Ataxia Telangiectasia - Immunology USMLE Step 1

Ataxia Telangiectasia - Immunology USMLE Step 1: Defects in ATM gene  failure to detect DNA damage  leading to halt progression of cell cycle  mutations accumulate autosomal recessive Triad: cerebellar defects (Ataxia), spider Angiomas (telangiectasia), IgA deficiency  extremely increased sensitivity to radiation (limit x-ray exposure) FINDINGS: Increased AFP Decreased IgA, IgG, and IgE Lymphopenia, Cerebellar atrophy Increased risk of lymphoma and leukemia