Fatal Granulomatous Amebic Encephalitis in a Heart Transplant Patient: Clinical, Radiographic, and Autopsy Findings

Area of Science:

• Neurology
• Infectious Diseases
• Immunology

Background:

• Granulomatous amebic encephalitis (GAE) is a rare, fatal necrotizing infection of the central nervous system (CNS).
• It predominantly affects immunocompromised individuals and is often misdiagnosed due to non-specific clinical and radiographic findings.
• Differential diagnoses typically include other CNS infections like bacterial, viral, fungal, or protozoal pathogens.

Observation:

• A case of a 69-year-old heart transplant recipient experiencing rapid neurological deterioration approximately 5 months post-transplant.
• Extensive diagnostic workup, including radiographic and laboratory tests, failed to yield a definitive diagnosis.
• The patient succumbed to the illness, with autopsy revealing numerous brain abscesses containing Acanthamoeba trophozoites and cysts.

Findings:

• Autopsy confirmed the presence of Acanthamoeba species via indirect immunofluorescence assay.
• This represents the 14th reported case of Acanthamoeba encephalitis in solid organ transplant recipients and the second in a heart transplant recipient.
• The findings highlight the diagnostic challenges and fatal nature of GAE in this population.

Implications:

• GAE should be included in the differential diagnosis for immunocompromised patients presenting with new CNS lesions.
• Early recognition and diagnostic consideration of Acanthamoeba are critical for improving outcomes in transplant recipients.
• This case underscores the importance of considering rare opportunistic infections in the evolving landscape of post-transplant care.