Surveillance data collected by the World Health Organization implicate Haemophilus influenzae as a major cause of death and disability among young children around the world. The development of an effective vaccine in 1988 virtually eradicated the disease in the United States, however cases still occur among children who were never immunized, children who do not receive all doses as well as adults and older children with certain kinds of immune system problems. H. influenzae responds to four different classes of antibiotics.
Pencillins
Penicillin-derivative ampicillin treats invasive and non-invasive H. influenza. Intravenous ampicillin is administered with a second drug, chloramphenicol while oral ampicillin achieves optimal results when paired with clavulanic acid. Ampicillin is effective, inexpensive, and generally well-tolerated, however widespread use has contributed to the emergence of drug resistant strains, particularly in Europe, Japan and developing countries. According to Dr. Timothy F. Murphy, ampicillin-resistant strains account for a small number of U.S. infections, however drug-resistant strains elsewhere put the U.S. at risk.
Cephalosporins
Cephalosporins operate by a mechanism similar to penicillins. The third-generation cephalosporins ceftriaxone and cefotaxime combat invasive infections due to Hemophilus influenza. Non-invasive infections respond to several oral cephalosporins. Unfortunately, resistance to one cephalosporin usually means resistance to all and the drugs are contraindicated in penicillin-allergic patients due to the potential for cross-reactivity.
Macrolides
Health care providers choose macrolides including azithromycin, clarithromycin and the related drug, telithromycin for penicillin- and cephalosporin-allergic patients with H. influenza infections. However, according to Dr. Henry F. Chambers and pharmacist Daniel H. Deck in their book "Lange's Basic and Clinical Pharmacology," patients usually complain of significant gastrointestinal side-effects such as lack of appetite, nausea, vomiting and diarrhea. Since H. influenza also requires a prolonged---one to two week---course of treatment, many patients fail to complete therapy.
Fluoroquinolones
Fluoroquinolones such as ciprofloxacin and moxifloxacin administered orally or intravenously are highly effective against both typable and non-typable H. influenza strains. In addition, they are extremely well-tolerated, but offer drawbacks such as relatively high cost and increasing resistance. Pregnant women and children should not receive fluoroquinolones due to the potential for severe side effects such as birth defects and tendon rupture.
References
- WHO: Haemophilus Influenzae Type B (HiB)
- CDC: Haemophilus Influenzae Type B and HiB Infections: Epidemiology and Prevention of Vaccine Preventable Diseases
- Haemophilus Influenza (Chapter); T.F. Murphy; In: Harrison's Principles of Internal Medicine, 17th edition; A.S. Fauci, E. Braunwald, D.L. Kasper, S.L. Hauser, D.L. Longer, J.L. Jameson and J. Loscalzo; 2008
- Chemotherapeutic Drugs (Chapter); H.F. Chambers and D.H. Deck; In: "Basic and Clinical Pharmacology, 11th edition;" B.G. Katzung, S.B. Masters and A.J. Trevor (Eds.); 2009
- CDC: Vaccines and Preventable Diseases: HiB In Short
