Prevalence and antimicrobial-resistance of Pseudomonas aeruginosa in swimming pools and hot tubs

Evolving trends among Pseudomonas aeruginosa: a 12-year retrospective study from the United Arab Emirates

Introduction

Pseudomonas is a group of ubiquitous non-fermenting Gram-negative bacteria (NFGNB). Of the several species associated with humans, Pseudomonas aeruginosa (PA) can acclimate to diverse environments. The global frequency of PA infections is rising and is complicated by this organism's high intrinsic and acquired resistance to several clinically relevant antibiotics. Data on the epidemiology, levels, and trends of antimicrobial resistance of PA in clinical settings in the MENA/GCC region is scarce.

Methods

A retrospective 12-year analysis of 56,618 non-duplicate diagnostic Pseudomonas spp. from the United Arab Emirates (UAE) was conducted. Data was generated at 317 surveillance sites by routine patient care during 2010-2021, collected by trained personnel and reported by participating surveillance sites to the UAE National antimicrobial resistance (AMR) Surveillance program. Data analysis was conducted with WHONET (https://whonet.org/).

Results

Among the total isolates (N = 56,618), the majority were PA (95.6%). Data on nationality revealed 44.1% were UAE nationals. Most isolates were from soft tissue (55.7%), followed by respiratory tract (26.7%). PA was more commonly found among inpatients than among outpatients, followed by ICUs. PA showed a horizontal trend for resistance to fluoroquinolones, 3rd- and 4th-generation cephalosporins, and decreasing trends of resistance for aminoglycosides and meropenem. The highest percentage of multidrug resistant (MDR) isolates was reported in 2011 at 35.6%. As an overall trend, the percentage of MDR, extensively drug-resistant (XDR), and possible pandrug-resistant (PDR) isolates generally declined over the study period. Carbapenem-resistant PA (CRPA) were associated with a higher mortality (RR: 2.7), increased admission to ICU (RR: 2.3), and increased length of stay (LOS) (12 excess inpatient days per case), as compared to carbapenem-susceptible PA (CSPA).

Conclusion

The resistance trends in Pseudomonas species in the UAE indicated a decline in AMR and in percentages of Pseudomonas isolates with MDR and XDR profiles. The sustained Pseudomonas spp. circulation particularly in the hospital settings highlights the importance of surveillance techniques, infection control strategies, and stewardship to limit the continued dissemination. This data also shows that CRPA are associated with higher mortality, increased ICU admission rates, and a longer hospitalization, thus higher costs due to increased number of in-hospital and ICU days.

Environmental surveillance of Pseudomonas aeruginosa in recreational waters in tourist facilities of the Balearic Islands, Spain (2016-2019)

BACKGROUND

Pseudomonas aeruginosa is a major opportunistic human pathogen commonly connected with recreational water activities. Spain is a tourist destination where most of the establishments have swimming pool. Nevertheless, the prevalence of P. aeruginosa in public swimming pools in our country is unknown. This works aimed to survey the P. aeruginosa presence in tourist Spanish recreational waters.

METHOD

Tourist recreational water in hotels in the Balearic Islands were visited for four years (2016-2019). The levels of selected parameters were determined, and their correlation with P. aeruginosa contamination investigated.

RESULTS

We evaluated 11,014 samples from 254 facilities. Unacceptable levels of at least one legislated parameter were detected in 30.7% of cases, implicating closure in 15.9%, being P. aeruginosa the leading cause of closure. The prevalence of the pathogen was 14.2%, with lower presence in outer swimming pools. Disinfectant levels influence P. aeruginosa contamination, and bromine-maintained pools were more often contaminated than those treated with chlorine. Prevalence remained constant over the years, although it increased in 2019.

CONCLUSIONS

P. aeruginosa prevalence in our recreational waters is similar to other countries, and the contamination rates depend on the installations and type and disinfectant levels. Corrective measures are still needed to improve pathogen control.

