Clinical Profile and Outcomes of Thrombotic Microangiopathy: A Kidney Biopsy Registry Cohort

Background Thrombotic microangiopathy (TMA) is caused by injury to microvasculature that leads to thrombus formation and multisystem dysfunction. TMA can cause irreversible kidney failure and graft failure in kidney transplant patients. The data on etiology, clinical and histopathological characteristics, treatment patterns, and renal outcomes of patients with TMA from resource-limited health care setups is less. Materials and Methods From a South Indian teritiary care center biopsy registry of 16,054 patients, 87 TMA cases diagnosed between January 2011 and April 2022 were included, and follow-up data were collected from electronic medical records until June 2023. Results The mean age of the cohort was 31.7± 9.9 years. The biopsy incidence of TMA was 0.5% during the study period. The most common TMA etiology was autoimmune disease (25.2%), followed by atypical HUS (18.4%) and pregnancy-associated and malignant hypertension (14.9%) each. The most common renal biopsy finding was mesangiolysis (74.7%), followed by capillary wall thrombi and fragmented RBCS. On a median 6-month follow-up (1,36), 24 (27.6%) patients showed renal recovery, and 40 (46%) remained dialysis-dependent. Multivariate analysis showed that dialysis dependence at presentation adversely affected renal recovery. Conclusion TMA, although rare, carries a high risk of renal failure and death. With early diagnosis and treatment, satisfactory renal outcomes can be achieved even in resource-limited health care settings.