Increasing bacterial resistance in pediatric acute conjunctivitis (1997-1998)
Related Experiment Video
Updated: Aug 11, 2026

Following in Real Time the Impact of Pneumococcal Virulence Factors in an Acute Mouse Pneumonia Model Using Bioluminescent Bacteria
Published on: February 23, 2014
S L Block1, J Hedrick, R Tyler
1Kentucky Pediatric Research, Inc., Bardstown, Kentucky 40004, USA. SLBlock@pol.net
Insights
Pediatric conjunctivitis is often caused by Haemophilus influenzae and Streptococcus pneumoniae. High resistance rates were observed, with 69% of H. influenzae producing beta-lactamase and 32% of S. pneumoniae showing penicillin non-susceptibility.
Area of Science:
- Ophthalmology
- Microbiology
- Pediatrics
Background:
- Pediatric conjunctivitis is a common condition.
- Haemophilus influenzae and Streptococcus pneumoniae are primary causative pathogens.
- Understanding antimicrobial resistance patterns is crucial for effective treatment.
Purpose of the Study:
- To determine the current antimicrobial resistance levels of H. influenzae and S. pneumoniae in pediatric conjunctivitis.
- To assess the prevalence of beta-lactamase production in H. influenzae.
- To evaluate the penicillin susceptibility of S. pneumoniae isolates.
Main Methods:
- Prospective culture of acute conjunctivitis cases in 250 pediatric patients (January 1997-March 1998).
- Isolation and identification of bacterial pathogens.
- Antimicrobial susceptibility testing, including beta-lactamase detection and penicillin susceptibility testing.
Main Results:
- H. influenzae (42%) and S. pneumoniae (30%) were the most common pathogens.
- 69% of H. influenzae strains produced beta-lactamase.
- 32% of S. pneumoniae isolates were non-susceptible to penicillin (26% resistant, 6% intermediate).
- H. influenzae was frequently associated with conjunctivitis-otitis syndrome (57% of cases).
- Ciprofloxacin, ofloxacin, and tetracycline showed the highest in vitro activity.
Conclusions:
- H. influenzae remains a primary pathogen in pediatric conjunctivitis, with high rates of beta-lactamase production.
- A significant proportion of S. pneumoniae isolates exhibit penicillin non-susceptibility.
- Antimicrobial resistance patterns necessitate careful selection of treatments for pediatric conjunctivitis.
Abstract:
We sought to determine the current level of resistance in Haemophilus influenzae and Streptococcus pneumoniae, the primary pathogens of pediatric conjunctivitis. Between January 1997 and March 1998, we prospectively cultured acute conjunctivitis in 250 ambulatory pediatric patients from rural Kentucky whose average age was 24.3 months. In those 250 cases, 106 H. influenzae (42% of the total) and 75 S. pneumoniae (30% of the total) pathogens were isolated, with no growth or no pathogen resulting in 79 cases (32% of the total). Beta-lactamase was detected in 60 (69%) of 87 tested strains of H. influenzae. Among 65 isolates of S. pneumoniae tested for penicillin susceptibility, 44 (68%) were susceptible, 17 (26%) were resistant, and 4 (6%) were intermediate. Conjunctivitis with acute otitis media was observed in 97 patients (39%), and H. influenzae was recovered in 57% of these 97 cases. As for in vitro activity, ciprofloxacin, ofloxacin, and tetracycline were the most active; and gentamicin, tobramycin, polymyxin B-trimethoprim, and polymyxin B-neomycin were intermediately active. Sulfamethoxazole possessed no activity against either pathogen. Beta-lactamase production was detected in 69% of H. influenzae strains, which still remains the primary causative pathogen of both conjunctivitis and conjunctivitis-otitis syndrome. Penicillin-nonsusceptible S. pneumoniae was observed in 32% of 65 patients with S. pneumoniae conjunctivitis, with most strains being penicillin resistant.
Related Concept Videos
Antibiotic Selection
Development of Antibiotic Resistance
Microbiome of the Eye
Mechanism of Antibiotic Resistance in MRSA
Clinical Significance of Antibiotic Resistance