Cu(II) assisted peroxymonosulfate for antibiotic resistant bacteria inactivation: A potential disinfection technology in swimming pool

Alternative disinfection technology to chlorination is required to control the risk of antibiotic resistance in swimming pools. In this study, copper ions (Cu(II)), which often exist in swimming pools as algicides, were used to activate peroxymonosulfate (PMS) for the inactivation of ampicillin-resistant E. coli. Cu(II) and PMS showed synergistic effects on E. coli inactivation in weak alkaline conditions, obtaining 3.4 log inactivation in 20 min with 10 μM Cu(II) and 100 μM PMS at pH 8.0. Quenching experiments indicated that radicals (i.e., OH and SO₄^-) were not the main disinfectors for E. coli inactivation. Based on the structure of Cu(II) and density functional theory calculations, the Cu(II)-PMS complex (Cu(H₂O)₅SO₅) was recommended as the active species for E. coli inactivation. Under the experimental conditions, the PMS concentration had a greater influence on E. coli inactivation than the Cu(II) concentration, possibly because increasing PMS concentration accelerates ligand exchange reaction and facilitates active species generation. By forming hypohalous acids, halogen ions could improve the disinfection efficiency of Cu(II)/PMS. The addition of HCO₃^- concentration (from 0 to 1.0 mM) and humic acid (0.5 and 1.5 mg/l) did not significantly inhibit the E. coli inactivation. The feasibility of adding PMS to waters containing Cu(II) for the inactivation of antibiotic-resistant bacteria was validated in actual swimming pool waters, where 4.7 log inactivation of E. coli was achieved in 60 min.

Zwitterion and N-halamine functionalized cotton wound dressing with enhanced antifouling, antibacterial, and hemostatic properties

With emerging needs of wound care management, a multi-functional wound dressing is needed. To prevent infection and reduce patient suffering, antibacterial efficacy against a broad-spectrum of bacteria plus robust antifouling are among the most preferred properties. In this study, a wound dressing was created with antibacterial and anti-fouling capabilities is presented. The approaches used a synthesized tri-functional copolymer comprised of an N-halamine precursor moiety, a marine-inspired surface binding dopamine moiety, and a zwitterionic anti-adhesion moiety bonded onto a commercial cotton gauze. The resulting HaloCare™ wound dressing demonstrated >99.99 % inactivation within 5 min against E. coli and a panel of ESKAPE pathogens plus achieved 98.77 % reduction of non-specific protein binding. HaloCare was also shown to be compatible with hemostatic agents without impacting hemostatic efficacy. HaloCare shows great potential particularly in traumatic injury events as an infection preventing and hemostatic wound management system.

Solution-Based Ultra-Sensitive Surface-Enhanced Raman Scattering Detection of the Toxin Bacterial Biomarker Pyocyanin in Biological Fluids Using Sharp-Branched Gold Nanostars

There is a critical need for sensitive rapid point-of-care detection of bacterial infection biomarkers in complex biological fluids with minimal sample preparation, which can improve early-stage diagnosis and prevent several bacterial infections and fatal diseases. A solution-based surface-enhanced Raman scattering (SERS) detection platform has long been sought after for low cost, rapid, and on-site detection of analyte molecules, but current methods still exhibit poor sensitivity. In this study, we have tuned the morphology of the surfactant-free gold nanostars (GNSs) to achieve sharp protruding spikes for maximum SERS enhancement. We have controlled the GNS spike morphologies and optimized SERS performance in the solution phase using para-mercaptobenzoic acid as an SERS probe. To illustrate the potential for point-of-care applications, we have utilized a portable Raman instrument for measurements. For pathogenic agent sensing applications, we demonstrated rapid and sensitive detection of the toxin biomarker pyocyanin (PYO) used as the bacterial biomarker model system. Pyocyanin is a toxic compound produced and secreted by the common water-borne Gram-negative bacterium Pseudomonas aeruginosa, a pathogen known for advanced antibiotic resistance and association with serious diseases such as ventilator-associated pneumonia and cystic fibrosis. The limit of detection (LOD) achieved for PYO was 0.05 nM using sharp branched GNSs. Furthermore, as a proof of strategy, this SERS detection of PYO was performed directly in drinking water, human saliva, and human urine without any sample treatment pre-purification, achieving an LOD of 0.05 nM for drinking water and 0.4 nM for human saliva and urine. This work provides a proof-of-principle demonstration for the high sensitivity detection of the bacterial toxin biomarker with minimal sample preparation: the "mix and detect" detection of the GNS platform is simple, robust, and rapid, taking only 1-2 min for each measurement. Overall, our SERS detection platform shows great potential for point-of-need sensing and point-of-care diagnostics in biological fluids.

