男子不妊を主訴とした染色体異常患者の臨床的検討

Abstract

泌尿器科男子不妊外来を受診した無精子症・高度乏精子症患者のうち, 87名に染色体G band法を施行し, 14名(平均33.5歳)に染色体異常を認めた。内訳は性染色体異常が12名で, Klinefelter症候群(KL)8名, XX male(XX)2名, Y染色体の部分欠損(YQ)1名, マーカー染色体と思われる染色体を持つもの(XM)1名であった。常染色体異常は, 21番染色体短腕11.2と長腕22.3が接合しリング状となった1名と, 1番染色体と10番染色体に転座を認めた1名であった。身長はKLの7名が170cm以上で, 他は170cm以下であった。外性器異常はKLの1名に左停留精巣を, XM例に左精索静脈瘤を認めた。精巣容積はKLとXX例が1～6ccと小さく, 他はおおむね正常であった。血中FSHはYL例と常染色体異常例を除いて高値であった。精巣生検は7名に行い, 精巣内精子は2名に認めた。KLの3名とXXの1名では, 精細管の硝子化とLydig細胞の増殖, Germ cellの欠如を認めた。

A chromosomal survey using the G-banding technique was performed on 87 subfertile male whose semen analysis demonstrated severe oligospermia and azoospermia at Yokohama City University Hospital between January 1990 and October 2002. Fourteen of these subjects demonstrated major chromosomal anomalies (16.1%). Semen analysis in these cases demonstrated azoospermia, except in one case of autosomal abnormality. Twelve patients showed sex chromosomal abnormalities including 8 Klinefelter syndrome (47XXY) and 2 XX males (46XX) and two patients had autosomal abnormalities. The follicle-stimulating hormone (FSH) value in these patients, except for the two cases of autosomal abnormality and one case of 46XYq-, was much higher than normal. Histological examination was performed in 7 cases. In these cases, intratesticular spermatozoa were seen in only two cases (Klinefelter syndrome case and ring chromosome 21 case). Chromosome studies are important in the evaluation of subfertile patients with azoospermia and severe oligospermia. Because the abnormal genotype could be transferred to the next generation, the importance of chromosome studies before ICSI should be emphasized.