Abstract
Objective: To report a case of C1q nephropathy associated with viral infection and refractory to immunosuppressive therapy, in addition to describing the characteristics of this disease that differentiate it from lupus nephritis. Case details: Young patient with nephrotic syndrome and diagnosis of C1q nephropathy established by renal biopsy, without classification criteria for systemic lupus erythematosus, without adequate response to cyclophosphamide and mycophenolate, presenting diagnosis of cytomegalovirus infection throughout evolution, also without improvement of renal condition after antiviral therapy, having evolved with COVID19 and unfavorable outcome. Final considerations: C1q nephropathy is a relatively new histopathological entity of glomerulonephritis, with reports and series of cases more frequently described. It presents several clinical manifestations, and the diagnosis is defined by the findings of immunofluorescence and electron microscopy of renal biopsy. Corticosteroids are the basis of treatment, but many patients have resistance or dependence to corticosteroid therapy. Prognosis is variable and depends on clinical-pathological presentation.