Klinefelter syndrome is the most commonly seen sex chromosomal disorder in males. The typical clinical features of this syndrome are symptoms of hypogonadism in different degrees. Up to 80% of patients with Klinefelter syndrome have 47,XXY karyotype, which is the prevalent type.
Case 1: A 36-year-old male patient applied to our clinic due to the complaint of erectile dysfunction. On physical examination, height was 183 cm, weight 80 kg, and BMI was 23.9 kg/m2. Axillary and pubic hair were present. He had bilateral gynecomastia. Testis volume measured with orchidometer was 20 mL. Karyotype was 47,XXY. In the laboratory examination, follicle-stimulating hormone was 36 mIU/mL (1.27-19.26), luteinizing hormone (LH) 25 mIU/mL (1.24-8.62), and total testosterone was 2.15 ng/mL (2.8-8). Spermiogram demonstrated azoospermia. Intramuscular testosterone treatment was initiated once in three weeks.
Case 2: A 43-year-old male patient applied to our clinic due to the complaints of libido loss and infertility. On physical examination, height was 185, weight was 95 kg, BMI was 27.8 kg/m2, axillary and pubic hair were present, the penis was small, and he had truncal obesity. Karyotype was 47,XXY. Follicle-stimulating hormone was 61 mIU/mL (1.27-19.26), LH 25 mIU/mL (1.24-8.62), total testosterone 0.24 ng/mL (2.8-8), and free testosterone was 3.15 pg/mL (57-178). In bone densitometry, L1-4 Z was -3.5. Intramuscular testosterone treatment was initiated once in three weeks.
In Klinefelter syndrome, testosterone replacement treatment eliminates all negative effects related to androgen deficiency; however, it has no effect on fertility. It should be remembered that Klinefelter syndrome may be detected in infertile males.