diagnostic

Question 1

proportion of patients w/ positive test results who are correctly diagnosed

Answer 1

positive predictive value

Question 2

what is the current “gold standard” for testing?

Answer 2

indirect immunofluorescence ANA assay

Question 3

what makes for a high negative predictive value?

Answer 3

low disease prevalence because if you have a small amount of people that actually have the disease then the number of negative tests that you have are more likely to be correct

Question 4

what are the acute phase reactants?

Answer 4

ESR, CRP, ferritin, fibrinogen, plateletys

Question 5

what is Antineutrophilic cytoplasmic antibody (ANCA) good for?

Answer 5

really only vasculitis

Question 6

complement tends to be _____ in chronic autoimmune and inflammatory states?

Answer 6

reduced

Question 7

when is ESR most helpuful?

Answer 7

when it is normal so you can rule people out

Question 8

let’s say the RF is negative what does that mean?

Answer 8

you may need to test again because if they arent having an acute flare the body may not be producing IgM

Question 9

is ANA used to monitor disease activity?

Answer 9

no

Question 10

anti-RNP is used for what?

Answer 10

SLE and mixed connective tissue disease

Question 11

percentage of patients w/ the disease who have a positive result

Answer 11

sensitivity

Question 12

probability of correctly identifying a patient WITH a disease

Answer 12

sensitivity

Question 13

percentage of patiens w/o disease with negative test result

Answer 13

rare false positives

Question 14

most useful when positive

Answer 14

specificity

Question 15

C3 and C4 are useful in monitoring?

Answer 15

SLE patients

Question 16

ANA is has high ____ but low ____

Answer 16

sensitivity, specificity

Question 17

ANA tests

Answer 17

1:80

Question 18

anti-SM or smith is specific for what?

Answer 18

SLE

Question 19

what is rheumatoid factor?

Answer 19

IgM autoantibody directed against the Fc (heavy chain) portion of the IgG

Question 20

what is the diagnostic test for lupus?

Answer 20

anti-dsDNA

Question 21

rare false negative, but increased false positives

Answer 21

sensitivity

Question 22

anti-Ro (SS-A) and anti-La (S-B) are used for what?

Answer 22

SLE or Sjogren’s (especially for SICCA?) dry eyes and dry mouth

Question 23

anticentromere antibodies is seen in what?

Answer 23

cleroderma specifically the CREST variant

Question 24

probability of correctly identifying a patient without the disease

Answer 24

specificity

Question 25

anti-dsDNA does not occur in ___?

Answer 25

drug induced lupus except for

1. penicillamine
2. minocycline
3. antitumor necrosis factor

Question 26

anti-Ro and anti-La are important for mother’s why?

Answer 26

because the child can have neonatal cutaneous lupus that leads to complete heart block

Question 27

number of new diagnoses that have occured in a specific time interaval in a specific population

Answer 27

incidence

Question 28

what is the anti-CCP good for?

Answer 28

highly specific for RA, better than RF for RA, but together (RF-anti-CCP) almost 100% they have RA