Supplementary Material for: Histopathologic Features that Predict Transplant Glomerulopathy Progression in a Chinese Cohort

Background: Transplant glomerulopathy (TG) represents a major cause of long-term allograft failure and is the leading cause of overall post-transplant proteinuria. The extent to which histopathologic features predicts prognostication is uncertain. Methods: A single-center retrospective cohort with biopsy-proven TG was investigated. Renal biopsies were scored according to Banff 2017. The primary outcome was death-censored graft failure defined as return to dialysis or estimated glomerular filtration rate (eGFR) decreased to 2. The prognostic significance of clinical and histopathologic parameters was determined using Cox proportional hazards models. Results: Data from 180 cases were available for analysis with a median follow-up of 5.0 (2.6–8.2) years. In multivariable models, ci + ct score (HR 3.1; 95% CI 2.0–4.9), cg score (HR 1.7; 95% CI 1.1–2.8), eGFR (HR 2.1; 95% CI 1.4–3.2) and proteinuria (HR 2.4; 95% CI 1.6–3.7) were independent predictors of the primary outcome. Mesangial Immunoglobulin A deposition did not significantly affect allograft survival. The only significant pathologic factors for the severity of proteinuria were cg and g + ptc (adjusted R2 = 0.46) as determined by multivariable stepwise linear regression analysis. Conclusions: Severe ci + ct and cg at biopsy were predictors of unfavorable allograft prognosis in TG patients even after taking into consideration clinical characteristics. Histologic severity of cg and g + ptc was significantly associated with clinical proteinuria.