Rate of Chlamydia trachomatis and Chlamydia pneumoniae in paediatric respiratory infections

¹ Dept of Microbiology, University of Massachusetts Amherst, MA
² Dept of Pathology, Baystate Medical Center, Springfield, MA
³ Dept of paediatric Pulmonology, Baystate Medical Center, Springfield, MA

^* To whom correspondence should be addressed. E-mail: wilmore{at}microbio.umass.edu.

	Abstract

An emerging body of evidence suggests that half of asthma in both children and adults is associated with chronic lung infection. The aim of this study was to determine the frequency of viable Chlamydia pneumoniae (Cp) and trachomatis (Ct) in the respiratory tracts of paediatric patients with chronic respiratory diseases.

Bronchoalveolar lavage fluid (BAL) obtained from 182 children undergoing bronchoscopy for clinical reasons, were assayed using PCR analysis, in vitro tissue culture and immunofluorescence staining for the presence of Cp and Ct.

Chlamydia-specific DNA was detected by PCR in 124/182 (68%) patients; 79 were positive for Cp, 77 for Ct and 32 for both organisms; seventy-five patients had cultivable Chlamydia. Ct DNA prevalence decreased, whereas Cp positivity generally increased with age. Fifty-nine of 128 asthma patients and 16/54 non-asthmatics were Chlamydia culture-positive [p=0.048]. When the patients were divided into inflammatory versus non-inflammatory airway disease, there were 69/150 [46%] and 6/32 [18%] BAL samples with cultivable Chlamydia respectively [p=0.005].

Viable Cp and Ct occur frequently in children with chronic respiratory diseases and may be more prevalent in asthma patients. To our knowledge, this is the first report of viable Ct in the lungs of children.