Impact of urinary culture on diagnosis and treatment strategy after empiric therapy in febrile neutropenic patients.

Aim: Febrile neutropenia (FN) is treated by a broad-spectrum antimicrobial. Subsequent antimicrobial therapy depends on identifying the source of the infection. Although urinary tract infections (UTIs) are common and urine culture (UC) is a valuable diagnostic tool, uncertainties remain about the specific indications for conducting UC in FN. This study examined whether performing routine UC would affect the subsequent antimicrobial therapy in FN.

Methods: All emergency department patients who received chemotherapy for malignancy and met the definition of FN (neutrophil count <0.5 × 10/L and fever >37.5°C) were included. The patient's demographic data, clinical symptoms, urinalysis results, urine and blood culture results, antibiotic therapy and duration, and patient outcomes were extracted from electronic medical records. UC was defined as positive if >10 colony-forming units/L were detected.

Results: In total, 115 of the initial 124 cases were included in the analysis. Thirty-one cases met the Infectious Diseases Society of America guideline definition for recommending UC (recommended group) and 84 cases did not (non-recommended group). In the recommended group, 16 of 31 cases had a positive UC, and antibiotics were changed for nine, based on UC results. In the non-recommended group, 15 of 84 cases had a positive UC, and antibiotics were changed for two. The same organism were identified in blood cultures. Seven of 115 cases were detected for the same pathogen in blood and urine cultures.

Conclusion: Performing UC regardless of symptoms could diagnose several asymptomatic UTIs in FN, but seldom impact an antimicrobial treatment strategy.