Три фактора успешной интерпретации ПЦР при внебольничной пневмонии у детей: выбор образца, пороговый цикл и биомаркеры

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.

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.

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.

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 < 25 при микоплазменной инфекции служит независимым предиктором тяжелого течения и требует госпитализации. Для респираторно-синцитиального вируса (РСВ) порог Ct < 25 ассоциирован с тяжелым течением (скорректированное отношение шансов, aOR 2,26), для метапневмовируса человека (hMPV) – Ct < 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.

Заключение. Успех ПЦР-диагностики ВП у детей определяется тремя факторами: правильным выбором образца, корректной интерпретацией Ct и интеграцией с биомаркерами.

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