A case of acute renal failure with multiple origins of the renal injury

Acute kidney injury (AKI) is an abrupt and usually reversible decline in the glomerular filtration rate (GFR). Patients with AKI must be evaluated promptly to determine cause. Different disorders can BE associated with AKI, and biopsy is the most accurate instrument for diagnosis of different types of diseases. We report a case of 69-year-old woman. In history, type II diabetes mellitus and arterial hypertension admitted to our hospital for the evaluation of leg pain, asthenia, diarrhea, and malaise. She was in the treatment with metformin and ARB. Laboratory data revealed renal failure: serum creatinine (Scr 16.5 mg/dl, BUN 280 mg/dl) hyperkalemia and severe anemia (Hb 7.8 g/dl). Renal ultrasound displayed preserved kidneys size. An X-ray of backbone showed fracture. She underwent hemodialysis in urgency regimen. After some days, urine output began to improve up to 1200 cc/24 h. we find proteinuria in nephrotic range. Renal function remained compromised (sCr 8.5 mg/dl, BUN 150 mg/dl). For the evaluation of renal disease, the patient underwent a kidney biopsy. Histological examination findings showed overlapping changes composed of three concurrent pathologic findings: cast nephropathy, diabetes, and light chain deposition disease. After the renal biopsy, therapy with bortezomib, thalidomide, and steroid were administered. At the same time, plasma exchange was carried out. Clinical response occurred with partial recovery of renal function (Scr 3.5 mg/dl eGFR), and dialysis treatment was stopped.