Is Helicobacter pylori antibiotic resistance surveillance needed and how can it be delivered?

BACKGROUND: Most patients are prescribed Helicobacter pylori treatment without culture and antibiotic susceptibility testing, as current guidance recommends that patients with recurrent dyspepsia should be tested for H. pylori using a non-invasive breath or faecal antigen test. AIMS: To determine the prevalence of H. pylori antibiotic resistance in patients attending endoscopy in England and Wales, and the feasibility of an antibiotic resistance surveillance programme testing. METHODS: We tested the antibiotic susceptibility of H. pylori isolates from biopsy specimens from 2063 of 7791 (26%) patients attending for endoscopy in Gloucester and Bangor, and 339 biopsy specimens sent to the Helicobacter Reference Unit (HRU) in London. Culture and susceptibility testing was undertaken in line with National and European methods. RESULTS: Helicobacter pylori were cultured in 6.4% of 2063 patients attending Gloucester and Bangor hospitals. Resistance to amoxicillin, tetracycline and rifampicin/rifabutin was below 3% at all centres. Clarithromycin, metronidazole and quinolone resistance was significantly higher in HRU (68%, 88%, 17%) and Bangor isolates (18%, 43%, 13%) than Gloucester (3%, 22%, 1%). Each previous course of these antibiotics is associated with an increase in the risk of antibiotic resistance to that agent [clarithromycin: RR = 1.5 (P = 0.12); metronidazole RR = 1.6 (P = 0.002); quinolone RR = 1.8 (P = 0.01)]. CONCLUSIONS: Helicobacter pylori infection is now uncommon in dyspeptic patients at endoscopy. A surveillance system is feasible and necessary to inform dyspepsia management guidance. Clinicians should take a thorough antibiotic history before prescribing metronidazole, clarithromycin or levofloxacin for H. pylori.

Improving blood-borne viral diagnosis; clinical audit of the uptake of dried blood spot testing offered by a substance misuse service.

SUMMARY: The diagnosis of blood-borne viral infection amongst drug injectors in Wales is limited by a poor uptake of diagnostic testing; recent research suggests that dried blood spot (DBS) sample collection, rather than venepuncture, may improve diagnostic rates. We carried out an audit of the uptake of DBS testing for hepatitis C, hepatitis B and HIV amongst drug injectors attending a substance misuse service (SMS) in the first year of DBS testing being routinely offered to clients (1 May 2007 to 30 April 2008) and compared the uptake to venepuncture testing of SMS clients in the previous year. Uptake of DBS testing for hepatitis C, hepatitis B and HIV was almost six times greater than the uptake of venepuncture testing amongst clients of the SMS in the previous year. The data are consistent with the hypothesis that DBS testing can increase the uptake of blood-borne viral testing amongst current and ex-drug injectors. We accept that part of the almost sixfold increase in diagnostic testing observed in the first year of DBS testing may be due to an increase in awareness amongst drug injectors of testing opportunities and a prioritization of testing by the SMS. Nonetheless the dramatic increase in uptake demonstrates that DBS testing is acceptable to drug injectors and should be subject to more rigorous trials to evaluate its potential impact on diagnosis.

Analysis of 42 cases of septicemia caused by an epidemic strain of methicillin-resistant Staphylococcus aureus: evidence of resistance to vancomycin.

Recent case reports of vancomycin treatment failures in the United States, Japan, and France have prompted a retrospective analysis of 42 cases of septicemia caused by epidemic methicillin-resistant Staphylococcus aureus strain 15 (EMRSA-15), which is the most prevalent epidemic strain of methicillin-resistant S. aureus in the United Kingdom; all cases occurred in a teaching hospital in Manchester, United Kingdom, between 1994 and 1998. Mortality was lowest (4%) in patients with rifampin-susceptible isolates treated with vancomycin and rifampin. It rose to 38% in patients who were treated with both antibiotics but in whom the organism became resistant to rifampin during therapy, and it reached 78% in patients who had rifampin-resistant isolates or in whom rifampin was contraindicated (P<.0001; Fisher exact test, 2-tailed). All isolates were susceptible to vancomycin by conventional laboratory testing, but susceptibility was lost by growth in vancomycin in vitro, becoming resistant at a minimum inhibitory concentration of 8 mg/L. This was associated with accumulation of cell-wall material. The deoxyribonucleic acid fingerprint remained unchanged. This study suggests that rifampin played a key role in the prevention of deaths caused by an epidemic strain of methicillin-resistant S. aureus that readily gave rise to a subpopulation with reduced susceptibility to vancomycin.

Removal of the subchondral plate in acetabular preparation.

Retention of the subchondral plate during acetabular preparation in total hip replacement is believed to be an important part of modern cementing techniques. We have constructed a two-dimensional finite element analysis to assess the effect of retention and removal of this relatively stiff structure. The finite element analysis demonstrates increased stiffness and stress concentrations at the bone-cement interface that may have an adverse effect. Although further study is required, it may be that subchondral bone retention is not advantageous.

Abductor weakness and stresses around acetabular components of total hip arthroplasty: a finite element analysis.

