Fusidic acid cream in the treatment of impetigo in general practice: double blind randomised placebo controlled trial

Skin Diseases and their Treatment Strategies in Sub-Saharan African Regions

BACKGROUND

In the rural areas of sub-Saharan African regions, skin diseases are so common. Due to which the population of the sub-Saharan region suffers from different types of skin disorders. In these regions, many treatment options are not available for the treatment of skin disease.

AIM

The current study aims to discuss various skin diseases and their treatment strategies specifically in sub-Saharan African regions.

METHOD

Extensive literature survey was carried out by using scopus, science direct, elsevier, google scholar and bentham science databases.

RESULT AND DISCUSSION

It was demonstrated from the literature surveys that different effective techniques are used in the management of skin disease. In the result, it was shown that the condition of the disease is at a dangerous level which must be controlled.

CONCLUSION

It is concluded from the manuscript that the skin disorder in the sub-Saharan region is at a very dangerous level. The research must be done to develop a better understanding of the disease and its treatment.

A comparative review of current topical antibiotics for impetigo

INTRODUCTION

Impetigo is a superficial bacterial skin infection largely affecting the pediatric population. The objective of this review is to provide a comparison of mechanism of action, efficacy and safety of the available topical antibiotics for impetigo.

AREAS COVERED

Randomized clinical trials that evaluated the use of topical antibiotics for treatment of impetigo were included. Two thousand eighty-nine studies were initially identified, and five randomized clinical trials met the criteria for further analysis.

EXPERT OPINION

Topical antibiotics had greater resolution of impetigo in comparison to vehicle in these pivotal clinical trials. Adverse events were minimal, with the most common being pruritus at the application site. Cost or insurance coverage may be a limiting factor in choosing the best therapeutic agent, with mupirocin ointment having the lowest cost. Mupirocin has shown clinical efficacy against MRSA but a bacterial culture is recommended to rule out resistance. Ozenoxacin and retapamulin are effective alternatives but may entail higher cost. Retapamulin is indicated for lesions of impetigo that are colonized by MSSA and streptococcus S. pyogenes but not MRSA based on clinical efficacy of phase III trials. Fusidic acid, available in other countries, is a non-FDA approved medication although rising resistance rates represent a growing concern.

Interventions for bacterial folliculitis and boils (furuncles and carbuncles)

BACKGROUND

Bacterial folliculitis and boils are globally prevalent bacterial infections involving inflammation of the hair follicle and the perifollicular tissue. Some folliculitis may resolve spontaneously, but others may progress to boils without treatment. Boils, also known as furuncles, involve adjacent tissue and may progress to cellulitis or lymphadenitis. A systematic review of the best evidence on the available treatments was needed.

OBJECTIVES

To assess the effects of interventions (such as topical antibiotics, topical antiseptic agents, systemic antibiotics, phototherapy, and incision and drainage) for people with bacterial folliculitis and boils.

SEARCH METHODS

We searched the following databases up to June 2020: the Cochrane Skin Specialised Register, CENTRAL, MEDLINE, and Embase. We also searched five trials registers up to June 2020. We checked the reference lists of included studies and relevant reviews for further relevant trials.  SELECTION CRITERIA: We included randomised controlled trials (RCTs) that assessed systemic antibiotics; topical antibiotics; topical antiseptics, such as topical benzoyl peroxide; phototherapy; and surgical interventions in participants with bacterial folliculitis or boils. Eligible comparators were active intervention, placebo, or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane. Our primary outcomes were 'clinical cure' and 'severe adverse events leading to withdrawal of treatment'; secondary outcomes were 'quality of life', 'recurrence of folliculitis or boil following completion of treatment', and 'minor adverse events not leading to withdrawal of treatment'. We used GRADE to assess the certainty of the evidence.

MAIN RESULTS

We included 18 RCTs (1300 participants). The studies included more males (332) than females (221), although not all studies reported these data. Seventeen trials were conducted in hospitals, and one was conducted in clinics. The participants included both children and adults (0 to 99 years). The studies did not describe severity in detail; of the 232 participants with folliculitis, 36% were chronic. At least 61% of participants had furuncles or boils, of which at least 47% were incised. Duration of oral and topical treatments ranged from 3 days to 6 weeks, with duration of follow-up ranging from 3 days to 6 months. The study sites included Asia, Europe, and America. Only three trials reported funding, with two funded by industry. Ten studies were at high risk of 'performance bias', five at high risk of 'reporting bias', and three at high risk of 'detection bias'. We did not identify any RCTs comparing topical antibiotics against topical antiseptics, topical antibiotics against systemic antibiotics, or phototherapy against sham light. Eleven trials compared different oral antibiotics. We are uncertain as to whether cefadroxil compared to flucloxacillin (17/21 versus 18/20, risk ratio (RR) 0.90, 95% confidence interval (CI) 0.70 to 1.16; 41 participants; 1 study; 10 days of treatment) or azithromycin compared to cefaclor (8/15 versus 10/16, RR 1.01, 95% CI 0.72 to 1.40; 31 participants; 2 studies; 7 days of treatment) differed in clinical cure (both very low-certainty evidence). There may be little to no difference in clinical cure rate between cefdinir and cefalexin after 17 to 24 days (25/32 versus 32/42, RR 1.00, 95% CI 0.73 to 1.38; 74 participants; 1 study; low-certainty evidence), and there probably is little to no difference in clinical cure rate between cefditoren pivoxil and cefaclor after 7 days (24/46 versus 21/47, RR 1.17, 95% CI 0.77 to 1.78; 93 participants; 1 study; moderate-certainty evidence). For risk of severe adverse events leading to treatment withdrawal, there may be little to no difference between cefdinir versus cefalexin after 17 to 24 days (1/191 versus 1/200, RR 1.05, 95% CI 0.07 to 16.62; 391 participants; 1 study; low-certainty evidence). There may be an increased risk with cefadroxil compared with flucloxacillin after 10 days (6/327 versus 2/324, RR 2.97, 95% CI 0.60 to 14.62; 651 participants; 1 study; low-certainty evidence) and cefditoren pivoxil compared with cefaclor after 7 days (2/77 versus 0/73, RR 4.74, 95% CI 0.23 to 97.17; 150 participants; 1 study; low-certainty evidence). However, for these three comparisons the 95% CI is very wide and includes the possibility of both increased and reduced risk of events. We are uncertain whether azithromycin affects the risk of severe adverse events leading to withdrawal of treatment compared to cefaclor (274 participants; 2 studies; very low-certainty evidence) as no events occurred in either group after seven days. For risk of minor adverse events, there is probably little to no difference between the following comparisons: cefadroxil versus flucloxacillin after 10 days (91/327 versus 116/324, RR 0.78, 95% CI 0.62 to 0.98; 651 participants; 1 study; moderate-certainty evidence) or cefditoren pivoxil versus cefaclor after 7 days (8/77 versus 5/73, RR 1.52, 95% CI 0.52 to 4.42; 150 participants; 1 study; moderate-certainty evidence). We are uncertain of the effect of azithromycin versus cefaclor after seven days due to very low-certainty evidence (7/148 versus 4/126, RR 1.26, 95% CI 0.38 to 4.17; 274 participants; 2 studies). The study comparing cefdinir versus cefalexin did not report data for total minor adverse events, but both groups experienced diarrhoea, nausea, and vaginal mycosis during 17 to 24 days of treatment. Additional adverse events reported in the other included studies were vomiting, rashes, and gastrointestinal symptoms such as stomach ache, with some events leading to study withdrawal. Three included studies assessed recurrence following completion of treatment, none of which evaluated our key comparisons, and no studies assessed quality of life.

