Related Experiment Videos
The bacteriology of acute otitis media in children with special reference to Streptococcus pneumoniae as studied by
Abstract:
The middle ear fluid (MEF) was studied during an acute attack of otitis media in 519 children, aged 3 months to 6 years. Streptococcus pneumoniae (Pn) was cultured from 39% of the cases; serotypes 19, 6, 3 and 23 were the most common. Haemophilus influenzae (Hi) was cultured in 12%; only 2/64 strains were of type b. Pn were found equally often in all age groups, but Hi were significantly less often isolated in children older than 3 years. The number of negative cultures increased with the age of the child. Pneumococcal capsular polysaccharide was detected with counterimmunoelectrophoresis and/or latex agglutination in 83% of the MEFs from which Pn were cultured, but also in about one third of the MEFs from which no bacteria could be grown. Altogether, with these methods combined Pn were implicated in nearly 60% of the cases of acute otitis media. Gram staining showed polymorphonuclear leucocytes in 85% of pneumococcal otitis cases that were verified by culture but also in 72% of the cases from which no bacteria could be cultured, supporting the contention that also these latter are usually caused by bacteria.
Insights
Streptococcus pneumoniae (Pn) was the primary cause of acute otitis media in children, identified in nearly 60% of cases. Haemophilus influenzae (Hi) was less common, particularly in older children.
Area of Science:
- Pediatrics
- Infectious Diseases
- Microbiology
Background:
- Acute otitis media (AOM) is a common childhood infection.
- Identifying causative pathogens is crucial for effective treatment.
Purpose of the Study:
- To investigate the bacterial pathogens responsible for acute otitis media in young children.
- To determine the prevalence of Streptococcus pneumoniae and Haemophilus influenzae in middle ear fluid (MEF).
Main Methods:
- Culturing middle ear fluid (MEF) from 519 children aged 3 months to 6 years with acute otitis media.
- Utilizing counterimmunoelectrophoresis and latex agglutination to detect pneumococcal capsular polysaccharide.
- Performing Gram staining to identify polymorphonuclear leucocytes.
Main Results:
- Streptococcus pneumoniae (Pn) was identified in 39% of cases, with serotypes 19, 6, 3, and 23 being most common.
- Haemophilus influenzae (Hi) was isolated in 12% of cases; only two strains were type b.
- Pn was equally prevalent across age groups, while Hi decreased in children over 3 years old.
- Pneumococcal antigen was detected in 83% of Pn-positive cultures and in about one-third of culture-negative cases.
- Combined methods implicated Pn in nearly 60% of AOM cases.
- Polymorphonuclear leucocytes were present in 85% of culture-confirmed Pn cases and 72% of culture-negative cases.
Conclusions:
- Streptococcus pneumoniae is the predominant pathogen in acute otitis media in children.
- Detection of pneumococcal antigen and inflammatory cells supports bacterial etiology even in culture-negative cases.
- Age influences the isolation rates of specific pathogens like Haemophilus influenzae.