YOUNG MALAYSIAN CHILDREN WITH LOWER RESPIRATORY-TRACT INFECTIONS SHOWLOW INCIDENCE OF CHLAMYDIAL INFECTION

Objective: The incidence of Chlamydia pneumoniae and Chlamydia trachom atis infection was studied among infants and young children admitted t o hospital for the management of lower respiratory tract infections, o ver a 12 month period. Methodology: Respiratory secretions were examin ed for chlamydiae by cell culture, enzyme-linked immunosorbent assay a nd polymerase chain reaction-enzyme immunoassay. Sera were tested by m icro-immunofluorescence for chlamydial IgG, IgM and IgA. Other bacteri al and viral pathogens were also looked for by standard cultural and s erological methods. Results: Of 87 patients aged 2 months-3 years, an aetiologic diagnosis was made in 41 (47.1%), C. pneumoniae and C. trac homatis were each detected in 1 (1.2%) of the patients. Among common b acterial pathogens, Haemophilus influenzae (13.8%) and Streptococcus p neumoniae (8.1%) were the most frequently identified. Respiratory viru ses and elevated Mycoplasma pneumoniae antibodies were found in 10.3% and 9.1% of patients, respectively. Conclusion: Chlamydiae are infrequ ent causes of community-acquired acute lower respiratory tract infecti ons in infants and very young children in Malaysia.