Syndrome associated with thymic and parathyroid hypoplasia:

Ans: c (Di George syndrome) Ref: Harrison, 16th ed,p. 1942; Nelson, 17th ed, p. 211, 694,735Di George syndrome is characterized by variable loss of T cell mediated immunity (due to hypoplasia of thymus), tetany (due to lack of parathyroids) and congenital defects of heart and great vessels.Di George syndromeIt is a syndrome of isolated T cell deficiency. Most commomn microdeletion syndromeMaldevelopment of thymic epithelial elements derived from 3 rd and 4th pharyngeal pouch there is deletion of short piece of long arm of chromosome 22 (22q 11) Autosomal dominant/ sporadicIt is also called Velocardiac facial syndrome.The acronym is CATCH-22C - Cardiac defectsA - Abnormal faciesT - Thymic hypoplasiaC - Cleft palateH - Hypocalcemia from parathyroid hypoplasia22 - Microdeletion chromosome 22