61-year-old female patient, referred to the emergency room complaining of left back pain, fever, dysuria and polaciuria seven days ago. It is known to be a carrier of nephrolithiasis and CRD (baseline Cr 2.7 mg / dL) and she is in regular use of sodium bicarbonate and calcium carbonate and also antiretroviral therapy (ART) once she is a HIV positive patient in clinical latency for 23 years showing undetectable viral load. At physical examination demonstrated good general condition, hydrated, afebrile, full pulses, cardiac frequence of 90 bpm, PA 140x90 mmHg, good peripheral capillary perfusion, eupneic, left flank pain. It was requested laboratory tests that revealed: slag elevation (urea: 169 mg / dL and creatinine: 6.32 mg / dL); metabolic acidosis (pH 7.20 and 17 mEq / L HCO3); leukocytosis with neutrophilia (total leukocytes: 16,190 / mm 3 and neutrophils 12,370 / mm 3) and urinary tract infection (UR: pyuria, Gram-negative Gram-negative bacilli and negative BK culture). The imaging study consisted of computed tomography (CT) of the abdomen presented by the patient upon admission to Hospital das Clínicas / UFMG.