Epiglottitis due to ampicillin-tolerant Haemophilus influenzae type b

Area of Science:

• Microbiology
• Infectious Diseases
• Pharmacology

Background:

• Beta-lactam antibiotic tolerance is a known phenomenon in staphylococci and enterococci.
• Its occurrence and clinical significance in Haemophilus influenzae have not been previously reported.
• Haemophilus influenzae type b (Hib) remains a significant pathogen, particularly in unvaccinated populations.

Observation:

• A case of bacteremic epiglottitis caused by Haemophilus influenzae type b was observed.
• The causative strain was identified as beta-lactamase-negative and exhibited tolerance to ampicillin.
• The patient's clinical condition improved with ampicillin monotherapy.

Findings:

• The ampicillin-tolerant Haemophilus influenzae type b strain was susceptible to moxalactam, cefotaxime, and rifampin.
• Ampicillin therapy alone was clinically effective in curing the bacteremic epiglottitis.
• Rifampin administration successfully eradicated pharyngeal carriage of the organism.

Implications:

• This case highlights the potential for beta-lactam tolerance in Haemophilus influenzae and its clinical relevance.
• It suggests that while ampicillin may be effective, alternative or combination therapies might be considered in certain tolerant strains.
• Rifampin demonstrates efficacy in eliminating nasopharyngeal carriage, a crucial factor in disease transmission.