[An uncommon case of lupus].

A 44-year-old patient was referred with weight loss of some 6 kg in two months, weakness and diarrhoea. According to the criteria of the American College of Rheumatology (ACR), systemic lupus erythematosus (SLE) was diagnosed: photodermatosis, nephropathy, and pancytopenia with positive antinuclear antibodies and antibodies against native DNA. In addition, adrenal failure was diagnosed with hyponatraemia, relapsing fever, low baseline cortisol and impaired response to ACTH stimulation. Clinical features of SLE may obscure signs of adrenal insufficiency, and hence, diagnosis is jeopardized. SLE combined with Addition's disease is rare. In some patients with both disorders, antiphospholipid antibodies, as found in our patient, are considered responsible for the development of Addison's disease. Possible pathogenetic mechanisms such as adrenal haemorrhage or (micro)thrombosis are discussed. The patient's condition significantly improved under steroid therapy. The progression of renal insufficiency (histology: mesangioproliferative glomerulonephritis), however, required additional immunosuppression with cyclophosphamide.