Trimethoprim-Sulfamethoxazole (TMP/SMX) Prophylaxis After Acute Kidney Injury to Prevent Post-discharge Infections

Official Title Trimethoprim-Sulfamethoxazole (TMP/SMX) Prophylaxis After Acute Kidney Injury to Prevent Post-discharge Infections: A Randomized, Double-Blind, Placebo-Controlled Trial Brief Summary Acute kidney injury (AKI) is commonly followed by infections after hospital discharge. This randomized, double-blind, placebo-controlled trial will test whether prophylactic TMP/SMX reduces post-discharge infections in adults recently hospitalized with AKI. Participants will be randomized 1:1 to TMP/SMX or matching placebo and followed for 6 months. The primary outcome is the proportion of participants who develop any infection within 90 days after discharge. Secondary outcomes include time to first infection, infection-related hospitalization, mortality, safety/adverse events, and healthcare utilization through 180 days. Detailed Description Adults discharged after an index hospitalization complicated by AKI are at elevated infection risk. This trial evaluates whether short-term TMP/SMX prophylaxis reduces 90-day infections. After consent and eligibility confirmation near discharge, participants are randomized (1:1) to receive TMP/SMX or matching placebo with double-blind masking (participant and outcome assessor). Dosing is standardized per protocol. We will ascertain infections via structured follow-up, medical record review, and adjudication by blinded assessors. Safety monitoring will capture adverse events (e.g., rash, cytopenias, hyperkalemia). Analyses follow intention-to-treat. Study Design * Study Type: Interventional (Clinical Trial) * Primary Purpose: Prevention * Allocation: Randomized (1:1) * Intervention Model: Parallel Assignment * Masking: Double-blind (Participant, Outcomes Assessor) * Estimated Enrollment: 60 patients per group * Study Start Date: December 2025 * Primary Completion Date (Anticipated): January 2027 (last patient reaches 90-day outcome) * Study Completion Date (Anticipated): July 2028 (last patient completes 180-day follow-up) Arm