Amongst the various causes of anemia in systemic lupus erythematosus, isolated and acquired erythrocyte dysplasia is rare and most often part of global dysmyelopoiesis. The authors report a case of acquired erythrocyte dysplastic syndrome that occurred in a 34-year-old woman in whom previous diagnosis had evidenced systemic lupus erythematosus of rather benign course. Other causes of dysmyelopoiesis were ruled out. Myeloid stem cell cultures showed selective inhibition of erythroid cells growing, with no particular effect of the patient's serum. While a corticosteroid treatment with prednisone (1 mg/kg/d) did not show any efficacy upon anemia, the patient's pregnancy was followed by prolonged correction of hemoglobin, making possible the tapering of prednisone down to 10 mg/d. Acquired erythrocyte dysplastic syndrome remains a rare cause of anemia in systemic lupus erythematosus. This case report suggests an immunological phenomenon, but the mechanisms underlying both the appearance and long-lasting remission after pregnancy remain unexplained.