At last, through the external validation of our cohort, the upregulated expression patterns of SLPI and MMP9 were confirmed to be consistent with the obtained datasets, and the diagnostic nomogram models based on SLPI and MMP9 levels performed well in significantly differentiating CAVD, particularly CAVD in CKD patients. The gene discussed is MMP9; the disease is congenital bilateral aplasia of vas deferens from CFTR mutation.