Hemorrhagic Cystitis in Patients Who Underwent Allogeneic Stem Cell Transplantation (2012-2025): A Single-Center Experience.

INTRODUCTION

Hemorrhagic cystitis (HC) is a common complication of allogeneic hematopoietic stem cell transplantation (HSCT), especially in cases with haploidentical donors. Our study aimed to determine the incidence and analyze the risk factors associated with HC in patients undergoing allogeneic HSCT.

SUBJECTS AND

METHODS

This retrospective, cross-sectional study analyzed data from 343 patients who underwent allogeneic HSCT between January 2012 and June 2025 at our institution. The research variables included clinical characteristics, conditioning regimens, BK virus (BKV) status, and transplant outcomes.

RESULTS

The overall incidence of HC was 18.4% (63 out of 343 patients), with severe cases (Grades 3-4) comprising 9.4%. The median onset was 33 days posttransplantation, with a median duration of 40 days. BKV was detected in the urine of 19.9% of the patients, among whom 15.2% exhibited high viral loads. Multivariate Cox regression analysis identified three independent risk factors: malignant disease (hazard ratio [HR] = 4.212; p = 0.046), posttransplant severe infection (HR = 1.793; p = 0.033), and the use of posttransplant cyclophosphamide (PTcy) (HR = 3.404; p < 0.001). Regarding prognosis, the presence of HC did not significantly affect the 5-year overall survival (OS) probability (67.1% vs. 65.7% in the non-HC group, p = 0.921). However, patients with Grades 3-4 HC exhibited a significantly lower 5-year OS than those with Grades 1-2 (49.6% versus 86.6%, p = 0.007).

CONCLUSION

HC is a prevalent complication of allogeneic HSCT, often presenting late and closely associated with malignancies, severe infections, and PTcy protocols. The severity of HC is a crucial determinant of survival outcomes, necessitating proactive preventive strategies and timely interventions to enhance the patient's prognosis.