Urinary pH, Methenamine, and Formaldehyde Levels in the Management of Postmenopausal Women With Recurrent Urinary Tract Infections: A 1-Year Prospective Pilot Study With Extended Follow-up.
Academic Article
Overview
abstract
OBJECTIVE: To evaluate urinary pH, methenamine (uME), and formaldehyde (uFA) levels from women with documented recurrent urinary tract infections (rUTIs) taking Hiprex and monitored these levels with rUTI incidence over time. METHODS: Following IRB-approval, non-neurogenic women, ages 50-85 years old, with a history of rUTIs, low urinary pH trends (<6), and interested in being monitored for UTI symptoms while taking Hiprex for 1 year were enrolled at a tertiary care center specializing in rUTI management. At the initial and six subsequent office visits, a urine sample was obtained prior to, and 1 hour after, taking 1 gm Hiprex. Urine pH, uME, and uFA levels were measured using commercially available kits, normalized to urinary creatinine. RESULTS: Of 29 patients (mean age 71.4 years) screened, seven met study criteria and completed the 1-year study, with an additional year of follow-up. Methenamine was identified in the urine of each participant after Hiprex administration. Median uFA levels increased between 14% and 130% 1-hour following Hiprex administration. Most individuals (71%) consistently had a urine pH below 6. The majority remained UTI-free. CONCLUSION: This study confirmed the durable presence of uME and uFA from those on Hiprex in a low urinary pH environment with clinical efficacy. A sustained increase in uFA was observed 1-hour following office-administered Hiprex. The uFA concentration was lower than deemed bactericidal in vitro; so, additional research is needed on the mechanism of Hiprex to better define its role in UTI prevention.
