Nephrotic syndrome in the course of type 1 diabetes mellitus and systemic lupus erythematosus with secondary antiphospholipid syndrome – diagnostic and therapeutic problems

Nephrotic syndrome (NS) can be a symptom of many autoimmune, metabolic, or infectious diseases. Kidney involvement is often observed in the course of diabetes mellitus (DM) and systemic lupus erythematosus (SLE). The development of NS with coexisting SLE and DM generates serious diagnostic problems. In this paper, the authors present diagnostic and therapeutic dilemmas in a patient with long-lasting DM, SLE, and secondary antiphospholipid syndrome, in whom NS symptoms appeared. Histopathological examination of the kidney confirmed the diagnosis of lupus nephritis. Immunosuppressive and anticoagulant drugs were used. The authors demonstrated that the character of morphologic lesions in the kidney biopsy can help in diagnosis, nephropathy classification, and further therapeutic decisions, which are distinct in both diseases.