{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,21]],"date-time":"2026-02-21T07:01:09Z","timestamp":1771657269810,"version":"3.50.1"},"reference-count":25,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T00:00:00Z","timestamp":1753228800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Cat bites frequently lead to polymicrobial infections due to deep puncture wounds that inoculate oral flora into poorly oxygenated tissues. While Pasteurella multocida is the most commonly implicated organism, environmental and atypical pathogens may also play a role, yet often go unrecognized. This article reports a rare case of polymicrobial septic arthritis caused by a domestic cat bite in an immunocompetent adult, with isolation of Rahnella aquatilis, a freshwater-associated Enterobacterales species not previously reported in this context. A 33-year-old immunocompetent male presented with acute hand swelling, pain, and functional impairment within 24 h of the bite. Emergency surgery revealed purulent tenosynovitis and arthritis. Intraoperative cultures identified R. aquatilis, P. multocida, and Pantoea agglomerans. Identification was performed using MALDI-TOF MS. The R. aquatilis isolate was susceptible to beta-lactams (excluding ampicillin), quinolones, and co-trimoxazole. The patient received amoxicillin\u2013clavulanic acid and fully recovered within two weeks. This is the first reported case of joint infection involving R. aquatilis following a cat bite. It highlights the importance of considering environmental Enterobacterales in animal bite wounds, and the utility of advanced microbiological tools for detecting uncommon pathogens. Broader awareness may improve diagnosis and guide targeted therapy in polymicrobial infections.<\/jats:p>","DOI":"10.3390\/microorganisms13081725","type":"journal-article","created":{"date-parts":[[2025,7,23]],"date-time":"2025-07-23T14:22:44Z","timestamp":1753280564000},"page":"1725","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Polymicrobial Arthritis Following a Domestic Cat Bite Involving Rahnella aquatilis in an Immunocompetent Patient"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-1372-4879","authenticated-orcid":false,"given":"Olivier","family":"Nicod","sequence":"first","affiliation":[{"name":"Department of Orthopedics, Iris Hospitals South, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4915-1339","authenticated-orcid":false,"given":"Marie","family":"Tr\u00e9-Hardy","sequence":"additional","affiliation":[{"name":"Universit\u00e9 libre de Bruxelles, 1050 Brussels, Belgium"},{"name":"Department of Pharmacy, Namur Research Institute for Life Sciences, University of Namur, 5000 Namur, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Bruno","family":"Baillon","sequence":"additional","affiliation":[{"name":"Department of Orthopedics, Iris Hospitals South, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0552-1775","authenticated-orcid":false,"given":"Ingrid","family":"Beukinga","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Iris Hospitals South, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5968-5847","authenticated-orcid":false,"given":"William","family":"Ngatchou","sequence":"additional","affiliation":[{"name":"Department of Laboratory Medicine, Iris Hospitals South, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Nada","family":"Riahi","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Iris Hospitals South, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0304-7624","authenticated-orcid":false,"given":"Laurent","family":"Blairon","sequence":"additional","affiliation":[{"name":"Department of Emergency Medicine, Iris Hospitals South, 1050 Brussels, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,7,23]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"47","DOI":"10.5435\/JAAOS-23-01-47","article-title":"Human and other mammalian bite injuries of the hand: Evaluation and management","volume":"23","author":"Kennedy","year":"2015","journal-title":"J. Am. Acad. Orthop. Surg."},{"key":"ref_2","first-page":"239","article-title":"Dog and cat bites","volume":"90","author":"Ellis","year":"2014","journal-title":"Am. Fam. Physician"},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"85","DOI":"10.1056\/NEJM199901143400202","article-title":"Bacteriologic analysis of infected dog and cat bites","volume":"340","author":"Talan","year":"1999","journal-title":"N. Engl. J. Med."},{"key":"ref_4","first-page":"1649","article-title":"Pasteurella multocida infectious arthritis with acute gout after a cat bite","volume":"24","author":"Butt","year":"1997","journal-title":"J. Rheumatol."},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Alifragki, A., Kontogianni, A., Protopapa, I., Baliou, S., and Ioannou, P. (2022). Infective endocarditis by Pasteurella species: A systematic review. J. Clin. Med., 11.","DOI":"10.3390\/jcm11175037"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"125","DOI":"10.1007\/s10096-022-04520-6","article-title":"Osteomyelitis caused by Pasteurella multocida and Bacteroides pyogenes after cat bite","volume":"42","author":"Vecilla","year":"2023","journal-title":"Eur. J. Clin. Microbiol. Infect. Dis."