The In-vitro susceptibilities of toxigenic Corynebacterium diphtheriae isolated between 1992 and 1996 in Viet nam

The in-vitro activities of 12 antibiotics against 88 toxigenic strains of C.diphtheriae isolated from children with clinical diphtheria between 1992 and 19% were determined by agar dilution. All isolates were susceptible to penicillin, ampicillin, cefuroxime, ceftriaxone, ciprofloxacin and gentamicin. 27/88 (31%) isolates were resistant to one or more of the other antibiotics including tetracycline in 21/88 (24%), erythromycin and azithromycin in 13/88 (15%), chloramphenicol in 7/88 (8%), trimethoprim in 3/88 (3%) and rifampicin in 1/88(1%). 14/88 isolates were resistant to several antibiotics [TetREryR (7), TetRChlorR (2), TetREryR ChlorR (2) and TetRChlorRTrimRRifR (1)]. The emergence of resistance to multiple antibiotics in C.diphtheriae is of concern