Toxoplasma gondii pneumonia in patients with the acquired immunodeficiency syndrome

To perform a retrospective and descriptive study of Toxoplasma gondii pneumonia in patients infected with the human immunodeficiency virus (HIV). Clinical presentation, diagnostic procedures, results of therapy, and hypotheses on pathophysiology are discussed.

The study consisted of 13 HIV-infected patients who had developed T. gondii pneumonia. Eight had acquired immunodeficiency syndrome (AIDS) prior to T. gondii pneumonia and three of them had non-Hodgkin's lymphoma. Mean CD4 cell count was 32 x 10(6)/L. Serum anti-toxoplasma antibody titers were measured by an indirect hemagglutination assay and/or by an indirect immunofluorescence assay.

All patients had fever and bilateral pulmonary infiltrates; two of them presented with septic shock. Mean arterial oxygen tension was 47 +/- 12 mm Hg. The diagnosis was established by bronchoalveolar lavage in 10 of 11 cases, open lung biopsy in one case, and postmortem biopsy in two cases. Serologic evidence of past infection was observed in 11 of 12 cases, while one patient presented with acute disseminated disease and absence of serum anti-toxoplasma antibody response. Extrapulmonary involvement was present in seven patients: liver (four), brain (three), bone marrow (two), heart (two), stomach (one). Ten patients recovered from T. gondii pneumonia.

T. gondii pneumonia must be considered in AIDS patients with severe diffuse bilateral pneumonia, especially when associated with a very low CD4 cell count or non-Hodgkin's lymphoma. In most of these cases, disseminated disease was associated with reactivation of prior latent infection.