A 71-year-old man with a 21-year history of end stage kidney disease secondary to type 1 diabetes mellitus, status post combined kidney and pancreas transplantation on mycophenolate mofetil, tacrolimus and prednisone, presented with worsening left-sided arm and leg weakness for three weeks. He denied other symptoms, including tingling, numbness, fevers, chills, and changes in vision.

Vital signs were stable (HR: 92 bpm, BP: 134/88 mm Hg, RR: 16 bpm, Temp: 37.1 °C). Examination was notable for 4/5 left upper and lower extremity strength. He was attentive, alert, and oriented to person, place, and time. Magnetic Resonance Imaging of the brain discovered a right parieto-temporal mass lesion with surrounding edema concerning for a malignancy (Image A, Red arrow). However, subsequent Positron Emission Tomography/Computed Tomography of chest, abdomen, and pelvis showed no fluorodeoxyglucose-positive lesions.

Five days later, his mental status acutely deteriorated with decreased attentiveness and disorientation. Repeat Magnetic Resonance Imaging revealed an acute right temporal lobe infarct with transtentorial herniation, requiring urgent resection of the mass lesion. Histopathologic examination of the mass showed *toxoplasma* cystozoites (Image B, White arrow) and tachyzoites. Human Immunodeficiency Virus serology was negative.

Toxoplasma IgG antibody titers were positive. Immunosuppression was discontinued, pyrimethamine-sulfadiazine was initiated, and he was discharged 2 weeks later. Toxoplasma gondii infection is a potentially life-threatening complication associated with solid organ transplantation. This infection can result either from transmission from a Toxoplasma seropositive donor or from reactivation of latent infection in a recipient. Routine use of trimethoprim/sulfamethoxazole for *pneumocystis jirovecii* prophylaxis may prevent this complication, but infection can develop after prophylaxis discontinuation.

In immunocompromised patients, cerebral toxoplasmosis may present with a solitary brain lesion that may closely mimic brain malignancy. It is important to maintain a high index of clinical suspicion and institute early and appropriate treatment to prevent a poor outcome.

Conflicts of interest {#sec0005}
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The authors have no conflicts of interest.

Sources of funding {#sec0010}
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The authors have no funding source to disclose.

Consent {#sec0015}
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Patient is deceased. There is no patient identifying information in this article.

Author contribution {#sec0020}
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Both authors contributed to the conception, drafting, and revision of the article.
