[Stone-containing pyelocaliceal diverticulum: a case report].

We report a case of stone-containing pyelocaliceal diverticulum. A 68-year-old man was admitted for extensive investigation of microscopic hematuria on January 12, 1983. A cluster of numerous small calcifications was disclosed in the left renal region on an abdominal plain film and the case was considered to be of stones in the left kidney. An excretory pyelogram showed that the stones were away from the collecting system of the left kidney. Through partial nephrectomy, 107 stones were removed on January 21, 1983. Histological examination of the surgical specimen revealed pyelocaliceal diverticulum. The stones were found to consist of calcium oxalate and calcium phosphate by infrared spectrophotometry. In addition to these components, a small amount of magnesium was detected by X-ray microanalysis. A scanning electron microscopic study of the cut surface of the stones disclosed the presence of a granular core identified as urate and calcium oxalate, concentric laminations of crystallized substances in the mid-zone and laminations of amorphous substances in the outer layer.