Role of bacterial infection in the exacerbation of acute or prolonged asthma attack in children

Quantitatively cultured bacteria in sputum sampled from asthmatic children aged 0–14 years was examined to determine whether there is a relationship between asthmatic states and bacterial species present in the respiratory tract. We used cytological examination to improve the specificity of pathogens cultured in sputum. Asthmatic children were divided into three groups: (i) group 1, acute asthma attack (n = 191); (ii) group 2, prolonged asthma attack (n = 68); and (iii) group 3, pneumonia without asthma attack (n = 39). The number of specimens was 212, 75 and 44 for groups 1, 2 and 3, respectively. The number of specimens with pathogenic bacteria present in group 1 decreased with age, from 36.8% in infants under 1 year of age to 8.7% in children over the age of 9 years. The species of bacteria in group 1 were Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis and these were distributed evenly in the samples. In group 2, pathogenic bacteria were present in 34.7% of patients (26/75), peaking at over 40% among children between 4 and 8 years of age. The presence of H. influenzae was dominant in group 2. The percentage of pathogenic bacteria present in group 3 specimens was 40.9%. The data suggest that there is a significant relationship between the presence of bacteria in sputum and clinical symptoms, such as fever and pneumonic episodes, during acute asthma attacks.