Long-term prescribing of nitrofurantoin for urinary tract infections (UTI) in veterans with spinal cord injury (SCI)

Context/Objective: To evaluate the impact of long-term nitrofurantoin for UTI prophylaxis in veterans with SCI. Design: Matched pairs study. Setting: Veterans cared for at VA facilities from 10/1/2012-9/30/2013. Participants: Veterans. Interventions: n/a. Outcomes measures: UTI, positive urine cultures, resistant cultures. Methods: Cases receiving long-term nitrofurantoin (≥90 days supply) were matched to controls by facility. Controls were patients who did not receive long-term nitrofurantoin with a history of ≥3 positive urine cultures and at least one diagnosis of UTI or asymptomatic bacteriuria in the previous year. Results: 122 SCI cases were identified and matched to 196 controls. After adjusting for differences in baseline demographic characteristics, UTIs were less frequent in cases (OR = 0.60 [95% CI 0.44-0.72]). Cases had a greater mean number of days between positive urine cultures as compared to controls (<0.0001). Cases were more likely to have isolates resistant to nitrofurantoin (P ≤ 0.0001); however, the frequency of multi-drug resistant organisms isolated from the urine was not significantly different. Conclusions: Long-term prescription of nitrofurantoin may reduce UTIs in veterans with SCI and there is no evidence that it promotes multi-drug resistance. Future prospective studies should be conducted prior to incorporating routine use of long-term nitrofurantoin into clinical care.