SCID Flashcards
What is SCID characterized by?
Severe opportunistic infections such as candidiasis or jiroveci, chronic diarrhea and failure to thrive in infancy
Mostly autosomal inheritance
What is the right form of tx for all SCIDs?
HSCT
Which vaccines should be avoided for SCID diseases?
Live vaccines should be avoided
Which forms of SCID have B cells present?
PNP, deficiency of Jak3 and DiGeorge Syndrome
Which forms of SCID do NOT have B cells?
ADA, RAG1/2 and Artemis deficiency
What is purine nucleoside phosphorylase (PNP) deficiency?
T-B+NK+/-
Normal Ig levels
Accumulation of dGTP which is toxic and leads to a decrease in peripheral T cells but normal B cells
Common autoimmune disorders: hemolytic anemia, thyroid disease, arthritis and lupus
What is deficiency of Jak3?
T-B+NK-
IgM+, low everything else
Mutation in gene encoding for Jak3 leading to a defect in IL-2R signaling
What is DiGeorge syndrome?
T-B+NK+
Normal Ig levels
Deletion of 22q
Classic triad: cardiac anomalies, Hypocalcemia and hypoplastic thymus leading to T cell dysfunction
What is ADA deficiency?
T-B-NK-
Low/absent Ig levels
ADA converts adenosine -> inosine
Mutation leads to accumulation of deoxyadenosine (toxic to lymphocytes)
What is RAG1/2 deficiency?
T-B-NK+
Low/absent Ig levels
Impaired VDJ recombination leading to defective expression of pre-BCR and pre-TCR
What is Artemis decency?
T-B-NK+
Low/absent Ig levels
Rare from of SCID with radiosensitivity
Increased risk of developing lymphomas