SPECTRUM OF MORPHOLOGIC CHANGES OF LYMPH-NODES IN HIV-INFECTION

Cervical lymph nodes biopsies from 31 HIV positive patients (with or w ithout AIDS) were studied by histologic methods and immunohistochemist ry (StreptABC staining of paraffin sections) to identify cellular and extracellular matrix components. The results were the following: (1) t he biopsies were included in the stages of follicular hyperplasia with out fragmentation FH-FF (4 cases); follicular hyperplasia with follicu lar fragmentation FH+FF (16 cases); follicular involution FI (6 cases) and diffuse pattern DP (5 cases); (2) the most important alteration w as the germinal centers disruption due to follicle lysis, which began in the light zone; (3) there was coincidence between intrafollicular h emorrhages and segmental hyaline mycroangiopathy; (4) during the progr ession of the disease occurred: (a) an increase in the number of mast cells, CD68(+) and Mac387(+) macrophages; (b) a diffuse augment of col lagen III, elastic fibers, laminin, fibronectin and proteoglycans; (c) maintenance of Factor VIII - related antigens in the vascular endothe lial cells, with decrease in the expression of Ulex-Europeus I lectin. Follicular hyperplasia (FH-FF or FH+FF) was the most common histologi c pattern recognized in the lymph nodes of patients without AIDS and f ollicular involution and difuse pattern were seen in those who had AID S. The results indicate that the lymph node biopsies may provide impor tant information about the evolutive stage of the disease and its prog nosis.