Gentamicin, azithromycin and ceftriaxone in the treatment of gonorrhoea; the relationship between antibiotic minimum inhibitory concentration and clinical outcome

© Crown copyright 2019. OBJECTIVES: To investigate the relationship between MIC and clinical outcome in a randomized controlled trial that compared gentamicin 240 mg plus azithromycin 1 g with ceftriaxone 500 mg plus azithromycin 1 g. MIC analysis was performed on Neisseria gonorrhoeae isolates from all participants who were culture positive before they received treatment. METHODS: Viable gonococcal cultures were available from 279 participants, of whom 145 received ceftriaxone/azithromycin and 134 received gentamicin/azithromycin. Four participants (6 isolates) and 14 participants (17 isolates) did not clear infection in the ceftriaxone/azithromycin and gentamicin/azithromycin arms, respectively. MICs were determined by Etest on GC agar base with 1% Vitox. The geometric mean MICs of azithromycin, ceftriaxone and gentamicin were compared using logistic and linear regression according to treatment received and N. gonorrhoeae clearance. RESULTS: As the azithromycin MIC increased, gentamicin/azithromycin treatment was less effective than ceftriaxone/azithromycin at clearing N. gonorrhoeae. There was a higher geometric mean MIC of azithromycin for isolates from participants who had received gentamicin/azithromycin and did not clear infection compared with those who did clear infection [ratio 1.95 (95% CI 1.28-2.97)], but the use of categorical MIC breakpoints did not accurately predict the treatment response. The geometric mean MIC of azithromycin was higher in isolates from the pharynx compared with genital isolates. CONCLUSIONS: We found that categorical resistance to azithromycin or ceftriaxone in vitro, and higher gentamicin MICs in the absence of breakpoints, were poorly predictive of treatment failure

Gentamicin compared with ceftriaxone for the treatment of gonorrhoea (G-ToG): a randomised non-inferiority trial

© 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY-NC-ND 4.0 license. Background: Gonorrhoea is a common sexually transmitted infection for which ceftriaxone is the current first-line treatment, but antimicrobial resistance is emerging. The objective of this study was to assess the effectiveness of gentamicin as an alternative to ceftriaxone (both combined with azithromycin) for treatment of gonorrhoea. Methods: G-ToG was a multicentre, parallel-group, pragmatic, randomised, non-inferiority trial comparing treatment with gentamicin to treatment with ceftriaxone for patients with gonorrhoea. The patients, treating physician, and assessing physician were masked to treatment but the treating nurse was not. The trial took place at 14 sexual health clinics in England. Adults aged 16–70 years were eligible for participation if they had a diagnosis of uncomplicated genital, pharyngeal, or rectal gonorrhoea. Participants were randomly assigned to receive a single intramuscular dose of either gentamicin 240 mg (gentamicin group) or ceftriaxone 500 mg (ceftriaxone group). All participants also received a single 1 g dose of oral azithromycin. Randomisation (1:1) was stratified by clinic and performed using a secure web-based system. The primary outcome was clearance of Neisseria gonorrhoeae at all initially infected sites, defined as a negative nucleic acid amplification test 2 weeks post treatment. Primary outcome analyses included only participants who had follow-up data, irrespective of the baseline visit N gonorrhoeae test result. The margin used to establish non-inferiority was a lower confidence limit of 5% for the risk difference. This trial is registered with ISRCTN, number ISRCTN51783227. Findings: Of 1762 patients assessed, we enrolled 720 participants between Oct 7, 2014, and Nov 14, 2016, and randomly assigned 358 to gentamicin and 362 to ceftriaxone. Primary outcome data were available for 306 (85%) of 362 participants allocated to ceftriaxone and 292 (82%) of 358 participants allocated to gentamicin. At 2 weeks after treatment, infection had cleared for 299 (98%) of 306 participants in the ceftriaxone group compared with 267 (91%) of 292 participants in the gentamicin group (adjusted risk difference −6·4%, 95% CI −10·4% to −2·4%). Of the 328 participants who had a genital infection, 151 (98%) of 154 in the ceftriaxone group and 163 (94%) of 174 in the gentamicin group had clearance at follow-up (adjusted risk difference −4·4%, −8·7 to 0). For participants with a pharyngeal infection, a greater proportion receiving ceftriaxone had clearance at follow-up (108 [96%] in the ceftriaxone group compared with 82 [80%] in the gentamicin group; adjusted risk difference −15·3%, −24·0 to −6·5). Similarly, a greater proportion of participants with rectal infection in the ceftriaxone group had clearance (134 [98%] in the ceftriaxone group compared with 107 [90%] in the gentamicin group; adjusted risk difference −7·8%, −13·6 to −2·0). Thus, we did not find that a single dose of gentamicin 240 mg was non-inferior to a single dose of ceftriaxone 500 mg for the treatment of gonorrhoea, when both drugs were combined with a 1 g dose of oral azithromycin. The side-effect profiles were similar between groups, although severity of pain at the injection site was higher for gentamicin (mean visual analogue pain score 36 of 100 in the gentamicin group vs 21 of 100 in the ceftriaxone group). Interpretation: Gentamicin is not appropriate as first-line treatment for gonorrhoea but remains potentially useful for patients with isolated genital infection, or for patients who are allergic or intolerant to ceftriaxone, or harbour a ceftriaxone-resistant isolate. Further research is required to identify and test new alternatives to ceftriaxone for the treatment of gonorrhoea. Funding: UK National Institute for Health Research

