Immunosuppressive strategies for renal function preservation in IgA nephropathy with partial crescent formation: A retrospective cohort study

OBJECTIVE: The aim of this study is to assess renal outcomes and long-term prognosis associated with different therapeutic regimens, including supportive care and immunosuppressive therapy, in patients with IgA nephropathy (IgAN) presenting with partial crescent formation. The objective is to provide evidence-based recommendations for the management of early-stage crescentic IgAN. MATERIALS AND METHODS: A single-center retrospective cohort study was conducted, involving 134 adults diagnosed with biopsy-proven IgAN and partial crescents. Participants were categorized into three groups: the renin-angiotensin system inhibitors (RASI) group, the prednisone (P) group, and the P plus cyclophosphamide (CTX) group. Data were extracted from hospitalization records and outpatient follow-ups over a 2-year period. The primary outcomes measured were the decline in estimated glomerular filtration rate (eGFR) and reduction in proteinuria. RESULTS: Patients in the P+CTX group had comparatively worse baseline clinical parameters than the other two groups - for example, higher proteinuria, lower serum albumin, and poorer renal function. Nevertheless, following 6 months of immunosuppressive therapy, 60.00% of patients in the P+CTX group achieved effective remission. Urinary protein levels in this group decreased from 1,534.00 mg/day at baseline to 289.50 mg/day at the 24-month follow-up. Renal function remained stable within the P+CTX group throughout the follow-up period. Although the effective remission rate was comparable among all groups after the sixth month, no significant differences were observed in the incidence of endpoint events across the three groups. Thus, the P+CTX group presented significant improvements in proteinuria. CONCLUSION: Despite more severe baseline disease, the P+CTX regimen was associated with a greater reduction in proteinuria in IgAN patients with minor crescent formation. It is important to note, however, that causal inference was limited by residual confounding. Despite adequate short-term safety, extended follow-up is mandatory to fully evaluate the long-term complications of CTX.