Abstract
A simple, inexpensive method for screening for beta-lactamase-positive and beta-lactamase-negative ampicillin-resistant Haemophilus influenzae isolates was developed. Disks containing 10 micrograms of cloxacillin yielded no zone of inhibition when placed on chocolate agar plates inoculated with beta-lactamase-positive (16 strains) or ampicillin-resistant (greater than or equal to 1 microgram/ml) beta-lactamase-negative (10 strains) H. influenzae, whereas ampicillin-susceptible (less than or equal to 0.5 microgram/ml; 36 strains) H. influenzae almost always (92%) showed a zone of inhibition.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Bell S. M., Plowman D. Mechanisms of ampicillin resistance in Haemophilus influenzae from respiratory tract. Lancet. 1980 Feb 9;1(8163):279–280. doi: 10.1016/s0140-6736(80)90778-3. [DOI] [PubMed] [Google Scholar]
- Kilian M. A rapid method for the differentiation of Haemophilus strains. The porphyrin test;. Acta Pathol Microbiol Scand B Microbiol Immunol. 1974 Dec;82(6):835–842. doi: 10.1111/j.1699-0463.1974.tb02381.x. [DOI] [PubMed] [Google Scholar]
- Lerman S. J., Brunken J. M., Bollinger M. Prevalence of ampicillin-resistant strains of Haemophilus influenzae causing systemic infection. Antimicrob Agents Chemother. 1980 Sep;18(3):474–475. doi: 10.1128/aac.18.3.474. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Markowitz S. M. Isolation of an ampicillin-resistant, non-beta-lactamase-producing strain of Haemophilus influenzae. Antimicrob Agents Chemother. 1980 Jan;17(1):80–83. doi: 10.1128/aac.17.1.80. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Montgomery K., Raymundo L., Jr, Drew W. L. Chromogenic cephalosporin spot test to detect beta-lactamase in clinically significant bacteria. J Clin Microbiol. 1979 Feb;9(2):205–207. doi: 10.1128/jcm.9.2.205-207.1979. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Nelson J. D. The increasing frequency of beta-lactamase-producing Haemophilus influenzae B. JAMA. 1980 Jul 18;244(3):239–239. [PubMed] [Google Scholar]
- O'Callaghan C. H., Morris A., Kirby S. M., Shingler A. H. Novel method for detection of beta-lactamases by using a chromogenic cephalosporin substrate. Antimicrob Agents Chemother. 1972 Apr;1(4):283–288. doi: 10.1128/aac.1.4.283. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Offit P. A., Campos J. M., Plotkin S. A. Ampicillin-resistant, beta-lactamase-negative haemophilus influenzae type b. Pediatrics. 1982 Feb;69(2):230–232. [PubMed] [Google Scholar]
- Scheifele D. W. Ampicillin-resistant Hemophilus influenzae in Canada: nationwide survey of hospital laboratories. Can Med Assoc J. 1979 Jul 21;121(2):198–202. [PMC free article] [PubMed] [Google Scholar]
- Schwartz R., Rodriguez W., Khan W., Ross S. The increasing incidence of Ampicillin-resistant Haemophilus influenzae. A cause of otitis media. JAMA. 1978 Jan 23;239(4):320–323. [PubMed] [Google Scholar]
- Syriopoulou V., Scheifele D., Smith A. L., Perry P. M., Howie V. Increasing incidence of ampicillin resistance in Hemophilus influenzae. J Pediatr. 1978 Jun;92(6):889–892. doi: 10.1016/s0022-3476(78)80354-0. [DOI] [PubMed] [Google Scholar]
- Thornsberry C., Kirven L. A. Ampicillin resistance in Haemophilus influenzae as determined by a rapid test for beta-lactamase production. Antimicrob Agents Chemother. 1974 Nov;6(5):653–654. doi: 10.1128/aac.6.5.653. [DOI] [PMC free article] [PubMed] [Google Scholar]