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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="en"><front><journal-meta><journal-id journal-id-type="publisher-id">nnp</journal-id><journal-title-group><journal-title xml:lang="en">Neurology, Neuropsychiatry, Psychosomatics</journal-title><trans-title-group xml:lang="ru"><trans-title>Неврология, нейропсихиатрия, психосоматика</trans-title></trans-title-group></journal-title-group><issn pub-type="ppub">2074-2711</issn><issn pub-type="epub">2310-1342</issn><publisher><publisher-name>"IMA-Press", LLC</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="doi">10.14412/20742711-2023-6-101-108</article-id><article-id custom-type="elpub" pub-id-type="custom">nnp-2145</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="en"><subject>CLINICAL OBSERVATIONS</subject></subj-group><subj-group subj-group-type="section-heading" xml:lang="ru"><subject>КЛИНИЧЕСКИЕ НАБЛЮДЕНИЯ</subject></subj-group></article-categories><title-group><article-title>A case of chorea with cognitive impairment associated with polycythemia vera</article-title><trans-title-group xml:lang="ru"><trans-title>Клинический случай хореи с когнитивными нарушениями на фоне истинной полицитемии</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0001-7214-583X</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Шпилюкова</surname><given-names>Ю. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Shpilyukova</surname><given-names>Yu. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>Юлия Александровна Шпилюкова</p><p>125367, Москва, Волоколамское шоссе, 80</p></bio><bio xml:lang="en"><p>Yulia Alexandrovna Shpilyukova</p><p>80, Volokolamskoe Shosse, Moscow 125367</p></bio><email xlink:type="simple">jshpilyukova@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/0000-0003-3141-0267</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Сметанина</surname><given-names>О. В.</given-names></name><name name-style="western" xml:lang="en"><surname>Smetanina</surname><given-names>O. V.</given-names></name></name-alternatives><bio xml:lang="ru"><p>125367, Москва, Волоколамское шоссе, 80</p></bio><bio xml:lang="en"><p>80, Volokolamskoe Shosse, Moscow 125367</p></bio><xref ref-type="aff" rid="aff-1"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0009-0009-8324-2278</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Колпина</surname><given-names>А. А.</given-names></name><name name-style="western" xml:lang="en"><surname>Kolpina</surname><given-names>A. A.</given-names></name></name-alternatives><bio xml:lang="ru"><p>123112, Москва, Пресненская набережная, 8, стр. 1</p></bio><bio xml:lang="en"><p>8, Presnenskaya Emb., Build. 1, Moscow 123112</p></bio><xref ref-type="aff" rid="aff-2"/></contrib><contrib contrib-type="author" corresp="yes"><contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-2704-6282</contrib-id><name-alternatives><name name-style="eastern" xml:lang="ru"><surname>Иллариошкин</surname><given-names>С. Н.</given-names></name><name name-style="western" xml:lang="en"><surname>Illarioshkin</surname><given-names>S. N.</given-names></name></name-alternatives><bio xml:lang="ru"><p>125367, Москва, Волоколамское шоссе, 80</p></bio><bio xml:lang="en"><p>80, Volokolamskoe Shosse, Moscow 125367</p></bio><xref ref-type="aff" rid="aff-1"/></contrib></contrib-group><aff-alternatives id="aff-1"><aff xml:lang="ru"><institution>ФГБНУ «Научный центр неврологии»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>Research Centre of Neurology</institution><country>Russian Federation</country></aff></aff-alternatives><aff-alternatives id="aff-2"><aff xml:lang="ru"><institution>ООО «Клиники Чайка»</institution><country>Россия</country></aff><aff xml:lang="en"><institution>“Сhaika Clinics” LLC</institution><country>Russian Federation</country></aff></aff-alternatives><pub-date pub-type="collection"><year>2023</year></pub-date><pub-date pub-type="epub"><day>17</day><month>12</month><year>2023</year></pub-date><volume>15</volume><issue>6</issue><fpage>101</fpage><lpage>108</lpage><permissions><copyright-statement>Copyright &amp;#x00A9; Shpilyukova Y.A., Smetanina O.V., Kolpina A.A., Illarioshkin S.N., 2023</copyright-statement><copyright-year>2023</copyright-year><copyright-holder xml:lang="ru">Шпилюкова Ю.А., Сметанина О.В., Колпина А.А., Иллариошкин С.Н.</copyright-holder><copyright-holder xml:lang="en">Shpilyukova Y.A., Smetanina O.V., Kolpina A.A., Illarioshkin S.N.</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://nnp.ima-press.net/nnp/article/view/2145">https://nnp.ima-press.net/nnp/article/view/2145</self-uri><abstract><p>Polycythemia vera (PV) is a clonal myeloproliferative disorder that is often associated with neurological symptoms. Rare manifestations of PV may include movement disorders (mainly chorea) and cognitive impairment (CI), which are fully or partially reversible with appropriate treatment. We present a case of chorea with CI in a 69-year-old man with a confirmed с1849G&gt;T (V617F) mutation in the JAK2 gene with no vascular pathology on neuroimaging. In this patient, there is a clear correlation between the regression of the movement disorders with therapeutic phlebotomy and the start of treatment with hydroxyurea, which allows the conclusion that chorea has the secondary form. The cognitive symptoms remained at the same level after the start of treatment and during the one-year follow-up and did not develop further. In view of the patient's age, a concomitant neurodegenerative disease cannot be ruled out. In elderly patients with new-onset chorea and CI, it is therefore important to consider PV as a possible cause of these disorders, as early diagnosis of this condition allows timely initiation of effective treatment and prevention of the development of complications.</p></abstract><trans-abstract xml:lang="ru"><p>Истинная полицитемия (ИП) – клональное миелопролиферативное заболевание, часто сопровождающееся неврологическими симптомами. Редкими проявлениями ИП могут быть двигательные расстройства (в первую очередь хорея) и когнитивные нарушения (КН), которые являются полностью или частично обратимыми при назначении правильного лечения. Мы представляем случай хореи с КН у мужчины 69 лет с подтвержденной мутацией с1849G&gt;T (V617F) в гене JAK2 и отсутствием сосудистой патологии по данным нейровизуализации. У пациента отмечается четкая взаимосвязь регресса двигательных расстройств с проведением лечебных кровопусканий и началом приема гидроксимочевины, что позволяет сделать вывод о вторичной форме хореи. Когнитивные симптомы после начала лечения и в течение года наблюдения оставались на прежнем уровне и не прогрессировали. Учитывая возраст больного, нельзя также исключить сопутствующее нейродегенеративное заболевание. Таким образом, у пожилых пациентов с впервые развившейся хореей и КН важно рассматривать ИП как возможную причину данных нарушений, поскольку ранняя диагностика этого состояния позволяет вовремя начать эффективное лечение и предотвратить развитие осложнений.</p></trans-abstract><kwd-group xml:lang="ru"><kwd>истинная полицитемия</kwd><kwd>хорея</kwd><kwd>когнитивные нарушения</kwd><kwd>диагностика</kwd></kwd-group><kwd-group xml:lang="en"><kwd>polycythemia vera</kwd><kwd>chorea</kwd><kwd>cognitive impairment</kwd><kwd>diagnosis</kwd></kwd-group><funding-group><funding-statement xml:lang="ru">Исследование не имело спонсорской поддержки</funding-statement><funding-statement xml:lang="en">The investigation has not been sponsored</funding-statement></funding-group></article-meta></front><back><ref-list><title>References</title><ref id="cit1"><label>1</label><citation-alternatives><mixed-citation xml:lang="ru">Селиверстов ЮА, Клюшников СА. Дифференциальная диагностика хореи. 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