Clinical Serology, Lab Testing, & Gout/Pseudogout Flashcards Preview

MSK II Exam II > Clinical Serology, Lab Testing, & Gout/Pseudogout > Flashcards

Flashcards in Clinical Serology, Lab Testing, & Gout/Pseudogout Deck (49)
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1

Acute phase reactant that is a marker of inflammation

Rises with age, higher in women, and monitors disease activity

ESR

2

ESR is utilized to monitor disease activity, especially _____ and ______

Polymyalgia rheumatica; giant cell arteritis

3

CRP is an acute phase reactant that is a marker of inflammation and is utilized as an assessment of disease activity.

It is synthesized in the ______. Proinflammatory ______ increase the CRP.

CRP can also activate ______ and promote phagocytosis

A CRP reading of >8 mg/L is inflammatory

Liver; cytokines

Complement

4

T/F: ESR rises and falls more quickly than CRP

False; CRP rises and falls quicker than ESR

5

Examples of general inflammatory markers other than ESR and CRP

Leukocytosis
Thrombocytosis
Ferritin
Fibrinogen
Complement (decreases)

6

IgM autoantibody that targets the Fc portion of IgG immunoglobulin

Rheumatoid factor

7

RF is produced by _____ cells in ______ joints of RA pts

B cells; synovial

8

RF is present in 70% of pts with RA, and is present in 100% of pts with _______ RA

Nodular

9

Besides RA, what conditions might reveal a positive RF?

Sjogrens syndrome
Cryoglobulinemia
Primary biliary cirrhosis
Mixed CT disease
Endocarditis; chronic infections
SLE
Sarcoidosis
Malignancy
Lung disease

10

The cutoff value for positive RF depends on lab method; positive RF > 45 IU/mL by ELISA or >1:80 by latex fixation.

Higher RF levels are correlated with what features of the inflammatory disease process?

High levels associated with more aggressive disease, joint erosions, and worse px

11

_______ antibodies are present in 70% of pts with early RA and have more specificity characteristics of RA than RF

Anti-cyclic citrullinated peptide (anti-CCP)

12

______ antibodies + _____ = 99.5% specificity for RA

Anti-CCP; RF

13

Antibody directed against nuclear antigens; may be found in normal pts as well as those with RA, CTD, malignancy, etc. (nonspecific!!); pattern of immunofluorescence gives clues to dx

Anti-nuclear antibody (ANA)

14

Homogenous ANA pattern

Histone antibody — 95% of drug-induced lupus

15

Rim pattern of ANA

Anti-dsDNA — 50% SLE

16

Speckled ANA pattern

Anti-Sm (smith) — lupus

Anti-SS-A/SS-B — Sjogren

17

________ and _____ antibodyies are associated with scleroderma CREST/progressive systemic sclerosis

Anticentromere; anti-scl 70

18

Hematologic criteria/findings in SLE

Hemolytic anemia with reticulocytosis

[or]

Leukopenia (<4000/mm3 total)

[or]

Lymphopenia (<1500/mm3) on 2 or more occasions

[or]

Thrombocytopenia (<100,000/mm3)

19

Immunologic findings associated with lupus

Anti-DNA Abs

Anti-Sm

Antiphospholipid antibodies (IgG or IgM cardiolipin Abs)

Positive lupus anticoagulant

False positive RPR (syphilis test)

ANA

20

What is the significance of a positive antistreptolysin O antibody (ASO) and/or anti-DNAase B titer?

Evidence of a preceding group A streptococcal infection

[Clinically may see acute rheumatic fever, polyarticular asymmetric arthritis of large joints, may cause post-streptococcal reactive arthritis (symmetric and affects small joints)]

21

A 46 y/o male presents with fatigue, malaise, pain in both wrists, and bilateral swelling over MCP joints. He admits to previous hx of lupus. The symptoms have been present for 6 weeks. PE reveals decreased strength in both hands, swollen wrists, PIPs, and MCP joints bilaterally, and a nodule on the extensor surface of the left arm. Which lab test would you expect to be abnormal in this case?

A. CBC indicating hemolytic anemia, leukocytosis, and negative RPR
B. Low complement C3, decreased ferritin, and elevated platelet count
C. Positive anti-CCP, elevated ESR, and elevated RF level
D. Positive ANA, negative RF, and elevated CRP
E. Thrombocytosis, hypocalcemia, and normal ESR

C. Positive anti-CCP, elevated ESR, and elevated RF level

22

Hyperuricemia is defined as a uric acid > _______ mg/dL that may be due to overproduction or underexcretion of uric acid. It is associated with development of gouty arthritis which consists of ___________ crystals in joint fluid or tophi.

Crystals are needle-shaped, ______ birefringent by polarized light microscopy.

Attacks are acute in onset, monoarticular, often the 1st MTP joint (_______). Often nocturnal awakening.