Molecular epidemiology of antimicrobial-resistant Pseudomonas aeruginosa in a veterinary teaching hospital environment

This study aimed to investigate sites for colonization and molecular epidemiology of antimicrobial-resistant Pseudomonas aeruginosa in a veterinary teaching hospital. Bacterial specimens from surface and liquid samples (n = 165) located in five rooms were collected three times every 2 months, and antimicrobial susceptibility was subsequently determined by minimum inhibitory concentrations. The genomes of resistant strains were further analyzed using whole-genome sequencing. Among 19 P. aeruginosa isolates (11.5%, 19/165), sinks were the most frequent colonization site (53.3%), followed by rubber tubes (44.4%), and anesthesia-breathing circuit (33.3%). The highest resistance to gentamicin (47.4%), followed by piperacillin/tazobactam (36.8%), levofloxacin (36.8%), and ciprofloxacin (36.8%), was observed from 19 P. aeruginosa isolates, of which 10 were resistant strains. Of these 10 antimicrobial-resistant isolates, five were multidrug-resistant isolates, including carbapenem. From the multilocus sequence typing (MLST) analysis, five sequence types (STs), including a high-risk clone of human ST235 (n = 3), and ST244 (n = 3), ST606 (n = 2), ST485 (n = 1), and ST3405 (n = 1) were identified in resistant strains. Multiresistant genes were identified consistent with STs, except ST235. The MLST approach and single nucleotide polymorphism analysis revealed a link between resistant strains from ward rooms and those from examination, wound care, and operating rooms. The improvement of routine cleaning, especially of sink environments, and the continued monitoring of antimicrobial resistance of P. aeruginosa in veterinary hospitals are necessary to prevent the spread of resistant clones and ensure infection control.

Emerging Concern with Imminent Therapeutic Strategies for Treating Resistance in Biofilm

Biofilm production by bacteria is presumed to be a survival strategy in natural environments. The production of biofilms is known to be influenced by a number of factors. This paper has precisely elaborated on the different factors that directly influence the formation of biofilm. Biofilm has serious consequences for human health, and a variety of infections linked to biofilm have emerged, rapidly increasing the statistics of antimicrobial resistance, which is a global threat. Additionally, to combat resistance in biofilm, various approaches have been developed. Surface modifications, physical removal, and the use of nanoparticles are the recent advances that have enabled drug discovery for treating various biofilm-associated infections. Progress in nanoparticle production has led to the development of a variety of biofilm-fighting strategies. We focus on the present and future therapeutic options that target the critical structural and functional characteristics of microbial biofilms, as well as drug tolerance mechanisms, such as the extracellular matrix, in this review.

The Yin and Yang of Skin Microbiota in "Swimmer Acne"

Cutibacterium acnes (C. acnes) is an organism implicated in the pathogenesis of acne. Despite regular immersion in antimicrobial chlorine, adolescent swimmers suffer from acne and tend to be resistant to standard therapies. Given the presence of Pseudomonas within swimming facilities, we hypothesized that "swimmer acne" is potentially driven by a different microbial mechanism. In this study, we aimed to examine the microbial dynamics of C. acnes and Pseudomonadaceae, a family of Gram-negative bacteria (includes Pseudomonas aeruginosa), in swimmers and its potential contribution to pathogenesis of acne in this population. Using fluorescence photography that measures the Coproporphyrin III (CPIII), we quantitated an absolute abundance of C. acnes present on the face of each participant pre- and post-swimming. In addition, 16S rRNA gene sequencing was utilized to assess relative abundance of the skin microbiota on each participant pre- and post-swimming. 16 swimmers (8 girls and 8 boys) completed the study. Seven had acne on the face. The CPIII fluorescence levels decreased for all swimmers after 1 hour of swimming (p-value <0.001). In contrast, relative abundance of C. acnes remained unchanged, while that of Pseudomonadaceae increased after swimming (p-value = 0.027). Comparing the relative abundances of Pseudomonadaceae before swimming, there was a significant increase in variance from the mean in acne group as compared to no acne group (p-value <0.001). Taken together, we conclude that the skin dysbiosis resulting from repeated decolonization and colonization of C. acnes and Pseudomonadaceae, respectively, can potentially be associated with the pathogenesis of acne in swimmers.

