Comlpement Deficienices

Question 1

Describe deficiencies of the CP

Answer 1

Primary C1 and C4 deficiency linked to SLE or RA
C2 deficiency is most common in caucasians(especially in young children who end up having recurrent infections with streptococcus pneumoniae)

Question 2

Describe MAC deficiencies

Answer 2

Deficiency of late proteins (C5-9) lead to increased susceptibility to Neisseria infections
The cause of low C8 may be due to inherited deficiencies, acquired deficient or complement consumption

Question 3

If C8 levels are absent in the presence of C3 and C4, what is this consistent with?

Answer 3

C8 deficiency

Question 4

If C8 levels are absent along with low C3 and C4, what is this consistent with?

Answer 4

Complement consumption

Question 5

Describe deficiencies of C1-INH

Answer 5

Causes HAE
Production of bradykinin is the cause of swelling in these pts
Tx= C1-ING replacement therapy

Question 6

Describe PNH

Answer 6

Deficiency of GPI anchor proteins DAF (CD55) and CD59 which protect RBCs from complement

Question 7

Describe deficiencies of TLRs

Answer 7

MyD88 deficiency results in impaired signaling for all TLRs except for TL3 (MyD88 independent)
Leads to abnormally frequent and severe infections caused by pyogenic bacteria but normal resistance to other pathogens

Question 8

What do pts with MyD88 deficiency characteristically lack?

Answer 8

They lack elevated ESR/CRP and fever during an active infection

Question 9

What does TL3 deficiency result in?

Answer 9

Increased susceptibility to HSV encephalitis