Clinical Research Of Bordetella Pertussis Infection In Infants

Objectives:To explore the clinical manifestations and epidemiological profiles of Bordetella pertussis (B.pertussis) infection in infants and improve our knowledge to early diagnosis and treatment.Methods:Using a retrospective analysis method, we collected data on 142 hospitalized infants with B.pertussis infection in Shenzhen Children’s Hospital from 2011 to 2013, which was confirmed by a real-time Polymerase Chain Reaction (PCR) of nasopharyngeal secretion. The SPSS 19.0 software was used for statistical analysis.Results:Of the 142 hospitalized infants with B.pertussis infection, the ratio of male to female was 2.1:1(96/41).93(65.5%) were aged less than 3 months old,26(18.3%) were 3-6 months old and 23(16.2%) were 6-36 months old. In all,126 patients (88%) were unvaccinated or incompletely vaccinated. The most common clinical manifestation was paroxysmal cough (72.5%). and 6 of which had roaring (4.2%). Peripheral blood WBC level of 83 cases increased, and 75(90.4%) were lymphocytosis. The positive rate of X-ray was 60.6%.108 cases were complicated with bacteria, respiratory virus or mycoplasma pneumonia infection. In the three age groups, the symptom of fever in 0-3 months old group was significantly lower than the other two groups(χ2=11.45, P<0.01;χ2=34.56, P<0.01). Fever associated with other pathogens.Conclusion:B. pertussis is an important pathogen for the infants with persistent cough, especially in unvaccinated or incompletely vaccinated infants, but the clinical manifestation and signs of pertussis are atypical, and other pathogens can be present in hospitalized infants with pertussis, which may lead to fever and a missed diagnosis and delay proper treatment. As a rapid and sensitive method of detecting B.pertussis, PCR may be used in early phase.