Regulation of mitogen-activated protein kinases by Group 1 metabotropic glutamate receptors

EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Regulation of Mitogen-activated protein kinases by Group I metabotropic glutamate receptors

The regulation of mitogen-activated protein kinase (MAPK) activities by the group I metabotropic glutamate (mGlu) receptors, mGlu1a and mGlu5a, has been studied in Chinese hamster ovary (CHO) cells, where receptor expression is under inducible control. Both mGlu receptors stimulated comparable, robust and transient increases in the activity of the extracellular signal-regulated kinase (ERK) subgroup. Further, the mGlu1a, but not the mGlu5a receptor was found to mediate an increase in the activity of c-Jun N-terminal kinase (JNK). Examination of the signalling profile of mGlu1/mGlu5a receptor-mediated ERK activation revealed clear differences in the G-protein subpopulations involved, with only mGlu1a receptor-mediated ERK responses attenuated by pertussis toxin (PTx) pre-treatment. Both mGlu1a and mGlu5a receptor-mediated ERK activation occurred via mechanisms dependent on the non-receptor tyrosine kinase, Src, but independent of phosphoinositide 3-kinase activity, PKC and intracellular and/or extracellular Ca2+ concentration. Data also demonstrate a requirement for PDGF receptor tyrosine kinase activity in ERK activation by the mGlu1a, but not the mGlu4a receptor. The mGlu1a receptor-mediated JNK response, unlike ERK activation by the same receptor, was insensitive to PTx pre-treatment and occurred via mechanisms independent of intracellular and/or extracellular Ca2+ concentration, Src kinase and was unaffected by PKC down-regulation. The delayed onset of JNK activation by the mGlu1a receptor was not found to be a result of earlier ERK activation. Stimulations of mGlu1a/mGlu5a receptors, did not alter cellular proliferation, as measured by DNA synthesis, or have a marked effect on cytoskeletal organisation, as measured by immunocytochemistry, indicating that the activation of mitogenic signalling by these two mGlu receptors does not result in changes in growth in these cells. These studies highlight important differences in the activation and signalling pathways utilised to regulate MAP kinases

Metronidazole versus lactic acid for treating bacterial vaginosis (VITA): protocol for a randomised controlled trial to assess the clinical and cost effectiveness of topical lactic acid gel for treating second and subsequent episodes of bacterial vaginosis.

