WCN26-436 De novo idiopathic nodular glomerulosclerosis in a kidney transplant patient

Introduction: Immunoglobulin A nephropathy (IgAN) is a common cause of glomerulonephritis that can progress to end-stage renal disease (ESRD).IgA vasculitis, a systemic small vessel vasculitis, is a recognized secondary cause of IgAN.Although rare, rapidly progressive glomerulonephritis (RPGN) can occur in the context of IgA vasculitis, with drug-induced immune responses implicated in some cases.Methods: A 74-year-old Filipino female with no known comorbidities initially presented with flu-like symptoms two weeks prior to admission.She later developed hypogastric pain and dysuria, for which she was treated with cefuroxime 500 mg tablet twice daily for two days for urinary tract infection (UTI).Despite treatment, her symptoms worsened, progressing to generalized abdominal pain and vomiting, prompting admission.She was treated with ceftriaxone 2 g intravenously daily and was referred to nephrology for elevated creatinine (2.4 mg/dL, eGFR 21 mL/min/1.73m2).Two days later, she developed non-blanching, non-palpable, non-pruritic, painless petechial and macular lesions on her lower extremities, accompanied with arthralgia and altered sensorium.Laboratory results revealed progressive renal dysfunction (creatinine 5.15 mg/dL, eGFR 8 mL/min/1.73m2), proteinuria, hematuria, and oliguria, suggestive of RPGN.Renal biopsy was indicated but was deferred due to financial constraints.Ceftriaxone was discontinued, renal replacement therapy was initiated, and pulse methylprednisolone therapy followed by oral prednisone was given.A skin punch biopsy with direct immunofluorescence was done instead which confirmed IgA vasculitis.Results: This case illustrates an exceptionally rare presentation of RPGN secondary to IgA vasculitis in an elderly patient, with atypical non-palpable skin lesions rather than the characteristic palpable purpura.The temporal association with cephalosporin use raises the possibility of a drug-induced immune response, complicating the diagnostic process.Despite timely intervention, the patient remains hemodialysis-dependent to date.Conclusion: Although rare, IgA vasculitis can progress to severe lifealtering RPGN.In this case where renal biopsy was not feasible, a skin biopsy provided critical diagnostic insight.While not a substitute for renal biopsy, skin biopsy may be a valuable tool in selected vasculitis cases especially in resource-limited settings.Early intervention is critical to prevent irreversible renal damage and to improve long-term outcomes.