title: Prevalence of silent gastroesophageal reflux in association with recurrent lower respiratory tract infections.
abstract: OBJECTIVE
  Gastroesophageal reflux (GER) has long been associated with pulmonary symptoms and diseases. This retrospective analysis was undertaken to determine the prevalence of GER detected by gastroesophageal scintigraphy in children with recurrent lower respiratory tract infections but none of the typical gastroesophageal symptoms of GER.
  
  
  METHODS
  A total of 312 children (mean age, 2.36 years; age range, 4 months to 11 years) were evaluated. All studies were performed using Tc-99m sulfur colloid (3.7 to 7.4 MBq; 100 to 200 microCi).
  
  
  RESULTS
  Of 312 children, 108 (34.6%) had GER on gastroesophageal scintigraphy. The children were separated into four groups, depending on their age. Group 1 (119 children, younger than 1 year), group 2 (131 children, ages 1 to 3 years), group 3 (36 children, ages 3 to 6 years), and group 4 (26 children, ages 6 to 12 years) showed silent GER with prevalences of 38.7%, 37.4%, 22.2%, and 19.2%, respectively. Because physiologic GER is common in children younger than 18 months, we also analyzed the prevalence of GER in children younger than 18 months and older than 18 months of age. The prevalences of GER in these groups were 41.7% and 24.6%, respectively.
  
  
  CONCLUSIONS
  A significant number of children with recurrent lower respiratory tract infection have scintigraphic evidence of GER. This high prevalence, even in children older than 18 months, cannot be ignored. Prospective studies including many patients are needed to establish the exact role of GER in these patients.
authors.affiliation: Department of Nuclear Medicine, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Eluvathingal J
authors.initials: EJ
authors.lastname: Thomas
authors.forename: Rakesh
authors.initials: R
authors.lastname: Kumar
authors.forename: J Bharathi
authors.initials: JB
authors.lastname: Dasan
authors.forename: Chandershekar
authors.initials: C
authors.lastname: Bal
authors.forename: Sushil K
authors.initials: SK
authors.lastname: Kabra
authors.forename: Arun
authors.initials: A
authors.lastname: Malhotra
mesh_terms: D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D004947:Esophagus / Q000000981:diagnostic imaging; D005260:Female; D005764:Gastroesophageal Reflux / Q000150:complications / Q000000981:diagnostic imaging / Q000453:epidemiology*; D006801:Humans; D007223:Infant; D008297:Male; D015995:Prevalence; D011877:Radionuclide Imaging; D019275:Radiopharmaceuticals; D012008:Recurrence; D012141:Respiratory Tract Infections / Q000150:complications* / Q000453:epidemiology; D012189:Retrospective Studies; D013671:Technetium Tc 99m Sulfur Colloid
chemical_list: D019275:Radiopharmaceuticals; D013671:Technetium Tc 99m Sulfur Colloid