Diagnostic methods of Rheumatic diseases

Question 1

How to differentiate between SLE and MCTD after ANA test with immunofluorescence showing a Homogeneous pattern?

Answer 1

Ds DNA immunoglobulin testing
(present in SLE)

Question 2

A patient comes with an autoimmune disease yet to be known, ANA testing shows a nucleolar pattern on immunofluorescence which means the patient has either SLE or Scleroderma, what is the next step?

Answer 2

Do an ENA test to detect Scl-70 antibodies, (present in scleroderma and absent in SLE)

Question 3

A patient is diagnosed with myositis, in the ANA test, the immunofluorescence shows a specific pattern, what is that pattern?, what is the antibody recommended to test for?

Answer 3

A cytoplasmic pattern
AB: Anto Jo-1

Question 4

A patient is diagnosed with scleroderma, in the ANA test, the immunofluorescence shows a specific pattern, what is that pattern?, what is the antibody recommended to test for?

Answer 4

A centromere pattern,
Ab: anti Scl-70

Question 5

How to differentiate between diffuse and limited cutaneous scleroderma using antibodies?

Answer 5

Diffuse type: anti-Scl-70
Limited type: anticentromere

Question 6

What are the antibodies detected in serology of cases of vasculitis?

Answer 6

ANCA

Question 7

What is the difference between ANCA-P AND ANCA-C

Answer 7

Both attack specific antigens in thecytoplasm;
P-ANCA: attacks MPO (myeloperoxidase)
C-ANCA: attacks proteinase-3 (PR3)

Question 8

What is the type of ANCA aasociated with Wegener’s granulomatosis?

Answer 8

P-ANCA