AUTHORS' CONCLUSIONS

We found no RCTs regarding the efficacy and safety of topical antibiotics versus antiseptics, topical versus systemic antibiotics, or phototherapy versus sham light for treating bacterial folliculitis or boils. Comparative trials have not identified important differences in efficacy or safety outcomes between different oral antibiotics for treating bacterial folliculitis or boils. Most of the included studies assessed participants with skin and soft tissue infection which included many disease types, whilst others focused specifically on folliculitis or boils. Antibiotic sensitivity data for causative organisms were often not reported. Future trials should incorporate culture and sensitivity information and consider comparing topical antibiotic with antiseptic, and topical versus systemic antibiotics or phototherapy.

Natural history of non-bullous impetigo: a systematic review of time to resolution or improvement without antibiotic treatment

Background

Non-bullous impetigo is typically treated with antibiotics. However, the duration of symptoms without their use has not been established, which hampers informed decision making about antibiotic use.

Aim

To determine the natural history of non-bullous impetigo.

Design and setting

Systematic review.

Method

The authors searched PubMed up to January 2020, as well as reference lists of articles identified in the search. Eligible studies involved participants with impetigo in either the placebo group of randomised trials, or in single-group prognostic studies that did not use antibiotics and measured time to resolution or improvement. A modified version of a risk of bias assessment for prognostic studies was used. Outcomes were percentage of participants who had either symptom resolution, symptom improvement, or failed to improve at any timepoint. Adverse event data were also extracted.

Results

Seven randomised trials (557 placebo group participants) were identified. At about 7 days, the percentage of participants classified as resolved ranged from 13% to 74% across the studies, whereas the percentage classified as ‘failure to improve’ ranged from 16% to 41%. The rate of adverse effects was low. Incomplete reporting of some details limited assessment of risk of bias.

Conclusion

Although some uncertainty around the natural history of non-bullous impetigo remains, symptoms resolve in some patients by about 7 days without using antibiotics, with about one-quarter of patients not improving. Immediate antibiotic use may not be mandatory, and discussions with patients should include the expected course of untreated impetigo and careful consideration of the benefits and harms of antibiotic use.

Human organoid biofilm model for assessing antibiofilm activity of novel agents

Bacterial biofilms cause 65% of all human infections and are highly resistant to antibiotic therapy but lack specific treatments. To provide a human organoid model for studying host-microbe interplay and enabling screening for novel antibiofilm agents, a human epidermis organoid model with robust methicillin-resistant Staphylococcus aureus (MRSA) USA300 and Pseudomonas aeruginosa PAO1 biofilm was developed. Treatment of 1-day and 3-day MRSA and PAO1 biofilms with antibiofilm peptide DJK-5 significantly and substantially reduced the bacterial burden. This model enabled the screening of synthetic host defense peptides, revealing their superior antibiofilm activity against MRSA compared to the antibiotic mupirocin. The model was extended to evaluate thermally wounded skin infected with MRSA biofilms resulting in increased bacterial load, cytotoxicity, and pro-inflammatory cytokine levels that were all reduced upon treatment with DJK-5. Combination treatment of DJK-5 with an anti-inflammatory peptide, 1002, further reduced cytotoxicity and skin inflammation.

Clustering by Health Professionals in Individually Randomised Controlled Trials

Purpose: The aim of this study was to investigate the prevalence of clustering by health professionals in individually randomised controlled trials (iRCT), and its adjustment in both the sample size calculation estimates and the analysis of the data collected in iRCT (that is, trials that randomise individuals only). As a result, cluster randomised controlled trials will not be the part of this review study. Additionally, the authors aimed to discover the prevalence of the various forms of clustering in iRCT. Methods: iRCT, in which the intervention was delivered by a health professional, were electronically searched in three medical journals. The dates searched were from 1st January 2000–31st August 2009. The retrieved trials were then screened to exclude those with complex designs and trials with more than two parallel arms. The selected trials were then fully reviewed for the presence of clustering effects and any corresponding adjustment. Data about the sample size calculation in the selected trials were also included. A basic form was generated for the purpose of data extraction from each of the selected trials. Results: Of the 130 iRCT reviewed, clustering of outcomes was present in 127 (98%) trials. Only 61 trials (47%) had adjusted for the clustering effects in their design and analysis, while 53% of the trials had ignored the clustering effect, and hence no adjustment had been made in the trial design or analysis. Regarding the various forms of clustering, clustering by centre in multicentre trials was found in 79 trials (60%), followed by natural clustering in 26 trials (20%), and clustering imposed by the design of the study in 23 trials (18%). Conclusion: Potential clustering of outcomes exists in almost all iRCT; however, this review found that <50% of iRCT took clustering into account and adjusted the sample size calculation and statistical analysis of this data for clustering. Almost half of the reviewed iRCT ignored the clustering effect. As a result, inaccurate and nongeneralisable results could have been generated.

