Osteolipoma is a very rare histologic variant of lipoma that exhibits bone formation. According to the tumor presentation, endosteal, parosteal, and soft tissue variants are reported. Osteolipoma is an extremely rare tumor. They have been found at various sites, with the highest frequency in head and neck regions. We report a case of parosteal osteolipoma in the left distal femur.

Acute tubular necrosis (ATN) is a syndrome of intrinsic renal injury secondary to ischemic or toxic causes without parenchymal damages and usually non-oliguria. A 20-year old man presented with acute renal failure preceded by 2 days of watery diarrhea. He had been anuria for 48hr with intravenous fluid therapy. Oliguria persisted for 10 days and he required hemodialysis support for 6 days before renal recovery. He denied the use of any regular medication and any intravenous drug use. Renal biopsy revealed severe ATN. Histopathologic findings were marked desquamation of proximal tubular epithelial cells with intact distal tubules and normal glomeruli. We report an unusual case of ATN with anuria and clinically severe features.

Hydroureter could occur in a state where the whole ureter was remarkably expanded. The causes of occurrence are anatomi-cal urinary tract obstruction or vesicoureteral reflux, and it could occur unilaterally or bilaterally according to its reason. A 38-year-old man presented with left flank pain. Abdominal CT showed a severely atrophied left kidney and a large retroperi-toneal cyst near the left kidney. The pathologic finding showed that the cyst wall is composed of transitional epithelium, lamina propria, muscle, and adventitia, and final diagnosis was hydroureter. The unilateral marked hydroureter misdiagnosed as a retroperitoneal cyst was quite rare. We report on this rare case with literature.