<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE root>
<article 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" xmlns:ali="http://www.niso.org/schemas/ali/1.0/" article-type="research-article" dtd-version="1.2" xml:lang="en"><front><journal-meta><journal-id journal-id-type="publisher-id">Russian Journal of Infection and Immunity</journal-id><journal-title-group><journal-title xml:lang="en">Russian Journal of Infection and Immunity</journal-title><trans-title-group xml:lang="ru"><trans-title>Инфекция и иммунитет</trans-title></trans-title-group></journal-title-group><issn publication-format="print">2220-7619</issn><issn publication-format="electronic">2313-7398</issn><publisher><publisher-name xml:lang="en">SPb RAACI</publisher-name></publisher></journal-meta><article-meta><article-id pub-id-type="publisher-id">1765</article-id><article-id pub-id-type="doi">10.15789/2220-7619-AAB-1765</article-id><article-categories><subj-group subj-group-type="toc-heading" xml:lang="en"><subject>ORIGINAL ARTICLES</subject></subj-group><subj-group subj-group-type="toc-heading" xml:lang="ru"><subject>ОРИГИНАЛЬНЫЕ СТАТЬИ</subject></subj-group><subj-group subj-group-type="article-type"><subject>Research Article</subject></subj-group></article-categories><title-group><article-title xml:lang="en">An association between low vitamin D status and childhood pneumonia severity in hospitalized bulgarian patients</article-title><trans-title-group xml:lang="ru"><trans-title>Связь дефицита витамина D с тяжестью пневмонии у госпитализированных детей в Болгарии</trans-title></trans-title-group></title-group><contrib-group><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Rimpova</surname><given-names>N.</given-names></name><name xml:lang="ru"><surname>Римпова</surname><given-names>Н.</given-names></name></name-alternatives><address><country country="BG">Bulgaria</country></address><bio xml:lang="en"><p>MD, Assistant Professor, Department of Paediatrics</p></bio><bio xml:lang="ru"><p>ассистент кафедры педиатрии</p></bio><email>nadiarimpova@abv.bg</email><xref ref-type="aff" rid="aff1"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Valcheva</surname><given-names>V.</given-names></name><name xml:lang="ru"><surname>Вылчева</surname><given-names>В.</given-names></name></name-alternatives><address><country country="BG">Bulgaria</country></address><bio xml:lang="en"><p>PhD, Associate Professor, Department of Infectious Microbiology</p></bio><bio xml:lang="ru"><p>к.н., доцент кафедры инфекционной микробиологии</p></bio><email>violeta_valcheva@mail.bg</email><xref ref-type="aff" rid="aff2"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Tsakova</surname><given-names>A.</given-names></name><name xml:lang="ru"><surname>Цакова</surname><given-names>А.</given-names></name></name-alternatives><address><country country="BG">Bulgaria</country></address><bio xml:lang="en"><p>Head Assistant Professor, Central Clinical Laboratory</p></bio><bio xml:lang="ru"><p>ведущий ассистент центральной клинической лаборатории</p></bio><email>adelina_d@abv.bg</email><xref ref-type="aff" rid="aff3"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Shivachev</surname><given-names>H.</given-names></name><name xml:lang="ru"><surname>Шивачев</surname><given-names>Х.</given-names></name></name-alternatives><address><country country="BG">Bulgaria</country></address><bio xml:lang="en"><p>PhD, Associate Professor</p></bio><bio xml:lang="ru"><p>к.