Incidental detection of purulent fluid in kidney at percutaneous nephrolithotomy for branched renal calculi

Abstract

Background and purpose: Some patients undergoing percutaneous nephrolithotomy (PCNL) have purulent fluid in the pelvicaliceal system at the time of puncture, although preoperative features are not suggestive of infection. We report the management and outcome of 19 such patients.

Patients and methods: Among the 639 patients who underwent PCNL at our center from July 2000 to October 2003, 19 had purulent fluid in the kidney at initial puncture. The preoperative findings, operative details, hospital course, and final outcome in these patients were analyzed. Twelve patients had stone removal at the first sitting (option 1), while seven had a nephrostomy tube placed initially with stone removal deferred for 3 to 7 days (option 2).

Results: With option 1, stones were cleared with one to three tracts in 45 to 120 minutes. Seven patients recovered smoothly, three had transient fever, while one had grade I and another had grade II sepsis. The purulent fluid grew E. coli in two cases and Proteus or Serratia in one case each and was sterile in eight. With option 2, stones were cleared using one to three tracts in 60 to 100 minutes. The fluid grew E. coli or Klebsiella in one case each and was sterile in five. Three patients had a smooth recovery, two had transient fever, one had grade I sepsis, and another had grade II sepsis. Risk factors for sepsis, irrespective of the option, were a recent history of febrile urinary-tract infection, borderline elevation of total leukocyte count, thick or foul pus as opposed to mere turbidity, the use of a single tube or tract or delayed creation of second tracts, and operating time >90 minutes.

Conclusions: Despite normal preoperative urine and blood values, one may find purulence on puncture during PCNL, which is not always infected. If any one or more of the above risk factors is present, it is safer to drain the kidney initially, making sure that all blocked calices are drained, inserting multiple tubes if necessary.