Is percutaneous drainage the new gold standard in the management of emphysematous pyelonephritis? Evidence from a systematic review.

PURPOSE: There is no current consensus on what constitutes the ideal management of emphysematous pyelonephritis. We review the current management strategies including the role of nephron preserving percutaneous drainage in the treatment of emphysematous pyelonephritis. MATERIALS AND METHODS: We searched MEDLINE, PubMed, EMBASE, CINAHL and the Cochrane Library from 1966 to 2006. Abstracts were reviewed including all types of studies from prospective randomized controlled studies to small retrospective series. All relevant English language articles reporting on at least 5 patients were reviewed. RESULTS: Ten retrospective studies on 210 patients with emphysematous pyelonephritis met the inclusion criteria. There were 167 females and 43 males with a mean age of 57 years (range 24 to 83). Of the patients 96% had diabetes mellitus and 29% had urinary tract obstruction. The diagnostic accuracy of computerized tomography was 100%. Escherichia coli and Klebsiella were the most common causative agents. The mortality from medical management alone was 50%, medical management combined with emergency nephrectomy was 25% and medical management combined with percutaneous drainage was 13.5%. Mortality was significantly less in patients undergoing percutaneous drainage compared to other treatments (Pearson chi-square p <0.001). Of the patients who underwent medical treatment with percutaneous drainage a small number (15) underwent elective nephrectomy and mortality was 6.6% (1 of 15). CONCLUSIONS: Percutaneous drainage should be part of the initial management strategy for emphysematous pyelonephritis. This strategy is associated with a lower mortality than medical management or emergency nephrectomy. Delayed elective nephrectomy may be required in some patients.