biostudies-literatureHirakata SResearch Committee for Applying Health and Technology of the Ministry of Health, Welfare and LabourJSPS KAKENHINervous and Mental Disorders392https://www.ebi.ac.uk/biostudies/studies/S-EPMC8501540biostudies-literatureUnknown21(1)<h4>Background</h4>Granulomatous amoebic encephalitis (GAE) is an infrequent and fatal infectious disease worldwide. Antemortem diagnosis in this condition is very difficult because clinical manifestations and neuroimaging are nonspecific.<h4>Case presentation</h4>A 60-year-old Japanese woman was admitted with a chief complaint of left homonymous hemianopsia. Brain-MRI showed extensive necrotizing lesions enhanced by gadolinium, in the right frontal lobe, right occipital lobe, and left parietal lobe. Epithelioid granulomas of unknown etiology were found in the biopsied brain specimens. Shotgun metagenomic sequencing using a next-generation sequencer detected DNA fragments of Balamuthia mandrillaris in the tissue specimens. The diagnosis of granulomatous amoebic encephalitis was confirmed using an amoeba-specific polymerase chain reaction and immunostaining on the biopsied tissues.<h4>Conclusions</h4>Shotgun metagenomics is useful for the diagnosis of central nervous system infections such as GAE wherein the pathogens are difficult to identify.BMC neurologyThe application of shotgun metagenomics to the diagnosis of granulomatous amoebic encephalitis due to Balamuthia mandrillaris: a case report.PMC8501540JP19K17013Matsuura EHigashi MYoshimura MHatanaka MYagita KTakashima HYonezawa HSakiyama YArata HYoshimura ATakahata KKirishima MTashiro YIkeda MHirakata SKanekura TfalseThe application of shotgun metagenomics to the diagnosis of granulomatous amoebic encephalitis due to Balamuthia mandrillaris: a case report.<h4>Background</h4>Granulomatous amoebic encephalitis (GAE) is an infrequent and fatal infectious disease worldwide. Antemortem diagnosis in this condition is very difficult because clinical manifestations and neuroimaging are nonspecific.<h4>Case presentation</h4>A 60-year-old Japanese woman was admitted with a chief complaint of left homonymous hemianopsia. Brain-MRI showed extensive necrotizing lesions enhanced by gadolinium, in the right frontal lobe, right occipital lobe, and left parietal lobe. Epithelioid granulomas of unknown etiology were found in the biopsied brain specimens. Shotgun metagenomic sequencing using a next-generation sequencer detected DNA fragments of Balamuthia mandrillaris in the tissue specimens. The diagnosis of granulomatous amoebic encephalitis was confirmed using an amoeba-specific polymerase chain reaction and immunostaining on the biopsied tissues.<h4>Conclusions</h4>Shotgun metagenomics is useful for the diagnosis of central nervous system infections such as GAE wherein the pathogens are difficult to identify.2021-01-01T00:00:00Z2021 Oct2025-04-22T11:27:26.901Z2025-04-05T23:58:46.788ZS-EPMC85015403462718310.1186/s12883-021-02418-y