Pseudomonas aeruginosa Pneumonia: Evolution of Antimicrobial Resistance and Implications for Therapy

Pseudomonas aeruginosa (PA), a non-lactose-fermenting gram-negative bacillus, is a common cause of nosocomial infections in critically ill or debilitated patients, particularly ventilator-associated pneumonia (VAP), and infections of urinary tract, intra-abdominal, wounds, skin/soft tissue, and bloodstream. PA rarely affects healthy individuals, but may cause serious infections in patients with chronic structural lung disease, comorbidities, advanced age, impaired immune defenses, or with medical devices (e.g., urinary or intravascular catheters, foreign bodies). Treatment of pseudomonal infections is difficult, as PA is intrinsically resistant to multiple antimicrobials, and may acquire new resistance determinants even while on antimicrobial therapy. Mortality associated with pseudomonal VAP or bacteremias is high (> 35%) and optimal therapy is controversial. Over the past three decades, antimicrobial resistance (AMR) among PA has escalated globally, via dissemination of several international multidrug resistant "epidemic" clones. We discuss the importance of PA as a cause of pneumonia including health care-associated pneumonia, hospital-acquired pneumonia, VAP, the emergence of AMR to this pathogen, and approaches to therapy (both empirical and definitive).

Anti-Pseudomonas aeruginosa activity of a C16-terpene dilactone isolated from the endophytic fungus Neofusicoccum luteum of Kigelia africana (Lam.)

Fungal endophytes have the capacity to biosynthesize secondary metabolites that are produced by their host plants. In this study, a dilactone terpenoid of C₁₆ architecture was isolated from the fungal endophytes of Kigeliaafricana, in our attempt to identify anti-Pseudomonasaeruginosa metabolites. Thirty-eight fungal isolates were cultured for biomolecule production over a period of thirty days. Extracts from three (ZF 34, ZF 52 and ZF 91) of the fungi showed good anti-P.aeruginosa activity, with ZF 52 presenting the best MIC of 19.53 µg/mL and was accordingly subjected to chromatographic separation. Based on nuclear magnetic resonance (NMR) spectroscopy, high resolution mass spectrometry and single crystal X-ray diffraction (XRD) analyses, the isolated compound was identified as a C₁₆-terpene dilactone, with a structure consistent with that of the known diterpene, CJ-14445. The isolated dilactone showed anti-P.aeruginosa activity with MIC of 0.61 µg/mL, signifying the antibacterial potential of the biomolecule. The bioactive fungal isolate (ZF 52) was identified as Neofusicoccumluteum based on genomic DNA sequencing. This is the first report of the endophyte N.luteum from K.africana and the first reported occurrence of CJ-14445 in the fungus.

Risks of antibiotic resistance genes and antimicrobial resistance under chlorination disinfection with public health concerns

