title: Diagnosis of first case of Balamuthia amoebic encephalitis in Portugal by immunofluorescence and PCR.
abstract: We report here the first Portuguese case of acute fatal granulomatous encephalitis attributed to Balamuthia mandrillaris, initially thought to be a brain tumor, which had a progressive and fatal outcome. Balamuthia mandrillaris is a free-living amoeba recognized as an uncommon agent of granulomatous encephalitis. Infections have been identified in immunocompromised hosts and in immunocompetent pediatric patients. Balamuthia infections are very rare, with only two reported cases in Europe. The case presented here occurred in a previously healthy boy who died 5 weeks after the onset of the symptoms. No evidence of immunological deficiency was noted, and testing for human immunodeficiency virus antibodies was negative. The symptoms were initially thought to be the result of a tumor, but histopathologic examination showed evidence of amoebic infection. Immunofluorescence staining of brain tissue identified B. mandrillaris as the infectious agent. The diagnosis was confirmed with PCR by detecting Balamuthia DNA in formalin-fixed brain tissue sections. Despite initiation of empirical antimicrobial therapy for balamuthiasis, the patient died 3 weeks after being admitted to the hospital. No source of infection was readily apparent.
authors.affiliation: Department of Pediatrics, Hospital de S. João, Porto, Portugal.
authors.forename: Marta
authors.initials: M
authors.lastname: Tavares
authors.forename: Jose M
authors.initials: JM
authors.lastname: Correia da Costa
authors.forename: S Stirling
authors.initials: SS
authors.lastname: Carpenter
authors.forename: L A
authors.initials: LA
authors.lastname: Santos
authors.forename: Caldas
authors.initials: C
authors.lastname: Afonso
authors.forename: Alvaro
authors.initials: A
authors.lastname: Aguiar
authors.forename: Josue
authors.initials: J
authors.lastname: Pereira
authors.forename: Ana Isabel
authors.initials: AI
authors.lastname: Cardoso
authors.forename: Frederick L
authors.initials: FL
authors.lastname: Schuster
authors.forename: Shigeo
authors.initials: S
authors.lastname: Yagi
authors.forename: Rama
authors.initials: R
authors.lastname: Sriram
authors.forename: Govinda S
authors.initials: GS
authors.lastname: Visvesvara
mesh_terms: D000562:Amebiasis / Q000175:diagnosis*; D000818:Animals; D001921:Brain / Q000000981:diagnostic imaging / Q000473:pathology; D002648:Child; D004660:Encephalitis / Q000175:diagnosis*; D017809:Fatal Outcome; D005455:Fluorescent Antibody Technique; D006801:Humans; D016840:Lobosea / Q000235:genetics / Q000276:immunology / Q000302:isolation & purification*; D008297:Male; D016133:Polymerase Chain Reaction; D011174:Portugal; D011859:Radiography