The comparative in-vitro activity of roxithromycin and other antibiotics against Bordetella pertussis

Abstract

In spite of vaccination programmes, whooping cough epidemics continue to occur. The disease affects all age groups, although its severity is greatest in the young, with infants being particularly vulnerable. Erythromycin is generally accepted as the drug of choice both for treatment and for prophylaxis during epidemics. Roxithromycin is a macrolide with pharmacokinetic advantages over erythromycin; it is well absorbed, produces high serum concentrations, has a long half-life and penetrates respiratory secretions well. There are no accepted standards for testing the sensitivity of Bordetella pertussis to antibiotics, and reports of the activity of roxithromycin and erythromycin are variable. Using Isosensitest agar supplemented with 5% horse blood and an inoculum of 10(4) cfu, 88 strains of B. pertussis were tested for their sensitivity to roxithromycin, erythromycin, rifampicin and trimethoprim/sulphamethoxazole. The range of MICs was 0.12-0.5 mg/L for both roxithromycin and erythromycin. Roxithromycin was bactericidal, with an MBC of 1 mg/L (as compared with 0.5 mg/L for erythromycin). Since roxithromycin is well tolerated by children when used for respiratory tract infections, the good in-vitro activity against B. pertussis, combined with its favourable pharmacokinetics, suggest it may be a good candidate for use in the treatment and prophylaxis of whooping cough.

Quimioprofilaxis en coqueluche: ¿Sacar agua a canastos?

“…Ensayos bien reglados han establecido la negativización del cultivo en 5 días de tratamiento con macrólidos 48 . No se dispone de información acabada respecto al efecto erradicador que tendrían cotrimoxazol 38,49,50 y las cefalosporinas de tercera generación, si bien todos estos antimicrobianos son activos in vitro sobre B. pertussis 49,51,52 .…”

Pertussis: A Continuing Hazard for Healthcare Facilities

“…72 B pertussis is susceptible in vitro to trimethoprim-sulfamethoxazole, 71,72 the newer macrolides azithromycin and clarithromcyin, 70,72 and the quinolones levofloxacin, ciprofloxacin, ofloxacin, and gatifloxacin. 72 Trimethoprim-sulfamethoxazole has been demonstrated to be effective in small clinical trials 84 and therefore is the recommended alternative for treatment or prophylaxis of individuals intolerant to erythromycin 73,76 ; however, its efficacy as a chemoprophylactic agent has not been evaluated.…”