Community-associated methicillin-resistant Staphylococcus aureus is prevalent in wounds of community-based injection drug users

Recurring Severe Injection-Related Infections in People Who Inject Drugs and the Need for Safe Injection Sites in Madrid, Spain

BACKGROUND

An estimated 58 749 people with opioid use disorder engaged in opioid agonist therapy (OAT) in 1132 centers in Spain during 2017. We aimed to calculate the incidence of severe injection-related infections in people who inject drugs (PWID) engaged in OAT in harm reduction settings without a safe consumption space.

METHODS

A retrospective cohort study was performed in PWID engaged in OAT and in a mobile harm reduction unit to quantify admissions to a referral hospital for any severe injection-related infections between 1 January 2016 and 31 December 2019. A Cox proportional hazard regression analysis was used to assess factors associated with any severe injection-related infection.

RESULTS

Two hundred thirty-seven PWID who engaged in OAT were included in the study. After a median follow-up of 5.5 months (interquartile range [IQR], 1.3-22.7 months), a total of 104 episodes of severe injection-related infections occurred among 56 individuals, and admission due to a second event occurred in 35.7% of this same group. The incidence density of any type of severe injection-related infection was 26.8 (95% confidence interval [CI], 20.2-34.8) episodes per 100 person-years, and the incidence density of complicated skin and soft tissue infections that required hospital admission was 20.4 (95% CI, 15.0-27.3) episodes per 100 person-years. Fifty-six (53.8%) of all the episodes were patient-directed discharge (PDD), and people who had 2 or more hospital admissions had a higher PDD frequency.

CONCLUSIONS

Severe injection-related infections remain highly prevalent among PWID cared for in a harm reduction setting without a safe consumption space. PDD was more frequent among higher-risk individuals who presented 2 or more hospital readmissions.

Advantages of Outpatient Treatment with Long-Acting Lipoglycopeptides for Serious Gram-Positive Infections: A Review

Treatment of serious gram-positive infections presents multiple challenges. Treatment often results in prolonged hospitalization for administration of intravenous antimicrobials and presents an inefficient use of hospital resources. Prolonged hospitalization is typically also unfavorable to patient preferences and potentially subjects patients to additional health care-associated complications. Current strategies of transition to outpatient settings-outpatient parenteral antimicrobial therapy and use of oral antibiotics-often do not adequately serve vulnerable populations for whom there is often no alternative to inpatient therapy. Specifically, people who use drugs, those who cannot reliably adhere to unsupervised treatment (poor mental or physical health), people with complicating life circumstances (e.g., homelessness, incarceration, rural location), and those with inadequate health insurance remain hospitalized for weeks longer than persons without such conditions. We suspected that long-acting lipoglycopeptides (laLGP), such as dalbavancin and oritavancin, may be useful in patient transitions to outpatient settings. Thus, we conducted a search of the peer-reviewed literature using the PubMed, Google Scholar, and MEDLINE databases. Based on accumulating literature, it appears that laLGPs offer a reliable alternative therapeutic strategy that addresses many of the personal and systemic barriers to the traditional transitioning approaches. Current evidence also suggests that these agents may be cost-effective from patient, payer, and hospital perspectives. Barriers to broader use of laLGPs include, among others, a relative lack of prospective data regarding efficacy in serious infections, a narrow United States Food and Drug Administration-approved indication restricted to only acute bacterial skin and skin structure infections, and lack of reimbursement infrastructure for inpatient settings.

Prevalence, risk factors, phenotypic and molecular characteristics for Staphylococcus aureus carriage in community-based drug users in Guangzhou, China

Background

Staphylococcus aureus (S. aureus), particularly methicillin-resistant Staphylococcus aureus (MRSA), remains the predominant cause of infections in drug users. This cross-sectional study aims to elucidate the prevalence, risk factors, phenotypic and molecular characteristics of S. aureus carriage among community-based drug users.

Methods

All eligible drug users, with both injection and non-injection route of drug administration, were asked to complete questionnaires and collect nasal swabs by trained personal during the period between May and December 2017 in Guangzhou, China. Swabs were processed for identification of S. aureus. Antimicrobial susceptibility test and polymerase chain reaction assays were used to detect phenotypic and molecular characteristics for identified isolates. Univariate and multivariate logistic regression analyses were used to assess risk factors for S. aureus carriage.

