# Cerebral Toxoplasmosis in a Renal Transplant Recipient—A Rare Complication

## TL;DR

A kidney transplant recipient developed cerebral toxoplasmosis, a rare infection, which was misdiagnosed initially but later confirmed through testing and treatment.

## Contribution

This paper presents a rare case of cerebral toxoplasmosis in a renal transplant recipient and emphasizes the importance of early diagnosis and treatment.

## Key findings

- Cerebral toxoplasmosis was confirmed in a renal transplant recipient through histopathology and PCR testing.
- The patient showed neurological improvement with anti-toxoplasma therapy but later died from urosepsis.
- The case highlights the diagnostic challenges of cerebral toxoplasmosis, which can mimic brain tumors.

## Abstract

Cerebral toxoplasmosis is a rare but potentially fatal opportunistic infection in renal transplant recipients receiving long-term immunosuppressive therapy. It may result from donor-derived transmission or reactivation of latent infection. We report the case of a 70-year-old female who underwent kidney transplantation from a deceased donor in 2004 for end-stage renal disease due to glomerulonephritis. She was maintained on cyclosporine, mycophenolate mofetil, and prednisone. In September 2024, she presented with headache, mood changes, and right-sided hemiparesis. Brain multislice computed tomography revealed a large temporoparietal lesion initially suspected to be glioblastoma. Craniotomy and histopathological analysis demonstrated encysted Toxoplasma gondii bradyzoites within gliotic tissue. Polymerase chain reaction testing confirmed the presence of T. gondii DNA, while human immunodeficiency virus testing was negative. The patient reported frequent contact with domestic cats. Treatment with pyrimethamine, sulfadiazine, and leucovorin, alongside adjustment of immunosuppressive therapy, led to marked neurological improvement and radiological regression of the lesion. However, nine months later, she succumbed to multidrug-resistant urosepsis. This case highlights the diagnostic challenges of cerebral toxoplasmosis in transplant recipients, as radiological findings are often nonspecific and can mimic neoplastic or lymphoproliferative lesions. Polymerase chain reaction and histopathological analysis remain essential for definitive diagnosis. Awareness of this rare complication is critical for early recognition and prompt initiation of anti-toxoplasma therapy, which can significantly improve outcomes. Although cerebral toxoplasmosis is uncommon after kidney transplantation, it should be considered in immunosuppressed patients presenting with neurological symptoms. Early detection and targeted therapy are key to reducing morbidity and mortality in this population.