A Case of Toxoplasmic Encephalitis in an HIV-Negative Patient With Multiple Cerebral Infarction-Like Findings in the...

Toxoplasmic encephalitis (TE) is an opportunistic infection that typically manifests in immunocompromised individuals, such as those with HIV infection or AIDS. The characteristic imaging finding is a mass-like lesion with ring enhancement. We report a rare case of TE in a patient who was not infected with HIV with atypical imaging features. An 81-year-old woman developed progressive impaired consciousness over several weeks. Initially, the brain MRI revealed multiple lesions resembling cerebral infarctions, which gradually enlarged and increased in number. Subsequently, gadolinium-enhanced MRI showed ring-enhancing mass-like lesions in the pons and left parietal lobe. Blood tests indicated elevated inflammatory markers and a mildly increased Toxoplasma IgG level. Given the progressive course, empiric therapy with trimethoprim-sulfamethoxazole and clindamycin was initiated, leading to marked improvement in consciousness by the fourth day. Toxoplasma DNA was later detected in the blood, confirming the diagnosis of TE.