BACKGROUND Bacterial vaginosis (BV) affects 30-50% of women at some time in their lives and is an embarrassing and distressing condition which can be associated with potentially serious comorbidities. Current antibiotic treatments such as metronidazole are effective but can result in side effects, and recurrence is common. This trial aims to investigate whether lactic acid gel is clinically effective and cost effective in the treatment of recurrent BV compared with metronidazole. METHODS VITA is an open-label, multicentre, parallel group randomised controlled trial for women with a clinical diagnosis of BV and at least one previous BV episode in the past 2 years. Participants will be randomised 1:1 to intravaginal lactic acid gel 5 ml once daily for 7 days or oral metronidazole tablets 400 mg twice daily for 7 days. All participants will be followed up for 6 months to assess health status and healthcare costs. A subgroup will be interviewed to further explore adherence, tolerability and acceptability of treatment. The estimated sample size is 1900 participants to detect a 6% absolute increase in response rate to 86% in those receiving lactic acid gel. The primary outcome is participant-reported resolution of BV at Week 2. DISCUSSION Results from this trial will help inform UK treatment guidelines for BV and may provide an alternative effective treatment for recurrent episodes of this condition which avoids repeated exposure to antibiotics. TRIAL REGISTRATION ISRCTN, ISRCTN14161293. Registered on 8 September 2017

Gentamicin, azithromycin and ceftriaxone in the treatment of gonorrhoea: the relationship between antibiotic MIC and clinical outcome.

OBJECTIVES To investigate the relationship between MIC and clinical outcome in a randomized controlled trial that compared gentamicin 240 mg plus azithromycin 1 g with ceftriaxone 500 mg plus azithromycin 1 g. MIC analysis was performed on Neisseria gonorrhoeae isolates from all participants who were culture positive before they received treatment. METHODS Viable gonococcal cultures were available from 279 participants, of whom 145 received ceftriaxone/azithromycin and 134 received gentamicin/azithromycin. Four participants (6 isolates) and 14 participants (17 isolates) did not clear infection in the ceftriaxone/azithromycin and gentamicin/azithromycin arms, respectively. MICs were determined by Etest on GC agar base with 1% Vitox. The geometric mean MICs of azithromycin, ceftriaxone and gentamicin were compared using logistic and linear regression according to treatment received and N. gonorrhoeae clearance. RESULTS As the azithromycin MIC increased, gentamicin/azithromycin treatment was less effective than ceftriaxone/azithromycin at clearing N. gonorrhoeae. There was a higher geometric mean MIC of azithromycin for isolates from participants who had received gentamicin/azithromycin and did not clear infection compared with those who did clear infection [ratio 1.95 (95% CI 1.28-2.97)], but the use of categorical MIC breakpoints did not accurately predict the treatment response. The geometric mean MIC of azithromycin was higher in isolates from the pharynx compared with genital isolates. CONCLUSIONS We found that categorical resistance to azithromycin or ceftriaxone in vitro, and higher gentamicin MICs in the absence of breakpoints, were poorly predictive of treatment failure

Gentamicin as an alternative to ceftriaxone in the treatment of gonorrhoea: the G-TOG non-inferiority RCT.

