Pathology of patients with Chagas' disease and acquired immunodeficiency syndrome.

The main pathologic findings in 23 patients with acquired immunodeficiency syndrome (AIDS) and Chagas' disease are reviewed; five are from our own experience and 18 from the literature. The presence of Trypanosoma cruzi parasites and/or T. cruzi antibodies in blood and cerebrospinal fluid was recorded and computerized tomograms of the brain were evaluated. Twenty (87%) of the 23 subjects developed severe, multifocal or diffuse meningoencephalitis with necrosis and hemorrhage associated with numerous tissue parasites. The second most severely affected site was the heart. Seven (30.4%) of the 23 cases had myocarditis on pathologic examination. It was acute in four patients, chronic in two, and simultaneously acute and chronic in one. Acute myocarditis and meningoencephalitis are interpreted as being caused by relapses of chronic T. cruzi infections. An AIDS permissive role is suggested for these conditions since immunologic defense against T. cruzi is mediated mainly by T lymphocytes, whose CD4 subpopulation is depleted in patients with this disease. Consequently, AIDS is a factor that may favor the reactivation of T. cruzi infections. The lesions reported in the association of Chagas' disease with AIDS were compared with those reported from patients without AIDS having fatal, acute, vector-transmitted infections, contaminated blood transfusions, or accidental exposures in the laboratory. For the latter three, meningoencephalitis is uncommon. Only immunosuppressed cases of Chagas' disease have been described as having a pseudotumoral presentation that shows expanding lesions with a mass effect in the cranial cavity that causes intracranial hypertension and simulates neoplasms (tumors such as gliomas, lymphomas, metastases, etc.).

Estudo caso-controle da infecçäo pelo HIV em pacientes em programa de hemodiálises / Control case study of HIV infection in dialysis patients

O Brasil é o quarto país no mundo em número de casos de AIDS, apresentando elevada proporçäo da doença adquirida através de transfusäo de sangue. Uma vez que os pacientes com insuficiência renal crônica em programa de hemodiálise säo freqüentemente submetidos a transfusöes sanguíneas, constituem-se em grupo com risco potencial de exposiçäo ao HIV. Estudou-se a prevalência de infecçäo pelo HIV em 117 pacientes em programa de hemodiálise na Casa de Saúde Santa Marcelina, identificando-se nove (7,7%) pacientes soropositivos pelos métodos ELISA e Western Blot. Nenhum paciente tinha outro fator de risco para infecçäo, além das transfusöes. Cada pacientes soropositivo foi comparado com três controles soronegativos, pareados por sexo. O número médio de transfusöes foi de 29,3 unidades para os casos e 26,7 unidades para os controles. O tempo médio de diálise foi de 28,2 e 27,2 meses para casos e controles, respectivamente. O risco de infecçäo pelo HIV näo foi associado ao número de transfusöes ou ao tempo de diálise. A relaçäo OKT/OKT foi menor ou igual a um em todos os pacientes infectados