“Bacteroides denticanum” is an anaerobic, non-spore-forming, gram-negative bacterium with a rod morphology typical of canine, ovine, and macropod oral flora. There is only one report of bloodstream infection caused by “B. denticanum” from a dog bite in human. Here, we report a case with no history of animal contact who developed an abscess caused by “B. denticanum” around a pharyngo-esophageal anastomosis after undergoing balloon dilatation procedure for stenosis following laryngectomy. The patient was a 73-year-old man with laryngeal cancer, esophageal cancer, hyperuricemia, dyslipidemia, and hypertension with a 4-week history of cervical pain, sore throat, and fever. Computed tomography showed fluid collection on the posterior pharyngeal wall. Matrix-assisted laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) identified Bacteroides pyogenes, Lactobacillus salivarius, and Streptococcus anginosus from abscess aspiration. 16S ribosomal RNA sequencing re-identified the Bacteroides species as “B. denticanum”. T2-weighted magnetic resonance images showed a high signal intensity adjacent to the anterior vertebral body of C3–C7. The diagnosis was peripharyngeal esophageal anastomotic abscess and acute vertebral osteomyelitis caused by “B. denticanum”, L. salivarius, and S. anginosus. The patient was treated with sulbactam ampicillin intravenously for 14 days and then switched to oral amoxicillin with clavulanic acid for 6 weeks. To our knowledge, this is the first report of a human infection caused by “B. denticanum” without a history of animal contact. Despite remarkable advancements facilitated by MALDI-TOF MS in microbiological diagnosis, the accurate identification of novel, emerging, or uncommon microorganisms and comprehending their pathogenicity, suitable therapy, and follow up necessitate sophisticated molecular approaches.
Abbreviations:16S rRNA (16S ribosomal RNA), CLSI (Clinical and Laboratory Standards), CVA/AMPC (amoxicillin clavulanic acid), MALDI-TOF MS (matrix-assisted laser desorption ionization-time-of-flight mass spectrometry), SBT/ABPC (ampicillin-sulbactam)
To read this article in full you will need to make a payment
Purchase one-time access:Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
One-time access price info
- For academic or personal research use, select 'Academic and Personal'
- For corporate R&D use, select 'Corporate R&D Professionals'
Subscribe:Subscribe to Journal of Infection and Chemotherapy
Already a print subscriber? Claim online access
Already an online subscriber? Sign in
Register: Create an account
Institutional Access: Sign in to ScienceDirect
- Bacteroides: the good, the bad, and the nitty-gritty.Clin Microbiol Rev. 2007; 20: 593-621https://doi.org/10.1128/CMR.00008-07
- Pigmented-anaerobic bacteria associated with canine periodontitis.Vet Microbiol. 2005; 106: 119-128https://doi.org/10.1016/j.vetmic.2004.12.018
- Bacteroides plebeius sp. nov. and Bacteroides coprocola sp. nov., isolated from human faeces.Int J Syst Evol Microbiol. 2005; 55: 2143-2147https://doi.org/10.1099/ijs.0.63788-0
- Species “Bacteroides denticanum”.https://lpsn.dsmz.de/species/bacteroides-denticanumDate accessed: March 28, 2023
- The canine oral microbiome.PLoS One. 2012; 7e36067https://doi.org/10.1371/journal.pone.0036067
- Culture-independent identification of bacteria associated with ovine ‘broken mouth’ periodontitis.Vet Microbiol. 2013; 166: 664-669https://doi.org/10.1016/j.vetmic.2013.06.034
- The oral microbial community of gingivitis and lumpy jaw in captive macropods.Res Vet Sci. 2013; 95: 996-1005https://doi.org/10.1016/j.rvsc.2013.08.010
- Bloodstream infection caused by Bacteroides denticanum, a close relative of Bacteroides pyogenes, misidentified by MALDI TOF-mass spectrometry.Anaerobe. 2018; 54: 23-25https://doi.org/10.1016/j.anaerobe.2018.06.010
- Jaw osteomyelitis and myositis caused by Bacteroides pyogenes.Anaerobe. 2023; 79102670https://doi.org/10.1016/j.anaerobe.2022.102670
- Peptostreptococcus canis and Bacteroides pyogenes prosthetic joint infection.Enferm Infecc Microbiol Clín. 2019; 37 (English, Spanish): 347-348https://doi.org/10.1016/j.eimc.2018.05.004
- Osteomyelitis caused by Pasteurella multocida and Bacteroides pyogenes after cat bite.Eur J Clin Microbiol Infect Dis. 2023; 42: 125-128https://doi.org/10.1007/s10096-022-04520-6
- Infectious Diseases Society of America (IDSA) clinical practice guidelines for the diagnosis and treatment of native vertebral osteomyelitis in adults.Clin Infect Dis. 2015; 61 (2015): e26-e46https://doi.org/10.1093/cid/civ482
Published online: April 26, 2023
Accepted: April 23, 2023
Received in revised form: March 31, 2023
Received: February 16, 2023
Publication stageIn Press Corrected Proof
☆All authors meet the ICMJE authorship criteria. NI was involved in the literature review, planning, and writing of the manuscript. NI, NA, and TT were involved in the patient's care. All the authors interpreted the data, drafted and critically revised the manuscript, and approved the final version.
© 2023 Japanese Society of Chemotherapy and The Japanese Association for Infectious Diseases. Published by Elsevier Ltd. All rights reserved.