As a widely used disinfection technology, the effects of chlorination on antibiotic resistome and bacterial community received great scientific concerns, while the pathogens associated health risks kept largely unknown. With this concern, the present study used metagenomic analysis combined with culture method to reveal chlorination effects on antibiotic resistance genes (ARGs) and their bacterial hosts (total microbes and Escherichia coli) through simulating the chlorination dosage with human health concerns (drinking water and swimming pool). The resistome profiling showed that chlorination process could significantly decrease both abundance and diversity of total ARGs, while with limited removal rates of 6.0-8.7% for opportunistic pathogens E. coli isolates. Of all the observed 515 ARG subtypes, 105 core subtypes were identified and persistent during chlorination for both total microbes and E. coli. Antibiotic susceptibility test showed that chlorination treatment could efficiently remove multi-resistant E. coli isolates but select for tetracycline resistant isolates. Five ARG-carrying genomes (assigned to Bacteroidetes, Firmicutes, Actinobacteria) enriched by 18.1-102% after chlorination were retrieved by using metagenomic binning strategies. Bray-Curtis dissimilarity, network and procrustes analyses all indicated the remained antibiotic resistome and bacterial community were mainly chlorination-driven. Furthermore, a systematic pipeline for monitoring chlorination-associated antimicrobial resistance risks was proposed. These together enhance our knowledge of chlorination treatment associated public concerns, as important reference and guidance for surveillance and control of antibiotic resistance.

Occurrence of P. aeruginosa in Water Intended for Human Consumption and in Swimming Pool Water

Considering the fact that water is a basic need of every living being, it is important to ensure its safety. In this work, the data on the presence of the opportunistic pathogen P. aeruginosa in drinking water (n = 4171) as well as in pool water (n = 5059) in Primorje-Gorski Kotar County in Croatia in the five-year period (2016–2020) were analysed. In addition, the national criteria were compared with those of neighboring countries and worldwide. The proportion of P. aeruginosa-positive samples was similar for drinking water (3.9%) and pool water (4.6%). The prevalence of this bacterium was most pronounced in the warmer season. P. aeruginosa-positive drinking water samples were mostly collected during building commissioning, while pool samples were from entertainment and spa/hydromassage pools. Outdoor pools showed a higher percentage of positive samples than indoor pools, as well as the pools filled with freshwater rather than seawater. The highest P. aeruginosa load was found in rehabilitation pools. Croatia, Serbia and Montenegro are countries that have included P. aeruginosa in their national regulations as an indicator of the safety of water for human consumption as well as for bottled water, while Slovenia and Bosnia and Herzegovina have limited this requirement to bottled water only. In the case of swimming pool water, this parameter is mandatory in all countries considered in this study.

COVID-19: Research Directions for Non-Clinical Aerosol-Generating Facilities in the Built Environment

Physical contact and respiratory droplet transmission have been widely regarded as the main routes of COVID-19 infection. However, mounting evidence has unveiled the risk of aerosol transmission of the virus. Whereas caution has been taken to avoid this risk in association with clinical facilities, facilities such as spa pools and Jacuzzis, which are characterized by bubble-aerosol generation, high bather loads, and limited turnover rates, may promote aerosol transmission. Focusing on these non-clinical facilities in the built environment, a review study was undertaken. First, the typical water disinfection and ventilation-aided operations for the facilities were illustrated. Second, cross comparisons were made between the applicable standards and guidelines of the World Health Organization and countries including Australia, Canada, China, the United Kingdom, and the United States. The similarities and differences in their water quality specifications, ventilation requirements, and air quality enhancement measures were identified; there were no specific regulations for preventing aerosol transmission at those aerosol-generating facilities. Third, a qualitative review of research publications revealed the emergence of studies on potential air-borne transmission of COVID-19, but research on built facilities posing high risks of aerosol transmission remains scant. This study’s results inform key directions for future research on abating aerosol transmission of COVID-19: the development of bespoke personal protective equipment and engineering and management controls on water quality, ventilation, and air quality.

Assessment of hygienic conditions of recreational facility restrooms: an integrated approach

Introduction

Microbiological quality of recreational environments included restrooms, is generally assessed by water and surface monitoring. In this study, an environmental monitoring, conducted in spring, of swimming pool restrooms of a recreation center located in the Marche region has been carried out. Seven water samples and seven surface swabs were collected. Moreover, six air samples have been included. The aim of this study was to evaluate if air microbiological monitoring, along with molecular detection in real-time PCR, could give additional useful information about the hygienic conditions of the facility.

