Stages in LAV/HTLV-III lymphadenitis. I. Histological and immunohistological classification.

Lymph nodes from 40 homosexuals with persistent, generalized lymphadenopathy were studied for histological and immunohistological changes and classified into histological stages based on the progressive destruction of lymph node follicles in association with progression of the disease. Three patterns were recognized: stage I was characterized by follicular hyperplasia, mantle zone depletion, and follicular fragmentation in the absence of vasculitis, stage II by signs of follicular involution, and stage III by depletion of follicles and dendritic reticulum cells with development of diffuse pattern. The T zone was gradually depleted of CD4-positive lymphocytes, but on further progression, lymphocytic depletion (which also involved the CD8-positive cells) and fibrosis prevailed. The 40 lymph nodes from homosexuals were classified as stage I in 18 cases, stage II in 11, and stage III in 10. One case did not fulfil our histological criteria for LAV/HTLV-III lymphadenitis, although this patient was seropositive. Convincing correlation was found between histological stages and clinical and laboratory data. The triad of follicular hyperplasia, mantle zone depletion, and follicular fragmentation, in the absence of vasculitis, appears pathognomonic for the early disease. The diffuse pattern, however, may be seen in different disease entities.