Abstract
BACKGROUND: Hemodialysis is an important life-sustaining treatment for patients with end-stage renal failure (ESRF), but its ultrafiltration process may induce hypoalbuminemia and compromise systemic immune competence. In Ulcerative colitis (UC), immune dysregulation underlies chronic inflammation. Vedolizumab (VDZ), a humanized monoclonal antibody selectively targeting the α4β7 integrin expressed on gut-homing lymphocytes, demonstrates efficacy in moderate-to-severe UC. However, its pharmacokinetic profile in hemodialysis-dependent patients remains poorly defined due to limited data in this population. CASE PRESENTATION: A 50-year-old male with ESRF secondary to renal allograft failure (2012) received maintenance thrice-weekly hemodialysis. In February 2022, he developed mucoid and bloody purulent stools and was diagnosed with UC. Initial therapy with oral mesalazine (4 g daily) failed to control symptoms, resulting in clinical deterioration. Subsequently, VDZ was initiated at a standard induction regimen: 300 mg intravenous infusions at weeks 0, 2, 6, followed by maintenance dosing every 8 weeks. INTERVENTION AND OUTCOME: Clinical remission with complete mucosal healing (Mayo endoscopic score 0) was achieved by week 22. Post-dialysis trough serum VDZ concentration measured 13.35 μg/mL, with no detectable anti-drug antibodies. Renal function remained stable throughout (estimated glomerular filtration rate [eGFR] 3.45 mL/min/1.73m(2)), confirming therapeutic efficacy without exacerbation of uraemic complications.