Balamuthia amoebic encephalitis directly causing intracranial infection: A case report

Abstract

Balamuthia amoebic encephalitis (BAE) is a rare and often fatal central nervous system (CNS) infection caused by Balamuthia mandrillaris, a free-living amoeba typically found in soil and water. This organism can invade the brain directly, bypassing other organs, making early diagnosis particularly challenging. Symptoms often do not appear as distinctive early warning signs, and many patients do not experience noticeable skin lesions or systemic symptoms before neurological manifestations emerge. Balamuthia can enter the body through various routes, including the respiratory tract, skin, or gastrointestinal tract, eventually crossing the blood-brain barrier and causing aggressive encephalitis. The early symptoms of BAE are nonspecific, and the disease has an extremely high mortality rate. This report presents a 35-year-old male patient who died from Balamuthia amoebic encephalitis. The patient had a history of prolonged exposure to underground mines and consumed raw beef a week before the onset of symptoms. The infection is believed to have entered through the respiratory tract or gastrointestinal route. Diagnosis was primarily based on pathological findings, and the patient did not receive effective treatment due to delayed diagnosis, ultimately passing away approximately 2 months after the onset of symptoms. This case emphasizes the rarity and fatal nature of BAE, particularly when neurological symptoms are the first sign of infection without preceding systemic or dermatological manifestations. The report highlights the importance of considering Balamuthia mandrillaris infection in patients presenting with unexplained encephalitis and brain abscess, especially with a potential history of exposure to amoeba-contaminated environments.