Efficacy and Safety of Ozenoxacin Cream for Treatment of Adult and Pediatric Patients With Impetigo: A Randomized Clinical Trial

Importance

Ozenoxacin, a novel topical antibacterial agent with potent bactericidal activity against gram-positive bacteria, has been developed as a cream with 1% active drug for the treatment of impetigo, a highly contagious bacterial skin infection.

Objectives

To evaluate the efficacy, safety, and tolerability of ozenoxacin cream, 1%, after 5-day twice-daily topical treatment in patients with impetigo.

Design, Setting, and Participants

This randomized, double-blind, vehicle-controlled clinical trial included patients 2 months or older with impetigo who were enrolled at centers in 6 countries from June 2, 2014, through May 30, 2015. Data were analyzed based on intention to treat from July 9 through July 22, 2015.

Interventions

Patients were randomized 1:1 to receive topical ozenoxacin or placebo control.

Main Outcomes and Measures

Efficacy was measured using the Skin Infection Rating Scale and microbiological culture. Safety and tolerability were also evaluated.

Results

Among the 411 patients who received treatment (210 males [51.1%]; mean [SD] age, 18.6 [18.3] years), ozenoxacin demonstrated superior clinical success compared with placebo, which was evident after 5 days of therapy (112 of 206 [54.4%] vs 78 of 206 [37.9%]; P = .001). Ozenoxacin also demonstrated superior microbiological success compared with placebo after 2 days of therapy (109 of 125 [87.2%] vs 76 of 119 [63.9%]; P = .002). Ozenoxacin was well tolerated, with 8 of 206 patients experiencing adverse effects, with only 1 of these potentially related to the study treatment; none were serious.

Conclusions and Relevance

Topical ozenoxacin is effective and well tolerated in the treatment of impetigo in patients 2 months and older. This effect is demonstrated by rapid onset of response and superior clinical and microbiological response compared with placebo. Topical ozenoxacin represents a novel option for the treatment of impetigo.

Trial Registration

ClinicalTrials.gov Identifier: NCT02090764.

Current and Emerging Topical Antibacterials and Antiseptics: Agents, Action, and Resistance Patterns

Bacterial skin infections represent some of the most common infectious diseases globally. Prevention and treatment of skin infections can involve application of a topical antimicrobial, which may be an antibiotic (such as mupirocin or fusidic acid) or an antiseptic (such as chlorhexidine or alcohol). However, there is limited evidence to support the widespread prophylactic or therapeutic use of topical agents. Challenges involved in the use of topical antimicrobials include increasing rates of bacterial resistance, local hypersensitivity reactions (particularly to older agents, such as bacitracin), and concerns about the indiscriminate use of antiseptics potentially coselecting for antibiotic resistance. We review the evidence for the major clinical uses of topical antibiotics and antiseptics. In addition, we review the mechanisms of action of common topical agents and define the clinical and molecular epidemiology of antimicrobial resistance in these agents. Moreover, we review the potential use of newer and emerging agents, such as retapamulin and ebselen, and discuss the role of antiseptic agents in preventing bacterial skin infections. A comprehensive understanding of the clinical efficacy and drivers of resistance to topical agents will inform the optimal use of these agents to preserve their activity in the future.

[Treatment of superficial bacterial cutaneous infections: a survey among general practitioners in France]

BACKGROUND

Superficial bacterial skin infection and superinfection of skin diseases are usually treated by general practitioners using antiseptics or antibiotics. However, acquired resistance to biocidal agents, both systemic and topical, is growing.

OBJECTIVES OF THE STUDY

Our aim was to assess the skill of GPs in clinical situations involving common skin infections.

MATERIAL AND METHODS

On 16 June 2010, we sent a questionnaire to all GPs in a rural region of France (the Cher department) together with a stamped addressed envelope for the reply. The questionnaire contained seven pages of multiple-choice questions and five clinical cases, each one illustrated with a photograph (sty, furuncle, whitlow, colonized chronic wounds and impetigo). Anonymity of responses was guaranteed. Data was analysed using the Clinsight(®) software package.

RESULTS

The response rate was 51% (102 responses). GPs reported little difficulty in treating these patients (median 3, range 1 to 8 on a scale of increasing difficulty from 0 to 10). The main results of the study are firstly the frequency of combination of at least one antiseptic with one antibiotic (46%); secondly, the frequency of combination of two antibiotics (20% of cases); thirdly, the frequent prescription of systemic antibiotics for chronic wounds colonized by Pseudomonas aeruginosa (61%).

DISCUSSION

Our study shows the high frequency of prescriptions for combined therapy to treat superficial skin infections despite the fact that monotherapy with either an antiseptic or an antibiotic would probably suffice. It also shows the unnecessary prescription of antibiotics for colonization of a chronic wound. The study was limited in terms of size and design: it was a questionnaire rather than an analysis of prescriptions actually made in "real life", and the response rate was 51%. In addition, aside from impetigo, for which randomised studies and recommendations were given, the other surface infections (sty, folliculitis, whitlow) tend to be treated more empirically.

CONCLUSION

Dissemination of recommendations regarding the respective role of antiseptics and antibiotics (and their route of administration, topical or systemic) in superficial skin infections would doubtless be useful for prescribers, and more rational use of these agents would help limit bacterial resistance.

Interventions for impetigo

BACKGROUND

Impetigo is a common, superficial bacterial skin infection, which is most frequently encountered in children. There is no generally agreed standard therapy, and guidelines for treatment differ widely. Treatment options include many different oral and topical antibiotics as well as disinfectants. This is an updated version of the original review published in 2003.

OBJECTIVES

To assess the effects of treatments for impetigo, including non-pharmacological interventions and 'waiting for natural resolution'.

SEARCH METHODS

We updated our searches of the following databases to July 2010: the Cochrane Skin Group Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (from 2005), EMBASE (from 2007), and LILACS (from 1982). We also searched online trials registries for ongoing trials, and we handsearched the reference lists of new studies found in the updated search.

SELECTION CRITERIA

Randomised controlled trials of treatments for non-bullous, bullous, primary, and secondary impetigo.

DATA COLLECTION AND ANALYSIS

Two independent authors undertook all steps in data collection. We performed quality assessments and data collection in two separate stages.

