title: Occurrence and transfer of ampicillin resistance associated with ampicillin-resistant Haemophilus influenzae isolated from a case at a day-care centre.
abstract: A 1-year-old boy with recurrent otitis media had been repeatedly treated with antibiotics. A few days after withdrawal of administered ampicillin he again contracted otitis media and ampicillin-resistant Haemophilus influenzae was isolated. The strain was serologically untypable. No ampicillin-resistant H. influenzae was found in his family or at the day-care centre that he attended. The ability to produce the beta-lactamase elaborated from this strain could be transferred to ampicillin-sensitive strains of H. influenzae and Escherichia coli in frequencies of 0.7 X 10(-7) and 4.1 X 10(-4) respectively. The transcipients obtained were ampicillin-resistant and beta-lactamase producing. In the transcipients of E. coli, however, the marker for ampicillin resistance was quite unstable.
mesh_terms: D000581:Amidohydrolases / Q000096:biosynthesis; D000667:Ampicillin / Q000494:pharmacology*; D002648:Child; D002675:Child, Preschool; D004926:Escherichia coli / Q000187:drug effects; D006192:Haemophilus Infections / Q000382:microbiology*; D006193:Haemophilus influenzae / Q000187:drug effects* / Q000302:isolation & purification; D006801:Humans; D007223:Infant; D008297:Male; D010033:Otitis Media / Q000382:microbiology*; D010403:Penicillin Resistance; D012008:Recurrence
chemical_list: D000667:Ampicillin; D000581:Amidohydrolases