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<article article-type="research-article" dtd-version="1.3" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xml:lang="ru"><front><journal-meta><journal-id journal-id-type="publisher-id">pediatricjournal</journal-id><journal-title-group><journal-title xml:lang="ru">Архив педиатрии и детской хирургии</journal-title><trans-title-group xml:lang="en"><trans-title>Archives of Pediatrics and Pediatric Surgery</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2949-4664</issn><issn pub-type="epub">3033-6783</issn><publisher><publisher-name>НИКИ детства Минздрава Московской области</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.66825/2949-4664-apps-4-1-85-101</article-id><article-id custom-type="elpub" pub-id-type="custom">pediatricjournal-267</article-id><article-categories><subj-group subj-group-type="heading"><subject>Research Article</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>ОБЗОРЫ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>REVIEWS</subject></subj-group></article-categories><title-group><article-title>Три фактора успешной интерпретации ПЦР при внебольничной пневмонии у детей: выбор образца, пороговый цикл и биомаркеры</article-title><trans-title-group xml:lang="en"><trans-title>Three factors for successful interpretation of PCR in community-acquired pneumonia in children: specimen selection, cycle threshold, and biomarkers</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Медведева</surname><given-names>Л. С.</given-names></name><name name-style="western" xml:lang="en"><surname>Medvedeva</surname><given-names>L. S.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Медведева Лидия Сергеевна, ординатор кафедры поликлинической педиатрии</p><p>620028, г. Екатеринбург, ул. Репина, д. 3</p></bio><bio xml:lang="en"><p>Lidia S. Medvedeva, Resident in Pediatrics of Department of Outpatient Pediatrics</p><p>3 Repina str., Yekaterinburg, 620028</p></bio><email xlink:type="simple">lidiia.medvedeva@yandex.ru</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-4588-5909</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Царькова</surname><given-names>С. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Tsarkova</surname><given-names>S. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Царькова Софья Анатольевна, д.м.н., заведующая кафедрой поликлинической педиатрии</p><p>620028, г. Екатеринбург, ул. Репина, д. 3</p></bio><bio xml:lang="en"><p>Sofia A. Tsarkova, Dr. Sci. (Med.), Head of the Department of Outpatient Pediatrics</p><p>3 Repina str., Yekaterinburg, 620028</p></bio><email xlink:type="simple">tsarkova_ugma@bk.ru</email><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Уральский государственный медицинский университет Министерства здравоохранения Российской Федерации</institution></aff><aff xml:lang="en"><institution>Ural State Medical University</institution></aff></aff-alternatives><pub-date pub-type="collection"><year>2026</year></pub-date><pub-date pub-type="epub"><day>23</day><month>05</month><year>2026</year></pub-date><volume>4</volume><issue>1</issue><fpage>85</fpage><lpage>101</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Медведева Л.С., Царькова С.А., 2026</copyright-statement><copyright-year>2026</copyright-year><copyright-holder xml:lang="ru">Медведева Л.С., Царькова С.А.</copyright-holder><copyright-holder xml:lang="en">Medvedeva L.S., Tsarkova S.A.</copyright-holder><license xml:lang="ru" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>Данная работа распространяется под лицензией Creative Commons Attribution 4.0.</license-p></license><license xml:lang="en" license-type="creative-commons-attribution" xlink:href="https://creativecommons.org/licenses/by/4.0/" xlink:type="simple"><license-p>This work is licensed under a Creative Commons Attribution 4.0 License.</license-p></license></permissions><self-uri xlink:href="https://journal.nikid.ru/jour/article/view/267">https://journal.nikid.ru/jour/article/view/267</self-uri><abstract><sec><title>Введение</title><p>Введение. Внебольничная пневмония (ВП) сохраняет лидирующие позиции в структуре заболеваемости и смертности детского населения. Внедрение методов полимеразной цепной реакции (ПЦР) расширило диагностические возможности, однако актуализировало вопросы выбора респираторного образца и интерпретации результатов с учетом пороговых циклов (Ct) и бессимптомной колонизации.</p></sec><sec><title>Цель</title><p>Цель. Систематизировать современные данные о диагностической ценности различных респираторных образцов при ПЦР-диагностике ВП у детей, определить границы применимости пороговых циклов для дифференциации инфекции и колонизации, а также обосновать необходимость интеграции молекулярных методов с биомаркерами.</p></sec><sec><title>Методы</title><p>Методы. Проведен систематический поиск литературы в базах PubMed, Scopus, Web of Science, Google Scholar, Cochrane Library и eLibrary (2000–2026 гг.). Всего отобрано 83 исследования для итогового анализа.