A case of protein-losing enteropathy in idiopathic thrombocytopenic purpura with decreased IgA.

A young woman presented with high fever and edema in January, 1984, and was diagnosed as having systemic lupus erythematosus. Prednisolone administration failed to improve her symptoms. In May she was admitted to hospital because of elevated erythrocyte sedimentation rate (ESR), hypoproteinemia, hypogammaglobulinemia, hypocomplementemia, positive antinuclear antibody, elevated immune complex level, and diarrhea. Edema disappeared following administration of diuretics and albumin, although the pathogenesis was still undetermined. In September, she was referred to our institution because of severe watery diarrhea and hypoproteinemia. Endoscopic examination showed a diffuse inflammatory lesion in the duodenum and the colon. Radioisotopic 51Cr-albumin study results were compatible with protein-losing enteropathy. Hypoproteinemia and inflammatory changes of the intestine were improved by antibiotics, suggesting that the inflammatory lesion was caused by bacterial infection. Despite the improvements in clinical symptoms and laboratory findings, the serum IgA level was still low and the thrombocytopenia remained. The morphological characteristics of the megakaryocytes were consistent with idiopathic thrombocytopenic purpura. In May, 1986, the thrombocytopenia deteriorated, causing purpura. Prednisolone was administered again, and this resulted in normalization of the platelet count, although the IgA level remained low. Finally the prednisolone was stopped, and the IgA level gradually recovered, with the improvement of the enterocolitis. The exact pathogenesis of the whole picture in this case is unclear, but an 8-year-long clinical course suggests that the protein-losing was caused by an infectious enterocolitis superimposed on IgA deficiency.