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"2050313X231222217","DOI":"10.1177\/2050313X231222217","article-title":"Unique presentation of an intramuscular abscess caused by Bacteroides pyogenes in the setting of a cat bite: A case report","volume":"12","author":"Sadhwani","year":"2024","journal-title":"SAGE Open Med. Case Rep."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"3092","DOI":"10.1128\/JCM.00250-11","article-title":"Bacteremia with Bacteroides pyogenes after a cat bite","volume":"49","author":"Madsen","year":"2011","journal-title":"J. Clin. Microbiol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1128\/JCM.42.1.290-293.2004","article-title":"Isolation of a fastidious Bergeyella species associated with cellulitis after a cat bite and a phylogenetic comparison with Bergeyella zoohelcum strains","volume":"42","author":"Shukla","year":"2004","journal-title":"J. Clin. Microbiol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"171","DOI":"10.3201\/eid0802.010139","article-title":"Clinical significance and epidemiology of NO-1, an unusual bacterium associated with dog and cat bites","volume":"8","author":"Kaiser","year":"2002","journal-title":"Emerg. Infect. Dis."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"428","DOI":"10.1016\/j.rvsc.2012.11.003","article-title":"Novel bacterial phylotypes associated with the healthy feline oral cavity and feline chronic gingivostomatitis","volume":"94","author":"Dolieslager","year":"2013","journal-title":"Res. Vet. Sci."},{"key":"ref_12","first-page":"317","article-title":"\u00c9tude taxonomique d\u2019ent\u00e9robact\u00e9ries appartenant ou apparent\u00e9es au genre Enterobacter","volume":"127B","author":"Gavini","year":"1976","journal-title":"Ann. Microbiol. (Inst. Pasteur.)"},{"key":"ref_13","first-page":"463","article-title":"Characterization of the oral microbiota of healthy cats using next-generation sequencing","volume":"202","author":"Sturgeon","year":"2014","journal-title":"Vet. J."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"471","DOI":"10.1080\/00365540152029972","article-title":"Rahnella aquatilis bacteremia in a patient with relapsed acute lymphoblastic leukemia","volume":"33","author":"Carinder","year":"2001","journal-title":"Scand. J. Infect. Dis."},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1016\/0732-8893(95)00100-O","article-title":"Rahnella aquatilis bacteremia in an HIV-infected intravenous drug abuser","volume":"22","author":"Funke","year":"1995","journal-title":"Diagn. Microbiol. Infect. Dis."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"79","DOI":"10.3109\/00365549509018979","article-title":"Bacteraemia caused by Rahnella aquatilis: Report of two cases and review","volume":"27","author":"Oh","year":"1995","journal-title":"Scand. J. Infect. Dis."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"e930888-1","DOI":"10.12659\/AJCR.930888","article-title":"Septic shock caused by Rahnella aquatilis bacteremia in an immunocompetent adult","volume":"22","author":"Roeder","year":"2021","journal-title":"Am. J. Case Rep."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"4161","DOI":"10.1128\/JCM.37.12.4161-4162.1999","article-title":"Rahnella aquatilis sepsis in an immunocompetent adult","volume":"37","author":"Chang","year":"1999","journal-title":"J. Clin. Microbiol."},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"648","DOI":"10.1016\/j.bjid.2015.07.009","article-title":"Co-transmission of Rahnella aquatilis between hospitalized patients","volume":"19","author":"Martins","year":"2015","journal-title":"Braz. J. Infect. Dis."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"889","DOI":"10.1111\/jfd.13200","article-title":"First report on the characterization of pathogenic Rahnella aquatilis KCL-5 from crucian carp: Revealed by genomic and proteomic analyses","volume":"43","author":"Liang","year":"2020","journal-title":"J. Fish Dis."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"280","DOI":"10.1007\/s11999-015-4367-x","article-title":"In Brief: Kanavel\u2019s Signs and Pyogenic Flexor Tenosynovitis","volume":"474","author":"Kennedy","year":"2016","journal-title":"Clin. Orthop. Relat. Res."},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Medeiros, I., and Saconato, H. (2001). Antibiotic prophylaxis for mammalian bites. Cochrane Database Syst. Rev., CD001738.","DOI":"10.1002\/14651858.CD001738"},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"859","DOI":"10.1111\/j.1445-1433.2004.03189.x","article-title":"Cat bites of the hand","volume":"74","author":"Mitnovetski","year":"2004","journal-title":"ANZ J. Surg."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"341","DOI":"10.1080\/2000656X.2019.1637750","article-title":"Cat bite: An injury not to underestimate","volume":"53","author":"Kheiran","year":"2019","journal-title":"J. Plast. Surg. Hand Surg."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"5002","DOI":"10.1128\/JB.00542-10","article-title":"The human oral microbiome","volume":"192","author":"Dewhirst","year":"2010","journal-title":"J. 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