Xanthogranulomatous pyelonephritis: a systematic review of treatment and mortality in >1,000 cases.

Abstract

To systematically review the current demographics, treatment and mortality rate of xanthogranulomatous pyelonephritis (XGP). We hypothesise that the weighted pooled peri-operative mortality rate will be <10%. Searches were performed of Cochrane, Embase, Medline and grey literature for studies published during 01/01/2000-30/08/2021. Eligible studies reported cohorts of ≥10 predominantly adult patients with XGP, and described either average patient age or mortality rate. In total, 40 eligible studies were identified, representing 1,139 patients with XGP. There were 18 deaths, with a weighted pooled peri-operative mortality rate of 1,436 per 100,000 patients. Mean age was 49 years, 70% of patients were female and 28% had diabetes mellitus. The left kidney was more commonly affected (60%). Four patients had bilateral XGP, and all survived. Renal or ureteric stones were present in 69% of patients, including 48% with staghorn calculi. Urine culture was positive in 59% of cases. Fistulae were present in 8%. Correct pre-operative diagnosis occurred in only 45% of patients. Standard treatment continues to comprise a short cause of antibiotics and open radical (total) nephrectomy. Pre-operative decompression occurred in 56% of patients. When considered at all, laparoscopic nephrectomy was performed in 34% of patients. Partial nephrectomy was conducted in 2% of patients. XGP carries a lower mortality rate than historically reported. A typical patient is a female in her fifth or sixth decade of life with urolithiasis. While open radical nephrectomy remains most common, laparoscopic, and to a lesser degree partial nephrectomy are feasible in well selected patients.