[Abstract]ObjectiveTo report the first case of Churg-Strauss syndrome (CSS) manifested as IgA nephropathy in China. MethodsThe clinicopathological data for diagnosis of the patient were analyzed, and the related literatures were reviewed. MethodsThe female patient aged 39 years old. Renal needle biopsy was performed 6 years ago because of gross hematuria and proteinuria, with the diagnosis being IgA nephropathy and focal segmental glomerulosclerosis. Laboratory examinations showed that the proportion of peripheral eosinophils was increased and c-ANCA/p-ANCA was positive once. Sufficient prednisone and cyclophosphamide were given for pulse therapy for 18 months, and the patient was clinically cured. One year ago, the patient received peritoneal dialysis because the serum creatinine reached 932 μmol/L. However, the general status of the patient was not improved after dialysis, and the patients developed cough, diarrhea and low-grade fever. Repeated blood test showed that the proportion of peripheral eosinophils was continuously increased. p-ANCA and MPO-ANCA were positive, and CT scan indicated chronic sinusitis. The patient had a history of “rashes”, therefore CSS was diagnosed. The patient was given pulse therapy with immunoglobulin treatment for 3 days and oral prednisone at a daily dose of 30 mg; the temperature of the patient decreased immediately to the normal level; and her general condition was improved and she was discharged. Methods IgA nephropathy was a rare pathological manifestation of CSS, which should be considered during diagnosis.