Abductor weakness, and the resulting Trendelenburg gait, after total hip arthroplasty is believed to be associated with a poor long-term outcome. We have constructed a two-dimensional finite element analysis using load cases to mimic this abductor weakness. The finite element analysis demonstrates slightly increased stresses, particularly at the bone-cement interface in the DeLee-Charnley zone I, which does not seem sufficient to explain the adverse effect of abductor weakness.

Therapeutic efficacy and complications of excisional biopsy of condyloma acuminatum.

BACKGROUND AND OBJECTIVES: Among the various treatment modalities for condyloma acuminatum, excisional cold-blade surgery appears excellent but it has been little studied and little used, particularly for lesions not located in the perianal area. GOALS: To examine the efficacy and complications of scissors excision of single anogenital warts. STUDY DESIGN: Retrospective analysis of single warts completely excised with scissors for the purpose of biopsy before patient entry in a randomized, placebo-controlled study of the efficacy and safety of various parenteral interferons in combination with cryotherapy. RESULTS: Of 152 patients entered in the main study, 85 patients were available for analysis. At 4 and 16 weeks after excision, 16 of 85 (19%) and 14 of 68 (21%) of the excised lesions recurred. After at 6 least months of follow-up, 2 of 11 (18%) of the excision sites demonstrated some evidence of pigmentation changes. CONCLUSIONS: Scissors excision of single anogenital warts has a high rate of success and acceptable long-term side-effects.

Preliminary investigation into the purification, NMR analysis, and molecular modelling of chondroitin sulphate epitopes.

Electrophoretic methods are outlined for the rapid purification and analysis of chondroitin sulphate oligosaccharides on a milligram scale. Isomeric impurities however, exist within specific sized oligosaccharides. Detailed 1H and 13C NMR data for the chondroitin sulphate disaccharides delta 4HexA(1-3)GalNAc6SO3- and delta 4HexA(1-3)GalNAc4SO3- (prepared from shark chondroitin sulphate) are reported. Two-dimensional NMR methods have been employed in the assignment of spectra. Preliminary models of these disaccharides are proposed from molecular mechanics conformational searching and molecular dynamics procedures. This study provides 1H and 13C NMR reference data which will be useful in the investigation of larger chondroitin sulphate oligosaccharides, such as those prepared by the electrophoretic methods mentioned above.

Structural characterization of neutral oligosaccharides with blood-group A and H activity isolated from bovine submaxillary mucin.

In this study we investigated the structures of 11 neutral oligosaccharides released from bovine submaxillary mucin by alkaline borohydride treatment and isolated by h.p.l.c. One hexa-, one penta-, three tetra-, four tri- and two di-saccharides containing core types 1, 2, 3 or 4 were obtained. We report their structures, determined by a combination of one- and two-dimensional 1H n.m.r. spectroscopy at 270 MHz and methylation analysis involving g.l.c.-m.s., along with their approximate molar ratios. Only three of these oligosaccharides have previously been reported in this source. Of the new oligosaccharides, one contains the blood-group-A antigenic determinant, two contain the blood-group-H type 2 determinant, while another contains the blood-group-H type 3 determinant. The oligosaccharide GlcNAc beta (1----6)[GlcNAc beta (1----3)]GalNAcol, although previously found as a core structure, has been isolated here as a novel trisaccharide.

Structure determination of five sialylated trisaccharides with core types 1, 3 or 5 isolated from bovine submaxillary mucin.

In this study we have investigated the structures of five sialylated trisaccharides released from bovine submaxillary mucin by alkaline borohydride treatment and isolated by high-performance liquid chromatography. Three of the trisaccharides contained NeuAc while two contained NeuGc. One oligosaccharide contained core-type 1, two contained core-type 3 and two contained core-type 5. The structures, determined by a combination of one- and two-dimensional 1H-NMR spectroscopy at 270 MHz and methylation analysis involving gas-liquid chromatography/mass spectrometry, were as follows: A4b, GalNAc alpha(1----3) [NeuAc alpha(2----6)]GalNAcol; A4c, GlcNAc beta(1----3)[NeuAc alpha(2----6)]GalNAcol; A4d, Gal beta(1----3)[NeuAc alpha(2----6)]GalNAcol; A4e, GalNAc alpha(1----3)-[NeuGc alpha(2----6)]GalNAcol; A4f, GlcNAc beta(1----3)[NeuGc alpha (2----6)]GalNAcol. The oligosaccharides occurred in the approximate molar ratios 1.0:12.0:0.3:0.2:2.0. This is the first report of oligosaccharides containing core-type 5 and of the occurrence of oligosaccharides A4b, A4e, and A4f in bovine submaxillary mucin. 1H-NMR data for structure A4e, which is a novel structure, are presented for the first time.

Determination of the structure of a novel acidic oligosaccharide with blood-group activity isolated from bovine submaxillary-gland mucin.

In this study we investigated the structure of an acidic fucose-containing pentasaccharide released from bovine submaxillary-gland mucin by alkaline-borohydride treatment. The structure, determined by a combination of one-dimensional and two-dimensional 1H-n.m.r. spectroscopy at 270 MHz and methylation analysis involving g.l.c.-m.s., was as follows: Fuc alpha(1----2)Gal beta(1----4)GlcNAc beta(1----3)[NeuAc alpha(2----6)]GalNAcol This pentasaccharide is a novel structure and is the first report of a blood-group-H type 2 determinant on a submaxillary-gland mucin.