MAIN RESULTS

We included 57 trials in the first version of this review. For this update 1 of those trials was excluded and 12 new trials were added. The total number of included trials was, thus, 68, with 5578 participants, reporting on 50 different treatments, including placebo. Most trials were in primary impetigo or did not specify this.For many of the items that were assessed for risk of bias, most studies did not provide enough information. Fifteen studies reported blinding of participants and outcome assessors.Topical antibiotic treatment showed better cure rates than placebo (pooled risk ratio (RR) 2. 24, 95% confidence interval (CI) 1.61 to 3.13) in 6 studies with 575 participants. In 4 studies with 440 participants, there was no clear evidence that either of the most commonly studied topical antibiotics (mupirocin and fusidic acid) was more effective than the other (RR 1.03, 95% CI 0.95 to 1.11).In 10 studies with 581 participants, topical mupirocin was shown to be slightly superior to oral erythromycin (pooled RR 1.07, 95% CI 1.01 to 1.13). There were no significant differences in cure rates from treatment with topical versus other oral antibiotics. There were, however, differences in the outcome from treatment with different oral antibiotics: penicillin was inferior to erythromycin, in 2 studies with 79 participants (pooled RR 1.29, 95% CI 1.07 to 1.56), and cloxacillin, in 2 studies with 166 participants (pooled RR 1.59, 95% CI 1.21 to 2.08).There was a lack of evidence for the benefit of using disinfectant solutions. When 2 studies with 292 participants were pooled, topical antibiotics were significantly better than disinfecting treatments (RR 1.15, 95% CI 1.01 to 1.32).The reported number of side-effects was low, and most of these were mild. Side-effects were more common for oral antibiotic treatment compared to topical treatment. Gastrointestinal effects accounted for most of the difference.Worldwide, bacteria causing impetigo show growing resistance rates for commonly used antibiotics. For a newly developed topical treatment, retapamulin, no resistance has yet been reported.

AUTHORS' CONCLUSIONS

There is good evidence that topical mupirocin and topical fusidic acid are equally, or more, effective than oral treatment. Due to the lack of studies in people with extensive impetigo, it is unclear if oral antibiotics are superior to topical antibiotics in this group. Fusidic acid and mupirocin are of similar efficacy. Penicillin was not as effective as most other antibiotics. There is a lack of evidence to support disinfection measures to manage impetigo.

Modelling of the outcome of non-inferiority trials by integration of historical data

The approval and differentiation of new compounds in clinical development often demands non-inferiority trials, in which the test drug is compared against a reference treatment. However, non-inferiority trials impose major operational burden with serious ethical and scientific implications for the development of new medicines. Traditional approaches make limited use of historical information on placebo and neglect inter-trial variability, relying on the constancy assumption that the control-to-placebo effect size is maintained across trials. We propose a model-based approach that overcomes such limitations and may be used as a tool to explore differentiation during clinical development. Parameter distributions are introduced which reflect the heterogeneity of trials. The method is illustrated using data from impetigo trials. Based on simulation scenarios, this Bayesian technique yields a definitive, consistent increase in the statistical power over two accepted statistical methods, allowing lower sample size requirements for the assessment of non-inferiority.

Staphylococcus aureus carriage among GPs in The Netherlands

BACKGROUND

The extent to which GPs serve as a reservoir for antibiotic-resistant Staphylococcus aureus is unknown and not well studied.

AIM

To determine the prevalence of nasal S. aureus carriage among GPs in the Netherlands, as well as the antimicrobial resistance and the genotypes of isolated S. aureus.

DESIGN OF STUDY

Observational, point-prevalence, and cross-sectional study.

SETTING

GPs attending the annual conference of the Dutch College of General Practitioners in 2006.

METHOD

Nasal swabs were randomly taken from 395 GPs and analysed for the presence of S. aureus. Antimicrobial susceptibility was determined by a microbroth dilution method and the genotypes by spa typing, which was associated with multilocus sequence typing.

RESULTS

Of the GPs, 129/395 (33%; 95% confidence interval [CI] = 28 to 37%) were carriers of S. aureus. No meticillin-resistant S. aureus (MRSA) was found. Resistance was observed to penicillin (71%; 95% CI = 63 to 79%), fusidic acid (7%; 95% CI = 3 to 13%), and clarithromycin (6%; 95% CI = 3 to 12%). In 72% of the isolates, an MRSA-related genotype of S. aureus was found.

CONCLUSION

The low antibiotic resistance found among S. aureus of GPs suggests that GPs are not a reservoir of antibiotic-resistant S. aureus strains. The relatively high resistance to fusidic acid, which has not previously been described in the Netherlands and is mostly because of antibiotic use, suggests that patients infect GPs and not the other way round. GPs may be at risk for nasal carriage of S. aureus with an MRSA-related genotype.

Evaluation of antibacterial activity of proteins and peptides using a specific animal model for wound healing

Wound healing is a complex process involving the integrated actions of numerous cell types, soluble mediators, and extracellular matrix (ECM). In this study, phospholipase A(2) (PLA(2)) purified from crotalid snake venom was found to express in vitro bactericidal activity against a group of clinical human pathogens. Based on the sequence homology of PLA(2), a series of peptides were derived from the C-terminal region of crotalid PLA(2). These short synthetic peptides were found to reproduce the bactericidal activity of its parent molecule. In vitro assays for bactericidal and cytolytic activities of these peptides showed very high microbicidal potency against Gram-negative and Gram-positive (Staphylococcus aureus) bacteria. Variants of the peptides showed reduced toxicity toward normal human cells, while retaining high bactericidal potency. Here we describe the protocol for evaluating the wound healing process by antibacterial peptides. We evaluated the biological roles of the candidate peptides in skin wound healing, using a specific BALB/c mice model. Peptide-treated animals showed accelerated healing of full-thickness skin wounds, with increased reepithelialization, collagen synthesis, and angiogenesis observed during the healing process. Healing wounds in protein/peptide-treated mice had higher densities of neutrophils, macrophages, and fibrocytes. Along with increased leukocyte infiltration, levels of macrophage-derived chemokine expression were also upregulated. These results demonstrate that the protein/peptide derived from snake venoms promotes healing of skin wounds. The primary mechanism seems to be an increase in leukocyte infiltration, leading to locally elevated synthesis and release of collagen and growth factors.

