Dx testing

Question 1

What is rheumatoid factor

Answer 1

Antibodies directed against the Fc portion of IgG

Question 2

who is the RF found in most commonly

Answer 2

RA pts

Question 3

a + RF factor correlates w/…

Answer 3

more severe/ more articular dz

Question 4

seronegative RF w/ symtoms…prognosis

Answer 4

better than RF +

Question 5

do titers change with the RF

Answer 5

no

Question 6

can a normal person have + RF

Answer 6

yes, 3%

over 70 = 10-15%

Question 7

when to test RF

Answer 7

Useful in patients who present with an inflammatory polyarthritis
Recognize other possible etiologies of a positive RF
A negative study does not exclude the diagnosis of Seronegative RA
No need to repeat a positive test serially

Question 8

what is Anti-citrullinated peptide antibodyCCP Antibody

Answer 8

Arginine residues are replaced with citrulline

ACPA (Anti-Citrullinated Peptide Antibodies) are directed against a protein that may be critical to the immune response in Rheumatoid Arthritis

Question 9

which is more specific: RF or CCP

Answer 9

CCP

Question 10

CCP antibody interesting facts

Answer 10

may appear before RA symptoms do

related to cig smoking

Question 11

what two tests are used for RA

Answer 11

RF

CCP

Question 12

which is more sensitive/specific for hep c pts: RF or CCP

Answer 12

CCP

Question 13

ANA is + in what % of SLE

Answer 13

99%

Question 14

what is ANA very sensitive but not specific for

Answer 14

SLE

many false +s

Question 15

drug induced + ANA

Answer 15

Procainamide
Hydralazine-htn
Minocycline
Diltiazem
Penicillamine
Isoniazid
Quinidine
Chlorpromazine
Methyldopa
TNF alpha blockers

Question 16

ANA recommendations

Answer 16

99% sensitivity for SLE: Therefore a negative test helps to
exclude SLE
Useful to order in setting of inflammatory arthritis or extra-
articular manifestations of SLE or other connective
tissue diseases
Many false positive tests in the general population
Not useful to monitor disease activity

Question 17

anti DNA anitbody s/s

Answer 17

for SLE very specific but not sensitive, can monitor dz activity

Question 18

anti-sm body

Answer 18

for SLE very specific but not sensitive, cannot monitor dz activity

Question 19

location of Anti-SSA(Ro)/SSB(La) Antibody found

Answer 19

cytoplasm and nucleus

Question 20

+ Anti-SSA(Ro)/SSB(La) Antibody associated with

Answer 20

Associated with Sjögren’s Syndrome (70%)

Question 21

what do you use if the ANA doesnt find an SLE pt

Answer 21

Anti-SSA(Ro)/SSB(La) Antibody

finds the 1%

Question 22

Neonatal lupus syndrome and congenital heart block

• what can you use to test for it
• what is it

Answer 22

Anti-SSA(Ro)/SSB(La) Antibody

If mom has SSA + antibody, babies will be born with a lupus rash (goes away after 6 months) and have very low heart rate (congenital heart block in utero) , may need pacemaker for baby (permanent)

Question 23

what can you use to check for Antiphospholipid Antibodies syndrome

Answer 23

Anti-cardiolipin Ab

Question 24

clinical features of Antiphospholipid Antibodies syndrome

Answer 24

Recurrent venous or arterial thrombosis
Recurrent fetal loss
Thrombocytopenia
Livedo Reticularis
Valvular Heart Disease

Question 25

Anti-neutrophil Cytoplasmic Antibody (ANCA) often found in pts w/

Answer 25

vasculitis

Question 26

c-ANCA

Answer 26

Anti-proteinase 3 antibody (PR3) Associated with Wegener’s (highly specific but not always sensitive) and RPGN Does not always correlate with disease activity

Question 27

p-ANCA

Answer 27

Anti-myeloperoxidase antibody (MPO) Associated with vasculitis, especially microscopic polyangiitis and allergic angiitis and granulomatosis (Churg-Strauss Syndrome)

Question 28

what is sed rate and what is it useful in

Answer 28

Nonspecific test for inflammation Very useful in diagnosis and monitoring of Polymyalgia Rheumatica and Giant Cell Arteritis (almost always high) Sometimes helpful in diagnosis and monitoring of RA, Vasculitis, SLE, Bone and Joint Infections Elevated with Anemia, older age, diabetes, obesity

Question 29

HLA-B27 MC dz associated with it

Answer 29

``` Ank. Spondy. 95% Reiter’s 70% Psoriatic Axial 50% IBD Axial 50% Uveitis 35% Normal Caucasian 8% Normal African American 3% ```

Question 30

Synovial Fluid: Group I

Answer 30

Non-inflammatory conditions such as Osteoarthritis, trauma, endocrinopathies, neuropathic joint, Paget's disease, ischemic necrosis, amyloidosis Pale yellow, transparent, high viscosity WBC is less than 2,000 cells/mm3 usually (low) Negative culture, no crystals

Question 31

Synovial Fluid: Group II

Answer 31

Inflammatory conditions such as Rheumatoid Arthritis, Psoriatic, Spondyloarthropathies, Connective Tissue Diseases, Microcrystalline disease Deeper yellow color, translucent WBC 2,000 - 75,000+ cells/mm3 Cultures negative, crystals found in some

Question 32

Synovial Fluid: Group III

Answer 32

Septic (Bacterial) Purulent, opaque fluid WBC often over 50,000 cells/mm3 (but can be as low as 2,000) with predominance of PMNs (> 90%) Gram stains and cultures are positive

Question 33

Synovial Fluid: Group IV

Answer 33

Hemorrhagic Bloody appearance Due to trauma, neuropathic joints, bleeding disorders, tumors, sickle cell disease

Question 34

Radiology RA

Answer 34

``` Periarticular soft tissue swelling Juxta-articular osteoporosis Uniform loss of joint space Lack of bone formation Marginal erosions Synovial cyst formation Subluxations Symmetrical distribution in certain joints ```

Question 35

Radiology OA

Answer 35

``` Nonuniform loss of joint space Absence of erosions Subchondral new bone formation Osteophyte formation Cysts Subluxation Characteristic distribution ```

Question 36

Psoriatic Arthritis: Radiology

Answer 36

``` Fusiform soft tissue swelling Dramatic joint space loss **“Pencil-in-cup” erosions Often asymmetrical Characteristic joints involved ```

Question 37

Ankylosing Spondylitis: Radiology

Answer 37

Irregularity of Sacroiliac joint Sclerosis of the sacrum and iliac bones Ankylosis with loss of joint space Squaring of vertebral bodies with ivory corners Thin, delicate syndesmophytes leading to bamboo spine

Question 38

Gout: Radiology

Answer 38

``` Tophi Joint space preservation Punched out erosions with sclerotic borders Overhanging edge of cortex Asymmetrical distribution Characteristic joint involvement ```