Initial plain CT scan showed air in the renal collecting system, ureter and urinary bladder, consistent with emphysematous pyelitis (relatively benign entity).

Follow-up contrast-enhanced CT scan showed mildly enlarged poorly enhancing left kidney, containing multiple focal hypodensities (suggestive of pyelonephritis) and an ill-defined hypodensity containing multiple gas foci at the upper pole, suggestive of emphysematous pyelonephritis; evolving renal abscess can be one possible differential diagnosis of the upper pole lesion.

Despite multiple antibiotics, the patient's condition did not improve and ended up in a nephrectomy. The patient recovered completely after the nephrectomy.