Exam 1 Diseases Flashcards
Hypogammaglobulinemia
Low level of antibodies
Agammaglobulinemia
No antibodies
XLA
- X-linked (Brutons) agammaglobulinemia
- mutation on X chromosome Xq21.3-q22
- deletion/mutation of bruton’s tyrosine kinase (BTK)
- No B cells made
CVID
Normal B cell count, but no plasma cells
Diagnosis made by IgG and IgA level more than two standard deviations below the norm
Wide range of causes (can be B or T cell related)
Hyper IgM syndrome
normal B cell number, more IgM antibodies
No IgG/A/E
Three main forms - only one in red is X-linked hyper-IGM (Type I)
Selective IgA deficiency
most asymptomatic due to IgM compensatory effect
Most common immunodeficiency
How common is selective IgA deficiency
1:500
XL-SCID
- IL-2 receptor required for B/T cell development
- forms part of IL-7R
- Non-functional IL7 (thymus)
- Serology abnormal for T cells
- Males more commonly affected
DiGeorge syndrome
- thymic aplasia (congenital absence of thymus)
- 22q11.2 deletion syndrome
- cleft palate, craniofacial disorders
- TBX1 gene in pharyngeal pouches is affected
- complete deletion = absence of thymus
Bare Lymphocyte syndrome is associated with:
MHC complex genes
BLS1
MHC class I deficiency - mutations of TAP1, no normal protein complex with MHC 1
intracellular parasites, viral infections
BLS2
MHC class II deficiency - no found antigens complex with MHC II
Form of SCID (Th1 and 2 are not functional)
Heterotaxy syndrome
internal thoracic abdominal organs exhibit abnormal arrangements across left-right axis
Asplenia heterotaxy syndrome
missing spleen entirely - major site of antibody production
Polysplenia heterotaxy syndrome
multiple small accessory spleens with reduced function - thymus may be affected
