Abstract
BACKGROUND: There is currently little research on the association between immune traits and urethral stricture, and the diversity of immune cell subtypes leads to an unclear association with urethral stricture. This study investigated the relationship between immune cells and urethral stricture using the Mendelian randomization (MR) technique. METHODS: We assessed the causative relationships between urethral stricture (N = 341,285) and 731 immunological characteristics (N = 3757). The main technique was the inverse-variance weighted (IVW) approach, which was supplemented by MR-Egger and weighted median (WM). The robustness of MR results was assessed using sensitivity analyses, primarily the Egger intercept, Cochran's Q test, MR-PRESSO, and leave-one-out test. RESULTS: Our findings revealed that 37 immune phenotypes have suggestive causal relationships with urethral stricture, including 13 subtypes of B cells, four classical dendritic cells, three myeloid cells, five monocytes, four TBNK, five Treg cells, and three maturation stages of T cells. Sensitivity analyses revealed neither heterogeneity nor pleiotropy. CONCLUSIONS: Our findings supported a potential causal relationship between immune cells and urethral stricture. This may guide the management and treatment of urethral stricture in the future.