Results

Overall, 353 drug users were included in the study and the prevalence of S. aureus carriage was 15.01% (53/353). The prevalence of MRSA carriage was 6.80% (24/353). Cohabitation was a risk factor for S. aureus (adjusted OR = 8.80, 95% CI: 1.89–40.99). The proportion of multidrug resistance was 54.72% for S. aureus isolates and most of these isolates were resistant to penicillin, erythromycin and clindamycin. Seventeen MRSA isolates were multidrug resistant. The results of clonal complexes (CCs) and sequence types (STs) for S. aureus were diverse. The three predominant types for CCs were CC5 (64.15%, 34/53), CC59 (11.32%, 6/53), and CC7 (7.55%, 4/53); and for STs were ST188 (20.75%, 11/53), ST5 (11.32%, 6/53), and ST59 (11.32%, 6/53).

Conclusion

The prevalence of S. aureus nasal carriage was lower while the prevalence of MRSA carriage was moderate compared to previous studies. Phenotypic and molecular characteristics of S. aureus isolates, particularly MRSA isolates, revealed high proportions of antibiotic resistance, indicating the existence of cross-circulation, and implying high opportunity of virulence-related diseases. Decolonization and antibiotic stewardship might be implemented for drug users with MRSA carriage.

Long-Acting Lipoglycopeptides: "Lineless Antibiotics" for Serious Infections in Persons Who Use Drugs

Background

Injection drug use is associated with serious infections. Due to challenges with medical management of addiction, relapses and additional infections are common. Persons who use drugs (PWUD) are more likely to leave against medical advice before completing treatment, which could result in treatment failure. Prolonged intravenous (IV) antimicrobial therapy in PWUD may be complicated by concern for IV catheter misuse, sometimes requiring prolonged hospitalization. Ideal alternatives would provide the following: (1) high success rate; (2) reduced rate of medical complications; (3) improved safety profiles; and (4) improved cost-effectiveness. Long-acting lipoglycopeptides present such opportunity for treatment of serious Gram-positive infections.

Methods

We performed a system-wide, retrospective analysis of adults admitted to University of Colorado Health from September 2015 to June 2018 and treated with dalbavancin or oritavancin based on clinical judgment of their treating physicians.

Results

Fifty-six patients met inclusion criteria (17 PWUD vs 39 non-PWUD). The PWUD group were younger, healthier by Charlson comorbidity index, more likely insured by Medicaid, and admitted for conditions requiring longer treatment. Ten patients were lost to follow-up. Of the patients with follow-up, clinical failure was met in 1 PWUD patient (6%) and 6 non-PWUD patients (15%) (P = .413). The median hospital length-of-stay reduction was 20 days (interquartile range [IQR], 10–30 days) in PWUD vs 11 days (IQR, 9–14 days) in non-PWUD; P = .133. Estimated median savings were $40 455.08 (IQR, $20 900.00–$62 700.00) in PWUD vs $19 555.08 (IQR, $15 375.08–$23 735.08) in non-PWUD; P = .065.

Conclusions

Long-acting lipoglycopeptides may be equally effective as standard-of-care, present a safety advantage, and secure earlier discharge and significant cost-savings.

Compliance to antibiotic guidelines leads to more appropriate use of antibiotics in skin and soft tissue infections in injecting drug users

Background: Knowledge about the treatment of skin and soft tissue infections in injecting drug users in countries with a low prevalence of antibiotic resistance is limited. We investigated bacterial antibiotic resistance and treatment of skin and soft tissue infections in Norwegian drug users. Methods: We performed a two year clinical cross-sectional observational study in a Norwegian hospital. Data were collected retrospectively from hospital records. We examined bacteriological findings and antibiotic resistance, and evaluated compliance to treatment guidelines and appropriateness of empirical antibiotic therapy relative to results of cultures and susceptibility testing. Descriptive and univariate analyses were performed. Results: Hundred and thirty-five injecting drug users were admitted with skin and soft tissue infection in the study period. Cultures were obtained from 103 (77%) abscesses and eight (24%) erysipelas and cellulitis, with bacterial growth in 80 (78%) and five (63%), respectively. Streptococci and staphylococci were the most prevalent bacteria, but methicillin-resistant Staphylococcus aureus was found in only one patient. Compliance to hospital antibiotic guidelines was 70%. Ninety-one per cent of patients in the compliant and 79% in the non-compliant group were given effective empirical antibiotics (p = .334). In the non-compliant group, significantly more patients received broad-spectrum empirical antibiotics (p < .001). In 30 cases where adjustment of antibiotic therapy was possible according to susceptibility testing, this was performed in only 14 cases. Conclusions: Bacteria and resistance patterns did not differ significantly from the skin and soft tissue infections in the general population in Norway. Compliance to antibiotic guidelines led to significantly less use of broad-spectrum antibiotics and to good bacterial coverage. General guidelines for treatment should be applied to injecting drug users with skin and soft tissue infections.

