Rheumatology: Autoimmunity and SLE

Question 1

Organ specific autoimmunity examples?

Answer 1

myasthenia gravis
Goodpasture
autoimmune thyroiditis
type I DM

Question 2

What is the specific marker for SLE?

Answer 2

there is none

Question 3

4/11 of these criteria must be met to diagnose SLE:

Answer 3

1. malar rash 2. discoid rash 3. photosensitivity 4. oral ulcers 5. arthritis 6. serositis 7. renal involvement 8. CNS involvement 9. hematologic disorders 10. immunologic disorders 11. ANA

Question 4

What does ANA stand for?

Answer 4

antinuclear antibody

Question 5

Who does SLE affect?

Answer 5

women>men, age of onset: puberty-childbearing years, African, Asian, Hispanic; increased among relatives and monozygotic twins

Question 6

What are the 2 genetic associations in SLE?

Answer 6

C4A null alleles and HLA-DR3

Question 7

How does IFN play a role in SLE?

Answer 7

interferon alpha and beta (IFN signature) is prevalent in active SLE

Question 8

How does sun exposure affect SLE?

Answer 8

causes exacerbations

Question 9

Organ damage in SLE can be from type ____ or type ____ mediated immunologic damage.

Answer 9

II or III

Question 10

What are the type II mediated presentations of SLE?

Answer 10

Hemolytic anemia (IgG and complement on RBCs), antiphospholipid antibodies (elevated PTT and increased clotting), CNS manifestations (autoantibodies that bind to neurons)

Question 11

What are the type III mediated presentations of SLE?

Answer 11

lupus nephritis, antibodies to dsDNA and complement activation

Question 12

____ are the hallmark of abnormal Ab production in SLE.

Answer 12

ANAs

Question 13

How are ANAs detected in SLE?

Answer 13

indirect immunofluorescence assay

Question 14

Specific antinuclear antibodies can be made to ____, _____, and ____ in SLE.

Answer 14

DNA, histones, non-histone/non-DNA nuclear antigens

Question 15

What is lupus nephritis?

Answer 15

kidney/glomerular abnormalities bc of immune complex deposition and Abs to dsDNA; also activates complement

Question 16

What are ANAs?

Answer 16

antinuclear antibodies (Abs to DNA, RNA, histones, or others)

Question 17

How are ANAs measured?

Answer 17

radioimmunoassay (RIA), ELISA, immunoprecipitation

Question 18

In SLE, the clearance of _____, ______, and ______ also appears to be defective.

Answer 18

immune complexes, apoptotic cells, cell debris

Question 19

Name 5 theories to autoimmunity in SLE.

Answer 19

1. polyclonal B cell activation
2. molecular mimicry
3. illicit help (combined foreign/autoantigen)
4. sequestered antigen
5. immunodeficiency (deficient C1q, C4, C2, Fc receptor)

Question 20

How is SLE treated?

Answer 20

decrease exposure to triggers (sunscreen), decrease inflam. response (NSAIDs and corticosteroids), decrease cellular/humoral response (anti-malarials, immunosuppressives), anti-B cell therapy (belimumab), IVIG