Immunohistochemical analysis of lymphocytes in postmortem study of the heart from fatal cases of the eosinophilia myalgia syndrome and of the toxic oil syndrome

Abstract

Inflammatory lesions of coronary arteries and cardiac neural structures are postmortem histopathologic features of both the eosinophilia-myalgia syndrome (EMS) and the toxic oil syndrome (TOS). The inflammation is primarily lymphocytic. For further definition of the lymphocytes, immunohistochemical analysis was carried out in the hearts of three victims of EMS and four victims of TOS. Many CD45RO+ T cells, OPD4+ helper/inducer T (Th) cells, and CD20+ B cells were observed in these neurovascular lesions, notably in the conduction system and the coronary chemoreceptor. T cells were prominent in EMS around nerves, ganglia, and sometimes around arteries. B cells and Th cells, however, were more prominent in TOS around arteries. The percentage of T cells in EMS (59.6 ± 2.4%) was significantly higher than in TOS (45.0 ± 4.2%), whereas that of B cells was significantly higher in TOS (27.7 ± 4.4%) than in EMS (17.5 ± 1.3%) ( p < 0.01, respectively). There was no significant difference between the syndromes in the percentages of Th cells. Therefore cytotoxic/suppressor T cells are more prominent in EMS than in TOS. These findings suggest that (1) cellular immune mechanisms are involved in cardioneuropathy in victims of both EMS and TOS; (2) cell-mediated cytotoxicity directed against chemoreceptor neural structures and sinus nodal myocytes is prominent in EMS; and (3) some humoral factors may also be involved in the pathogenesis of TOS.