ABSTRACT
Penicillin is the drug of choice for the prevention of bacterial endocarditis (BE) resulting from dental treatment. The susceptibility of Streptococcus viridans to this antimicrobial agent was studied. A representative sample of hospital personnel (N = 76) was compared to a control group of seventy-six subjects who were not associated with the hospital. Twenty-four of the hospital personnel worked in wards that consume 0.13 to 1.64 (mean +/- SD = 0.88 +/- 0.64) gm penicillin per day per position (low consumption group = LCG) and fifty-two worked in wards that consume 2.27 to 3.67 (mean +/- SD = 3.04 +/- 0.55) gm penicillin per day per position (high consumption group = HCG). Antibiograms of oral isolates showed that, while 48.08% of the subjects from the HCG revealed penicillin-resistant S. viridans only 8.33% of the subjects from the LCG and 7.89% of the control group presented such results. The data presented suggest that there are subjects who may unknowingly carry penicillin-resistant S. viridans as part of their oral flora. It is therefore recommended that the preferable antibiotic used for the prevention of BE should be determined by an antibiogram.