Amoebic Encepha l itis Caused by Balamuthia mandrillaris

Abstract

We present the case of a 71 year old male who was diagnosed with amoebic encephalitis caused by Balamuthia mandrillaris . He had rheumatic arthritis for 30 years and had undergone continuous tr eatment with immunosuppressants. First, he complained of partial spasm from the left thigh to the left upper limb. Magnetic resonance imaging revealed multifocal enhancing nodules in the cortical and subcortical area of both cerebral hemispheres, which wer e suggestive of brain metastases. However, the patient developed fever with stuporous mentality and an open biopsy was performed immediately. Microscopically, numerous amoebic trophozoites measuring 20 to 25 m in size, with nuclei containing one to four nucleoli and some scattered cysts having a double  layered wall were noted in the background of hemorrhagic necrosis. Based on the microscopic findings , amoebic encephalitis caused by Balamuthia mandrillaris was diagnosed. The patient died on the 10th day after being admitted at the hospital . The diagnosis of amoebic encephalitis in the early stage is difficult for clinicians. Moreover, most cases undergo rapid deterioration, resulting in fatal consequences. In th is report, we present the first case of Balamuthia mandrillaris amoebic encephalitis with fatal progression in a Korean patient.