External validation of the international IgA nephropathy prediction tool in a Thai cohort

The study validated the performance of the International IgA Nephropathy Prediction Tool (IIgANPT) in 133 Thai patients with biopsy-proven IgA nephropathy. During a median follow-up of 3.4 years, 45 patients (33.8%) reached the renal endpoint, defined as a sustained 50% decline in glomerular filtration rate or progression to end-stage renal disease. The tool demonstrated good discrimination with C-statistics of 0.753 to 0.754 and five-year AUC values of 0.790 to 0.787. Calibration was broadly preserved and risk groups showed clear separation. Both model versions (with and without race) performed similarly, suggesting that excluding the race variable had limited impact on prognostic performance in this relatively homogeneous population.