Caring for Patients With Opioid Use Disorder: What Clinicians Should Know About Comorbid Medical Conditions

Opioid use disorder (OUD) is a growing problem, with opioid‐involved overdose deaths quadrupling since 1999 in the United States. This article reviews comorbid medical conditions related to OUD, starting with complications of behaviors associated with opioid use (e.g., injection drug use), followed by conditions stemming from the direct effects of opioids (e.g., hypogonadism). HIV and hepatitis C virus (HCV) are common infections in people with OUD, and treatment for these conditions can be safely provided regardless of ongoing substance use. Complications of drug injection, such as HIV, HCV, skin and soft tissue infections, and infective endocarditis, may be prevented through provision of sterile syringes and supervised injection facilities. Rare, life‐threatening bacterial infections may present with signs and symptoms that mimic intoxication, such as malaise or stupor, and should be assessed in patients with fever or positive blood cultures. In addition, chronic opioid exposure can lead to hypogonadism, opioid‐induced hyperalgesia, sleep‐disordered breathing, and potentially increased risk of cardiovascular disease and neurocognitive impairment. Pharmacotherapies for OUD (buprenorphine, methadone, and naltrexone) are safe and effective and their adverse opioid effects can be managed in clinical practice. Awareness of OUD‐associated medical conditions and their treatments is an important step in improving the health and wellness of people with OUD.

Use of on-site detoxification services co-located with a supervised injection facility

OBJECTIVES

Supervised injection facilities (SIFs) are increasingly being implemented worldwide in response to the harms associated with injection drug use. Although SIFs have been shown to promote engagement of people who use injection drugs (PWID) with external health services, little is known about the potential of co-locating on-site detoxification services with SIFs. The aim of this study was to characterize use of detoxification services co-located at Insite, North America's first SIF, among PWID in Vancouver, Canada.

METHODS

Data were derived from two prospective cohorts of PWID in Vancouver, Canada between November 2010 and December 2012. Using multivariable generalized estimating equation logistic regression, we identified factors independently associated with reporting use of detoxification services at the SIF.

RESULTS

Among 1316 PWID, 147 (11.2%) reported enrolling in detoxification services co-located with the SIF at least once during the two year study period. In multivariable analyses, after adjustment for other potential cofounders, factors independently and positively associated with use of this service included residence<5 blocks from the SIF (Adjusted Odds Ratio [AOR]=1.70), enrollment in methadone maintenance therapy (AOR=1.90), public injection (AOR=1.53), binge injection (AOR=1.93), recent overdose (AOR=1.90) and frequent SIF use (AOR=8.15) (all p<0.05).

DISCUSSION

Use of on-site detoxification services offered at the SIF was common among PWID and associated with frequent SIF use and various markers of vulnerability and drug-related risk. These findings highlight the potential role of SIFs as a point of access to detoxification services for high-risk PWID. Future studies should examine if co-location leads to higher uptake of addiction services in comparison to services that create geographic or other obstacles.

Drug Use Is Associated With Purulent Skin and Soft Tissue Infections in a Large Urban Jail: 2011-2015

Background

Skin and soft tissue infections (SSTIs) are a common problem in jails in the United States. This study aimed to identify factors associated with purulent SSTIs in the New York City jail system.

Methods

We conducted a case-control study of purulent SSTIs at the New York City jail. Cases were matched to controls by visit date to the jail’s urgent care clinic. Bivariate and multivariable analyses were conducted using conditional logistic regression.

