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Assessing Respiratory Immune Responses to Haemophilus Influenzae
06:32

Assessing Respiratory Immune Responses to Haemophilus Influenzae

Published on: June 29, 2021

Antimicrobial resistance in Haemophilus influenzae

Stephen Tristram1, Michael R Jacobs, Peter C Appelbaum

  • 1School of Human Life Sciences, University of Tasmania, Locked Bag 1320, Launceston 7250, Australia. Stephen.Tristram@utas.edu.au

Clinical Microbiology Reviews
|April 13, 2007
PubMed

Insights

Haemophilus influenzae exhibits diverse antibiotic resistance, including efflux pumps and beta-lactamase production. Emerging resistance in penicillin-binding proteins threatens cephalosporin efficacy, while carbapenems and quinolones remain largely effective.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Antimicrobial Resistance

Background:

  • Haemophilus influenzae is a significant global pathogen causing severe illness and death.
  • Type b strains cause meningitis and bacteremia in unvaccinated populations.
  • Nontypeable strains are linked to respiratory and ear infections.

Purpose of the Study:

  • To review the diverse and widespread antibiotic resistance in Haemophilus influenzae.
  • To highlight emerging resistance mechanisms affecting common antibiotics.
  • To assess the current and future therapeutic options against this pathogen.

Main Methods:

  • Review of intrinsic efflux resistance mechanisms.
  • Analysis of beta-lactamase production prevalence and impact.
  • Examination of penicillin-binding protein alterations and their resistance patterns.
  • Assessment of carbapenem and quinolone susceptibility.
  • Evaluation of pharmacokinetic and pharmacodynamic factors for oral agents.

Main Results:

  • Intrinsic efflux limits macrolide, azalide, and ketolide activity.
  • High prevalence of beta-lactamase production confers resistance to ampicillin and amoxicillin.
  • Increasing penicillin-binding protein alterations (especially PBP3) drive resistance to ampicillin, amoxicillin-clavulanate, and cephalosporins.
  • Carbapenems and quinolones generally maintain activity.
  • Oral agent efficacy is influenced by pharmacokinetics.

Conclusions:

  • Antibiotic resistance in Haemophilus influenzae is more complex than commonly perceived.
  • Emerging resistance mechanisms necessitate careful antibiotic selection.
  • Carbapenems and quinolones represent reliable options, but pharmacokinetic limitations exist for oral therapies.

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