Scabies and pyodermas--diagnosis and treatment

Scabies and pyodermas are two of the commonest skin infections in tropical settings. They affect large numbers of people, particularly children, and account for a large burden of disease for peripheral health care teams. Despite this there have been significant advances in our knowledge of these diseases, their impact and their management. However there is a need to evaluate these developments in this specific setting, tropical health and in the context of communities with limited resources. This section will describe these advances and the challenges that remain.

Staphylococcus aureus in dermatology outpatients with special emphasis on community-associated methicillin-resistant strains

Methicillin-resistant Staphylococcus aureus (MRSA) emerged as a community-associated pathogen (CA-MRSA) in the past 6 years. This prospective study investigated dermatology outpatients with inflammatory skin diseases, leg ulcers, and skin infections for Panton-Valentine leukocidin (PVL)-positive S. aureus, often associated with deep skin infection. In case of PVL positivity, molecular typing and PCR demonstration of resistance genes were performed. Out of 248 patients, 130 carried S. aureus, 24 being lukS-PV lukF-PV positive. Eighteen were MRSA, 11 of them belonging to the multilocus sequence typing clonal complex (CC)5, 1 to CC45, and 2/18 to CC8. Out of 18 patients, 4 were CA-MRSA containing lukS-PV lukF-PV as an important trait of CA-MRSA. Out of four CA-MRSA isolates, two were of type ST080 containing far-1 coding for fusidic acid (FUS) resistance and two were FUS sensitive (ST152 and ST001). The FUS-sensitive CA-MRSA, which corresponded to the CA-MRSA of ST001 from the United States, was detected in Germany for the first time, indicating that dermatologists are first in line to detect CA-MRSA. In contrast to CA-MRSA from other continents, far-1-coded FUS resistance represents a typical marker for the widespread CA-MRSA ST080 in Europe, especially in Germany. The significant risk factor for the acquisition of CA-MRSA was visits to foreign countries and/or professional or private contacts with foreigners.

Topical Retapamulin Ointment, 1%, versus Sodium Fusidate Ointment, 2%, for Impetigo: A Randomized, Observer-Blinded, Noninferiority Study

BACKGROUND

Retapamulin is a novel pleuromutilin antibacterial developed for topical use.

OBJECTIVE

To compare the efficacy and safety of retapamulin ointment, 1% (twice daily for 5 days), with sodium fusidate ointment, 2% (3 times daily for 7 days), in impetigo.

METHODS

A randomized (2:1 retapamulin to sodium fusidate), observer-blinded, noninferiority, phase III study in 519 adult and pediatric (aged > or = 9 months) subjects.

RESULTS

Retapamulin and sodium fusidate had comparable clinical efficacies (per-protocol population: 99.1 and 94.0%, respectively; difference: 5.1%, 95% confidence interval: 1.1-9.0%, p = 0.003; intent-to-treat population: 94.8 and 90.1%, respectively; difference: 4.7%, 95% confidence interval: -0.4 to 9.7%, p = 0.062). Bacteriological efficacies were similar. Success rates in the small numbers of sodium-fusidate-, methicillin- and mupirocin-resistant Staphylococcus aureus were good for retapamulin (9/9, 8/8 and 6/6, respectively). Both drugs were well tolerated.

CONCLUSION

Retapamulin is a highly effective and convenient new treatment option for impetigo, with efficacy against isolates resistant to existing therapies.

Current options for the treatment of impetigo in children

Impetigo contagiosa is a common, superficial, bacterial infection of the skin characterised by an inflamed and infected epidermis caused by Staphylococcus aureus, Streptococcus pyogenes or both. The less common bullous impetigo is characterised by fragile fluid-filled vesicles and flaccid blisters, and is invariably caused by pathogenic strains of S. aureus. In bullous impetigo, exfoliative toxins are produced, although these are restricted to the area of infection and bacteria can be cultured from the blister contents. In the rare variant, staphylococcal scalded skin syndrome, the exfoliative toxins are spread haematogenously from a localised source causing widespread epidermal damage at distant sites.

Impetigo in epidemic and nonepidemic phases: an incidence study over 4½ years in a general population

BACKGROUND

Little is known about incidence and natural variation of impetigo in general populations.

OBJECTIVES

To investigate the natural course of impetigo in a well-defined population, and to study the resistance pattern of the causal bacteria over time.

METHODS

This is a population-based incidence study in Austevoll, an island community of 4457 inhabitants in Norway, in the years 2001-2005. Incidence rates are given as events per person-year. Epidemic periods were identified by statistical process-control analyses.

RESULTS

The incidence rate of impetigo for the whole study period was 0.017 events per person-year, corresponding to a total of 334 cases. The incidence rates were 0.009, 0.026, 0.019, 0.016 and 0.009 in the years 2001, 2002, 2003, 2004 and 2005, respectively. Three epidemics were identified, starting in August of 2002, 2003 and 2004, lasting for 11, 11 and 5 weeks, respectively. Incidence rates in these epidemic periods were 0.099, 0.045 and 0.074, respectively. In epidemic periods, Staphylococcus aureus was the causal bacterium in 89% (117/132) of cases, while this proportion was 68% (84/123) in nonepidemic periods (P < 0.01). Staphylococcus aureus was resistant to fusidic acid in 84% (98/117) and 64% (54/84) of impetigo cases in epidemic and nonepidemic periods, respectively (P < 0.01). When investigating all types of infections caused by S. aureus in the study period, the proportion of fusidic acid resistance in impetigo cases (152/201, 76%) differed significantly from fusidic acid resistance in other infections (18/116, 16%) (P < 0.01).

CONCLUSIONS

Distinctive epidemic outbreaks occurred during the summer of three of the five follow-up years. In outbreaks, S. aureus was more frequently the causal agent and the sensitivity to fusidic acid decreased significantly.

The use of random effects models to allow for clustering in individually randomized trials

BACKGROUND

We describe different forms of clustering that may occur in individually randomized trials, where the observed outcomes for different individuals cannot be regarded as independent. We propose random effects models to allow for such clustering, across a range of contexts and trial designs, and investigate their effect on estimation and interpretation of the treatment effect.

