Authors' Response to Bozkurt et al.

To the Editor:

We thank Dr. Bozkurt and colleagues for their knowledgeable comments on our study. Three questions were raised regarding the role of positive stone cultures in the definition of sepsis, preoperative antimicrobial prophylaxis, and decompression of the obstructed collecting system.

Our definition of sepsis did not utilize stone culture positivity because of the unlikelihood that a solely positive stone culture in the absence of positive blood and/or urine cultures is not pathogenic in a patient with Systemic Inflammatory Response Syndrome (SIRS). The bacteria in this scenario are surviving on a biologic scaffolding apart from the parenchyma. We also note that stone cultures can take longer to return a positive result and may only grow in a broth medium after many days of incubation. In these circumstances, it is unlikely that the organism would be the cause of a pathogenic response (SIRS or sepsis).

The utilization of preoperative antimicrobial prophylaxis has been the source of much debate. However, we note that our sepsis rate was extraordinarily low at <1% and previous publications have noted a low rate of adverse events with antimicrobial prophylaxis. ¹ A prior prospective investigation has identified 1 week of antimicrobial prophylaxis to prevent urosepsis. ² In the absence of level 1 evidence, which the American Urological Association (AUA) best practice statement does not provide, our practice has been to give 1 week of antibiotics preoperatively.

Lastly, there were questions regarding the decompression of an obstructed collecting system within the study. All patients who were decompressed had signs and symptoms of obstruction. Although hydronephrosis may be present in an obstructed system, it is only an imaging finding, and clinical signs of obstruction (i.e., pain and worsening renal function) were also utilized when making the decision to decompress patients.