</p></sec><sec><title>Результаты</title><p>Результаты. Идентифицированы три ключевых фактора успешной интерпретации ПЦР-диагностики: выбор образца, интерпретация Ct и интеграция с биомаркерами. Показано, что диагностическая ценность назофарингеальных (НФ) мазков для верификации пневмококковой этиологии ВП стремится к нулю вследствие высокой частоты колонизации (40–60%), что делает стерильные локусы единственным надежным источником. В противоположность этому для Mycoplasma pneumoniae оптимальными являются орофарингеальные мазки (чувствительность 96,2%), а слюна демонстрирует сопоставимые результаты. Для Российской Федерации критически важно выявление 36–41% макролид-резистентных штаммов M. pneumoniae с региональными различиями; 62% случаев сопровождаются вирусной коинфекцией (парагрипп 28%, SARS-CoV-2 19%, РСВ 12%). Порог Ct &lt; 25 при микоплазменной инфекции служит независимым предиктором тяжелого течения и требует госпитализации. Для респираторно-синцитиального вируса (РСВ) порог Ct &lt; 25 ассоциирован с тяжелым течением (скорректированное отношение шансов, aOR 2,26), для метапневмовируса человека (hMPV) – Ct &lt; 27 (aOR 4,32). Прокальцитонин-ориентированные протоколы позволяют сократить необоснованное назначение антибиотиков, однако гетерогенность педиатрических данных диктует необходимость применения мультимаркерных подходов, включающих гепарин-связывающий белок (HBP), чувствительность которого составляет 82%, специфичность 86%, а комбинация с прокальцитонином повышает площадь под кривой (AUC) до 0,94.</p></sec><sec><title>Заключение</title><p>Заключение. Успех ПЦР-диагностики ВП у детей определяется тремя факторами: правильным выбором образца, корректной интерпретацией Ct и интеграцией с биомаркерами.</p></sec></abstract><trans-abstract xml:lang="en"><sec><title>Introduction</title><p>Introduction. Community-acquired pneumonia (CAP) maintains a leading position in the morbidity and mortality structure of the pediatric population. The introduction of polymerase chain reaction (PCR) methods has expanded diagnostic capabilities; however, it has also brought to the forefront issues regarding the choice of respiratory specimen and the interpretation of results, considering cycle threshold (Ct) values and asymptomatic colonization.</p></sec><sec><title>Objective</title><p>Objective. To systematize current data on the diagnostic value of various respiratory specimens in PCR diagnostics of CAP in children, to define the applicability limits of cycle thresholds for differentiating infection from colonization, and to justify the necessity of integrating molecular methods with biomarkers.</p></sec><sec><title>Methods</title><p>Methods. A systematic literature search was conducted in the PubMed, Scopus, Web of Science, Google Scholar, Cochrane Library and eLibrary databases (2000–2026). A total of 83 studies were selected for the final analysis.</p></sec><sec><title>Results</title><p>Results. Three key factors for the successful interpretation of PCR diagnostics were identified: specimen selection, Ct interpretation, and integration with biomarkers. It is shown that the diagnostic value of nasopharyngeal (NP) swabs for verifying pneumococcal etiology of CAP approaches zero due to the high frequency of colonization (40–60%), making sterile loci the only reliable source. In contrast, for Mycoplasma pneumoniae, oropharyngeal swabs are optimal (sensitivity 96.2%), while saliva demonstrates comparable results. Critically important for the Russian Federation is the identification of 36–41% macrolide-resistant M. pneumoniae strains with regional variations; 62% of cases are accompanied by viral coinfection (parainfluenza 28%, SARS-CoV-2 19%, RSV 12%). A Ct value &lt; 25 in Mycoplasma infection serves as an independent predictor of severe disease and necessitates hospitalization. For respiratory syncytial virus (RSV), Ct &lt; 25 is associated with severe disease (adjusted odds ratio, aOR 2.26); for human metapneumovirus (hMPV), Ct &lt; 27 (aOR 4.32). Procalcitonin-guided protocols can reduce inappropriate antibiotic prescriptions; however, the heterogeneity of pediatric data dictates the need for multi-marker approaches, including heparin-binding protein (HBP), with sensitivity 82%, specificity 86%, and its combination with procalcitonin increasing the area under the curve (AUC) to 0.94.</p></sec><sec><title>Conclusion</title><p>Conclusion. The success of PCR diagnostics for CAP in children is determined by three factors: appropriate specimen selection, correct interpretation of Ct values, and integration with biomarkers.</p></sec></trans-abstract><kwd-group xml:lang="ru"><kwd>внебольничная пневмония</kwd><kwd>дети</kwd><kwd>педиатрия</kwd><kwd>ПЦР-диагностика</kwd><kwd>респираторные образцы</kwd><kwd>орофарингеальные мазки</kwd><kwd>пороговый цикл</kwd><kwd>прокальцитонин</kwd><kwd>колонизация</kwd><kwd>биомаркеры</kwd></kwd-group><kwd-group xml:lang="en"><kwd>community-acquired pneumonia</kwd><kwd>children</kwd><kwd>pediatrics</kwd><kwd>PCR diagnostics</kwd><kwd>respiratory samples</kwd><kwd>oropharyngeal swabs</kwd><kwd>cycle threshold</kwd><kwd>procalcitonin</kwd><kwd>colonization</kwd><kwd>biomarkers</kwd></kwd-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">McAllister DA, Liu L, Shi T, et al. 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