н., доцент, клиника детской хирургии</p></bio><email>hshivachev@gmail.com</email><xref ref-type="aff" rid="aff4"/></contrib><contrib contrib-type="author"><name-alternatives><name xml:lang="en"><surname>Iliev</surname><given-names>D.</given-names></name><name xml:lang="ru"><surname>Илиев</surname><given-names>Д.</given-names></name></name-alternatives><address><country country="BG">Bulgaria</country></address><bio xml:lang="en"><p>PhD, Associate Professor, Department of Paediatrics</p></bio><bio xml:lang="ru"><p>к.н., доцент кафедры педиатрии</p></bio><email>daniel_iliev@gmx.net</email><xref ref-type="aff" rid="aff1"/></contrib></contrib-group><aff-alternatives id="aff1"><aff><institution xml:lang="en">Children’s Hospital of the Medical University of Sofia</institution></aff><aff><institution xml:lang="ru">Детская больница Медицинского университета Софии</institution></aff></aff-alternatives><aff-alternatives id="aff2"><aff><institution xml:lang="en">Stephan Angeloff Institute of Microbiology of the Bulgarian Academy of Sciences</institution></aff><aff><institution xml:lang="ru">Институт микробиологии им. Стефана Ангелова Болгарской академии наук</institution></aff></aff-alternatives><aff-alternatives id="aff3"><aff><institution xml:lang="en">Aleksandrovska Hospital of the Medical University of Sofia</institution></aff><aff><institution xml:lang="ru">Александровская больница Софийского медицинского университета</institution></aff></aff-alternatives><aff-alternatives id="aff4"><aff><institution xml:lang="en">N.I. Pirogov University Hospital for Emergency Medicine</institution></aff><aff><institution xml:lang="ru">Университетская больница неотложной медицины им. Пирогова</institution></aff></aff-alternatives><pub-date date-type="preprint" iso-8601-date="2022-04-12" publication-format="electronic"><day>12</day><month>04</month><year>2022</year></pub-date><pub-date date-type="pub" iso-8601-date="2022-05-13" publication-format="electronic"><day>13</day><month>05</month><year>2022</year></pub-date><volume>12</volume><issue>2</issue><issue-title xml:lang="en"/><issue-title xml:lang="ru"/><fpage>373</fpage><lpage>380</lpage><history><date date-type="received" iso-8601-date="2021-07-10"><day>10</day><month>07</month><year>2021</year></date><date date-type="accepted" iso-8601-date="2021-09-22"><day>22</day><month>09</month><year>2021</year></date></history><permissions><copyright-statement xml:lang="en">Copyright ©; 2022, Rimpova N., Valcheva V., Tsakova A., Shivachev H., Iliev D.</copyright-statement><copyright-statement xml:lang="ru">Copyright ©; 2022, Римпова Н., Вылчева В., Цакова А., Шивачев Х., Илиев Д.</copyright-statement><copyright-year>2022</copyright-year><copyright-holder xml:lang="en">Rimpova N., Valcheva V., Tsakova A., Shivachev H., Iliev D.</copyright-holder><copyright-holder xml:lang="ru">Римпова Н., Вылчева В., Цакова А., Шивачев Х., Илиев Д.</copyright-holder><ali:free_to_read xmlns:ali="http://www.niso.org/schemas/ali/1.0/"/><license><ali:license_ref xmlns:ali="http://www.niso.org/schemas/ali/1.0/">https://creativecommons.org/licenses/by/4.0</ali:license_ref></license></permissions><self-uri xlink:href="https://iimmun.ru/iimm/article/view/1765">https://iimmun.ru/iimm/article/view/1765</self-uri><abstract xml:lang="en"><p>Lower respiratory tract infections are among the most important causes of morbidity and mortality in the pediatric population worldwide. Despite advances in treatment and prevention, childhood