Blastocystis sp. in splenic cysts: causative agent or accidental association? A unique case report.
BACKGROUND
Blastocystis sp. is one of the most prevalent parasites found in human stool and has been recently considered an opportunistic emerging pathogen in immunocompromised individuals. However, cases of invasive intestinal infections and skin rashes have been attributed to infection by Blastocystis sp in immunocompetent individuals, suggesting that it is an emerging parasite with pathogenic potential.


RESULTS
We present a case of a 22 year old female patient who complained of pain in the left hypochondrium. Ultrasonography and abdominal computed tomography scans showed two splenic cysts. The cyst fluid analysis demonstrated numerous Blastocystis sp.; PCR and DNA sequencing analyses confirmed the presence of Blastocystis subtype 3.


CONCLUSIONS
This is, to our knowledge, the first case report of the presence of Blastocystis subtype 3 in extra-intestinal organs and is strong evidence that Blastocystis sp. is potentially pathogenic and invasive. However, further studies are required to determine the pathogenicity of the parasite.
Laboratório de Avaliação e Promoção da Saúde Ambiental, Instituto Oswaldo Cruz/FIOCRUZ, Av, Brasil, 4365-Pavilhão Lauro Travassos, Manguinhos, Rio de Janeiro, RJ 21,045-900, Brazil. helenalucias@ioc.fiocruz.br.
Helena Lúcia Carneiro
HL
Santos
Fernando Campos
FC
Sodré
Heloisa Werneck
HW
de Macedo
D016844:Blastocystis / Q000235:genetics; D016776:Blastocystis Infections / Q000473:pathology*; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D010802:Phylogeny; D012335:RNA, Ribosomal / Q000235:genetics; D013158:Splenic Diseases / Q000469:parasitology*; D055815:Young Adult
D012335:RNA, Ribosomal