Russian Journal of Infection and ImmunityRussian Journal of Infection and ImmunityИнфекция и иммунитет2220-76192313-7398SPb RAACI1778510.15789/2220-7619-MCO-17785ORIGINAL ARTICLESОРИГИНАЛЬНЫЕ СТАТЬИResearch ArticleMolecular characterization of pga gene types A–D among multi-drug resistant strains of Acinetobacter baumanniiМолекулярная характеристика генов pga типа A–D среди полирезистентных штаммов Acinetobacter baumanniiSupreetaM. S.СупритаМ. С.
India

BDS Student, Department of Microbiology, Saveetha Dental College and Hospitals

бакалавр стоматологической хирургии, кафедра микробиологии, стоматологический колледж и больница Савита

152201022.sdc@saveetha.comKannika ParameshwariK.Канника ПарамешварК.
India

PhD Student, Department of Microbiology, Saveetha Dental College and Hospitals

аспирант, кафедра микробиологии, стоматологический колледж и больницы Савита

kannikakannan03@gmail.comSmiline GirijaA.S.Смилине ГириджаА. С.
India

Professor, Department of Microbiology, Saveetha Dental College and Hospitals

профессор кафедры микробиологии, стоматологический колледж и больница Савита

smilinejames25@gmail.comVijayashree PriyadharsiniJ.Виджаяшри ПриядхарсиниДж.
India

Associate Professor, Department of Microbiology, Saveetha Dental College and Hospitals

доцент кафедры микробиологии, стоматологический колледж и больница Савита

vijipriya26@gmail.comSaveetha Institute of Medical and Technical SciencesИнститут медицинских и технических наук Савита03062025150920251535365422709202405052025Copyright ©; 2025, Supreeta M., Kannika Parameshwari K., Smiline Girija A., Vijayashree Priyadharsini J.Copyright ©; 2025, Суприта М., Канника Парамешвар К., Смилине Гириджа А., Виджаяшри Приядхарсини Д.2025Supreeta M., Kannika Parameshwari K., Smiline Girija A., Vijayashree Priyadharsini J.Суприта М., Канника Парамешвар К., Смилине Гириджа А., Виджаяшри Приядхарсини Д.https://creativecommons.org/licenses/by/4.0https://iimmun.ru/iimm/article/view/17785

This study aimed to explore the prevalence of Acinetobacter baumannii in clinical settings, its antimicrobial resistance, and biofilm formation ability in ventilator-associated pneumonia (VAP) patients, with a particular focus on the pgaABCD gene locus responsible for biofilm formation. A total of 53 isolates were collected over a 5-month period from patients suffering from pneumonia and lower respiratory tract infections. The isolates were identified, and their drug resistance profiles were evaluated using the VITEK automated system. Biofilm formation ability was assessed using the crystal violet assay. The presence of the pgaABCD gene was confirmed through PCR, and the sequences were analyzed to investigate gene prevalence and mutations. Among the 53 clinical samples, 29 isolates (54.7%) were confirmed as A. baumannii. Biofilm formation was detected in 62.1% of the isolates, with varying levels of biofilm production. All 29 isolates (100%) encoded both the pgaA and pgaD genes, while the pgaB and pgaC genes were present in 93.10% and 89.66% of the isolates, respectively. Multidrug-resistant (MDR) strains were prevalent among the clinical isolates, with high biofilm production ability. Sequencing of the pgaABCD genes revealed mutations contributing to the diversity of biofilm formation. This study emphasizes the strong relationship between the pgaABCD locus and biofilm formation in MDR A. baumannii strains. The high prevalence of biofilm-forming isolates underscores the challenges in treating infections caused by A. baumannii, especially in VAP patients. These findings highlight the need for biofilm-targeted treatment strategies to improve patient outcomes in healthcare settings.

Целью настоящего исследования было изучение в клинических условиях распространенности Acinetobacter baumannii, его устойчивости к противомикробным препаратам и способности к образованию биопленки у пациентов с ИВЛ-ассоциированной пневмонией (ИАП), основанное на исследовании локуса гена pgaABCD, ответственного за образование биопленки. Всего за 5 месяцев было собрано 53 изолята от пациентов, страдающих пневмонией и инфекциями нижних дыхательных путей. Изоляты были идентифицированы, а их профили лекарственной устойчивости были оценены с помощью автоматизированной системы VITEK. Способность к образованию биопленки была оценена с помощью теста с кристаллическим фиолетовым. Наличие гена pgaABCD было подтверждено с помощью ПЦР, а последовательности гена были проанализированы для оценки его распространенности и мутаций. Среди 53 клинических образцов в 29 изолятах (54,7%) было подтверждено наличие A. baumannii. Образование биопленки разной выраженности было обнаружено в 62,1% изолятах. Все 29 изолятов (100%) A. baumannii кодировали как гены pgaA, так и pgaD, тогда как гены pgaB и pgaC обнаружены в 93,10 и 89,66% изолятов соответственно. Среди клинических изолятов преобладали штаммы с множественной лекарственной устойчивостью (МЛУ) с высокой способностью к образованию биопленки. Секвенирование генов pgaABCD выявило мутации, способствующие различным типам образования биопленки. Настоящее исследование подчеркивает тесную связь между локусом pgaABCD и образованием биопленки в штаммах A. baumannii с МЛУ. Высокая распространенность изолятов, образующих биопленку, подчеркивает трудности в лечении инфекций, вызванных A. baumannii, особенно у пациентов с ИАП. Полученные результаты подчеркивают необходимость разработки стратегий терапии, воздействующей на биопленку, для улучшения результатов лечения пациентов в медицинских учреждениях.

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