BACKGROUND Gonorrhoea is a common sexually transmitted infection that can cause pain and discomfort, affect fertility in women and lead to epididymo-orchitis in men. Current treatment is with ceftriaxone, but there is increasing evidence of antimicrobial resistance reducing its effectiveness. Gentamicin is a potential alternative treatment requiring further evaluation. OBJECTIVES To assess the clinical effectiveness and cost-effectiveness of gentamicin as an alternative treatment to ceftriaxone in the treatment of gonorrhoea. DESIGN A multicentre, parallel-group, blinded, non-inferiority randomised controlled trial. SETTING Fourteen sexual health clinics in England. PARTICIPANTS Adults aged 16-70 years with a diagnosis of uncomplicated, untreated genital, pharyngeal or rectal gonorrhoea based on a positive Gram-stained smear on microscopy or a positive nucleic acid amplification test (NAAT). RANDOMISATION AND BLINDING Participants were randomised using a secure web-based system, stratified by clinic. Participants, investigators and research staff assessing participants were blinded to treatment allocation. INTERVENTIONS Allocation was to either 240 mg of gentamicin (intervention) or 500 mg of ceftriaxone (standard treatment), both administered as a single intramuscular injection. All participants also received 1 g of oral azithromycin. MAIN OUTCOME MEASURE The primary outcome measure was clearance of at all infected sites, confirmed by a negative Aptima Combo 2® (Hologic Inc., Marlborough, MA, USA) NAAT, at 2 weeks post treatment. RESULTS We randomised 720 participants, of whom 81% were men. There were 358 participants in the gentamicin group and 362 in the ceftriaxone group; 292 (82%) and 306 (85%) participants, respectively, were included in the primary analysis. Non-inferiority of gentamicin to ceftriaxone could not be demonstrated [adjusted risk difference for microbiological clearance -6.4%, 95% confidence interval (CI) -10.4% to -2.4%]. Clearance of genital infection was similar in the two groups, at 94% in the gentamicin group and 98% in the ceftriaxone group, but clearance of pharyngeal infection and rectal infection was lower in the gentamicin group (80% vs. 96% and 90% vs. 98%, respectively). Reported pain at the injection site was higher for gentamicin than for ceftriaxone. The side-effect profiles were comparable between the groups. Only one serious adverse event was reported and this was deemed not to be related to the trial medication. The economic analysis found that treatment with gentamicin is not cost neutral compared with standard care, with average patient treatment costs higher for those allocated to gentamicin (£13.90, 95% CI £2.47 to £37.34) than to ceftriaxone (£6.72, 95% CI £1.36 to £17.84). LIMITATIONS Loss to follow-up was 17% but was similar in both treatment arms. Twelve per cent of participants had a negative NAAT for gonorrhoea at their baseline visit but this was balanced between treatment groups and unlikely to have biased the trial results. CONCLUSIONS The trial was unable to demonstrate non-inferiority of gentamicin compared with ceftriaxone in the clearance of gonorrhoea at all infected sites. Clearance at pharyngeal and rectal sites was lower for participants allocated to gentamicin than for those allocated to ceftriaxone, but was similar for genital sites in both groups. Gentamicin was associated with more severe injection site pain. However, both gentamicin and ceftriaxone appeared to be well tolerated. FUTURE WORK Exploration of the genetic determinants of antibiotic resistance in will help to identify accurate markers of decreased susceptibility. Greater understanding of the immune response to infection can assist gonococcal vaccine development. TRIAL REGISTRATION Current Controlled Trials ISRCTN51783227. FUNDING This project was funded by the National Institute for Health Research Health Technology Assessment programme and will be published in full in ; Vol. 23, No. 20. See the NIHR Journals Library website for further project information

Acceptability of and treatment preferences for recurrent bacterial vaginosis-Topical lactic acid gel or oral metronidazole antibiotic: Qualitative findings from the VITA trial.

BACKGROUND Bacterial vaginosis (BV) is associated with an elevated vaginal pH and the presence of abnormal offensive discharge. It is common, often recurrent, and the most effective treatment regimen is unknown. 'Metronidazole Versus lactic acId for Treating bacterial vAginosis' (VITA) is a UK-based randomised controlled trial assessing clinical and cost-effectiveness of topical lactic acid gel compared to oral metronidazole antibiotic for treating second and subsequent BV episodes. Few BV trials report on women's preferences for treatment in the context of their own experiences. METHOD This qualitative study investigated the acceptability and tolerability of the two treatments. During the trial, semi-structured telephone interviews were undertaken between January-May 2018. A total of 33 women diagnosed with BV were consecutively sampled then interviewed from six sites across England. Thematic analysis was guided by the acceptability of health interventions framework. Potential causes of BV and its impact on women's lives were explored in addition to women's treatment preference and perceived treatment effectiveness. RESULTS Although women felt antibiotics treat BV effectively, and were associated with longer time periods between episodes, they generally preferred using the lactic acid gel because of ease of use, once daily application and less side-effects. Women would recommend the lactic acid gel to others for mild cases of BV but to take antibiotics when more severe. The risk of antibiotic drug resistance was a common concern. Self-help medicating or self-decision to not treat was also evident due to prior experience of poor outcomes from treatment. Triggers of BV were attributed to personal hygiene habits-soaps used to wash the vagina and sexual practices such as unprotected sex. CONCLUSION Acceptability and preference for topical lactic acid gel or oral metronidazole tablets in the treatment of recurrent BV was affected by personal choice relating to affective attitude, burden, ethicality, intervention coherence, opportunity costs, and self-efficacy. These differed depending on ease of use, tolerability and past experiences, but not necessarily based on perceived drug effectiveness. Knowledge of a patient preference for topical lactic acid gel therapy despite lower perceived effectiveness may be useful for clinicians when making treatment decisions