{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,11]],"date-time":"2026-07-11T15:08:24Z","timestamp":1783782504397,"version":"3.55.0"},"reference-count":41,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T00:00:00Z","timestamp":1757030400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Organization of Public Health (EODY)","award":["6264\/2024"],"award-info":[{"award-number":["6264\/2024"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Microorganisms"],"abstract":"<jats:p>Background\/Objectives: Neisseria meningitidis is a human-specific pathogen capable of causing life-threatening illnesses. Occasionally, it is recovered from unusual sites, other than the bloodstream or the central nervous system. Herein, we describe two rare manifestations due to N. meningitidis within a year (2024) in Greece. Methods: Atypical infection due to N. meningitidis was diagnosed in two different patients: Case-1 presented with an inflammatory swelling in the mid-line of the neck, and Case-2 presented with swelling of the left knee. Both patients had high fever and no neurological signs at admission; Case-2 progressed to meningoencephalitis. Phenotypic and genotypic identifications were carried out in both cases. Results: Case-1 and Case-2 isolates were identified as follows: MenX: 18, 25-44, F5-5, ST-823; 198cc and MenB: 7-1, 1, F3-3, ST-7460; 32cc for PorA, FetA and MLST, respectively. MenX was identified for the first time in Greece and finetyping revealed rare genotypic characteristics. Both isolates were susceptible to cefotaxime, ceftriaxone and rifampicin, while Case-2 isolate expressed reduced susceptibility to penicillin and resistance to ciprofloxacin. Both patients recovered fully. Conclusions: Although uncommon, N. meningitidis may be isolated from atypical sites and specimens. Clinicians and microbiologists should remain aware that meningococcus is a potential cause of infections beyond meningitis and septicaemia.<\/jats:p>","DOI":"10.3390\/microorganisms13092071","type":"journal-article","created":{"date-parts":[[2025,9,5]],"date-time":"2025-09-05T12:18:18Z","timestamp":1757074698000},"page":"2071","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Two Cases of Rare Manifestations Due to Neisseria meningitidis During the Post-COVID-19 Era in Greece"],"prefix":"10.3390","volume":"13","author":[{"given":"Kalliopi","family":"Avgoulea","sequence":"first","affiliation":[{"name":"National Meningitis Reference Laboratory, Department of Public Health Policy, School of Public Health, University of West Attica, 196, Alexandras Avenue, 11521 Athens, Greece"},{"name":"Laboratory of Clinical Microbiology, General Hospital of Athens \u201cG. Gennimatas\u201d, 154, Mesogeion Avenue, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0000-8419-8031","authenticated-orcid":false,"given":"Genovefa","family":"Chronopoulou","sequence":"additional","affiliation":[{"name":"Central Laboratory, Athens Medical Center, Distomou 5-7, 15125 Marousi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-2959-8216","authenticated-orcid":false,"given":"Athanasia","family":"Xirogianni","sequence":"additional","affiliation":[{"name":"National Meningitis Reference Laboratory, Department of Public Health Policy, School of Public Health, University of West Attica, 196, Alexandras Avenue, 11521 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4553-8467","authenticated-orcid":false,"given":"Stelmos","family":"Simantirakis","sequence":"additional","affiliation":[{"name":"National Meningitis Reference Laboratory, Department of Public Health Policy, School of Public Health, University of West Attica, 196, Alexandras Avenue, 11521 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Theano","family":"Georgakopoulou","sequence":"additional","affiliation":[{"name":"Department of Vaccine Preventable Diseases, National Public Health Organization (NPHO), 15123 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anastasios","family":"Tsakalos","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology, General Hospital of Athens \u201cG. Gennimatas\u201d, 154, Mesogeion Avenue, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9538-5868","authenticated-orcid":false,"given":"Constantinos","family":"Karamalis","sequence":"additional","affiliation":[{"name":"National Meningitis Reference Laboratory, Department of Public Health Policy, School of Public Health, University of West Attica, 196, Alexandras Avenue, 11521 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lampros","family":"Nikolopoulos","sequence":"additional","affiliation":[{"name":"Neurology Department, General Hospital of Athens \u201cG. Gennimatas\u201d, 154, Mesogeion Avenue, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fotios","family":"Roussos","sequence":"additional","affiliation":[{"name":"Neurology Department, General Hospital of Athens \u201cG. Gennimatas\u201d, 154, Mesogeion Avenue, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maria","family":"Gryllia","sequence":"additional","affiliation":[{"name":"Neurology Department, General Hospital of Athens \u201cG. Gennimatas\u201d, 154, Mesogeion Avenue, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0009-0009-9601-0935","authenticated-orcid":false,"given":"Nektarios","family":"Marmaras","sequence":"additional","affiliation":[{"name":"Central Laboratory, Athens Medical Center, Distomou 5-7, 15125 Marousi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Efterpi","family":"Oikonomou","sequence":"additional","affiliation":[{"name":"Second Pediatric Department, Athens Medical Center, Distomou 5-7, 15125 Marousi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Diagoras","family":"Zarganis","sequence":"additional","affiliation":[{"name":"Second Pediatric Department, Athens Medical Center, Distomou 5-7, 15125 Marousi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0486-3666","authenticated-orcid":false,"given":"Maria","family":"Orfanidou","sequence":"additional","affiliation":[{"name":"Laboratory of Clinical Microbiology, General Hospital of Athens \u201cG. Gennimatas\u201d, 154, Mesogeion Avenue, 11527 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anastasia","family":"Pangalis","sequence":"additional","affiliation":[{"name":"Central Laboratory, Athens Medical Center, Distomou 5-7, 15125 Marousi, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0716-3174","authenticated-orcid":false,"given":"Muhamed-Kheir","family":"Taha","sequence":"additional","affiliation":[{"name":"Invasive Bacterial Infections, Institut Pasteur, 25-28 Rue du Docteur Roux, 75015 Paris, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1773-2833","authenticated-orcid":false,"given":"Georgina","family":"Tzanakaki","sequence":"additional","affiliation":[{"name":"National Meningitis Reference Laboratory, Department of Public Health Policy, School of Public Health, University of West Attica, 196, Alexandras Avenue, 11521 Athens, Greece"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,9,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"566","DOI":"10.3201\/eid1904.111799","article-title":"Description and Nomenclature of Neisseria meningitidis Capsule Locus","volume":"19","author":"Harrison","year":"2013","journal-title":"Emerg. 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Antimicrob Chemother."}],"container-title":["Microorganisms"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2076-2607\/13\/9\/2071\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T18:40:15Z","timestamp":1760035215000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2076-2607\/13\/9\/2071"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,9,5]]},"references-count":41,"journal-issue":{"issue":"9","published-online":{"date-parts":[[2025,9]]}},"alternative-id":["microorganisms13092071"],"URL":"https:\/\/doi.org\/10.3390\/microorganisms13092071","relation":{},"ISSN":["2076-2607"],"issn-type":[{"value":"2076-2607","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,9,5]]}}}