In Reply.

Abstract

We thank the authors1 for pointing out the similarities in our findings. To clarify, our study design was a retrospective review of symptomatic female patients presenting to the emergency department (ED) with acute uncomplicated cystitis while the study by Gangcuangco et al. was prospective. We did not include diagnoses of pyelonephritis. The hospital-wide antibiogram we used for comparison included all Escherichia coli isolates cultured at our institution from urinary and nonurinary sources, as is customary in most U.S. hospital antibiograms. These cultures also included culture data from other outpatient areas but the data were not compared from the outpatient versus inpatient settings. In our study we compared urinary isolates that were sent for culture reflexively if the urinalysis was abnormal in any way. In most cases these cultures were not ordered by the physician. We did not have the luxury of an “ED-specific antibiogram,” but we did have susceptibility data in cases of cystitis where the standard of care is not to obtain urinary cultures. In fact ED-specific antibiograms may not be the answer, since these E. coli cultures could include pathogens isolated from patients with complicated urinary tract infections and urosepsis. One might expect these isolates to be less susceptible to antibiotics than the results displayed in the hospital antibiogram. This idea is confirmed if one compares E. coli culture data from the 2014 hospital antibiogram to the data from the medical intensive care unit (MICU). Susceptibilities for E. coli in the MICU were 60 and 47% for trimethoprim/sulfamethoxazole and ciprofloxacin, respectively, compared to 67 and 69% for the hospital antibiogram. The finding of greater TMP-SMX resistance in the Philippines is interesting and predictable given the availability of this agent without a prescription. Undoubtedly, many nonbiologic factors, such as antibiotic availability, prescribing patterns, and cost, affect resistance patterns in any population. This supports our assertion that resistance patterns vary by location and time and also reaffirms the need for dynamic and specific antimicrobial recommendations based on the population being treated. At our institutions, common infections such as uncomplicated cystitis are routinely treated empirically and successfully without culture data. However, the “laboratory-based passive microbiologic surveillance” system described by the authors could be used to monitor changes in susceptibility patterns should further studies determine that this is cost-effective.