Emphysematous Pyelonephritis (EPN) is an uncommon but life-threatening condition for which diabetic patients are at high risk. The most common chief complaint bringing patients to the hospital is upper urinary tract infection. Early clinical diagnosis with radiography is a key to reduce the complications and death due to emphysematous pyelonephritis. We present a case study of a 45-year old female patient who was presenting to the emergency room with left flank pain. Blood testing showed acute kidney injury, E. coli bacteremia, and the radiography demonstrated an abnormal image of the left kidney consistent with EPN. Symptomatic treatment and antibiotic were given, but no response and developed to heart failure and death at Emergency Room.