[Phenotyping and antibiotic susceptibility's study of Neisseria meningitidis strains isolated at the "Hôpital d'Enfants" of Tunis].

A total of 23 invasive strains of Neisseria meningitidis were isolated between March 1998 and February 2004. 19 strains were recovered from cerebrospinal fluid (CSF) and 4 from blood. The majority of these strains were recovered from children with an age less to 4 years (86.9%). The antigenic formula'study (serogroup:serotype:serosubtype) of the strain's collection have shown there great diversity. The sero-group B was the most frequent (83%) followed by serogroup C (17%). The B:NT:NST phenotype was major among strains of the serogroup B and the C:4:P1-14 phenotype among strains of the serogroup C. No beta-lactamase activity was detected. 30.4% of the strains were of diminished susceptibility to penicillin G (CM190 = 0.38 Ig/ml). No resistance to amoxicillin (CMI90 = 0.19 microg/ml), to cefotaxime (CMI90 = 0.016 microg/ml) and to rifampin (CMI90-0.125 microg/ml) was detected; whereas 8.7% of strains-were resistant to chloramphenicol (CMI90=2 Ig/ml) and 65.2% to spiramycin.