トルコ鞍空洞症に伴った後天性低ゴナドトロピン性性腺機能低下症の1例

Abstract

A 40-year-old unmarried male was referred to our hospital with anejaculation. His secondary sex characteristics, sexual function and ejaculation were previously normal but for the last 5 years he found it impossible to ejaculate even though he could achieve an erection. His genital stage was Tanner V, and pubic hair stage was Tanner III. There were no varicoceles or chromosomal aberrations. His testis volume was 10 ml on the right side and 12 ml on the left. His hormonal data were luleinizing hormone (LH) 0.3 mIU/ml (normal: 2.2-8.4 mIU/ml), fillicle stimulating hormone (FSH) 1.5 mIU/ ml (1.8-12 mIU/ml), testosterone 0.05 ng/ml (2.01-7.5 ng/ml). A gonadtropin releasing hormone (GnRH) test and human chorionic gonadotropin (hCG) stimulation test revealed low responses of LH, FSH and a normal response of testosterone. Magnetic resonance imaging of the head revealed slight depression of the diaphragma sellae, indicating an "empty sella". We diagnosed acquired hypogonadtropic-hypogonadism related empty sella. An hCG replacement therapy was introduced and after 3 months the patient's capacity to ejaculate was restored and testis volume was 14 ml on both sides. Six months after hormone replacement therapy, semen analysis revealed azoospermia. Then we added r-hFSH to his treatment and expect his sperm to reappear.

40歳男。射精障害を主訴に受診し、二次性徴、性機能、射精に異常は認めなかった。直腸診で小さな前立腺を触知し、テストステロンの低値、LHとFSHは基礎値が低く、GnRH負荷試験では低反応を示した。頭部MRIではくも膜下腔がトルコ鞍内へ陥入し、下垂体が鞍底部に圧排されて菲薄化しており、トルコ鞍洞症に伴う後天性低ゴナドトロピン性性腺機能低下症と診断した。hCG自己皮下注射の治療開始後2ヵ月で射精が出現し、6ヵ月後には精液量、精巣容量、public hair stage、テストステロンも改善したが無精子症のためr-hFSH製剤自己注射を追加した。