B. mandrillaris, an amoeba.
Swimming in fresh water and soil. Has been transmitted with organ transplants.
And it has been spread in transplanted organs(Pubmed).
Meningoencephalitis (PubMed). Can be indolent with a granulomatous encephalitis and can mimic brain tumor.
"Survivors of Balamuthia infection were treated with a combination of antimicrobials, including pentamadine isothionate, 5-fluorocytosine (flucytosine), fluconazole, sulfadiazine, and a macrolide antibiotic (azithromycin or clarithromycin), with or without a phenothiazine compound (PubMed)."
See McCoy, Bones.