MSFinals-1072

MSFinals-1072

A 16-year-old male presents with delayed pubertal development and a history of impaired sense of smell. He has a height on the 90th centile and weight on the 95th centile. There is no pubertal development in his external genitalia and his testicular volumes are 3 mL bilaterally. Upon investigation, his plasma luteinising hormone and follicle stimulating hormone levels are both 1.0 U/L (1-10), while his serum testosterone level is 2.0 pmol/L (9-33). His free T4 level is 20 pmol/L (10-22) and his plasma thyroid stimulating hormone level is 3.2 mU/L (0.4-5). A CT brain scan shows no abnormalities. What is the most likely diagnosis?