pneumonia is the major reason for hospital admissions and remains a leading cause of death claiming an estimated 800 000 children’s lives in 2018. Globally, over 1.23 million children died of pneumonia before reaching their 5<sup>th</sup> birthday — the equivalent of over 3400 deaths per day worldwide. There is growing evidence that vitamin D plays an important role in the immune system by modulating both innate and adaptive immunity. Vitamin D is an additional factor in the inflammatory response regulation. Its action is mediated via the vitamin D receptor (VDR), which is present in almost all types of immune cells, including activated CD4<sup>+</sup> and CD8<sup>+</sup> cells, B cells, macrophages, neutrophils and dendritic cells. Vitamin D deficiency is associated with decreased host defenses against infections. Therefore, our aim was to investigate whether low vitamin D status was a risk factor for pneumonia complications, usage of multiple antibiotics and prolonged hospital stay among hospitalized pediatric patients with community-aquired pneumonia. Total of 200 children (102 healthy controls and 98 with severe pneumonia) from 11 days to 17 years old were included in the study. Cases with severe pneumonia were subdivided into groups with and without complications (36 and 62, respectively). Electrochemiluminescence immunoassay was used to measure the serum 25-hydroxyvitamin D levels. The control group showed lower values than the study group. Cases with complicated pneumonia had significantly lower levels whitin the range of 29.7–68.0 nmol/l, compared with 49.1–88.6 nmol/l in cases without complications. A significant negative correlation was found between vitamin D concentrations and duration of hospital stay, the number of antibiotics used for treatment, and serum levels of inflammatory markers. The low status of vitamin D is related to the severity of the disease but has not been associated with the incidence/frequency of the disease. Children with low vitamin D levels may be at higher risk of developing life-threatening complications, intensive care admissions and a higher inflammatory response.</p></abstract><trans-abstract xml:lang="ru"><p>Инфекции нижних дыхательных путей являются одной из наиболее важных причин заболеваемости и детской смертности во всем мире. Несмотря на успехи в лечении и профилактике, детская пневмония является основной причиной госпитализации и смертности. В 2018 г. она унесла примерно 800 000 жизней. Во всем мире более 1,23 млн детей умерли от пневмонии, не дожив до своего пятилетия, что эквивалентно более 3400 смертям в день. Появляется все больше свидетельств того, что витамин D играет важную роль в иммунной системе, модулируя как врожденный, так и адаптивный иммунитет. Витамин D является дополнительным фактором регуляции воспалительной реакции. Его действие опосредуется рецептором витамина D (VDR), который присутствует практически во всех типах иммунных клеток, включая активированные клетки CD4<sup>+</sup> и CD8<sup>+</sup>, В-клетки, макрофаги, нейтрофилы и дендритные клетки. Дефицит витамина D связан со снижением защиты хозяина от инфекций. Целью данного исследования был анализ низкого уровня витамина D как фактора риска осложнений пневмонии, использования нескольких антибиотиков и длительного пребывания в больнице среди госпитализированных педиатрических пациентов с внебольничной пневмонией. Всего в исследование были включены 200 детей (102 здоровых [контроль] и 98 с тяжелой