Clinical Serology and Lab Testing

Question 1

ESR increases with:

Which sex has greater concentrations?

In what diseases should this be monitored? (2)

Answer 1

Age

FM

PMR (polymyalgia rheumatica) and GCA (giant cell arteritis).

Question 2

What molecules increase CRP?

What can CRP do?

At what lab reading is it considered “inflammatory”?

Answer 2

Proinflammatory cytokines.

Activate complement and promote phagocytosis.

> 8 mg/l.

Question 3

Which rises/falls more quickly: ESR or CRP?

Answer 3

CRP

Question 4

RF is what type of antibody?

What produces it?

Is it more specific or sensitive for RA?

Answer 4

IgM (most common, but can be any) that targets Fc portion of the IgG immunoglobulin.

B cells in synovial joints of RA patients.

Specificity > sensitivity.

Question 5

What suggests a 99.5% specificity for RA?

Answer 5

+ anti-CCP and + RA

Question 6

What diseases are associated with the following ANA patterns?

Homogenous pattern (histone)
Rim pattern (anti-dsDNA)
Speckled: anti-Smith vs. anti-SS-A/SS-B
Anticentromere
Anti-scl 70-PSS

Answer 6

Homogenous pattern (histone): Drug induced lupus.
Rim pattern (anti-dsDNA): SLE.
Speckled: anti-Smith (lupus) vs. anti-SS-A/SS-B (Sjogren syndrome).
Anticentromere: Scleroderma/PSS.
Anti-scl 70: CREST/PSS.

Question 7

What renal lab findings in SLE are required for diagnosis? (3)

What hematologic lab findings are needed? (4)

Answer 7

Renal (need 1 of 3)
-proteinuria > 500 mg/day or > 3+ or casts.

Hematologic (need 1 of 4)

• hemolytic anemia w/ reticulosis.
• leukopenia (< 4000 WBC ct.).
• lymphopenia (< 1500 ct.).
• thrombocytopenia (< 100K ct.).

Question 8

What is the joint fluid analysis (aspiration) in the following:

Normal fluid

Non-inflammatory

Inflammatory

Answer 8

Normal fluid: < 200 cells/mm3

Non-inflammatory: 200-2000 mononuclear cells.

Inflammatory: 2000-50,000 (cloudy, inflammatory and PMNs); > 50,000 (septic).

Question 9

What is the lab finding in gout?

What is the birefringent status of the crystals?

What is the onset like?

What is “tophi”?

Answer 9

Uric acid > 6.8 mg/dl.

Negative birefringent by polarized light.

Acute onset, monoarticular and osten 1st MTP joint.

Nodular deposits of monosodium urate crystals in the skin.

Question 10

What is the treatment for acute gout? (3)

What is used for chronic gout? (2)

Answer 10

NSAIDs
Colchicine - GI toxicity
Steroids

Xanthine oxidase inhibitors.
Probenecid - blocks tubular resorption or urate.

Question 11

Why should Gadolinium IV in MRI should NOT be used in some patients?

Answer 11

It may cause nephrogenic systemic fibrosis (NSF).

Question 12

Number of joints involved:

Mono:

Oligo:

Pauci:

Poly:

Answer 12

Mono: arthritis

Oligo: 3 or more

Pauci: 5 or more

Poly: 6 or more

Question 13

What nodes are on the DIP in RA?

Which are on the PIP in RA?

Answer 13

DIP - Heberden’s nodes

PIP - Bouchard’s nodes

Question 14

Which GI diseases are associated with arthritis? (3)

Which is associated with reactive arthritis?

Answer 14

UC
CD
Behcet’s disease

Bowel infection

Question 15

What are the arthritis-type conditions that may occur in DM? (2)

What about in thyroid diseases? (1)

Answer 15

Charcot’s joints
Cheirorthropathy

Carpal/tarsal tunnel syndrome

Question 16

What are cytoid bodies and vasculitis seen in?

Answer 16

Retinopathy due to arthritis.