[Haemophilus influenzae infections in infants and macrolides. Importance of the choice of an effective antibiotic and compliance with its administration schedule].

Five cases of meningitis due to Haemophilus influenzae type b are reported. In four, the same pathogen was recovered from blood. In every case, meningitis developed despite administration of macrolides for ENT infections (4 cases) or pneumonia (1 case). These five observations are conclusive evidence that macrolides failed to prevent meningeal diffusion of Haemophilus influenzae presumptively responsible for the initial focal infection. In vitro activity of macrolides against Haemophilus influenzae is poor. For the treatment of ENT infections in pediatric patients aged 2 months to 5 years, the age group most susceptible to infection by Haemophilus influenzae, we recommend amoxicillin which is more active and bactericidal. An adequate dosage should be used (50 to 100 mg/kg/24 h) divided into four oral doses given at six hour intervals. This therapeutic attitude may need to be revised if the prevalence of beta-lactamase-producing H. influenzae strains (5 to 10% as of now) were to increase. In this case, use of an amoxicillin-clavulanic acid combination under the same conditions as outlined above may prove satisfactory. Correct administration of judiciously chosen antibiotics in ENT infections in infants and children is the most effective means of preventing meningitis due to H. influenzae.