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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">avk</journal-id><journal-title-group><journal-title xml:lang="ru">Архивъ внутренней медицины</journal-title><trans-title-group xml:lang="en"><trans-title>The Russian Archives of Internal Medicine</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2226-6704</issn><issn pub-type="epub">2411-6564</issn><publisher><publisher-name>“SINAPS” LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.20514/2226-6704-2023-13-2-136-143</article-id><article-id custom-type="elpub" pub-id-type="custom">avk-1596</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>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="en"><subject>ORIGINAL ARTICLE</subject></subj-group></article-categories><title-group><article-title>Сложности верификации диагноза лихорадки Ку при отрицательных результатах ПЦР-тестирования</article-title><trans-title-group xml:lang="en"><trans-title>Difficulties of Q Fever Diagnostic Verification at Negative PCR Testing Results</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-9096-5217</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Янковская</surname><given-names>Я. Д.</given-names></name><name name-style="western" xml:lang="en"><surname>Yankovskaya</surname><given-names>Ya. D.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Янина Дмитриевна Янковская</p><p>Кафедра инфекционных болезней и эпидемиологии лечебного факультета</p><p>Лаборатория эпидемиологии природно-очаговых инфекций</p><p>Москва</p></bio><bio xml:lang="en"><p>Yanina D. Yankovskaya</p><p>Department of Infectious Diseases and Epidemiology of the Medical Faculty</p><p>Laboratory for Epidemiology of Natural Focal Infections</p><p>Moscow</p></bio><email xlink:type="simple">yankowskaya@gmail.com</email><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0003-2532-0054</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Чеканова</surname><given-names>Т. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Chekanova</surname><given-names>T. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Лаборатория эпидемиологии природно-очаговых инфекций</p><p>Москва</p></bio><bio xml:lang="en"><p>Laboratory for Epidemiology of Natural Focal Infections</p><p>Moscow</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Кутателадзе</surname><given-names>М. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Kutateladze</surname><given-names>M. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кафедра инфекционных болезней и эпидемиологии лечебного факультета</p><p>Москва</p></bio><bio xml:lang="en"><p>Department of Infectious Diseases and Epidemiology of the Medical Faculty</p><p>Moscow</p></bio><xref ref-type="aff" rid="aff-3"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8330-336X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Петремгвдлишвили</surname><given-names>К.</given-names></name><name name-style="western" xml:lang="en"><surname>Petremgvdlishvili</surname><given-names>K.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Лаборатория эпидемиологии природно-очаговых инфекций</p><p>Москва</p></bio><bio xml:lang="en"><p>Laboratory for Epidemiology of Natural Focal Infections</p><p>Moscow</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Чернобровкина</surname><given-names>Т. Я.</given-names></name><name name-style="western" xml:lang="en"><surname>Chernobrovkina</surname><given-names>T. Ya.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Кафедра инфекционных болезней и эпидемиологии лечебного факультета</p><p>Москва</p></bio><bio xml:lang="en"><p>Department of Infectious Diseases and Epidemiology of the Medical Faculty</p><p>Moscow</p></bio><xref ref-type="aff" rid="aff-3"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>Федеральное государственное автономное образовательное учреждение высшего образования «Российский Национальный Исследовательский Медицинский Университет им. Н.И. Пирогова» Минздрава России; Федеральное бюджетное учреждение науки «Центральный научно-исследовательский институт эпидемиологии» Роспотребнадзора</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Russian National Research Medical University named after. N.I. Pirogov; Central Research Institute of Epidemiology</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>Федеральное бюджетное учреждение науки «Центральный научно-исследовательский институт эпидемиологии» Роспотребнадзора</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Central Research Institute of Epidemiology</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-3"><aff xml:lang="ru"><institution>Федеральное государственное автономное образовательное учреждение высшего образования «Российский Национальный Исследовательский Медицинский Университет им. Н.