Results

From April 2011 to April 2015, 1010 cases of SSTIs were identified and matched to 1010 controls. In multivariable analyses, report upon entry to jail of current injection drug use (odds ratio [OR], 2.76; 95% confidence interval [CI], 1.77–4.31), current snorting of drugs (OR, 1.50; 95% CI, 1.12–2.00), current heroin use (OR, 1.53; 95% CI, 1.08–2.17), current cocaine use (OR, 1.76; 95% CI, 1.18–2.65), and antibiotic use within the previous 6 months (OR, 4.05; 95% CI, 2.98–5.49) were significantly associated with SSTI diagnosis.

Conclusions

Skin and soft tissue infections were strongly associated with a history of drug use at jail entry. Targeting intravenous drug use may be a preventive strategy for SSTIs in this population. Strategies such as harm reduction programs may be investigated.

Reduction in hospital-associated methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus with daily chlorhexidine gluconate bathing for medical inpatients

BACKGROUND

Daily bathing with chlorhexidine gluconate (CHG) is increasingly used in intensive care units to prevent hospital-associated infections, but limited evidence exists for noncritical care settings.

METHODS

A prospective crossover study was conducted on 4 medical inpatient units in an urban, academic Canadian hospital from May 1, 2014-August 10, 2015. Intervention units used CHG over a 7-month period, including a 1-month wash-in phase, while control units used nonmedicated soap and water bathing. Rates of hospital-associated methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) colonization or infection were the primary end point. Hospital-associated S. aureus were investigated for CHG resistance with a qacA/B and smr polymerase chain reaction (PCR) and agar dilution.

RESULTS

Compliance with daily CHG bathing was 58%. Hospital-associated MRSA and VRE was decreased by 55% (5.1 vs 11.4 cases per 10,000 inpatient days, P = .04) and 36% (23.2 vs 36.0 cases per 10,000 inpatient days, P = .03), respectively, compared with control cohorts. There was no significant difference in rates of hospital-associated Clostridium difficile. Chlorhexidine resistance testing identified 1 isolate with an elevated minimum inhibitory concentration (8 µg/mL), but it was PCR negative.

CONCLUSIONS

This prospective pragmatic study to assess daily bathing for CHG on inpatient medical units was effective in reducing hospital-associated MRSA and VRE. A critical component of CHG bathing on medical units is sustained and appropriate application, which can be a challenge to accurately assess and needs to be considered before systematic implementation.

Managing skin and soft-tissue infection and nosocomial pneumonia caused by MRSA: a 2014 follow-up survey

As a follow-up to our 2009 survey, in order to explore opinion and practice on the epidemiology and management of meticillin-resistant Staphylococcus aureus (MRSA) in Europe, we conducted a second survey to elicit current opinions on this topic, particularly around antibiotic choice, dose, duration and route of administration. We also aimed to further understand how the management of MRSA has evolved in Europe during the past 5 years. Members of an expert panel of infectious diseases specialists convened in London (UK) in January 2014 to identify and discuss key issues in the management of MRSA. Following this meeting, a survey was developed comprising 36 questions covering a wide range of topics on MRSA complicated skin and soft-tissue infection and nosocomial pneumonia management. The survey instrument, a web-based questionnaire, was sent to the International Society of Chemotherapy for distribution to registered European infection societies and their members. This article reports the survey results from the European respondents. At the time of the original survey, the epidemiology of MRSA varied significantly across Europe and there were differing views on best practice. The current findings suggest that the epidemiology of healthcare-associated MRSA in Europe is, if anything, even more polarised, whilst community-acquired MRSA has become much more common. However, there now appears to be a much greater knowledge of current treatment/management options, and antimicrobial stewardship has moved forward considerably in the 5 years since the last survey.

Molecular epidemiology and antimicrobial susceptibility profiles of methicillin-resistant Staphylococcus aureus blood culture isolates: results of the Quebec Provincial Surveillance Programme

