<prompt> Hypogonadism with 47 XXY is a feature ofDowns syndromeTurners syndromeEdwards syndromeKlinefelters syndrome  <response>: Ans. d Klinefelters syndrome Ref: Robbins 7th edition, p.179; Harissons internal medicine 17th edition, p. 2317Klinefelter syndrome XXY Common cause of hypogonadism seen in infertility work-up Dysgenesis of seminiferous tubules inhibin FSH. Abnormal Leydig cell function testosterone LH estrogen. Testicular atrophy, eunuchoid habitus, tall, long extremities, gynecomastia, female hair distribution. May present with developmental delay. Presence of inactivated X chromosome Barr body.KLINFELTERS SYNDROME Most common genetic cause of hypogonadism6 Incidence:- 1 in 500 Robbins- 1 in 1000 Harrisionss CF: Eunuchoid body habitat, Atropic testis 3.5 mL r Gynaecomastia, Small penis 2.5 cm Mean I.Q ... Subnormal mental retardation uncommon Semiferous tubules degenerates, Leydig cells are prominent or increased Diagnosis: FSH--with low testestorone and high estrogen level Malignancies: Risk RiskCa. Breast, Ca. Lung, NHL mediastinal, Gonadoblastoma Educational Points:Ca Prostate Testesterone dependentSyndromeAssociated Malignancy Downs SyndromeALL most commonM7 type AMLJuvenile CML Turners SyndromeGonadoblastoma, Ca Colon, Cystic hygroma 