Antibiotic susceptibility of important bacterial respiratory pathogens in northeastern Germany

Background: There is still a lack of comprehensive study results about resistance of bacterial respiratory pathogens from the east of the Federal Republic of Germany. Methods: In Greifswald we isolated in 1995 and 1996 320 strains of typical pathogens and tested their susceptibility to 14 antibiotics, using the microbouillon dilution method. Results: Pneumococci and beta-haemolytic streptococci were completely susceptible to penicillin and al other beta-lactam-antibiotics, clindamycin and vancomycin. 4,8% of pneumococci and 10,0% of Streptococcus pyogenes isolates were resistant to erythromycin. This should lead to a more differentiated use of macrolides as concerns these pathogens, especially as penicillin still has high efficacy in these cases. Pneumococci had resistance rates of 4,8%, 9,5% and 6,7% to cotrimoxazole, tetracycline and ofloxacin, respectively. No strain of Haemophilus influenzae produced a beta-lactamase. 2,6% of strains were relatively resistant to ampicillin, even in combination with sulbactam. Cefaclor, erythromycin and tetracycline had restricted efficacy of 16,7%, 14,1% and 53,8%, respectively. Cefuroxime, cefixime, cefepime, imipenem and ofloxacin al had complete efficacy. 77,8% of Moraxella catarrhalis isolates were beta-lactamase positive. Strains were susceptible to erythromycin, ofloxacin and all tested beta-lactam-antibiotics except ampicillin and cefaclor. There was a relative resistance to clindamycin and tetracyclin of 22,2% and 2,2% respectively. Discussion: We present our results in national and international comparison, describe tendencies of resistance, give reasons for the low incidence of penicillin resistance in pneumococci in Germany and draw conclusions for empirical chemotherapy.