title: Comparisons of etiology and diagnostic tools of lower respiratory tract infections in hospitalized young children in Southern Taiwan in two seasons.
abstract: BACKGROUND
  Lower respiratory tract infections (LRTIs) play an important role in pediatric diseases; however, there are limited data about LRTIs in Southern Taiwan. This study aimed to investigate the clinical and epidemiological data of LRTIs in this area.
  
  
  METHODS
  Children aged under 5 years who were hospitalized at a medical center in Southern Taiwan with acute LRTIs from July 2010 to October 2010 (summer) and from March 2011 to May 2011 (spring) were prospectively enrolled. Nasopharyngeal aspirates were obtained and sent for viral cultures, multiplex polymerase chain reaction (PCR), and traditional quick tests. The clinical features, laboratory data, and imaging findings were recorded and analyzed.
  
  
  RESULTS
  A total of 90 children were enrolled, 70 of whom had detectable pathogens. The positive rate of conventional viral and bacterial cultures was 25.6%, which increased to 77.77% after combining with the two multiplex PCR methods. Adenovirus and enterovirus were the most common viral etiologies identified (26.5% of cases) and Streptococcus pneumoniae was the leading bacterial etiology (46.4%). The seasonal trend of viral infections in Southern Taiwan was different from Northern Taiwan. There were no differences in demographic data, severity of disease, or hospital stay between single and mixed infections. A similar result was found between nonpneumococcal and pneumococcal infections.
  
  
  CONCLUSIONS
  Viral infections were the main etiologies of LRTIs in young children. Multiplex PCR methods are rapid assays that can increase the diagnostic yield rate. Mixed infections do not seem to affect the severity of disease. Early detection may aid clinicians in appropriate decision-making and treatment.
authors.affiliation: Department of Pediatrics, Kaohsiung Veterans General Hospital, Taiwan.
authors.forename: Chih-An
authors.initials: CA
authors.lastname: Chou
authors.affiliation: Department of Pediatrics, Kaohsiung Veterans General Hospital, Taiwan.
authors.forename: Ting-I
authors.initials: TI
authors.lastname: Lin
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Pingtung Branch of Kaohsiung Veterans General Hospital, Pingtung, Taiwan.
authors.forename: Yu-Shen
authors.initials: YS
authors.lastname: Chen
authors.affiliation: Department of Pediatrics, Kaohsiung Veterans General Hospital, Taiwan.
authors.forename: Po-Yen
authors.initials: PY
authors.lastname: Liu
authors.affiliation: Department of Pediatrics, Kaohsiung Veterans General Hospital, Taiwan; Department of Pediatrics, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. Electronic address: yf5012@hotmail.com.
authors.forename: Yung-Feng
authors.initials: YF
authors.lastname: Huang
authors.affiliation: Department of Pediatrics, Kaohsiung Veterans General Hospital, Taiwan.
authors.forename: Ying-Yao
authors.initials: YY
authors.lastname: Chen
authors.affiliation: Department of Pediatrics, Kaohsiung Veterans General Hospital, Taiwan.
authors.forename: Kai-Sheng
authors.initials: KS
authors.lastname: Hsieh
authors.affiliation: Section of Infectious Diseases, Department of Internal Medicine, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Yao-Shen
authors.initials: YS
authors.lastname: Chen
authors.affiliation: Department of Education and Research, Kaohsiung Veterans General Hospital, Kaohsiung, Taiwan.
authors.forename: Luo-Ping
authors.initials: LP
authors.lastname: Ger
mesh_terms: D000256:Adenoviridae / Q000302:isolation & purification; D002675:Child, Preschool; D004770:Enterovirus / Q000302:isolation & purification; D005260:Female; D006760:Hospitalization; D006801:Humans; D007223:Infant; D008297:Male; D060885:Multiplex Polymerase Chain Reaction; D011008:Pneumococcal Infections / Q000453:epidemiology* / Q000382:microbiology; D011446:Prospective Studies; D012141:Respiratory Tract Infections / Q000175:diagnosis* / Q000453:epidemiology* / Q000382:microbiology / Q000821:virology; D012621:Seasons; D013296:Streptococcus pneumoniae / Q000302:isolation & purification; D013624:Taiwan / Q000453:epidemiology; D014777:Virus Diseases / Q000453:epidemiology* / Q000821:virology
keywords: Southern Taiwan; children; lower respiratory tract infection; multiplex polymerase chain reaction; seasonality