title: Increased rates of intense nasopharyngeal bacterial colonization of Vietnamese children with radiological pneumonia.
abstract: Acute lower respiratory infection (ALRI), primarily pneumonia, is the leading cause of death in children under the age of five. Bacterial ALRI is preceded by asymptomatic bacterial colonization. Bacterial colonization, therefore, may have an important role in the development of pneumonia in children. This case-control study was conducted in order to determine if intense bacterial colonization was increased in the nasopharynx of pediatric patients with ALRI. One hundred-sixty four pediatric patients with ALRI and 70 healthy children < 5 years of age were enrolled in Hanoi, Vietnam between 2001 and 2002. Bacterial pathogens were isolated from nasopharyngeal secretions and quantitatively cultured. Of 164 patients, 91 were diagnosed as having radiological pneumonia (PN group) and 73 as having acute bronchitis (AB group). Intense growth of any bacterial pathogen (>or= 10(6) colony-forming units/ml) was highest in the PN group (49.4%), followed by the AB group (28.8%), with healthy children having the lowest (17.1%). Patients with intense bacterial growth were more likely to develop pneumonia, but not acute bronchitis, than were patients with light or no bacterial growth. The results of this case-control study suggest that the vertical spread of intense bacterial pathogens colonized in the nasopharynx to the lower airway leads to bacterial pneumonia in children under the age of five.
authors.affiliation: National Institute of Hygiene and Epidemiology, hanoi, Vietnam.
authors.forename: Dang Duc
authors.initials: DD
authors.lastname: Anh
authors.forename: Phan Le Thanh
authors.initials: Ple T
authors.lastname: Huong
authors.forename: Kiwao
authors.initials: K
authors.lastname: Watanabe
authors.forename: Nguyen Thu
authors.initials: NT
authors.lastname: Nguyet
authors.forename: Nguyen Thu Hien
authors.initials: NT
authors.lastname: Anh
authors.forename: Ngo Thi
authors.initials: NT
authors.lastname: Thi
authors.forename: Nguyen Tien
authors.initials: NT
authors.lastname: Dung
authors.forename: Doan Mai
authors.initials: DM
authors.lastname: Phuong
authors.forename: Susumu
authors.initials: S
authors.lastname: Tanimura
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Ohkusa
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Nagatake
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Watanabe
authors.forename: Kazunori
authors.initials: K
authors.lastname: Oishi
mesh_terms: D000208:Acute Disease; D000900:Anti-Bacterial Agents / Q000008:administration & dosage; D001419:Bacteria / Q000302:isolation & purification*; D001991:Bronchitis / Q000175:diagnosis; D016022:Case-Control Studies; D002675:Child, Preschool; D005260:Female; D006090:Gram-Negative Bacteria / Q000254:growth & development / Q000302:isolation & purification; D006094:Gram-Positive Bacteria / Q000254:growth & development / Q000302:isolation & purification; D006801:Humans; D008297:Male; D009305:Nasopharynx / Q000382:microbiology*; D018410:Pneumonia, Bacterial / Q000000981:diagnostic imaging* / Q000401:mortality; D011859:Radiography; D012141:Respiratory Tract Infections / Q000175:diagnosis / Q000382:microbiology; D014744:Vietnam / Q000453:epidemiology
chemical_list: D000900:Anti-Bacterial Agents