METHODS: This was a prospective study conducted at a tertiary hospital in Malaysia, from 1st August 2010 until 31st July 2011. Children aged between 1 mo and 12 y who were admitted for CAP and had blood cultures performed before starting intravenous antibiotics were recruited. Children with congenital pneumonia, immunodeficiency, chronic cardiac or respiratory disorders, nosocomial pneumonia or those on corticosteroids, were excluded. Decision for admission was made by the attending Accident and Emergency physician.

RESULTS: One hundred and seventy-one children were enrolled. The median age was 13 mo (range: 38 d-10 y 3 mo) and 59 % were males. Blood cultures were positive in 1.2 % (2/171) of patients while the contamination rate was 1.8 % (3/171). Doctors altered antibiotics based on blood culture results in only one patient.

METHODOLOGY: Respiratory secretions were examined for chlamydiae by cell culture, enzyme-linked immunosorbent assay and polymerase chain reaction-enzyme immunoassay. Sera were tested by micro-immunofluorescence for chlamydial IgG, IgM and IgA. Other bacterial and viral pathogens were also looked for by standard cultural and serological methods.

RESULTS: Of 87 patients aged 2 months-3 years, an aetiologic diagnosis was made in 41 (47.1%). C. pneumoniae and C. trachomatis were each detected in 1 (1.2%) of the patients. Among common bacterial pathogens, Haemophilus influenzae (13.8%) and Streptococcus pneumoniae (8.1%) were the most frequently identified. Respiratory viruses and elevated Mycoplasma pneumoniae antibodies were found in 10.3% and 9.1% of patients, respectively.