Objective: The aim of this study was to evaluate the efficacy of percutaneous nephrostomy (PCN) drainage for the interim management of pyonephrosis.
Methods: Ninety-two consecutive patients [29 men, 63 women; mean age, 57 years; range, 23 to 88] who underwent PCN for the treatment of pyonephrosis from 1996 to 1999 were evaluated retrospectively. The clinical presentation, bacteriology and patient outcomes were analyzed.
Results: The majority [77%] of patients had underlying obstructing urinary calculi. Other causes of obstruction included strictures [9%], papillary necrosis [7%], pelvi-ureteric junction obstruction [4%] and malignant stricture [3%]. The microorganisms cultured were Escherichia coli [30%], Klebsiella [19%], Proteus [8%], Pseudomonas [5%], Enterococcus [5%], and Candida spp [5%]. The microorganisms were sensitive to gentamicin [79%], ceftriaxone [71%], cephalexin [54%], nitrofurantoin [40%], cotrimoxazole [35%], nalidixic acid [32%] and ampicillin [29%]. Only 30% of bladder urine cultures were positive for microorganisms; the addition of PCN cultures improved this yield to 58%. The antibiotic regimen was revised according to the PCN culture whenever there was a discrepancy. After PCN, 69% of patients underwent minimally invasive procedures as definitive treatment of the obstructing lesion. Only 14% of patients required open surgery. There was low procedure-related morbidity [14%] and low overall mortality [2%].
Conclusions: PCN cultures yield important bacteriological information. The procedure is associated with minimal morbidity, facilitates definitive treatment and provides therapeutic benefit.