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Louise Teare

Publications and source records attributed to Louise Teare.

5 recordsLinked to original sources
PubMed2002

Helicobacter pylori susceptibility testing by disc diffusion.

The bacterium Helicobacter pylori is found in c. 40% of the population and is responsible for the development of duodenal disease. Triple treatment with a proton-pump inhibitor or bismuth salt plus two antibiotics is now commonplace in all patients diagnosed. As antibiotic resistance reduces treatment efficacy, it is time to consider routine susceptibility testing to guide individual patient treatment and surveillance of antibiotic resistance. There are no published nationally agreed standards for disc diffusion testing of H. pylori. After reviewing the literature, we recommend the following method for disc diffusion tests. A suspension of cultures < or = 4 days old equivalent to McFarland Standard no. 4 (10(8) cfu/mL) should be used on Mueller-Hinton or Columbia agar base with 5-10% blood, using a metronidazole disc strength of 5 Ig and a clarithromycin disc strength of 2 microg. Anaerobic pre-incubation of plates is unnecessary. A H. pylori control susceptible to metronidazole (e.g. NCTC 12822) should be used. Zone sizes with the Mueller-Hinton agar base for metronidazole testing are <16 mm resistant, 16-21 mm intermediate and >21 mm susceptible. We suggest that isolates in the intermediate zone should be re-tested by Etest. Zone sizes with the Columbia agar base for metronidazole testing are <10 mm resistant and > or = 10 mm susceptible. Co-infection with two strains, which may be a mixture of isolates susceptible and resistant to metronidazole leading to conflicting susceptibility results, occurs in 5-10% of patients. Zone sizes with Mueller-Hinton agar and Columbia blood agar for clarithromycin testing are resistant no zone and susceptible any zone.

Anaerobiosis↗
PubMed2002

Linezolid-resistant enterococci: report of the first isolates in the United Kingdom.

Linezolid, the first oxazolidinone antibacterial agent to be developed for clinical use, was licensed in the UK in early 2001. We report the first three examples of resistant enterococci (two isolates of Enterococcus faecium and one Enterococcus faecalis) isolated in the UK, which were obtained from patients who had received linezolid. The linezolid MICs for the resistant isolates were 64 mg/L. Pulsed-field gel electrophoresis (PFGE) analysis of the linezolid-susceptible and -resistant isolates from two of the patients, combined with sequence analysis of rRNA, indicated that resistance developed in previously susceptible strains, most probably via a point mutation in the 23S rRNA.

Acetamides↗