[Angioimmunoblastic lymphadenopathy. Diagnosis and differential diagnosis].

On the basis of 8 biopsy and 3 autopsy cases of the Pathological Department, Schwerin County Hospital and of 4 selected biopsy and autopsy cases of the Department of Pathology, Medical University of Pécs, the pathomorphological diagnosis and differential diagnosis of angioimmunoblastic lymphadenopathy (AIBLP) or lymphogranulomatosis X are discussed. Borderline lesions between common reactive changes and AIBLP are high-grade paracortical hyperplasia and the so-called angioimmunoblastic reaction (AIBR) which may be associated with a partial transformation of lymph node structure. On the other hand, AIBLP should be differentiated from malignant lymphomas (immunoblastoma, T-zone lymphoma, Hodgkin's disease). The polyclonality of plasma cells, the presence of mature lymphocytes in higher numbers, the low mitotic rate, the absence of atypical giant cells all speak for AIBLP. AIBLP can be subdivided into several types (immunoblast-rich, plasma cell-rich, mixed cell type, epitheloid cell-rich type and lymphocyte-rich type. Lennert et al. 1979), the prognostic relevance of which should be assessed on a large number of cases.