GEOGRAPHIC-DISTRIBUTION OF PENICILLIN RESISTANCE OF STREPTOCOCCUS-PNEUMONIAE IN BRAZIL - GENETIC RELATEDNESS

From January 1993 through December 1996, 1,252 Streptococcus pneumonia e strains from different geographic regions of Brazil were studied for penicillin (Pen) susceptibility. All pneumococci were isolated from n ormally sterile fluids from patients, newborns to 88 years old. Pen re sistance (R) had a mean rate of 15.1%, with 14.5% of strains showing i ntermediate level Pen-R and 0.6% showing high-level Pen-R, Similar Pen -R rates were observed in different regions of the country, in the ran ge of 9.5% to 17.1%. A Pen-R increase was noted from 9.6% in 1993 to 2 0.6% in 1996. Pen-R was mostly associated to serotypes 6B, 14, 19A, an d 23F (89%), Chromosomal DNA relatedness of Pen-R strains was determin ed by pulsed field gel electrophoresis (PFGE), High genetic diversity was identified, being represented by 27 patterns among the 92 strains. Two important features were observed: the predominance of relatively low-level Pen MIC (range 0.1-0.5 mg/L) in 86 of the 92 strains, and th e presence of 60.8% as four major PFGF clusters unique to Brazil. Anot her feature was the geographic spread of these clusters over large dis tances in the country. The city of Sao Paulo seems to be a Pen-R focus (18.4%) in Brazil. Only two strains representing the international cl one B widely spread in France, Portugal, and Spain, belonging to serot ype 14, were found.