Background Recurrent urinary tract infections (UTI) are an important cause of morbidity and mortality in renal transplant recipients (RTR). Methods In this retrospective study we gathered clinical data from patients prescribed methenamine hippurate to prevent recurrent UTI pre‐ and post‐intervention. Thirty‐eight RTR ≥18 years old at Northwestern Memorial Hospital from 2006‐2017 were included in the final analysis. Results The median and range for follow‐up days were 365 (299‐365) pre‐ vs 314 (105‐365) post‐methenamine. Total UTI frequency (9.16 vs 5.01/1000 patient follow‐up days), days of antibiotic therapy to treat UTI (215 vs 132/1000 patient follow‐up days), and hospitalization due to UTI (2.64 vs 1.07/1000 patient follow‐up days) decreased while patients took methenamine. Escherichia coli and Klebsiella pneumoniae were the most commonly identified cause of UTI both pre‐ and post‐intervention. Drug resistant bacteria (ESBL‐producing or VRE) affected 3 patients pre‐ and recurred in 1 of those patients plus 3 new patients post‐methenamine. Methenamine had few adverse side effects for patients. One patient had nausea and 1 was intolerant. Conclusion We found that methenamine is well tolerated and is useful in reducing UTI, antibiotic prescriptions, and hospitalization in RTR with recurrent UTI. Larger prospective studies are needed to confirm these findings.

Microtubules are hollow protein filaments consisting of the alpha/beta-tubulin subunit, and they play important roles in various biological processes such as cell division, intracellular transport, cell motility and cell morphogenesis. The dynamics of microtubules is critical to the proper function of microtubules in cell division. One of the challenges in improving our understanding of microtubule dynamics is the small size of tubulin subunits. Because each subunit is only few nanometers in size and significantly smaller than the wavelength of light, optical microscopy cannot be used to resolve the interactions of the subunits, which lead to the formation of microtubules, in real time. We developed an in vitro spectroscopy assay for detecting microtubule formation below the diffraction limit of light. The assay is based on Förster resonance energy transfer between fluorescent molecules of a single type (homoFRET). Our results indicate that homoFRET can be used to detect short microtubules even when they are diffraction limited (smaller than few hundred nanometers). We also demonstrate that when fluorophores with appropriate Förster distance are used, this technique can be highly sensitive to the formation of microtubules but less sensitive to the extent of microtubule elongation, making it suitable for detecting microtubule nucleation.