BACKGROUND. Control of the tuberculosis (TB) pandemic remains hindered in part by a lack of simple and accurate measures of treatment efficacy, as current gold standard markers rely on sputum-based assays that are slow and challenging to implement. However, previous work identified urinary N 1 , N 12-diacetylspermine (DiAcSpm), neopterin, hydroxykynurenine, Nacetylhexosamine, ureidopropionic acid, sialic acid, and mass-to-charge ratio (m/z) 241.0903 as potential biomarkers of active pulmonary TB (ATB). Here, we evaluated their ability to serve as biomarkers of TB treatment response and mycobacterial load. METHODS. We analyzed urine samples prospectively collected from 2 cohorts with ATB. A total of 34 study participants from African countries treated with first-line TB therapy rifampin, isoniazid, pyrazinamide, and ethambutol (HRZE) were followed for 1 year, and 35 participants from Haiti treated with either HRZE or an experimental drug were followed for 14 days. Blinded samples were analyzed by untargeted HPLC-coupled high-resolution TOF-mass spectrometry. RESULTS. Urinary levels of all 7 molecules significantly decreased by week 26 of successful treatment (P = 0.01 to P < 0.0001) and positively correlated with sputum mycobacterial load (P < 0.0001). Urinary DiAcSpm levels decreased significantly in participants treated with HRZE as early as 14 days (P < 0.0001) but remained unchanged in cases of ineffective therapy (P = 0.14). CONCLUSION. Urinary DiAcSpm, neopterin, hydroxykynurenine, N-acetylhexosamine, ureidopropionic acid, sialic acid, and m/z 241.0903 reductions correlated with successful anti-TB treatment and sputum mycobacterial load. Urinary DiAcSpm levels exhibited reductions capable of differentiating treatment success from failure as early as 2 weeks after the initiation of chemotherapy, advocating its further development as a potentially simple, noninvasive biomarker for assessing treatment response and bacterial load.

BackgroundAdequate control of the global tuberculosis (TB) burden is limited by a lack of accurate measures of treatment efficacy. Current gold standard relies on sputum cultures, which often lag weeks behind time of sample collection. Previous studies have identified urinary N1,N12-diacetylspermine (DiAcSpm) as a potential biomarker of active pulmonary TB (ATB). We aimed to quantify urinary DiAcSpm in participants being treated for ATB and identify its relationship to treatment response.MethodsLongitudinal urine samples were obtained from two separate cohorts of participants treated for ATB. Cohort one consisted of 34 successfully treated ATB cases with urine collected at weeks 0, 2, 4, 8, 17, 26, and 52. Cohort two consisted of 35 ATB cases under two treatment arms: one arm was successfully treated with the standard therapy of rifampin, isoniazid, pyrazinamide, and ethambutol (RIPE), and the other arm received an experimental drug, which was later found to be ineffective against ATB. Urine from cohort two was collected at days 0, 2, 4, and 14. All samples were blinded, randomized, normalized to osmolality and urinary creatinine, and analyzed using high-performance liquid chromatography-mass spectrometry. DiAcSpm concentrations were further tested using ELISA.ResultsUsing linear-mixed modeling that adjusted for age, sex, and participant weight, we found that urinary DiAcSpm significantly decreased by week 2 of successful treatment in both cohorts (P < 0.0001). DiAcSpm levels remained unchanged in the ineffective experimental drug group (cohort two), significantly differentiating treatment success and failure by day 14 (P < 0.0001). Additionally, concentrations of urinary DiAcSpm positively correlate with sputum mycobacterial burden (P = 0.0002).These findings were consistent across both methods of detection.ConclusionOur results suggest that urinary concentrations of DiAcSpm correlate with TB treatment outcome and mycobacterial disease burden, and have the potential to serve as an early biomarker of TB treatment efficacy. Disclosures All Authors: No reported Disclosures.