HISTOPATHOLOGIC FINDINGS IN THE LYMPHOID AND RETICULOENDOTHELIAL SYSTEM IN PEDIATRIC HIV-INFECTION - A POSTMORTEM STUDY

The present report describes the histopathological features of lymphor eticular tissues in 29 pediatric autopsies of human immunodeficiency v irus (HIV)-infected patients. Mean age for the whole group was 1.77 ye ars; 68.9% and 62% of the cases were 2 years old or less and 1 year ol d or less at the time of death, respectively. Twenty-one cases were ca tegorized as acquired immunodeficiency syndrome (AIDS) and the rest in cluded seven HIV-positive newborns and infants and two infants belongi ng to a high-risk group. The thymus (24 cases) showed severy lymphoid depletion (atrophy) in 16 (66.6%) cases, microcystic transformation of Hasall's corpuscles (HCs) in 4, calcified HCs in 3, absence of HCs in 3, and plasmacytic infiltrates and Warthin-Finkeldey-type multinuclea ted giant cells (also found in lymph nodes and bowel lymphoid aggregat es in the same case) in 1. Lymph nodes (25 cases) revealed extensive l ymphocyte depletion (68%); selective follicular (2 cases) or paracorti cal (3 cases) atrophy; hemophagocytosis (44%); some type of hyperplasi a (plasmacytosis, enlarged follicles) in 5 cases; some type of lymphad enitis (12 cases), 5 cases of which were due to opportunistic infectio ns (cytomegalovirus, 2; histoplasmosis, cryptococcosis, Mycobacterium avium-intracellulare, 1 each). Main findings in the spleen (28 cases) were extensive lymphocyte depletion (10 cases), limited to the white p ulp in 4 and including the red pulp in 7; some type of lymphoid hyperp lasia (limited to white pulp in 6 cases and involving the red pulp in 5); hemophagocytosis (7 cases); and foci exhibiting a peculiar arrange ment of spindle-shaped cells combined with capillaries, plasma cells, and occasionally siderophages in 11. These we have termed kaposiform a reas due to the resemblance to the so-called inflammatory variant of K aposi's sarcoma. This pattern was also recognized in lymph nodes of tw o cases. Although atrophy was the main theme, cases with hyperplasia w ere also noticed. The possible relationship, if it exists at all, betw een kaposiform areas and Kaposi's sarcoma remains to be established. N o tumor was found in this series. No specific histopathologic pattern of lymphoid tissues atributable to HIV emerged form this study aside f rom kaposiform areas, a microscopic feature not previously reported in this circumstance in pediatrics.