Interstitial pneumonia in angio-immunoblastic lymphadenopathy with dysproteinemia. A case report with special histopathologic studies.

A patient presented with characteristic historical, physical, and laboratory findings of angio-immunoblastic lymphadenopathy with dysproteinemia. This newly described entity apparently represents a nonneoplastic proliferation of the B-lymphocyte system with immunoblastic transformation of many lymphocytes and excessive production of immunoglobulins. It is associated with fever, sweats, weight loss, skin rash, lymphadenopathy, splenomegaly, hepatomegaly, and characteristic histologic features of the involved lymph nodes. Noteworthy in the patient reported here are the extent and course of radiographically and clinically evident pulmonary involvement and the biopsy documentation of an interstitial pneumonia marked by histopathologic changes closely resembling those found in the lymph nodes, with immunohistologic demonstration of immunoglobulins in the alveolar walls.