NEW YORK (Reuters Health) - Viable Chlamydia pneumoniae organisms are frequently present in bronchial lavage fluid from children with asthma and other respiratory disorders, a new study shows.
“We were surprised by the finding that 54% of children with various chronic respiratory diseases harbored Chlamydia in their lungs as determined by polymerase chain reaction (PCR),” Dr. Wilmore C. Webley from the University of Massachusetts in Amherst, told Reuters Heath.
“More importantly, this study shows for the first time that these organisms are infectious,” he said, noting that 31% of all Chlamydia positive samples by PCR grew in culture on a macrophage cell substrate.
“This is significant, since the youngest patient with viable Chlamydia was 6 months old, suggesting that these organisms can infect early in life at a time when the infant’s immune response is not well developed and can then persist for long periods in the lungs.”
Of the 70 children who participated in the study, 42 had asthma whereas 28 had various respiratory disorders including aspiration bronchitis, airway anomalies, gastroesophageal reflux disease, cystic fibrosis, and recurrent pneumonia of unknown etiology.
Forty percent of PCR-positive samples and 20% of culture-positive samples were from children with asthma. According to the investigators, there was a strong correlation between lavage culture positivity for Chlamydia and elevated total IgE levels. "[This] implies that potentially a combination of elevated serum IgE titers and the presence of C. pneumoniae organisms could be used to assess disease severity,” Dr. Webley said.
It also points to the “need to evaluate the usefulness of antibiotics as part of the overall treatment regimen for certain types of chronic respiratory diseases in children, especially when they exist in combination with respiratory chlamydial infection,” he added.
Dr. Webley’s team also detected Chlamydia in 24 of 70 (34%) cultured peripheral blood specimens obtained compared with just 8 of 70 (11%) matched nonrespiratory control blood samples. Seventeen (24%) of the positive blood cultures from the respiratory group came from children with asthma.
Summing up, Dr. Webley noted that while C. pneumoniae has been linked with a number of chronic infectious diseases, including the exacerbation of asthma symptoms, the majority of the published work to date has focused on adult onset asthma.
"[Our] studies extend detailed findings to children and provide support to the suspicions of researchers that chlamydial infections might play an important role in the exacerbation of chronic respiratory disease symptoms including asthma.”
The study appears in the May 15th issue of the American Journal of Respiratory and Critical Care Medicine.
Source: Am J Respir Crit Care Med 2005;171:1083-1088. [ Google search on this article ]
MeSH Headings:Chlamydia Infections: Chlamydiaceae Infections: Sexually Transmitted Diseases, Bacterial: Polymerase Chain Reaction: Gram-Negative Bacterial InfectionsCopyright © 2002 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content, including by framing or similar means, is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon. Reuters and the Reuters sphere logo are registered trademarks and trademarks of the Reuters group of companies around the world.
