title: Serum Vitamin D Levels in Children with Recurrent Respiratory Infections and Chronic Cough.
abstract: OBJECTIVE
  To evaluate serum vitamin D levels in cases of recurrent respiratory infections and chronic cough and to investigate the effect of vitamin D therapy on recurrence of the diseases.
  
  
  METHODS
  This prospective observational study was performed by comparing serum vitamin D levels in children with recurrent respiratory infections, chronic cough and healthy children. One-hundred-one children with chronic cough, ninety-eight children with recurrent respiratory infections and one-hundred-twenty-four healthy children were enrolled in the study. A structured questionnaire was completed to collect data on demography, diet, duration of breastfeeding, vitamin D supplementation and family history for allergic diseases. In patients with low serum vitamin D levels (<20 ng/ml), vitamin D therapy was administered in addition to conventional treatment for the diseases. Patients were followed up for 6 mo and their complaints were evaluated.
  
  
  RESULTS
  Mean serum 25(OH) vitamin D level in the recurrent respiratory infections group was 11.97 ± 4.04 ng/ml, chronic cough group was 13.76 ± 4.81 ng/ml and control group was 31.91 ± 18.79 ng/ml. Comparison of serum 25(OH) vitamin D levels between the study groups revealed a statistically significant difference (p < 0.05). 25(OH)D deficiency in children was associated with increased frequency of recurrent respiratory infections and chronic cough.
  
  
  CONCLUSIONS
  To conclude, administration of supplementary vitamin D may be useful in the treatment and preventation of recurrent respiratory infections and chronic cough.
authors.affiliation: Department of Pediatrics, Baskent University Faculty of Medicine, Ankara, Turkey. beril_ozdemir@yahoo.com.
authors.forename: Beril
authors.initials: B
authors.lastname: Özdemir
authors.affiliation: Department of Pediatric Allergy, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Burcu Tahire
authors.initials: BT
authors.lastname: Köksal
authors.affiliation: Department of Pediatrics, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Nazmi Mutlu
authors.initials: NM
authors.lastname: Karakaş
authors.affiliation: Department of Biostatistics, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Mustafa Agah
authors.initials: MA
authors.lastname: Tekindal
authors.affiliation: Department of Pediatric Allergy, Baskent University Faculty of Medicine, Ankara, Turkey.
authors.forename: Özlem Yılmaz
authors.initials: ÖY
authors.lastname: Özbek
mesh_terms: D002648:Child; D002675:Child, Preschool; D003371:Cough / Q000151:congenital*; D005260:Female; D006801:Humans; D008297:Male; D011446:Prospective Studies; D012141:Respiratory Tract Infections / Q000150:complications*; D014807:Vitamin D; D014808:Vitamin D Deficiency / Q000150:complications*
chemical_list: D014807:Vitamin D
keywords: 25-hydroxyvitamin D; Child; Cough; Recurrent infections
references.citation: Vitam Horm. 2011;86:23-62
references.pmid: 21419266
references.citation: N Engl J Med. 2007 Jul 19;357(3):266-81
references.pmid: 17634462
references.citation: J Paediatr Child Health. 2015 Jun;51(6):614-9
references.pmid: 25394218
references.citation: J Allergy Clin Immunol. 2010 Nov;126(5):1074-6, 1076.e1-4
references.pmid: 21050947
references.citation: Science. 2006 Mar 24;311(5768):1770-3
references.pmid: 16497887
references.citation: J Allergy Clin Immunol. 2007 Jul;120(1):131-6
references.pmid: 17559916
references.citation: Cell Immunol. 2012 Nov;280(1):36-43
references.pmid: 23261827
references.citation: Pediatr Allergy Immunol. 2004 Jun;15(3):242-6
references.pmid: 15209957
references.citation: Pediatr Allergy Immunol. 2011 Sep;22(6):583-9
references.pmid: 21342281
references.citation: Pediatrics. 2012 Sep;130(3):421-8
references.pmid: 22869836
references.citation: J Pediatr Health Care. 2014 Nov-Dec;28(6):572-82; quiz 583-4
references.pmid: 25441970
references.citation: Eur J Endocrinol. 2001 Sep;145(3):351-7
references.pmid: 11517017
references.citation: Zhonghua Er Ke Za Zhi. 2008 Feb;46(2):108-10
references.pmid: 19099683
references.citation: Paediatr Perinat Epidemiol. 2013 Nov;27(6):532-41
references.pmid: 24134527
references.citation: J Paediatr Child Health. 2014 Jul;50(7):512-8
references.pmid: 24943250
references.citation: Pediatrics. 2008 Aug;122(2):398-417
references.pmid: 18676559
references.citation: Allergy Asthma Proc. 2014 Mar-Apr;35(2):95-103
references.pmid: 24717785
references.citation: Eur J Clin Nutr. 2004 Apr;58(4):563-7
references.pmid: 15042122
references.citation: Pediatrics. 2011 Jan;127(1):e180-7
references.pmid: 21187313
references.citation: J Clin Endocrinol Metab. 2009 Jan;94(1):26-34
references.pmid: 18854395
references.citation: Am J Clin Nutr. 2010 May;91(5):1255-60
references.pmid: 20219962
references.citation: Int J Epidemiol. 2004 Dec;33(6):1362-72
references.pmid: 15166188
references.citation: Pediatr Res. 2009 May;65(5 Pt 2):106R-113R
references.pmid: 19190532
references.citation: Ann Pediatr Child Health. 2015;3(1):null
references.pmid: 25938135
references.citation: Acta Paediatr. 2010 Mar;99(3):389-93
references.pmid: 19900174
references.citation: Br J Dermatol. 2011 May;164(5):1078-82
references.pmid: 21087229
references.citation: Paediatr Int Child Health. 2015 May;35(2):151-6
references.pmid: 25331594
references.citation: Indian J Pediatr. 2015 Nov;82(11):991-5
references.pmid: 25967259
references.citation: Epidemiol Infect. 2006 Dec;134(6):1129-40
references.pmid: 16959053