RHEUMATIC ASCHOFF NODULES REVISITED - AN IMMUNOHISTOLOGICAL REAPPRAISAL OF THE CELLULAR-COMPONENT

Rheumatic fever is still the leading cause of acquired heart disease i n children and young adults in developing countries. Recent reports ha ve documented a rising incidence of rheumatic fever in both the USA an d Europe. The disease is characterized by specific lesions in the hear t muscle and valves called Aschoff nodules. The Aschoff nodule has bee n neglected in the last few decades as most of the studies were conduc ted in the 1960s on autopsy tissues, This study examines Aschoff nodul es using heart valve material obtained at valve surgery with updated c ommercially available immunohistochemical antibodies to determine the phenotypic characteristics of the cells involved in the formation of t hese lesions, Fifteen cases of rheumatic valvulitis, as indicated by t he presence of Aschoff nodules, were examined, The Anitschkow and Asch off cells stained prominently with macrophage markers. Three stages of nodules with Aschoff and Anitschkow cells were identified: stage 1, c entral fibrinoid necrosis without lymphocytes, stage 2 with occasional T lymphocytes (< 10) and stage 3 with lymphoid aggregates containing both T- and B-lymphocytes (with occasional admired macrophages), We pr opose that the stage 1 lesion is the earliest granulomatous stage with the lymphoid aggregates being a later stage in the development of Asc hoff nodules, The Aschoff and Anitschkow cells demonstrated mitotic ac tivity and stained with antibodies to the proliferation cell nuclear a ntigen (PCNA) suggesting that the multinucleated giant cells may be fo rmed, at least partially, by nuclear division rather than fusion.