[Multiresistant Escherichia coli from elderly patients].
We examined all ceftriaxone-resistant Escherichia coli isolates obtained from clinical samples during 16 months (1 Dec. '97-31 Mar. '99). A total of 97 resistant isolates from 36 patients were obtained, mostly from urine specimens. Of these patients, 35/36 were over 75 years old, most lived in nursing homes, were dependent on nursing in their daily lives, and were incontinent and/or had indwelling catheters. All 97 isolates had similar susceptibility profiles: resistant to ciprofloxacin, gentamicin, ampicillin, amoxycillin/clavulanate, tricarcillin/clavulanate, aztreonam, and cefuroxime; decreased susceptibility to ceftazidime and cefepime; and susceptible to imipenem and meropenem. Double-disc tests indicated that all strains produced extended spectrum beta-lactamase(s). All the isolates belonged to 1 of 3 E. coli serotypes: 79 were 0153:H31, 13 were 0142:H10, and 5 were 0102:H6.