Klinefelter syndrome presenting as behavioral problems in a young adult.

BACKGROUND: An 18-year-old Somali man presented to a primary care clinic to investigate a potential pathophysiological reason for behavioral problems at school that had arisen in the past 1-2 years. A previous physical examination at school revealed the patient to have small, firm testicles which prompted further testing. INVESTIGATION: Thyroid function and levels of prolactin, total testosterone, follicle-stimulating hormone and luteinizing hormone were determined. Testes were measured. Chromosome analysis testing was performed to determine the patient's karyotype. DIAGNOSIS: Klinefelter syndrome with a 47,XXY karyotype. MANAGEMENT: Testosterone replacement therapy was recommended, but the patient declined treatment.