The objectives of this study were to characterize methicillin-resistant Staphylococcus aureus (MRSA) blood culture isolates and to determine their relative importance in both nosocomial and community-acquired infections. A total of 535 MRSA blood culture isolates were analysed. In vitro susceptibility to 14 agents was determined. The genes nuc, mecA and coding for PVL toxin were identified by PCR. All isolates were characterized by PFGE or spa typing to assess their genomic relationships. Most MRSA isolates were retrieved from nosocomial bloodstream infections (474, 89%) and were of the CMRSA2 genotype. Healthcare-associated (HA)-MRSA bloodstream infections were associated with older age (70-89 years, P = 0·002) and most often secondary to central line infections (P = 0·005). Among MRSA strains associated with community-acquired (CA)-MRSA, 28·8% were isolated in intravenous drug users. CA-MRSA genotypes were more frequently found in young adults (20-39 years, P < 0·0001) with skin/soft tissue as the primary sources of infection (P = 0·006). CMRSA10 genotype was the predominant CA-MRSA strain. All MRSA isolates were susceptible to doxycycline, tigecycline, trimethoprim/sulfamethoxazole and vancomycin. Both the presence of the genes coding for PVL toxin (89·8%) and susceptibility to clindamycin (86·5%) were predictive of CA-MRSA genotypes. Whereas in the USA, HA-MRSA have been replaced by USA300 (CMRSA10) clone as the predominant MRSA strain type in positive blood cultures from hospitalized patients, this phenomenon has not been observed in the province of Quebec.

Adverse health consequences of performance-enhancing drugs: an Endocrine Society scientific statement

Despite the high prevalence of performance-enhancing drug (PED) use, media attention has focused almost entirely on PED use by elite athletes to illicitly gain a competitive advantage in sports, and not on the health risks of PEDs. There is a widespread misperception that PED use is safe or that adverse effects are manageable. In reality, the vast majority of PED users are not athletes but rather nonathlete weightlifters, and the adverse health effects of PED use are greatly underappreciated. This scientific statement synthesizes available information on the medical consequences of PED use, identifies gaps in knowledge, and aims to focus the attention of the medical community and policymakers on PED use as an important public health problem. PED users frequently consume highly supraphysiologic doses of PEDs, combine them with other PEDs and/or other classical drugs of abuse, and display additional associated risk factors. PED use has been linked to an increased risk of death and a wide variety of cardiovascular, psychiatric, metabolic, endocrine, neurologic, infectious, hepatic, renal, and musculoskeletal disorders. Because randomized trials cannot ethically duplicate the large doses of PEDs and the many factors associated with PED use, we need observational studies to collect valid outcome data on the health risks associated with PEDs. In addition, we need studies regarding the prevalence of PED use, the mechanisms by which PEDs exert their adverse health effects, and the interactive effects of PEDs with sports injuries and other high-risk behaviors. We also need randomized trials to assess therapeutic interventions for treating the adverse effects of PEDs, such as the anabolic-androgen steroid withdrawal syndrome. Finally, we need to raise public awareness of the serious health consequences of PEDs.

Community-associated methicillin-resistant Staphylococcus aureus necrotizing pneumonia without evidence of antecedent viral upper respiratory infection

BACKGROUND

USA300 community-associated (CA) methicillin-resistant Staphylococcus aureus (MRSA) strains causing necrotizing pneumonia have been reported in association with antecedent viral upper respiratory tract infections (URI).

METHODS

A case series of necrotizing pneumonia presenting as a primary or coprimary infection, secondary to CA-MRSA without evidence of antecedent viral URI, is presented. Cases were identified through the infectious diseases consultation service records. Clinical and radiographic data were collected by chart review and electronic records. MRSA strains were isolated from sputum, bronchoalveolar lavage, pleural fluid or blood cultures and confirmed using standard laboratory procedures. MRSA strains were characterized by susceptibility testing, pulsed-field gel electrophoresis, spa typing, agr typing and multilocus sequence typing. Testing for respiratory viruses was performed by appropriate serological testing of banked sera, or nucleic acid testing of nasopharyngeal or bronchoalveloar lavage specimens.

RESULTS

Ten patients who presented or copresented with CA necrotizing pneumonia secondary to CA-MRSA from April 2004 to October 2011 were identified. The median length of stay was 22.5 days. Mortality was 20.0%. Classical risk factors for CA-MRSA were identified in seven of 10 (70.0%) cases. Chest tube placement occurred in seven of 10 patients with empyema. None of the patients had historical evidence of antecedent URI. In eight of 10 patients, serological or nucleic acid testing testing revealed no evidence of acute viral coinfection. Eight strains were CMRSA-10 (USA300). The remaining two strains were a USA300 genetically related strain and a USA1100 strain.

CONCLUSION

Pneumonia secondary to CA-MRSA can occur in the absence of an antecedent URI. Infections due to CA-MRSA are associated with significant morbidity and mortality. Clinicians need to have an awareness of this clinical entity, particularly in patients who are in risk groups that predispose to exposure to this bacterium.