6.8; monosodium urate

Negative

Podagra

23

Nodular deposits of monosodium urate crystals in skin

Tophi

24

90% of gout cases are in men (4th-6th decade) or ________ women

Post-menopausal

25

________ and ______ are dietary risk factors that promote increased urate production and decreased excretion

Alcohol; red meat

26

Acute vs. chronic gout tx

Acute:
NSAIDs
Colchicine (GI toxicity)
Steroids

Chronic:
Xanthine oxidase inhibitor
Uricosurics
Probenecid — blocks tubular resorption of urate and increases uric acid excretion

27

Imaging study that may not detect early erosive arthritic disease but may show symmetrical involvement of MCPs in RA, periarticular osteopenia (decreased bone mass, bone loss), and erosions

Plain radiography

[digital radiographs have high spatial resolution but have poor visualization of soft tissue]

28

Imaging study that is sensitive for soft tissue abnormalities like synovitis, tendonitis, bursitis, as well as evidence of joint erosions

May aid in injecting/aspirating joint, and do not involve radiation

Ultrasound

29

Imaging study useful for soft tissue abnormalities; utilizes gadolinium contrast which is taken up in inflamed synovium (thickened pannus) but contrast may cause nephrogenic systemic fibrosis in pts with renal disease

Good modality for spine, SI, synovitis, tenosynovitis, erosions, and joint inflammation

MRI

30

Best imaging study for bony abnormalities (trabecular, cortical bone), erosions, fractures, degenerative or inflammatory arthritis

CT

31

Which is more sensitive for bone erosions — MRI or CT?

CT

32

A 50 y/o carpenter presents with pain, swelling, and decreased ROM in the right elbow. The elbow is swollen and very tender to touch. He relates to doing a lot of hammering, lifting boards, and sawing. Which imaging study is indicated in evaluation of the pts complaint?

A. CT of right arm — att.elbow
B. Plain X-rays of elbow
C. MRI right arm — att.elbow
D. US — att.elbow
E. Bone scan — att.elbow

D. US — att.elbow

33

Criteria for categorizing arthritis

Duration
# of joints
Symmetry
Distribution
Inflammation
Type of swelling
Systemic signs
Extra-articular dz
Age of pt
Nocturnal pain
Enthesopathy
Response to prior treatment
Labs and other tests

34

GI diseases/syndromes associated with arthritis

UC
Crohns
Behcets

Reactive arthritis with bowel infection

35

Arthritis manifestations associated with diabetes

Charcot’s joint = gross deformity often affecting ankle or foot in diabetic pt with clinical features including loss of sensation, loss of proprioception, and increased susceptibility to infection

Cheiroarthropathy — arthritic pain, tightness/thickening of skin due to extra collagen buildup

36

Joint manifestations of thyroid disease

Carpal/tarsal tunnel syndrome

37

Cytoid bodies and vasculitis are associated with what ophthalmologic manifestation?

Retinopathy

38

2 main complications of chronic gouty arthritis

Tophi (ears, forearms, achilles tendon)

Renal insufficiency (radiolucent urate stones)

39

Asymptomatic hyperuricemia should not be treated. What is the one exception?

Pt about to receive cytotoxic therapy for a neoplasm

40

2 xanthine oxidase inhibitors

Allopurinol
Febuxostat

41

2 drugs that inhibit inflammation caused by crystal precipitation and joint inflammation in acute gout

NSAIDs (naproxen, indomethacin)

Colchicine

42

Urinary excretion of uric acid can be promoted by what drug?

Probenecid

43

Oral, parenteral, or intra-articular _____ can be a reasonable first line tx in acute gout; caution in HF, HTN, poorly controlled DM, sepsis, and CKD pts

Steroids (prednisone)

44

Gout tx effective within 1st 24 hrs of atack; side effects are usually GI — N/V/D

Colchicine

45

IL-1B antagonist (biologic) that may be administered subcutaneously to tx gout

Anakinra

46

Indications for uric acid lowering agents

Recurrent gouty attacks, tophi, renal stones, cytotoxic chemotherapy

[DO NOT start during acute attack — can precipitate flare; DO NOT use with CKD or stones]

47

Pseudogout (Calcium pyrophosphate dehydrate deposition disease) typically affects larger joints, particularly the _____, in older pts. It can be polyarticular and presents similarly to gout. If chronic, it can resemble ______.

A complication is _____ which is calcium deposits in articular cartilage. Treatment is similar to true gout

Knee; OA

Chondrocalcinosis

48

Short blunt rods, rhomboids/cuboids and weak positive birefringence by polarizing microscopy

Pseudogout

49

Pseudogout (CPPD) is associated with aging. If it is found in younger pts, what are some diseases to consider?

Primary hyperparathyroidism

Hemochromatosis

Hypomagnesemia

Chronic gout

Gitelman’s syndrome