Re-Occurring Proteinuria in a SLE Patient: Always Lupus Nephritis?

Introduction: Renal disease, designated as lupus nephritis (LN), is one of the severe manifestations of Systemic Lupus Erythematosus (SLE). The proliferative forms require aggressive treatment with corticosteroids and cytotoxic drugs. In a substantial number of patients, renal disease relapses after treatment. Case report: In this case report, we present a 27-year old woman, who had been treated for a membranoproliferative LN in the past. Seventeen years later she presented with chest pain and nephrotic-range proteinuria and severe hypoalbuminemia. The diagnosis of pulmonary embolism was made. Renal biopsy revealed only minimal abnormalities, confined to the mesangium. There was no glomerulonephritis. Based on this finding and the nephrotic-range proteinuria, the diagnosis of minimal-change disease was made. The patient was treated with prednisolone, after which the proteinuria diminished, but did not disappear. After the addition of azathioprine, the proteinuria resolved completely. Conclusion: This case illustrates that, although the diagnosis of LN has been made in the past, this does not exclude the occurrence of renal pathology caused by other diseases than SLE. Therefore, a renal biopsy is mandatory in every SLE patient with occurrence of renal abnormality es, even when a history of LN is present.