Carriage of methicillin-resistant Staphylococcus aureus by wild urban Norway rats (Rattus norvegicus)

Methicillin-resistant Staphylococcus aureus (MRSA) is an important cause of multi-drug-resistant infections in people, particularly indigent populations. MRSA can be transmitted between people and domestic animals, but the potential for transmission between people and commensal pests, particularly rodents, had not been investigated. The objective of this study was to identify the presence and characterize the ecology of MRSA in rats (Rattus spp.) from in an impoverished, inner-city neighborhood. Oropharyngeal swabs were collected from rats trapped in 33 city blocks and one location within the adjacent port. Bacterial culture was performed and MRSA isolates were characterized using a variety of methods, including whole-genome sequencing (WGS). The ecology of MRSA in rats was described using phylogenetic analysis, geospatial analysis, and generalized linear mixed models. MRSA was identified 22 of 637 (3.5%) rats tested, although prevalence varied from 0 – 50% among blocks. Isolates belonged to 4 clusters according to WGS, with the largest cluster (n = 10) containing isolates that were genetically indistinguishable from community-acquired USA300 MRSA strains isolated from people within the study area. MRSA strains demonstrated both geographic clustering and dispersion. The odds of an individual rat carrying MRSA increased with increased body fat (OR = 2.53, 95% CI = 1.33 – 4.82), and in the winter (OR = 5.29, 95% CI = 1.04 – 26.85) and spring (OR = 5.50, 95% CI = 1.10 – 27.58) compared to the fall. The results show that urban rats carried the same MRSA lineages occurring in local human and/or animal populations, supporting recent transmission from external sources. MRSA carriage was influenced by season, most likely as a result of temporal variation in rat behavior and rat-human interactions.

Algorithm to reduce unnecessary isolation days in patients with a history of colonization by antimicrobial-resistant organisms

To determine the need of isolation precautions upon admission, we created and tested an algorithm based on a total of 474 patients with a history of carriage of an antibiotic-resistant organism. Using the algorithm upon patient admission reduced unnecessary isolations by almost 60% while maintaining a high sensitivity to predict persisting antibiotic-resistant organism colonization.

Reduction in community-onset methicillin-resistant Staphylococcus aureus rates in an urban Canadian hospital setting

Community-onset methicillin resistant Staphylococcus aureus (CO-MRSA) became a prominent cause of infection in North America in 2003, with a peak in the epidemic noted by multiple groups in the USA between 2005 and 2007. We reviewed rates of MRSA in two hospitals in Vancouver, Canada, to observe changes in epidemiology from 2003 to 2011. Episodes of emergency department (ED) MRSA bacteraemia and wounds were extracted from the laboratory database, with rates calculated per 10,000 ED visits. All cases were assumed to be community onset, as they were diagnosed in the ED. A peak in ED MRSA bacteraemias occurred in 2005, at 7·8/10,000 ED visits. By 2011, rates of ED bacteraemia declined significantly to 3·3/10,000 ED visits (P<or=0·03). MRSA wound rates peaked at 82·2 cases/10,000 ED visits in 2007 with a subsequent significant decline to 34·3 cases in 2011 (P=0·04). We have demonstrated a significant decline in CO-MRSA within our population, consistent with reports from the USA, suggesting a substantial change in the epidemiology of CO-MRSA in certain North American cities.

Skin and needle hygiene intervention for injection drug users: results from a randomized, controlled Stage I pilot trial

A new skin and needle hygiene intervention, designed to reduce high-risk injection practices associated with bacterial and viral infections, was tested in a pilot, randomized controlled trial. Participants included 48 active heroin injectors recruited through street outreach and randomized to either a 2-session intervention or an assessment-only condition (AO) and followed up for 6 months. The primary outcome was skin- and needle-cleaning behavioral skills measured by videotaped demonstration. Secondary outcomes were high-risk injection practices, intramuscular injection, and bacterial infections. Intervention participants had greater improvements on the skin (d = 1.00) and needle-cleaning demonstrations (d = .52) and larger reductions in high-risk injection practices (d = .32) and intramuscular injection (d = .29), with a lower incidence rate of bacterial infections (hazard ratio = .80), at 6 months compared with AO. The new intervention appears feasible and promising as a brief intervention to reduce bacterial and viral risks associated with drug injection.

