication, may

add NSAIDs, steroid cream for rash and hydroxychloroquine

What next

Remember ANA does not equal lupus Need careful history and physical Lupus is RARE disease but high morbidity and

mortality if missed

Please remember your packet!! I need to contact you again in 3months for

post test!!!

Thank you for time