пневмонией) в возрасте от 11 дней до 17 лет. Больные с тяжелой пневмонией были разделены на 2 группы: с осложнениями (36 человек) и без осложнений (62 человека). Для измерения уровней 25-гидроксивитамина D использовали электрохемилюминесцентный иммуноанализ. Контрольная группа показала более низкие значения, чем основная группа. Больные с осложненной пневмонией имели значительно более низкие уровни (в диапазоне 29,7–68,0 нмоль/л) по сравнению с больными без осложнений (в диапазоне 49,1–88,6 нмоль/л). Была обнаружена значимая отрицательная корреляция между концентрацией витамина D и продолжительностью пребывания в больнице, количеством антибиотиков, используемых для лечения, и уровнями маркеров воспаления в сыворотке крови. Низкий уровень витамина D связан с тяжестью заболевания, но не связан с заболеваемостью/частотой заболевания. Дети с низким уровнем витамина D могут подвергаться более высокому риску развития опасных для жизни осложнений, госпитализации с реанимацией и более выраженной воспалительной реакции.</p></trans-abstract><kwd-group xml:lang="en"><kwd>severe pneumonia</kwd><kwd>serum 25-hydroxyvitamin D</kwd><kwd>children</kwd><kwd>vitamin D supplementation</kwd><kwd>inflammatory markers</kwd></kwd-group><kwd-group xml:lang="ru"><kwd>тяжелая пневмония</kwd><kwd>сыворотка 25-гидроксивитамина D</kwd><kwd>дети</kwd><kwd>добавки витамина D</kwd><kwd>маркеры воспаления</kwd></kwd-group><funding-group><award-group><funding-source><institution-wrap><institution xml:lang="en">Medical University of Sofia grant</institution></institution-wrap><institution-wrap><institution xml:lang="ru">Грант Медицинского университета Софии</institution></institution-wrap></funding-source><award-id>335</award-id></award-group><funding-statement xml:lang="en">Medical University of Sofia (Grant 335/15.01.2015), Health insurance fund Doverie, Medcross outpatient care centers, University Children’s Hospital, Pediatric Surgery Clinic at the University Hospital for Emergency Medicine “Pirogov” (Sofia).</funding-statement><funding-statement xml:lang="ru">Медицинский университет, София, Болгария (грант 335/15.01.2015)</funding-statement></funding-group></article-meta></front><body></body><back><ref-list><ref id="B1"><label>1.</label><mixed-citation>De Oliveira C., Biddulph J.P., Hirani V., Schneider I.J.C. Vitamin D and inflammatory markers: cross-sectional analyses using data from the English Longitudinal Study of Ageing (ELSA). J. Nutr. Sci., 2017, vol. 6: e1. doi: 10.1017/jns.2016.37</mixed-citation></ref><ref id="B2"><label>2.</label><mixed-citation>De Smet K., Contreras R. Human antimicrobial peptides: defensins, cathelicidins and histatins. Biotechnol. Lett., 2005, vol. 27, no. 18, pp. 1337–1347. doi: 10.1007/s10529-005-0936-5</mixed-citation></ref><ref id="B3"><label>3.</label><mixed-citation>Dhungel A., Alam M. Efficacy of vitamin D in children with pneumonia: a randomized control trial study. Janaki Med. Coll. J. Med. Sci., 2016, vol. 3, no. 1, pp. 5–13. doi: 10.3126/jmcjms.v3i1.15369</mixed-citation></ref><ref id="B4"><label>4.</label><mixed-citation>Ene M.C., Tertiu O., Vrancianu O., Chifiriuc M. Vitamin D status in adult and pediatric Romanian population. Rom. Arch. Microbiol. Immunol., 2018, vol. 77, no. 3, pp. 198–212. doi: 10.1371/journal.pone.0128010</mixed-citation></ref><ref id="B5"><label>5.</label><mixed-citation>Esposito S., Lelii M. Vitamin D and respiratory tract infections in childhood. BMC Infect Dis., 2015, vol. 15: 487. doi: 10.1186/s12879-015-1196-1</mixed-citation></ref><ref id="B6"><label>6.