Seronegative systemic lupus erythematosus: etiology of nephrotic syndrome and acute renal failure in early postpartum period.

Systemic lupus erythematosus (SLE) is an autoimmune syndrome that occurs most commonly in women during their reproductive years. Nephritis is known to be one of the most serious complications of SLE. Lupus nephropathy is frequently associated with ANA and anti-dsDNA antibodies. Rarely, serological markers may be initially absent, and in many cases, they become positive after sometime. We present a 28-year old, otherwise healthy female who admitted to our clinic with edema, hypertension, proteinuria and acute renal failure following her fourth delivery. Serum immunological markers were negative and renal biopsy showed histopathological changes consistent with systemic lupus erythematosus as the etiology of nephrotic syndrome. A dramatic therapeutic response was achieved by pulse steroid and cyclophosphamide treatment following oral steroid therapy. In women with new onset nephrotic syndrome or renal function deterioration in postpartum period, even if the patient is asymptomatic or seronegative, it is crucial to exclude SLE for a rapid diagnosis and prompt treatment in the case of lupus nephritis. Renal biopsy is of diagnostic importance in such cases in which there is no other clinical, biochemical and serological evidence of the disease.