title: The effect of vitamin D on lower respiratory tract infections in children.
abstract: OBJECTIVE
  Lower respiratory tract infections including mainly pneumonia represent an important public health problem leading to high mortality and mobidity rates in children aged below five years in developing countries including our country. Vitamin D deficiency has been associated with increased risk of rickets/osteomalacia, various cancers, autoimmune diseases, hyperproliferative skin diseases, cardiovascular system diseases and infectious diseases. Vitamin D has an important role in cellular and humoral immunity and pulmonary functions. Vitamin D deficiency and lower respiratory tract infection are common health problems in children in our country and no clinical study investigating the relationship between these problems has been conducted so far. In this case-control study, we aimed to assess the association between vitamin D level and lower respiratory tract infection in children.
  
  
  METHODS
  Sixty-three children aged between six months and five years with lower respiratory infections and 59 age-matched children who had no history of respiratory symptoms in the last month and no accompanying chronic disease were compared in terms of vitamin D levels. The children in the patient group were also evaluated by the clinical picture.
  
  
  RESULTS
  No significant correlation was found between vitamin D levels and lower respiratory tract infection in terms of disease and its severity. However, it was found that vitamin D deficiency/ insufficiency was observed with a high rate in all children included in the study.
  
  
  CONCLUSIONS
  Although no correlation was found between vitamin D level and lower respiratory tract infection, it is recommended that vitamin D level should be measured in children with lower respiratory tract infection and vitamin D supplementation should be given to all children especially in winter months based on the fact that the level of vitamin D was lower than normal in approximately half of the children included in the study and considering the effects of vitamin D on infections, pulmonary functions and immunity.
authors.affiliation: Division of Pediatric Pulmonology, Department of Pediatrics, Gazi University School of Medicine, Ankara, Turkey.
authors.forename: Tuğba
authors.initials: T
authors.lastname: Şişmanlar
authors.affiliation: Division of Pediatric Pulmonology, Department of Pediatrics, Gazi University School of Medicine, Ankara, Turkey.
authors.forename: Ayşe Tana
authors.initials: AT
authors.lastname: Aslan
authors.affiliation: Department of Medical Biochemistry, Gazi University School of Medicine, Ankara, Turkey.
authors.forename: Özlem
authors.initials: Ö
authors.lastname: Gülbahar
authors.affiliation: Department of Public Health, Gazi University School of Medicine, Ankara, Turkey.
authors.forename: Seçil
authors.initials: S
authors.lastname: Özkan
keywords: Child; lower respiratory tract infection; vitamin D