Resistance to penicillin and other antimicrobials in 103 clinical isolations of Streptococcus pneumoniae (2000-2001)

Abstract

Background. To determine in our hospital the sensitivity of isolations of Streptococcus pneumoniae to penicillin, as well as to analyse the association of resistance to penicillin and other antimicrobials and the activity of cefotaxime and cefepime in pencillin resistant strains of Streptococcus pneumoniae. Methods. The sensitivity was determined on 103 isolations of Streptococcus pneumoniae, from clinical samples from the years 2000-2001, to penicillin, eritromycine, cloramfenicol, tetracycline, cotrimoxazol, cefotaxime, cefepime and levofloxacine. Results. Sixty-eight percent of the isolations were sensitive to penicillin, while some 32% of the isolated strains of Streptococcus pneumoniae were penicillin resistant, with 7.7% showing a high degree of resistance. Resistance to eritromycine, cloramfenicol, tetracycline, cotrimoxazol and levofloxacine was 38.8%; 9.7%; 20.4%; 25.2% and 2.9% respectively, increasing to values of 66.6%; 30.3%; 48.5%; 72.7% and 9.1% in the 33 penicillin resistant strains. Resistance to cefotaxime and cefepime was 9.7% and 10.6% respectively. Conclusions. A high percentage of strains of Streptococcus pneumoniae show some degree of resistance to penicillin, but with lower figures than in other studies carried out at a national level. Similarly, it was demonstrated that resistance to penicillin is significantly associated (p < 0.001) with resistance to all the antimicrobials studied, except for levofloxacine. The resistances to cefotaxime and cefepime were comparable, with less activity being observed in these when facing penicillin resistant strains of Streptococcus pneumoniae.