Chagas' disease encephalitis: Intense CD8(+) lymphocytic infiltrate is restricted to the acute phase, but is not related to the presence of Trypanosoma cruzi antigens

Central nervous system (CNS) damage can occur during Chagas' disease, espec ially in children and immunosuppressed patients. During the acute phase, am nastigotes are rarely found, but inflammatory infiltrates are scattered thr oughout the CNS, Moreover, peripheral lymphocytes and antibodies recognizin g neural components were described, suggesting the participation of the imm une system in the genesis of neural lesions. Herein, we performed a histopa thological study of Colombian-infected C3H/He mice, comparing the distribut ion of CNS-inflammatory infiltrates versus Trypanosoma cruzi antigens. Infl ammatory infiltrates were observed during the acute phase, but did not corr elate with the presence of detectable T. cruzi antigens. Infiltrates consis ted mainly of CD8(+) lymphocytes, although macrophages and a few CD4(+) cel ls were observed. In the chronic stage of infection, although neuropathies were a common finding, only mild inflammatory infiltrates could be detected . Our results suggest that the presence of CNS inflammatory infiltrates is not directly related to the presence of parasite antigens and indicate that , different from chronic myocarditis, encephalitis resolves during the acut e phase of Chagas' disease. (C) 1999 Academic Press.