Blood vessels in human immunodeficiency virus-related lymphoadenopathy: high endothelial venules and lymphocyte...

The vasculature of 25 lymph nodes of patients with human immunodeficiency virus-related lymphadenopathy was investigated morphometrically. The number of small vessels, the morphological features of high endothelial venules and the migratory index of the lymphocytes passing through the high endothelial venules, as well as the stage-dependent change of each parameter, were analysed. Twenty reactive lymph nodes served as controls. The total number of vessels in the HIV-infected lymph nodes was relatively stable. However, the small vessels with flat endothelium increased in number, while the number of high endothelial venules decreased as the disorder progressed, and the decrease in the lymphocyte migration seemed to precede the change in the morphology of high endothelial venules. The presumptive role of these alterations in the pathogenesis of the investigated disorder is emphasized.