Haemophilus influenzae: the current status of its in vitro susceptibility to antimicrobials

Continuous surveillance of the antimicrobial susceptibility patterns of strains of Haemophilus influenzae (H. i.) is part of a routine surveillance of bacterial sensitivity to antibiotics. In this study a major attention was given to the clinically important antimicrobials used in the treatments of H. i. infections, namely ampicillin, chloramphenicol and some cephalosporin preparations. Antimicrobial susceptibility determinations carried out in 1983 and before on H.i. strains isolated in different Czech regions show a clear-cut tendency towards the higher incidence of strains resistant to ampicillin and its derivative amoxycillin. The rise in resistance to erythromycin was also observed. Susceptibility to chloramphenicol continues to remain unchanged. Of the cephalosporin antimicrobials tested (cephalothin, ceftriaxone, cefaperazone, cefsulodine and cefadroxil) the most active were ceftriaxone and cefaperazone. The need of a further continuation of surveillance of H.i. drug susceptibility patterns is strongly emphasized; to ensure effective treatment results antibiograms should be done in each case of H.i. infection.