METHODS

We apply our proposed models to two individually randomized trials with potential for clustering, a trial of teleconsultation in hospital referral (the main outcome being offer of a further hospital appointment) and a trial of exercise therapy delivered by physiotherapists for low back pain (the outcome being a back pain score). Extensions to the methods include the possibility of explaining heterogeneity between clusters using cluster level characteristics and the potential dilution of cluster effects due to noncompliance.

RESULTS

In the teleconsultation trial, the odds ratio was significant (1.52, 95% CI 1.27 to 1.82) when clustering was ignored, but smaller and nonsignificant (1.36, 95% CI 0.85 to 2.13) when clustering by hospital consultant was taken into account. The 95% range of estimated treatment effects across consultants was from 0.21 to 8.76. This variability was only partially explained by the specialty of the consultant. In the back pain trial, although there was an overall benefit of exercise (change of - 0.51 points on the back pain score) and little evidence of clustering, the estimated treatment effects for different physiotherapists ranged from -1.26 to +0.26 points.

CONCLUSIONS

Clustering is an important issue in many individually randomized trials. Ignoring it can lead to underestimates of the uncertainty and too extreme P-values. Even when there is little apparent heterogeneity across clusters, it can still have a large impact on the estimation and interpretation of the treatment effect.

What is the evidence for tissue regeneration impairment when using a formulation of PVP-I antiseptic on open wounds?

Wound care and the use of antiseptics has long been the subject of much debate within the health professional's literature. This study was undertaken to determine the range of literature available on povidone-iodine (PVP-I) antiseptic use and the evidence supporting the outcomes reported. A range of articles was collected and divided into subgroups based on hierarchy of evidence and the five evidence dimensions [1]. Using the READER scoring tool, articles were evaluated and given a numerical award between 4 and 25 as a determinant of their quality in method, statistical analysis and outcome measures, with those scoring 12.5 or higher (from a possible 25) deemed as offering a satisfactory level of evidence. Statistical analysis on the results prior to applying the READER scoring tool found that overall 49% of articles did not support PVP-I use. However, this situation changed when the quality of evidence was limited to articles scoring >12.5. The higher-scored articles showed a 71% support for the continued use of PVP-I. The outcome of this study shows that there is reason for further debate over the use of PVP-I.

Staphylococcal skin infections in children: rational drug therapy recommendations

Staphylococcus aureus remains one of the most common and troublesome of bacteria causing disease in humans, despite the development of effective antibacterials and improvement in hygiene. The organism is responsible for over 70% of all skin and soft tissue infections in children and accounts for up to one-fifth of all visits to pediatric clinics. Skin and soft tissue infections that are predominantly caused by S. aureus include bullous and non-bullous impetigo, folliculitis, furunculosis, carbunculosis, cellulitis, surgical and traumatic wound infections, mastitis, and neonatal omphalitis. Other skin and soft tissue infections may also be caused by S. aureus but are often polymicrobial in origin and require special consideration. These include burns, decubitus ulcers (particularly in the perianal region), puncture wounds of the foot, as well as human and mammalian bites. Treatment of staphylococcal skin infections varies from topical antiseptics to prolonged intravenous antibacterials, depending on severity of the lesions and the health of the child. The treatment of choice for oral antibacterials remains the penicillinase-resistant penicillins such as flucloxacillin. Cefalexin and erythromycin are suitable cost-effective alternatives with broader cover, although care must be taken with the use of macrolides because of development of resistance to multiple families of antibacterials, particularly the lincosamides. Other cephalosporins such as cefadroxil and cefprozil are also effective, can be given once daily and have a better tolerability profile -- while azithromycin has a further advantage of a 3-day course. However, all of these agents are more expensive. Although the antibacterials have been given for 10 days in most clinical trials, there is no evidence that this duration is more effective than a 7-day course. In children requiring intravenous therapy, ceftriaxone has a major advantage over other antibacterials such as sulbactam/ampicillin and cefuroxime in that it can be given once daily and may, therefore, be suitable for outpatient treatment of moderate-to-severe skin infections. Newer-generation cephalosporins and loracarbef are also effective and have a broader spectrum of activity, but do not offer any added benefit and are significantly more expensive. Skin and soft tissue infections due to methicillin-resistant S. aureus (MRSA) are still relatively uncommon in children. Well children with community-acquired MRSA infections can be treated with clindamycin or trimethoprim-sulfamethoxazole (cotrimoxazole), but must be observed closely for potentially severe adverse effects. In severe infections, vancomycin remains the treatment of choice, while intravenous teicoplanin and clindamycin are suitable alternatives. Linezolid and quinupristin/dalfopristin are currently showing great promise for the treatment of multi-resistant Gram-positive infections. While the choice of antibacterial is important, supportive management, including removal of any infected foreign bodies, surgical drainage of walled-off lesions, and regular wound cleaning, play a vital role in ensuring cure.

Dumb and Dumber--The Potential Waste of a Useful Antistaphylococcal Agent: Emerging Fusidic Acid Resistance in Staphylococcus aureus

Fusidic acid has activity against a range of pathogens but has mainly been used to treat staphylococcal infections. Fusidic acid monotherapy, especially topical preparations, has been strongly associated with the emergence of fusidic acid resistance among both methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-susceptible S. aureus. Key resistance determinants include mutations in the fusA gene, which encodes elongation factor G, and plasmid-mediated resistance (i.e., acquisition of resistance gene fusB). Clonal outbreaks of fusidic acid-resistant S. aureus have been noted throughout the United Kingdom and Europe, such that the efficacy of fusidic acid is threatened. Fusidic acid in combination with other agents, such as rifampicin, has proven effective for difficult-to-treat MRSA infections and provides a convenient oral alternative to oxazolidinones. Ensuring that systemic fusidic acid is always used in combination and that the use of topical fusidic acid is either abolished or restricted will be vital if we are to prevent the loss of this potentially useful agent.

