Blastocystis hominis in Hepatic Abscesses: Innocent Bystander or Hidden Culprit? A Case Report and Literature Review

Blastocystis hominis is a ubiquitous intestinal parasite commonly detected in human stools. Queries about the pathogenic nature of B. hominis in immunocompetent individuals have been raised with conflicting reports about the clinical significance of detecting the parasites in various specimens. Cases of invasive intestinal infections and identification of Blastocystis species in a splenic cyst and hepatic abscess have previously been reported. We present the case of a 65-year-old man with history of recent travel to a tropical country who was found to have multiple hepatic abscesses. Analysis of the hepatic abscess fluid confirmed the presence of Entamoeba species and B. hominis. To our knowledge, this is the second reported case in which B. hominis was identified with E. histolytica in a liver abscess, which may provide additional information about the infective potential of the parasite. However, further studies are required to confirm the pathogenicity of B. hominis, including molecular investigations into the various genetic subtypes.