Renal thrombotic microangiopathy is associated with poor renal survival in children with immunoglobulin A nephropathy

Nephrology (Carlton). 2024 May 8. doi: 10.1111/nep.14313. Online ahead of print.

Abstract

Aim: The aim of this study was to examine the clinical and pathological characteristics as well as the prognosis of immunoglobulin A nephropathy (IgAN) accompanied by renal thrombotic microangiopathy (rTMA) in paediatric patients.

Methods: After balancing epidemiological characteristics and pathological types between groups, 427 patients (rTMA group: 23, non-rTMA group: 46) were included. The clinical and pathological features, prognosis and clinical risk factors of the two groups were analysed.

Results: IgAN-rTMA children showed more severe clinical and pathological manifestations. The findings from the logistic regression analysis indicated that hypercellularity 1 (E1) (HR: 0.805, 95% CI: 0.763 ~ 1.452, P = .016), endocapillary proliferation (HR: 1.214, 95% CI: 0.093 ~ 4.815, P = .025) and C3 staining (HR: 7.554, 95% CI: 2.563 ~ 15.729, P = .037) were the risk factors for rTMA in children with IgAN. The renal survival in rTMA group was lower than non-rTMA group (χ2 = 18.467, P = .000). Cox regression analysis showed that E1 (HR: 7.441, 95% CI: 1.095 ~ 10.768, P = .037), C3 disposition (HR: 3.414, 95% CI: 0.834 ~ 11.578, P = .027) and rTMA (HR: 8.918, 95% CI: 1.032 ~ 16.754, P = .041) were identified as independent risk factors for the development of end-stage renal disease (ESRD).

Conclusion: The presence of rTMA had a significant impact on the severity and prognosis of IgAN. And rTMA has been identified as an independent risk factor for the development of renal failure in children diagnosed with IgAN.

Keywords: children; immunoglobulin A nephropathy; pathology; prognosis; renal thrombotic microangiopathy.