Lymphoid changes of the nasopharyngeal and palatine tonsils that are indicative of human immunodeficiency virus infection. A clinicopathologic study of 12 cases.

We report 12 cases in which the histomorphologic changes of the nasopharyngeal tonsils (adenoids) or palatine tonsils suggest infection with the human immunodeficiency virus (HIV). The patients included 10 men and two women, aged 20 to 42 years (median, 33 years). The clinical presentation included airway obstruction, pharyngitis, fever, and a tonsillar or adenoidal mass lesion. Histologic evaluation of the excised adenoids or tonsils in 10 of the cases demonstrated a spectrum of changes including florid follicular hyperplasia, follicle lysis, attenuated mantle zone, and the presence of multinucleated giant cells (MGC). The latter characteristically localized adjacent to the surface or tonsillar crypt epithelium. Two of the 12 cases showed marked lymphoid depletion with absent germinal centers, plasmacytosis, and stromal vascular proliferation. Immunohistochemical evaluation for HIV p24 core protein showed reactivity in 10 of 12 cases localized to follicular dendritic cell network (FDC), the MGC, scattered interfollicular lymphoid cells, and cells identified within the surface or crypt epithelium. Localization of viral RNA by in situ hybridization paralleled the HIV p24 immunohistochemical findings. Additional significant findings included the presence of both CD-68 and S-100 protein in the MGC and the presence of S-100 protein in dendritic cells. Other than HIV, no microorganisms were identified. At the time of presentation, eight patients were not known to be a risk for HIV infection, nor were they known to be HIV infected or suffering from AIDS. In these patients, HIV infection was suspected on the basis of the histologic changes seen in the resected tonsillar and adenoidal tissue. Serologic evaluation (by enzyme-linked immunosorbent assay), confirmed the presence of HIV infection. Our findings suggest the possibility of HIV dissemination through the upper aero-digestive tract mucosa via target cells, such as intraepithelial dendritic cells, submucosal macrophages, and T-lymphocytes. Subsequent presentation of viral antigens to the tonsillar and adenoidal lymphoid tissues results in enlargement of these structures that clinically may simulate a neoplastic proliferation but causes histomorphologic changes that are highly suspicious for HIV infection even in asymptomatic HIV-positive patients.