糸球体基底膜にびまん性の菲薄化を示した進行期アルポート症候群の1例

Abstract

A 16-year-old boy was admitted to our department because of facial and pretibial edema. Laboratory data revealed moderate renal impairment (Ccr 36.8 ml/min), hypoalbuminemia (2.5g/dl), and hypercholesterolemia (303mg/dl). Audiometry demon- strated bilateral and high tone sensorineural deafness. Renal biopsy showed mesangial proliferation, diffuse tubulo-interstitial damage, and clusters of foam cells. Electron microscopic examination disclosed splitting of the glomerular basement membrane (GBM). Most of the GBM was thin; about 200 nm or less in thickness. Lack of collagen Ⅳ α 5 chain was confirmed by using monoclonal antibody to collagen Ⅳ α 5 chain. Accordingly, the patient was diagnosed as having advanced stage of Alport's syndrome (type Ⅲ) associated with nephrotic syndrome. In general, patients with advanced Alport's syndrome show diffuse thickening of the GBM. Therefore, we think that this patient is an unusual case of clinically advanced Alport's syndrome exhibiting diffuse thinning of the GBM. Here we report the details of this case and discuss the relevant literature.