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

Granulomatous amebic encephalitis is a rare necrotizing infection of the CNS that occurs most commonly in immunocompromised individuals and is usually fatal. It is difficult to diagnose as the clinical symptoms and radiographic findings are often mistaken for other bacterial, viral, fungal, or protozoan infections. Herein, we present the case of a 69-year-old heart transplant recipient who suffered fulminant neurological decline ∼5 months after transplant. Extensive radiographic and laboratory testing did not provide a definite anatomic diagnosis and, despite aggressive clinical treatment, he died. An autopsy examination demonstrated numerous brain abscesses which contained amebic trophozoites and cysts. An indirect immunofluorescence assay performed at the Centers for Disease Control confirmed the presence of Acanthamoeba species. To the best of our knowledge, only 13 other cases of Acanthamoeba amebic encephalitis have been reported in patients who have received solid organ transplants and this is the second case reported in a heart transplant recipient. This case emphasizes that amebic encephalitis should be in the differential diagnosis for immunocompromised patients with new brain lesions found on radiographic imaging.