{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,18]],"date-time":"2026-09-18T00:53:24Z","timestamp":1789692804655,"version":"4.0.1"},"reference-count":37,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2022,3,31]],"date-time":"2022-03-31T00:00:00Z","timestamp":1648684800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Background and objectives: Staphylococcus aureus (S. aureus) is often recovered from the pharynx. However, the role of this pathogen in the etiology of tonsillar inflammation is still unclear and complicated due to frequent carriage of S. aureus. The aim of the study was to evaluate the frequency and the clinical importance of S. aureus colonization and biofilm production ability in patients with recurrent tonsillitis (RT) using patient samples from tonsillar crypts during tonsillectomy, and from the throat, nasal cavity, and armpits after tonsillectomy. Materials and Methods: A case series study was carried out at a tertiary referral center among 16 patients diagnosed with RT who were undergoing tonsillectomy. Samples from tonsillar crypts were obtained during tonsillectomy, and samples from the throat, nasal cavity, and armpit were obtained a year after surgery. An evaluation of S. aureus incidence, biofilm formation, and antibacterial susceptibility was performed. Results: During tonsillectomy, 16 strains of S. aureus were isolated from 16 patients, while 15\/16 S. aureus strains were biofilm producers. A year after tonsillectomy, 8 S. aureus strains were isolated from 6 out of 16 patients, while 6\/8 S. aureus strains were biofilm producers. After tonsillectomy, 3 patients showed S. aureus in throat culture. Conclusions: In 10\/16 cases S. aureus was the causative agent of RT, in 4\/16 cases patients had a predisposition to colonization of S. aureus, and in 2\/16 cases S. aureus was a part of the patients` oral microbiome. Tonsillectomy results in less frequent isolation of S. aureus strains.<\/jats:p>","DOI":"10.3390\/pathogens11040427","type":"journal-article","created":{"date-parts":[[2022,3,31]],"date-time":"2022-03-31T21:34:29Z","timestamp":1648762469000},"page":"427","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Evaluation of Staphylococcus aureus Colonization in Adult Patients Undergoing Tonsillectomy for Recurrent Tonsillitis"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9855-5546","authenticated-orcid":false,"given":"Renata","family":"Klagisa","sequence":"first","affiliation":[{"name":"Department of Otorhinolaryngology, Daugavpils Regional Hospital, LV-5401 Daugavpils, Latvia"},{"name":"Department of Doctoral Studies, Riga Stradins University, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7123-4048","authenticated-orcid":false,"given":"Karlis","family":"Racenis","sequence":"additional","affiliation":[{"name":"Department of Biology and Microbiology, Riga Stradins University, LV-1007 Riga, Latvia"},{"name":"Center of Nephrology, Pauls Stradins Clinical University Hospital, LV-1002 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Renars","family":"Broks","sequence":"additional","affiliation":[{"name":"Department of Biology and Microbiology, Riga Stradins University, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ligija","family":"Kise","sequence":"additional","affiliation":[{"name":"Department of Doctoral Studies, Riga Stradins University, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0805-7063","authenticated-orcid":false,"given":"Juta","family":"Kroi\u010da","sequence":"additional","affiliation":[{"name":"Department of Biology and Microbiology, Riga Stradins University, LV-1007 Riga, Latvia"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2022,3,31]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"475","DOI":"10.1086\/520016","article-title":"Throat Swabs Are Necessary to Reliably Detect Carriers of Staphylococcus aureus","volume":"45","author":"Mertz","year":"2007","journal-title":"Clin. 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