Acute primary Chlamydophila pneumoniae bronchitis and bronchial hyperresponsiveness in young nonasthmatic Thai military recruits.
BACKGROUND
A correlation between chronic Chlamydophila pneumoniae infection and chronic airway diseases has been suggested by several studies, but direct evidence to support the link between acute Cpneumoniae infection and new-onset asthma is insufficient.


OBJECTIVE
To determine the association between C. pneumoniae infection and subsequent bronchial hyperresponsiveness (BHR) and hence asthma.


METHODS
We studied 110 Thai military conscripts during an epidemic of Cpneumoniae infection in Thailand, from November 1, 1998, through February 28, 1999. The diagnosis was based on a standardized microimmunofluorescence technique. Spirometry and methacholine challenge tests (MCTs) were conducted. This cohort study excluded all conscripts with preexisting positive MCTs.


RESULTS
Ninety-three percent of the conscripts presented with an acute cough of a mean duration of 15.2 days. The pattern of serologic response revealed that 83% had acute primary infections and 10% had acute reinfections. Mean forced expiratory volume in 1 second was 99.5%, with an improvement of 1.8% after bronchodilator administration. Only 3.6% revealed small airways disease (forced expiratory flow between 25% and 75% of <65%) on spirometry. Methacholine challenge tests failed to demonstrate BHR in all conscripts, and none had developed a new-onset wheeze (physician-diagnosed asthma) at up to 2 years of follow-up.


CONCLUSIONS
This study demonstrates that cough in patients with acute primary Cpneumoniae infection is not associated with BHR among previously healthy adults. The pathogenetic mechanism by which organisms cause coughing and wheezing in acute bronchitis seems to be different among causative respiratory pathogens.
Department of Pulmonary and Critical Care Medicine, Bumrungrad International Hospital, Wattana, Bangkok, Thailand. suttithawil@yahoo.com
Wudthichai
W
Suttithawil
Yongyudh
Y
Ploysongsang
Pongpun
P
Nunthapisud
Ratanaporn
R
Fuangtong
D000208:Acute Disease; D000328:Adult; D016535:Bronchial Hyperreactivity / Q000453:epidemiology / Q000382:microbiology*; D001985:Bronchial Provocation Tests; D023521:Chlamydophila Infections / Q000150:complications* / Q000453:epidemiology; D016993:Chlamydophila pneumoniae; D003371:Cough / Q000382:microbiology; D006801:Humans; D008297:Male; D008889:Military Personnel; D018410:Pneumonia, Bacterial / Q000150:complications* / Q000453:epidemiology; D012129:Respiratory Function Tests; D013785:Thailand