</label><mixed-citation>Gois P.H.F., Ferreira D., Olenski S., Seguro A.C. Vitamin D and infectious diseases: simple bystander or contributing factor? Nutrients, 2017, vol. 9, no. 7: 651. doi: 10.3390/nu9070651</mixed-citation></ref><ref id="B7"><label>7.</label><mixed-citation>Grant W.B., Lahore H., McDonnell S.L., Baggerly C.A., French C.B., Aliano J.L., Bhattoa H.P. Evidence that Vitamin D supplementation could reduce risk of influenza and COVID-19 infections and deaths. Nutrients, 2020, vol. 12, no. 4: 988. doi: 10.3390/nu12040988</mixed-citation></ref><ref id="B8"><label>8.</label><mixed-citation>Holick M.F. Vitamin D deficiency. N. Engl. J. Med., 2007, vol. 357, no. 3, pp, 266–281. doi: 10.1056/NEJMra070553</mixed-citation></ref><ref id="B9"><label>9.</label><mixed-citation>Holick M.F. Vitamin D: extraskeletal health. Rheum Dis. Clin. North. Am., 2012, vol. 38, no. 1, pp. 141–160. doi: 10.1016/ j.rdc.2012.03.013</mixed-citation></ref><ref id="B10"><label>10.</label><mixed-citation>Hossein-Nezhad A., Holick M.F. Optimize dietary intake of vitamin D: an epigenetic perspective. Curr. Opin. Clin. Nutr. Metab. Care, 2012, vol. 15, no. 6, pp. 567–579. doi: 10.1097/MCO.0b013e3283594978</mixed-citation></ref><ref id="B11"><label>11.</label><mixed-citation>Inamo Y., Hasegawa M., Saito K., Hayashi R., Ishikawa T., Yoshino Y., Hashimoto K., Fuchigami T. Serum vitamin D concentrations and associated severity of acute lower respiratory tract infections in Japanese hospitalized children. Pediatr. Int., 2011, vol. 53, no. 2, pp. 199–201. doi: 10.1111/j.1442-200x.2010.03224.x</mixed-citation></ref><ref id="B12"><label>12.</label><mixed-citation>Landry A., Docherty P., Ouellette S., Cartier L.J. Causes and outcomes of markedly elevated C-reactive protein levels. Can. Fam. Physician., 2017, vol. 63, no. 6, pp. e316–e323.</mixed-citation></ref><ref id="B13"><label>13.</label><mixed-citation>Lips P., Cashman K.D., Lamberg-Allardt C., Bischoff-Ferrari H.A., Obermayer-Pietsch B., Bianchi M.L., Stepan J., El-Hajj Fuleihan G., Bouillon R. Current vitamin D status in European and Middle East countries and strategies to prevent vitamin D deficiency: a position statement of the European Calcified Tissue Society. Eur. J. Endocrinol., 2019, vol. 180, no. 4, pp. 23–54. doi: 10.1530/EJE-18-0736</mixed-citation></ref><ref id="B14"><label>14.</label><mixed-citation>Liu P.T., Stenger S., Li H., Wenzel L., Tan B.H., Krutzik S.R., Ochoa M.T., Schauber J., Wu K., Meinken C., Kamen D.L., Wagner M., Bals R., Steinmeyer A., Zügel U., Gallo R.L., Eisenberg D., Hewison M., Hollis B.W., Adams J.S., Bloom B.R., Modlin R.L. Toll-like receptor triggering of a vitamin D-mediated human antimicrobial response. Science, 2006, vol. 311, no. 5768, pp. 1770–1773. doi: 10.1126/science.1123933</mixed-citation></ref><ref id="B15"><label>15.</label><mixed-citation>Mamani M., Muceli N., Ghasemi Basir H.R., Vasheghani M., Poorolajal J. Association between serum concentration of 25-hydroxyvitamin D and community-acquired pneumonia: a case-control study. Int. J. Gen. Med., 2017, vol. 10, pp. 423–429. doi: 10.2147/IJGM.S149049</mixed-citation></ref><ref id="B16"><label>16.</label><mixed-citation>Martens P.-J., Gysemans C., Verstuyf A., Mathieu C. Vitamin D’s effect on immune function. Nutrients, 2020, vol. 12, no. 5: 1248. doi: 10.3390/nu12051248</mixed-citation></ref><ref id="B17"><label>17.