Clustering by health professional in individually randomised trials

Patient outcomes in many randomised trials depend crucially on the health professional delivering the intervention, but the resulting clustering is rarely considered in the analysis

Natural population dynamics and expansion of pathogenic clones of Staphylococcus aureus

The population structure of Staphylococcus aureus carried by healthy humans was determined using a large strain collection of nonclinical origin (n = 829). High-throughput amplified fragment length polymorphism (AFLP) analysis revealed 3 major and 2 minor genetic clusters of S. aureus, which were corroborated by multilocus sequence typing. Major AFLP cluster I comprised 44.4% of the carriage isolates and showed additional heterogeneity whereas major AFLP groups II and III presented 2 homogeneous clusters, including 47.3% of all carriage isolates. Coanalysis of invasive S. aureus strains and epidemic methicillin-resistant S. aureus (MRSA) revealed that all major clusters contained invasive and multiresistant isolates. However, clusters and subclusters with overrepresentation of invasive isolates were also identified. Bacteremia in elderly adults, for instance, was caused by a IVa cluster-derived strain significantly more often than by strains from other AFLP clusters. Furthermore, expansion of multiresistant clones or clones associated with skin disease (impetigo) was detected, which suggests that epidemic potential is present in pathogenic strains of S. aureus. In addition, the virulence gene encoding Panton-Valentine leukocidin was significantly enriched in S. aureus strains causing abscesses and arthritis in comparison with the carriage group. We provide evidence that essentially any S. aureus genotype carried by humans can transform into a life-threatening human pathogen but that certain clones are more virulent than others.

Improving health care globally: a critical review of the necessity of family medicine research and recommendations to build research capacity

An invitational conference led by the World Organization of Family Doctors (Wonca) involving selected delegates from 34 countries was held in Kingston, Ontario, Canada, March 8 to 12, 2003. The conference theme was "Improving Health Globally: The Necessity of Family Medicine Research." Guiding conference discussions was the value that to improve health care worldwide, strong, evidence-based primary care is indispensable. Eight papers reviewed before the meeting formed the basic material from which the conference developed 9 recommendations. Wonca, as an international body of family medicine, was regarded as particularly suited to pursue these conference recommendations: 1. Research achievements in family medicine should be displayed to policy makers, health (insurance) authorities, and academic leaders in a systematic way. 2. In all countries, sentinel practice systems should be developed to provide surveillance reports on illness and diseases that have the greatest impact on the population's health and wellness in the community. 3. A clearinghouse should be organized to provide a central repository of knowledge about family medicine research expertise, training, and mentoring.4. National research institutes and university departments of family medicine with a research mission should be developed. 5. Practice-based research networks should be developed around the world.6. Family medicine research journals, conferences, and Web sites should be strengthened to disseminate research findings internationally, and their use coordinated. Improved representation of family medicine research journals in databases, such as Index Medicus, should be pursued.7. Funding of international collaborative research in family medicine should be facilitated.8. International ethical guidelines, with an international ethical review process, should be developed in particular for participatory (action) research, where researchers work in partnership with communities. 9. When implementing these recommendations, the specific needs and implications for developing countries should be addressed.The Wonca executive committee has reviewed these recommendations and the supporting rationale for each. They plan to follow the recommendations, but to do so will require the support and cooperation of many individuals, organizations, and national governments around the world.

Improving health care globally: a critical review of the necessity of family medicine research and recommendations to build research capacity

An invitational conference led by the World Organization of Family Doctors (Wonca) involving selected delegates from 34 countries was held in Kingston, Ontario, Canada, March 8 to 12, 2003. The conference theme was "Improving Health Globally: The Necessity of Family Medicine Research." Guiding conference discussions was the value that to improve health care worldwide, strong, evidence-based primary care is indispensable. Eight papers reviewed before the meeting formed the basic material from which the conference developed 9 recommendations. Wonca, as an international body of family medicine, was regarded as particularly suited to pursue these conference recommendations: 1. Research achievements in family medicine should be displayed to policy makers, health (insurance) authorities, and academic leaders in a systematic way. 2. In all countries, sentinel practice systems should be developed to provide surveillance reports on illness and diseases that have the greatest impact on the population's health and wellness in the community. 3. A clearinghouse should be organized to provide a central repository of knowledge about family medicine research expertise, training, and mentoring.4. National research institutes and university departments of family medicine with a research mission should be developed. 5. Practice-based research networks should be developed around the world.6. Family medicine research journals, conferences, and Web sites should be strengthened to disseminate research findings internationally, and their use coordinated. Improved representation of family medicine research journals in databases, such as Index Medicus, should be pursued.7. Funding of international collaborative research in family medicine should be facilitated.8. International ethical guidelines, with an international ethical review process, should be developed in particular for participatory (action) research, where researchers work in partnership with communities. 9. When implementing these recommendations, the specific needs and implications for developing countries should be addressed.The Wonca executive committee has reviewed these recommendations and the supporting rationale for each. They plan to follow the recommendations, but to do so will require the support and cooperation of many individuals, organizations, and national governments around the world.

Skin infections and ageing

Elderly individuals have an increased susceptibility to skin infections due to age-related anatomical, physiological and environmental factors. The types of organisms that cause primary skin and soft tissue infections are diverse, and include bacterial, viral and fungal pathogens as well as parasites. In the elderly, these infections and infestations may present with atypical signs and symptoms or may complicate underlying chronic skin disorders. Clinical features, investigations and management of the following important and common skin infections are described in more detail: cellulitis, erysipelas, necrotizing fasciitis, impetigo, folliculitis, furunculosis and carbunculosis, erythrasma, herpes zoster and postherpetic neuralgia, herpes simplex, warts, molluscum contagiosum, dermatophytosis of the skin, hair and nails, candidiasis, and scabies. Treatment should be based on the results of the appropriate diagnostic tests. Correct diagnosis and therapy of skin infections lead to satisfactory outcome in the majority of elderly patients.

Interventions for impetigo

BACKGROUND

Impetigo is a common superficial bacterial skin infection, most frequently encountered in children. There is no standard therapy and guidelines for treatment differ widely. Treatment options include many different oral and topical antibiotics as well as disinfectants.

OBJECTIVES

To assess the effects of treatments for impetigo, including waiting for natural resolution.

SEARCH STRATEGY

We searched the Skin Group Specialised Trials Register (March 2002), Cochrane Central Register of Controlled Trials (CENTRAL, Issue 1 2002), the National Research Register (2002), MEDLINE (from 1966 to January 2003), EMBASE (from 1980 to March 2000) and LILACS (November 2001). We handsearched the Yearbook of Dermatology (1938-1966), the Yearbook of Drug Therapy (1949-1966), used reference lists of articles and contacted pharmaceutical companies.

