[Infected solitary renal cyst extending to subphrenic abscess--a case study and review of the literature].

A 54-year-old female, who had been mediated for simple type schizophrenia for the past eleven years, was hospitalized with left lumbar discomfort or pain. After admission, the following abnormalities were apparent serologically; leucocytosis of 15700/mm, erythrocyte sedimentation rate of 147 mm/h, hyper alpha 2-globulinemia (675 ng/dl of haptoglobulin). Urine cultures were negative. Left renal simple cyst with infection was evaluated by intravenous urography, ultrasonogram, computed tomographic (CT) scan., and renal angiogram. In addition, left subphrenic abscess behind the spleen, which had to be penetrated through retroperitoneum, could be diagnosed. So, in our case, cystic wall resection (unroofing) and/or conservatively percutaneous cystotomy for pus drainage were all not indicated instead of radical operation for abscess removal completely. CT scan is mostly available to make differential diagnosis whether the infectious renal cyst influence to the neighbouring organs beyond the renal capsule, or not. Here, we discussed the pathogenesis on the infection of solitary renal cyst, and some problems reported in the literature.