Methods

Heterotrophic Plate Count (HPC) both at 22°C (psychrophilic) and 37°C (mesophilic) was determined by separate cultures in all samples. The presence of Legionella pneumophila and Pseudomonas aeruginosa was evaluated by both culture and real-time PCR.

Results

The analysis of shower water recorded a HPC load of mesophilic bacteria (37°C) more than 10-fold higher in men restroom, respect to women’s one (> 100 vs < 10 CFU/ml), while in air samples was between < 100 and > 500. Concerning pathogen presence, both species Legionella pneumophila and Pseudomonas aeruginosa were detected only in men restroom, but in different sample types by using different methods (culture and real-time PCR).

Conclusions

Air sampling may offer the advantage of giving more representative data about microbial presence in restrooms, including bacterial species transmitted through aerosol, like Legionella. Moreover, the concurrent use of molecular and microbiological detection in an integrated approach could offer the advantage of greater sensitivity.

Proteomic profiling of clinical and environmental strains of Pseudomonas aeruginosa

Pseudomonas aeruginosa is a ubiquitous bacterium, which is able to change its physiological characteristics in response to different habitats. Environmental strains are presumably less pathogenic than clinical strains and whether or not the clinical strains originate from the environment or through inter-host transmission remains poorly understood. To minimize the risk of infection, a better understanding of proteomic profiling of P. aeruginosa is necessary for elucidating the correlation between environmental and clinical strains. Based on antimicrobial susceptibility and patterns of virulence, we selected 12 clinical and environmental strains: (i) environmental, (ii) multidrug resistant (MDR) clinical and (iii) susceptible clinical strains. Whole-cell protein was extracted from each strain and subjected to two-dimensional differential gel electrophoresis (2-D DIGE) and liquid chromatography tandem mass spectrometry quadrupole time-of-flight (LC-MS QTOF). All 12 strains were clustered into 3 distinct groups based on their variance in protein expression. A total of 526 matched spots were detected and four differentially expressed protein spots (p < 0.05) were identified and all differential spots were downregulated in MDR strain J3. Upregulation of chitin binding and BON domain proteins was present in the environmental and some MDR strains, whereas the clinical strains exhibited distinct proteomic profiles with increased expression of serine protein kinase and arginine/ornithine transport ATP-binding proteins. Significant difference in expression was observed between susceptible clinical and MDR strains, as well as susceptible clinical and environmental strains. Transition from an environmental saprophyte to a clinical strain could alter its physiological characteristics to further increase its adaptation.

[An Itching Pleasure]

An Itching Pleasure Abstract. A 50-year-old female patient presents in the emergency department with an itchy, acneiform exanthema on the trunk and malaise for two days. Laboratory testing showed no abnormalities. After further questioning, the patient reported frequent use of her new whirlpool. Based on the medical history and the clinic we suspected a pseudomonas folliculitis. A bacterial culture of the pustules showed growth of Pseudomonas aeruginosa, which confirmed the diagnosis. Systemic antibiotics were not necessary in the absence of risk factors for severe progress or immunosuppression. The exanthema healed within a few days without any complications by using external disinfectants.

Environmental risks of Pseudomonas aeruginosa-What to advise patients and parents

Pseudomonas aeruginosa (PsA) is commonly found in soil and water so is impossible to avoid completely. Parents/carers of children with cystic fibrosis (CF) are concerned about them acquiring PsA from the environment, and different families view risk differently. Our ethos is to enable children with CF to take part as much as possible in educational and fun home activities, in order to maintain their quality of life (and their family's), and not have them feel different from other children. This review presents advice for families as to what they must definitely avoid, what they must take precautions with but can allow, and what they must not avoid. It is mostly evidence-based, but where evidence is lacking it a consensus view from the Paediatric CF Unit at the Royal Brompton Hospital.