SELECTION CRITERIA

Randomised controlled trials of treatments for non-bullous and bullous, primary and secondary impetigo.

DATA COLLECTION AND ANALYSIS

All steps in data collection were done by two independent reviewers. We performed quality assessments and data collection in two separate stages.

MAIN RESULTS

We included 57 trials including 3533 participants in total which studied 20 different oral and 18 different topical treatments. CURE OR IMPROVEMENT: Topical antibiotics showed better cure rates than placebo (pooled odds ratio (OR) 6.49, 95% confidence interval (CI) 3.93 to 10.73), and no topical antibiotic was superior (pooled OR of mupirocin versus fusidic acid 1.76, 95% CI 0.69 to 2.16). Topical mupirocin was superior to oral erythromycin (pooled OR 1.22, 95% CI 1.05 to 2.97). In most other comparisons, topical and oral antibiotics did not show significantly different cure rates, nor did most trials comparing oral antibiotics. Penicillin was inferior to erythromycin and cloxacillin and there is little evidence that using disinfectant solutions improves impetigo.

SIDE EFFECTS

The reported number of side effects was low. Oral antibiotic treatment caused more side effects, especially gastrointestinal ones, than topical treatment.

REVIEWERS' CONCLUSIONS

Data on the natural course of impetigo are lacking. Placebo controlled trials are scarce. There is little evidence about the value of disinfecting measures. There is good evidence that topical mupirocin and topical fusidic acid are equally, or more effective than oral treatment for people with limited disease. It is unclear if oral antibiotics are superior to topical antibiotics for people with extensive impetigo. Fusidic acid and mupirocin are of similar efficacy. Penicillin was not as effective as most other antibiotics. Resistance patterns against antibiotics change and should be taken into account in the choice of therapy.

Fusidic acid resistance in Staphylococcus aureus

This review summarises current knowledge of the microbiological and clinical aspects of fusidic acid resistance in Staphylococcus aureus, and makes recommendations about fusidic acid prescribing and further research.

Severity of nonbullous Staphylococcus aureus impetigo in children is associated with strains harboring genetic markers for exfoliative toxin B, Panton-Valentine leukocidin, and the multidrug resistance plasmid pSK41

Nonbullous impetigo is a common skin infection in children and is frequently caused by Staphylococcus aureus. Staphylococcal toxins and especially exfoliative toxin A are known mediators of bullous impetigo in children. It is not known whether this is also true for nonbullous impetigo. We set out to analyze clonality among clinical isolates of S. aureus from children with nonbullous impetigo living in a restricted geographical area in The Netherlands. We investigated whether staphylococcal nasal carriage and the nature of the staphylococcal strains were associated with the severity and course of impetigo. Bacterial isolates were obtained from the noses and wounds of children suffering from impetigo. Strains were genetically characterized by pulsed-field gel electrophoresis-mediated typing and binary typing, which was also used to assess toxin gene content. In addition, a detailed clinical questionnaire was filled in by each of the participating patients. Staphylococcal nasal carriage seems to predispose the patients to the development of impetigo, and 34% of infections diagnosed in the Rotterdam area are caused by one clonal type of S. aureus. The S. aureus strains harbor the exfoliative toxin B (ETB) gene as a specific virulence factor. In particular, the numbers (P = 0.002) and sizes (P < 0.001) of the lesions were increased in patients infected with an ETB-positive strain. Additional predictors of disease severity and development could be identified. The presence of a staphylococcal plasmid encoding multiple antibiotic resistance traits, as detected by binary typing, was associated with a reduction in the cure rate. Our results recognize that a combination of staphylococcal virulence and resistance genes rather than a single gene determines the development and course of nonbullous impetigo. The identification of these microbial genetic markers, which are predictive of the severity and the course of the disease, will facilitate guided individualized antimicrobial therapy in the future.

A systematic review and meta-analysis of treatments for impetigo

BACKGROUND

Impetigo is a common clinical problem seen in general practice. Uncertainty exists as to the most effective treatment, or indeed if treatment is necessary.

AIM

To determine the most effective treatment for impetigo in a systemically well patient.

DESIGN OF STUDY

Systematic review and meta-analysis.

METHOD

Databases were searched for relevant studies. The Cochrane highly sensitive randomised controlled trial (RCT) search string was employed and combined with the word 'impetigo' as the MeSH term and keyword. The bibliographies of relevant articles were searched for additional references. RCTs that were either double- or observer-blind, and involved systemically well patients of any age in either primary or secondary care settings, were included. Studies that selected patients on the basis of skin swab results were excluded, as were studies that were not in English. Cure or improvement of impetigo reported at seven to 14 days from start of treatment was the primary outcome measure. Meta-analysis was performed on homogeneous studies.

RESULTS

Three hundred and fifty-nine studies were identified, of which 16 met the inclusion criteria. Meta-analysis demonstrated that topical antibiotics are more effective than placebo (odds ratio [OR] = 2.69, 95% confidence interval [CI] = 1.49 to 4.86). There is weak evidence for the superiority of topical antibiotics over some oral antibiotics, such as erythromycin (OR = 0.48, 95% CI = 0.23 to 1.00). There is no significant difference between the effects of mupirocin and fusidic acid (OR = 1.76, 95% CI = 0.77 to 4.03).

CONCLUSION

This review found limited high-quality evidence to inform the treatment of impetigo. From that which is available, we would recommend the use of a topical antibiotic for a period of seven days in a systemically well patient with limited disease. Further research is needed on the role of flucloxacillin and non-antibiotic treatments for impetigo.

7: Soft tissue, bone and joint infections

Soft tissue infections are common and usually respond rapidly to oral antibiotics; if empirical therapy fails then exposure to unusual organisms should be considered. Septic arthritis requires early recognition, identification of the infecting pathogen and urgent joint washout to prevent irreversible cartilage and bone destruction. Prosthetic joint infection is uncommon but has high morbidity; the best outcomes are achieved with removal of the prosthesis and replacement after at least six weeks of antibiotic therapy. Osteomyelitis often complicates diabetic foot infection with ulceration and is rarely cured by antibiotics alone; early surgical intervention achieves the best outcome.