{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,20]],"date-time":"2026-01-20T15:41:56Z","timestamp":1768923716593,"version":"3.49.0"},"reference-count":44,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2021,7,12]],"date-time":"2021-07-12T00:00:00Z","timestamp":1626048000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["CIMB"],"abstract":"<jats:p>Lacrimal canaliculitis is a rare infection of the lacrimal canaliculi with canalicular concretions formed by aggregation of organisms. Metagenomic shotgun sequencing analysis using next-generation sequencing has been used to detect pathogens directly from clinical samples. Using this technology, we report cases of successful pathogen detection of canalicular concretions in lacrimal canaliculitis cases. We investigated patients with primary lacrimal canaliculitis examined in the eye clinics of four hospitals from February 2015 to July 2017. Eighteen canalicular concretion specimens collected from 18 eyes of 17 patients were analyzed by shotgun metagenomics sequencing using the MiSeq platform (Illumina). Taxonomic classification was performed using the GenBank NT database. The canalicular concretion diversity was characterized using the Shannon diversity index. This study included 18 eyes (17 patients, 77.1 \u00b1 6.1 years): 82.4% were women with lacrimal canaliculitis; canalicular concretions were obtained from 12 eyes using lacrimal endoscopy and six eyes using canaliculotomy with curettage. Sequencing analysis detected bacteria in all samples (Shannon diversity index, 0.05\u20131.47). The following genera of anaerobic bacteria (&gt;1% abundance) were identified: Actinomyces spp. in 15 eyes, Propionibacterium spp., Parvimonas spp. in 11 eyes, Prevotella spp. in 9 eyes, Fusobacterium spp. in 6 eyes, Selenomonas spp. in 5 eyes, Aggregatibacter spp. in 3 eyes, facultative and aerobic bacteria such as Streptococcus spp. in 13 eyes, Campylobacter spp. in 6 eyes, and Haemophilus spp. in 3 eyes. The most common combinations were Actinomyces spp. and Streptococcus spp. and Parvinomonas spp. and Streptococcus spp., found in 10 cases. Pathogens were identified successfully using metagenomic shotgun sequencing analysis in patients with canalicular concretions. Canalicular concretions are polymicrobial with anaerobic and facultative, aerobic bacteria.<\/jats:p>","DOI":"10.3390\/cimb43020049","type":"journal-article","created":{"date-parts":[[2021,7,12]],"date-time":"2021-07-12T21:56:52Z","timestamp":1626127012000},"page":"676-686","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Metagenomic Shotgun Sequencing Analysis of Canalicular Concretions in Lacrimal Canaliculitis Cases"],"prefix":"10.3390","volume":"43","author":[{"given":"Yukinobu","family":"Okajima","sequence":"first","affiliation":[{"name":"Department of Ophthalmology, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Takashi","family":"Suzuki","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Chika","family":"Miyazaki","sequence":"additional","affiliation":[{"name":"Hyogo Prefectural Amagasaki General Medical Center, 2-17-77 Higashi-nanba cho, Amagasaki 661-0892, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Satoshi","family":"Goto","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, School of Medicine, The Jikei University, 3-19-18 Shinbashi-nishi, Minato-ku, Tokyo 105-8471, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8729-7286","authenticated-orcid":false,"given":"Sho","family":"Ishikawa","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, School of Medicine, Saitama University, 38 Morohongo Moroyama-machi, Iruma-gun, Saitama 350-0495, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuka","family":"Suzuki","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9237-1217","authenticated-orcid":false,"given":"Kotaro","family":"Aoki","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Infectious Diseases, School of Medicine, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yoshikazu","family":"Ishii","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Infectious Diseases, School of Medicine, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kazuhiro","family":"Tateda","sequence":"additional","affiliation":[{"name":"Department of Microbiology and Infectious Diseases, School of Medicine, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3781-7976","authenticated-orcid":false,"given":"Yuichi","family":"Hori","sequence":"additional","affiliation":[{"name":"Department of Ophthalmology, Toho University, 6-11-1 Omori-nishi, Ota-ku, Tokyo 143-8541, Japan"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1016\/j.survophthal.2010.12.001","article-title":"Primary and secondary lacrimal canaliculitis: A review of literature","volume":"56","author":"Freedman","year":"2011","journal-title":"Surv. 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