И. Пирогова» Минздрава России</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Russian National Research Medical University named after. N.I. Pirogov</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>05</day><month>04</month><year>2023</year></pub-date><volume>13</volume><issue>2</issue><fpage>136</fpage><lpage>143</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Янковская Я.Д., Чеканова Т.А., Кутателадзе М.В., Петремгвдлишвили К., Чернобровкина Т.Я., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Янковская Я.Д., Чеканова Т.А., Кутателадзе М.В., Петремгвдлишвили К., Чернобровкина Т.Я.</copyright-holder><copyright-holder xml:lang="en">Yankovskaya Y.D., Chekanova T.A., Kutateladze M.V., Petremgvdlishvili K., Chernobrovkina T.Y.</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://www.medarhive.ru/jour/article/view/1596">https://www.medarhive.ru/jour/article/view/1596</self-uri><abstract><p>Цель работы: продемонстрировать сложность верификации диагноза лихорадки Ку при отрицательных результатах ПЦР-тестирования на наличие в крови ДНК Coxiella burnetii и оценить встречаемость серологических маркеров среди пациентов, отобранных для настоящего исследования по совокупности клинико-эпидемиологических данных. Материалы и методы: у 111 пациентов методами иммуноферментного анализа и полимеразно-цепной реакции изучены образцы плазмы/сыворотки крови на наличие специфических антител и ДНК возбудителя. При выявлении антител к C. burnetii II фазы дополнительно проводились исследования на наличие IgG/IgA к коксиеллам I фазы, а также была изучена авидность специфических иммуноглобулинов класса G. Результаты: у 10 пациентов с отрицательными результатами полимеразно-цепной реакции были выявлены антитела к C. burnetii. В статье приведено подробное описание трех клинических случаев с лабораторным подтверждением инфицирования C. Burnetii на основании анализа полученных серологических профилей, титров специфических антител и оценки их авидности. Заключение: результаты исследования свидетельствуют о том, что отрицательные результаты ПЦР-тестирования не исключают у пациентов инфицирования C. Burnetii. В связи с этим, пациентам, у которых по клинико-эпидемиологическим данным не исключается лихорадка Ку, целесообразно назначение комплекса лабораторных исследований для верификации диагноза, предусматривающего не только исследования ДНК возбудителя, но и специфических антител. Для уточнения стадии заболевания и снижения риска развития осложнений коксиеллеза необходим мониторинг динамики титров антител к C. burnetii в I и II фазовых состояниях дифференциально. Оценка авидности антител будет полезна для понимания срока давности инфицирования C. burnetii.</p></abstract><trans-abstract xml:lang="en"><p>Aim of the work: to demonstrate the difficulty of verifying the diagnosis of Q fever with negative results of PCR (DNA of Coxiella burnetii) in the blood and to assess the occurrence of serological markers among patients selected for this study based on a combination of clinical and epidemiological data. Materials and methods: plasma/serum samples of 111 patients according to clinical and epidemiological data studied due ELISA and PCR for specific antibodies to Coxiella burnetii and DNA of pathogen. Additionally, in the presence IgG to C. burnetii phase II, IgG / IgA to phase I and the avidity of specific IgG were studied. Results: the specific antibodies to C. burnetii antigens at negative results of PCR detected in 10 cases. The article provides the description of three clinical cases for demonstration of difficulties of coxiellosis diagnosis with analysis of serological profiles, titers and avidity of antibodies. Conclusion: the results of the study indicate that negative results of PCR testing do not exclude C. burnetii infection. For patients who, according to clinical and epidemiological data, Q fever is not excluded, it is advisable to prescribe a complex of laboratory tests to verify the diagnosis, which includes not only studies of the pathogen’s DNA, but also specific antibodies. To clarify the stage of the disease and reduce the risk of developing complications of coxiellosis, it is necessary to monitor the dynamics of antibody titers to C. burnetii in phase I and II phase states differentially.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>лихорадка Ку</kwd><kwd>коксиеллез</kwd><kwd>антитела к Coxiella burnetiid</kwd></kwd-group><kwd-group xml:lang="en"><kwd>Q fever</kwd><kwd>coxiellosis</kwd><kwd>antibodies to Coxiella burnetii</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">Salifu SP, Bukari ARA, Frangoulidis D, et al. 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