Screening for methicillin-resistant Staphylococcus aureus (MRSA) in community-recruited injection drug users: are throat swabs necessary?

We examined and described colonization of MRSA in the anterior nares and throat from 184 community-recruited injection drug users. Thirty-seven (20%) were positive for MRSA: most (34, 92%) were carriers in the nares; while only three (8%) were carriers detected by throat swabs alone. The majority (29, 78%) of MRSA isolates were PVL positive.

Community-associated methicillin-resistant Staphylococcus aureus infection in Portugal

Methicillin-resistant Staphylococcus aureus (MRSA) has recently emerged as a cause of community-acquired infections among individuals without risk factors. Community-associated MRSA (CA-MRSA) appears to be more virulent, causing superficial mild skin and soft tissue infections to severe necrotizing fasciitis, and in rare cases, pneumonia. Community-associated MRSA was first reported in Australia in the early 80s, after almost two decades in the USA, and then in several countries in Europe, Asia and South America. No data exists in Portugal. We report the first case of CA-MRSA infection in Portugal, in a young adult with severe necrotizing pneumonia, complicated with bilateral empyema and respiratory failure.

Co-blockade of mecR1/blaR1 signal pathway to restore antibiotic susceptibility in clinical isolates of methicillin-resistant Staphylococcus aureus

INTRODUCTION

Methicillin-resistant Staphylococcus aureus (MRSA) is caused by the production of low-affinity penicillin-binding protein 2a and β-lactamases, which are encoded by mecA and blaZ, respectively. Expressions of the two key genes are mutually regulated by MecI and BlaI. The aim of this study was to design specific anti-mecR1 and anti-blaR1 deoxyribozymes and identify the restoration of susceptibility in MRSA isolates with mecI or blaI or no deletions by interfering with the mutual regulation of mecA and blaZ.

MATERIAL AND METHODS

Specific deoxyribozymes were designed by using the program RNA structure 4.6. RNA substrates were obtained by transcription in vitro and used to assess the target cleavage of DNAzymes. Transcription of mecR1-mecA and blaR1-blaZ was analysed by real time RT-PCR. The susceptibility of MRSA was tested.

RESULTS

Specific deoxyribozymes showed efficient catalytic activity to each own substrate mecR1 or blaR1 in vitro and caused the reduction of mecR1 and blaR1 transcription in vivo. Furthermore, simultaneous administration of two DNAzymes to knockdown mecR1 and blaR1 resulted in increased susceptibility of all MRSA strains tested in this study.

CONCLUSIONS

These results demonstrated that combined use of the two specific phosphorothioate deoxyribozymes could be a viable and promising strategy to restore the susceptibility of almost all MRSA clinical isolates.

Cutaneous diphtheria in the urban poor population of Vancouver, British Columbia, Canada: a 10-year review

Between 1998 and 2007, records from 33 patients with cutaneous diphtheria from Vancouver's inner city were reviewed. Cases were associated with injection drug use and poverty. Coinfections with Staphylococcus aureus, Streptococcus pyogenes, and Arcanobacterium haemolyticum occurred. Corynebacterium diphtheriae is endemic in Vancouver's urban core, with strains of multilocus sequence type (MLST) 76 predominating.

Shooting up: the interface of microbial infections and drug abuse

Illicit drug control has been on the global agenda for more than a century. Infections have long been recognized as one of the most serious complications of drug abuse. Drug users are susceptible to pulmonary, endovascular, skin and soft tissue, bone and joint, and sexually transmitted infections caused by a wide range of bacterial, viral, fungal and protozoal pathogens. In addition, injection drug users are at increased risk for parenterally acquired infections such as human immunodeficiency virus, hepatitis B virus, hepatitis C virus, tetanus and malaria. Factors related to drug use, such as unsterile injection practices, contaminated drug paraphernalia and drug adulterants, increase the exposure to microbial pathogens. Illicit drugs also affect several components of the complex immune system and thus modulate host immunity. In addition, lifestyle practices such as multiple sexual partners, overcrowded housing arrangements and malnutrition serve as co-factors in increasing the risk of infection. In this review we present an overview of the unique aspects of microbial pathogenesis, immune modulation and common infections associated with drug use. We have restricted the definition of drug abuse to the use of illegal drugs (such as opiates, marijuana, cocaine, heroin and amphetamines), not including alcohol and nicotine.