In normal male, puberty is characte

In normal male, puberty is characterised by increased size of testis, increased penile length, spermatogenesis and appearance of secondary sexual characteristics under the influence of testosterone. We found small genitalia, absent secondary sexual characteristics and infertility the major presenting features which indicate pubertal deficiency of testosterone. Patients with total testosterone level less than 300 ηg/dL usually have signs and symptoms of classic hypogonadism.1 In our study hypogonadotrophic hypogonadism was present in 86% of patients and majority among them had IHH defined as pubertal delay at 18 years of age or older, low testosterone level with low/normal FSH and LH levels and no pituitary or hypothalamic lesion. IHH is a disorder caused by genetic defect in biosynthesis and secretion of GnRH by hypothalamus or its action on pituitary. It is five times more prevalent in men.7 Two thirds of patients with isolated GnRH deficiency have anosmia/hyposmia (called Kallman syndrome) and one third have normal sense of smell.8 Most cases of Kallman syndrome are sporadic,9 but familial occurrences is also observed. In our study, among hypogonadotrophic hypogonadism patients 3 had Kallman syndrome. Specific genetic mutations, i.e., DAX-1, KAL-1, FGFR1, GPR54, Prop-1, and Hesx1, have been identified causing hypogonadotrophic hypogonadism.