[Isolation of Toxoplasma gondii by cellular culture in HIV infected patients].

Nine hundred and eight biological samples obtained from HIV-infected patients were examined for Toxoplasma gondii by a tissue culture method. Sixty-two isolations of Toxoplasma gondii were made in 43 patients. Fourteen isolations were made from tissue biopsies (brain 4, striated muscle 2, liver 1), bone marrow aspirates (4 cases), pericardial or pleural effusions (3 cases) and vitreous body (1). In 6 cases, a parasitic dissemination was evidenced by the demonstration of Toxoplasma in blood or other tissues or body fluids. Toxoplasma organisms were demonstrated in the bronchoalveolar lavage fluid of 19 patients; this was associated with a parasitaemia in 6 of the 10 patients whose blood sample was cultured at the same time. Among 273 blood samples cultured, 29 were positive for Toxoplasma (24 patients); all patients with parasitaemia had clinical symptoms, but only 8 of them had clinical or radiological symptoms suggestive of a cerebral localization; this suggests that the presence of a parasitaemia is fairly indicative of an extra cerebral localization of toxoplasmosis. In 11 patients, blood was examined after treatment was initiated; in 8 patients parasitaemia was undetectable at the first examination after treatment (1 to 15 days after initiation of therapy), whereas in 3 patients sampled 1, 4 or 6 days respectively after treatment a persistent parasitaemia could be demonstrated. These results clearly show that the tissue culture method is efficient and sensitive to provide an early evidence of infection (4 days), and may prove useful to evaluate therapeutic effectiveness.