</label><mixed-citation>Mukaka M.M. Statistics corner: a guide to appropriate use of correlation coefficient in medical research. Malawi Med. J., 2012, vol. 24, no. 3, pp. 69–71.</mixed-citation></ref><ref id="B18"><label>18.</label><mixed-citation>Nnoaham K.E., Clarke A. Low serum vitamin D levels and tuberculosis: a systematic review and meta-analysis. Int. J. Epidemiol., 2008, vol. 37, no. 1, pp. 13–19. doi: 10.1093/ije/dym247</mixed-citation></ref><ref id="B19"><label>19.</label><mixed-citation>Palacios C., Gonzalez L. Is vitamin D deficiency a major global public health problem? J. Steroid Biochem. Mol. Biol., 2014, vol. 144, pt. A, pp. 38–45. doi: 10.1016/j.jsbmb.2013.11.003</mixed-citation></ref><ref id="B20"><label>20.</label><mixed-citation>Pilz S., Rutters F., Dekker J.M. Disease prevention: vitamin D trials. Science, 2012, vol. 338, no. 6109: 883. doi: 10.1126/science.338.6109.883-c</mixed-citation></ref><ref id="B21"><label>21.</label><mixed-citation>Pletz M.W., Terkamp C., Schumacher U., Rohde G., Schütte H., Welte T., Bals R.; CAPNETZ-Study Group. Vitamin D deficiency in community-acquired pneumonia: low levels of 1,25(OH)2 D are associated with disease severity. Respir. Res., 2014, vol. 15, no. 1: 53. doi: 10.1186/1465-9921-15-53</mixed-citation></ref><ref id="B22"><label>22.</label><mixed-citation>Rolf L., Muris A.H., Hupperts R., Damoiseaux J. Vitamin D effects on B cell function in autoimmunity. Ann. N.Y. Acad. Sci., 2014, vol. 1317, pp. 84–91. doi: 10.1111/nyas.12440</mixed-citation></ref><ref id="B23"><label>23.</label><mixed-citation>Ross A.C., Manson J.E., Abrams S.A., Aloia J.F., Brannon P.M., Clinton S.K., Durazo-Arvizu R.A., Gallagher J.C., Gallo R.L., Jones G., Kovacs C.S., Mayne S.T., Rosen C.J., Shapses S.A. The 2011 report on dietary reference intakes for calcium and vitamin D from the Institute of Medicine: what clinicians need to know. J. Clin. Endocrinol. Metab., 2011, vol. 96, no. 1, pp. 53–58. doi: 10.1210/jc.2010-2704</mixed-citation></ref><ref id="B24"><label>24.</label><mixed-citation>Sakka A.S.E., Iman S.S., Amer H.A., Moustafa S.A. Vitamin D deficiency and low hemoglobin level as risk factors for severity of acute lower respiratory tract infections in Egyptian children: a case-control study. Egypt. Pediatr. Assoc Gaz., 2014, vol. 62, pp. 1–7. doi: 10.1016/j.epag.2013.12.001</mixed-citation></ref><ref id="B25"><label>25.</label><mixed-citation>Şişmanlar T., Aslan A.T., Gülbahar Ö., Özkan S. The effect of vitamin D on lower respiratory tract infections in children. Turk. Arch. Pediatr., 2016, vol. 51, no. 2, pp. 94–99. doi: 10.5152/TurkPediatriArs.2016.3383</mixed-citation></ref><ref id="B26"><label>26.</label><mixed-citation>Van den Berghe G., Van Roosbroeck D., Vanhove P., Wouters P.J., De Pourcq L., Bouillon R. Bone turnover in prolonged critical illness: effect of vitamin D. J. Clin. Endocrinol. Metab., 2003, vol. 88, no. 10, pp. 4623–4632. doi: 10.1210/jc.2003-030358</mixed-citation></ref><ref id="B27"><label>27.</label><mixed-citation>WHO. WHO-UNICEF Estimates of National Immunization Coverage (WUENIC), 1980–2019 (July, 2020). URL: https://apps.who.int/immunization_monitoring/globalsummary/timeseries/tswucoveragedtp3.html</mixed-citation></ref><ref id="B28"><label>28.</label><mixed-citation>WHO. Pneumonia and diarrhea progress report. URL: https://www.who.int/news-room/fact-sheets/detail/pneumonia (02.08.2019)</mixed-citation></ref></ref-list></back></article>
