title: [Clinical significance of bacterial beta-lactamase production in the treatment of urinary tract infections with oral beta-lactam-antibiotics].
abstract: In 649 urological patients with urinary tract infections (UTI) a total of 1114 bacterial strains were isolated and their beta-lactamase production was investigated by a qualitative, micro-iodometric method. Approximately 40% of all strains, 33% of E. coli species and 8% of Proteus mirabilis species were enzyme producers. All of the isolates of E. coli and Proteus mirabilis defined as non-producers were sensitive to ampicillin and cephalothin in the agar diffusion test. The beta-lactamase producers of these two species did not show the same pattern: almost all of them were ampicillin-resistant, but most were cephalothin-sensitive. The other species were all found to be either producers or non-producers. Therapeutic comparisons in altogether 138 UTI patients treated with ampicillin or cephalexin, two antibiotics with different beta-lactamase stability, confirmed the positive correlation between enzyme production and therapeutic failure in both groups. Cephalexin, however, tended to be more effective than ampicillin against enzyme-producing species.
mesh_terms: D000284:Administration, Oral; D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D004755:Enterobacteriaceae / Q000187:drug effects / Q000201:enzymology*; D005260:Female; D006801:Humans; D008297:Male; D014552:Urinary Tract Infections / Q000188:drug therapy* / Q000201:enzymology; D001618:beta-Lactamases / Q000096:biosynthesis*; D047090:beta-Lactams
chemical_list: D000900:Anti-Bacterial Agents; D047090:beta-Lactams; D001618:beta-Lactamases
vernacular_title: Klinische Bedeutung der beta-Lactamase-Produktion von Bakterien bei der Therapie der Harnwegsinfektionen mit oralen beta-Lactam-Antibiotika.