Atypical presentation of xanthogranulomatous pyelonephritis: a case report.

Xanthogranulomatous pyelonephritis (XPN) is a rare form of chronic pyelonephritis, which is usually caused by calculous obstructive uropathy. We present a previously healthy 45-year-old housewife, who was admitted to The Dammam Central Hospital, Dammam, Saudi Arabia with left loin pain and increased frequency of micturition of four days duration. She also had icterus and features of disseminated intravascular coagulation. Abdominal ultrasound and computed tomography of the abdomen was suggestive of XPN. She responded well to treatment with antibiotics and nephrectomy. Histology of the resected kidney confirmed a diagnosis of XPN. Our case suggests that the diagnosis of XPN should be kept in mind when a middle-aged female patient presents with unilateral non-functioning hydronephrotic kidney, which is totally distorted, and has enhancing as well as non-enhancing regions on computed tomography.