Leptomeningeal toxoplasmosis after allogeneic marrow transplantation. Case report and review of the literature.

A 37-year-old woman with chronic myelogenous leukemia underwent allogeneic bone marrow transplantation with CD8-depleted marrow from an HLA-identical sister. On day 43 post-transplant, the patient developed a headache and became lethargic and tremulous. Magnetic resonance imaging (MRI) of the brain showed abnormal meningeal and superficial parenchymal enhancement anteriorly. The spinal fluid had an elevated protein level with normal glucose and a neutrophilic pleocytosis. At autopsy, Toxoplasma meningoencephalitis was seen. On review of the literature, headache and confusion at 1-2 months post-transplant are common presenting signs of central nervous system toxoplasmosis. The predominance of neutrophils in the spinal fluid in this patient probably reflects the meningeal component of the infection and is an unusual finding. The presentation of toxoplasmosis in marrow transplant recipients is quite pleomorphic, and a definite diagnosis is difficult to obtain antemortem. Empiric therapy with pyrimethamine and sulfadiazine should be considered for marrow transplant recipients with neurologic deficits for which there is no other apparent etiology.