Primary Antibody deficiencies Flashcards
Pathophysiology of XLA?
Bruton tyrosine kinase gene defect leads to arrest of B cells at Pre-B stage
Inheritance of XLA?
30% X-linked (remainder de novo)
What infections occur in XLA?
Encapsulated organisms
Giardiasis
Pyoderma gangrenosum
Enterovirus meningitis (can be fatal)
What is the most common primary immunodeficiency?
IgA deficiency
What is IgA important for in the complement system?
Activates alternate complement pathway
What are the disease associations/complications associated with IgA deficiency (2)?
Crohn’s disease
Celiac’s disease
What is the underlying pathophysiology of hyper-IgM syndrome?
CD40 ligand deficiency - B cells unable to class switch (inc IgM + nil other)
What infections are patient’s with Hyper-IgM at risk of (3)?
PCP
Encapsulated bacteria
Cryptosporidium
What are the two potential long term Cx of Hyper-IgM syndrome?
Hematological malignancy
Bronchiectasis
What is the underlying disorder in CVID?
Antibody deficiency
Why will serological tests not diagnose viral infections in patients with XLA?
Serology relies on finding antibodies within the patient’s serum - need Western blot
What is hyperIgE secondary to?
No Th17 cells
Which particular infections are patients with HyperIgE prone to?
Fungal infections (aspergillus)
What is the half life of IgG?
3 weeks
