Motoyama O, Ohshima M, Shigetomi Y, Ohara T, Nagai Y, Kawamura S, Iitaka K
First Department of Pediatrics, Toho University School of Medicine, Tokyo, Japan.
Nihon Jinzo Gakkai Shi. 1996 May;38(5):233-7.
The proband was a 14-year-old girl with hematuria and proteinuria. Many members of her maternal pedigree had hematuria and proteinuria. Her mother, younger brother (age 12 years) and younger sister (age 9 years) had microscopic hematuria and proteinuria with normal renal function. Her mother had nephrotic syndrome during pregnancy and a renal biopsy was performed. Light microscopic findings of the renal biopsy specimen revealed mild mesangial proliferation and irregularity of glomerular basement membrane. The pedigree showed no chronic renal failure and no deafness. The proband had experienced microscopic hematuria and occasionally macroscopic hematuria since 3 years of age. Proteinuria increased steadily and at the age of 14 years, she had nephrotic syndrome and renal dysfunction (creatinine clearance of 57.9 ml/min/1.48 m2). Renal biopsy was performed and light microscopic findings showed segmental mesangial cell proliferation and numerous interstitial foam cells without significant findings by immunofluorescent study. Electron microscopic examination showed splitting into many layers and thinning of the glomerular basement membrane. She had no complaint of hearing. However, audiological studies detected bilateral low-tone (from 125 Hz to 1000 Hz) sensorineural hearing difficulty, ranging from 30 to 40 dB. High scores on the short increment sensitivity index (SISI) test suggested inner ear hearing difficulty. Audiogram of her brother revealed also low-tone sensorineural hearing loss. Hereditary nephritis with the characteristic lesion of the glomerular basement membrane and sensorineural hearing difficulty has been known as Alport syndrome. Alport syndrome associated with familial low-tone hearing difficulty has not been reported previously.
先证者是一名14岁的血尿和蛋白尿女孩。她母系家族的许多成员都有血尿和蛋白尿。她的母亲、弟弟（12岁）和妹妹（9岁）有镜下血尿和蛋白尿，肾功能正常。她的母亲在孕期患有肾病综合征，并进行了肾活检。肾活检标本的光镜检查结果显示轻度系膜增生和肾小球基底膜不规则。家系中无慢性肾衰竭和耳聋病例。先证者自3岁起就出现镜下血尿，偶尔出现肉眼血尿。蛋白尿稳步增加，14岁时，她患有肾病综合征和肾功能不全（肌酐清除率为57.9 ml/min/1.48 m2）。进行了肾活检，光镜检查结果显示节段性系膜细胞增生和大量间质泡沫细胞，免疫荧光研究无明显发现。电镜检查显示肾小球基底膜分裂成许多层且变薄。她没有听力方面的主诉。然而，听力检查发现双侧低音调（从125 Hz到1000 Hz）感音神经性听力障碍，范围为30至40 dB。短增量敏感指数（SISI）测试得分高提示内耳听力障碍。她弟弟的听力图也显示有低音调感音神经性听力损失。具有肾小球基底膜特征性病变和感音神经性听力障碍的遗传性肾炎被称为Alport综合征。此前尚未报道过与家族性低音调听力障碍相关的Alport综合征。
