Antimicrobial resistance patterns of Haemophilus influenzae isolated from patients with meningitis in São Paulo, Brazil.
From 1989 to 1995, a total of 391 Haemophilus influenzae isolates were recovered from the cerebrospinal fluid (CSF) of hospitalized patients in São Paulo, Brazil. The majority of strains were isolated from infants aged less than 5 years. Strains belonging to biotype I (64.7%), biotype II (34.5%) and biotype IV (0.76%) were detected. Ninety-nine percent of these strains were serotype b. Minimal inhibitory concentration (MIC) was determined for ampicillin, chloramphenicol and ceftriaxone. The ss-lactamase assay was performed for all strains. The rate of ss-lactamase producer strains ranged from 10 to 21.4% during a period of 7 years, with an overall rate of 13.8%. Of the 391 strains analyzed, none was ss-lactamase negative ampicillin resistant (BLNAR). A total of 9.7% of strains showed resistance to both ampicillin and chloramphenicol; however, 4% of them were resistant to ampicillin only and 2% to chloramphenicol. All strains were susceptible to ceftriaxone and the MIC90 was 0.007 microg/ml, suggesting that ceftriaxone could be an option for the treatment of bacterial meningitis in pediatric patients who have not been screened for drug sensitivity.
Casagrande
S T
ST
Seção de Bacteriologia, Instituto Adolfo Lutz, São Paulo, SP, Brasil. casail@unisys.com.br
Vicente
E J
EJ
Landgraf
I M
IM
Kobata
A M
AM
D000667:Ampicillin / Q000494:pharmacology / Q000627:therapeutic use; D000900:Anti-Bacterial Agents / Q000494:pharmacology* / Q000627:therapeutic use; D001938:Brazil; D002443:Ceftriaxone / Q000494:pharmacology / Q000627:therapeutic use; D002648:Child; D002675:Child, Preschool; D002701:Chloramphenicol / Q000494:pharmacology / Q000627:therapeutic use; D004352:Drug Resistance, Microbial; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000302:isolation & purification / Q000378:metabolism; D006801:Humans; D008583:Meningitis, Haemophilus / Q000382:microbiology*; D008826:Microbial Sensitivity Tests; D001618:beta-Lactamases / Q000096:biosynthesis
D000900:Anti-Bacterial Agents; D002701:Chloramphenicol; D002443:Ceftriaxone; D000667:Ampicillin; D001618:beta-Lactamases