Updated research agenda for water, sanitation and antimicrobial resistance

The emergence and spread of antimicrobial resistance (AMR), including clinically relevant antimicrobial-resistant bacteria, genetic resistance elements, and antibiotic residues, presents a significant threat to human health. Reducing the incidence of infection by improving water, sanitation, and hygiene (WASH) is one of five objectives in the World Health Organization's (WHO) Global Action Plan on AMR. In September 2019, WHO and the Health-Related Water Microbiology specialist group (HRWM-SG) of the International Water Association (IWA) organized its third workshop on AMR, focusing on the following three main issues: environmental pathways of AMR transmission, environmental surveillance, and removal from human waste. The workshop concluded that despite an increase in scientific evidence that the environment may play a significant role, especially in low-resource settings, the exact relative role of the environment is still unclear. Given many antibiotic-resistant bacteria (ARB) can be part of the normal gut flora, it can be assumed that for environmental transmission, the burden of fecal-oral transmission of AMR in a geographical area follows that of WASH-related infections. There are some uncertainties as to the potential for the propagation of particular resistance genes within wastewater treatment plants (WWTPs), but there is no doubt that the reduction in viable microbes (with or without resistance genes) available for transmission via the environment is one of the goals of human waste management. Although progress has been made in the past years with respect to quantifying environmental AMR transmission potential, still more data on the spread of environmental AMR within human communities is needed. Even though evidence on AMR in WWTPs has increased, the reduction in the emergence and spread of AMR by basic sanitation methods is yet unresolved. In order to contribute to the generation of harmonized One Health surveillance data, WHO has initiated an integrated One Health surveillance strategy that includes the environment. The main challenge lies in rolling it out globally including to the poorest regions.

Hot Tub-Associated Pseudomonas Folliculitis: A Case Report and Review of Host Risk Factors

Pseudomonas aeruginosa folliculitis is an infection of the skin commonly associated with swimming pool and hot tub use. It often presents as outbreaks affecting multiple individuals using the same contaminated public water facility. We present a case report of a 50-year-old woman who developed pseudomonal folliculitis after using a hot tub with multiple family members. No other family member developed folliculitis. Factors contributing to susceptibility to P. aeruginosa infection are reviewed.

Comparative study on the microbial quality in the swimming pools disinfected by the ozone-chlorine and chlorine processes in Tabriz, Iran

Applying a desirable disinfestation process is necessary to control the pathogenic microorganisms in the swimming pools and prevent both dermal and intestinal effects. Therefore, the present study was conducted to compare the bacterial community and diversity in the two swimming pools disinfected by the chlorine and ozone (O₃)-chlorine processes. A total of 24 samples were taken from the two swimming pools in three distinct seasons to analyze the bacterial and physico-chemical indicators. Culture and molecular methods were used to evaluate the microbial quality. Two sets of sample taken from the pools with the maximum swimmer load in the summer were investigated by the next-generation sequencing (NGS) technique. In total, 410 and 406 bacterial species were identified in the chlorine- and ozone-chlorine-disinfected pools, respectively. Among the eight dominant bacterial species in each swimming pool, Pseudomonas alcaliphila, Pseudomonas stutzeri, and Pseudomonas acnes were common species between the two studied pools. Oleomonas sagaranensis (350 reads/18593), Staphylococcus caprae (302 reads /18593), and Anaerococcus octavius (110 reads/18593) were among the dominant bacteria in the chlorine-disinfected pool. Bacterial diversity was lower in the ozone-chlorine-disinfected pool than the other one, and the highest bacterial sequencing belonged to the genus Pseudomonas (85.79%). Results showed that water quality of in O₃-chlorine-disinfected pool was more desirable than the chlorine-disinfected pool. Molecular methods along with conventional culture methods would be advantageous for microbial assessment in the swimming pools.

2018 AAHA Infection Control, Prevention, and Biosecurity Guidelines*

A veterinary team’s best work can be undone by a breach in infection control, prevention, and biosecurity (ICPB). Such a breach, in the practice or home-care setting, can lead to medical, social, and financial impacts on patients, clients, and staff, as well as damage the reputation of the hospital. To mitigate these negative outcomes, the AAHA ICPB Guidelines Task Force believes that hospital teams should improve upon their current efforts by limiting pathogen exposure from entering or being transmitted throughout the hospital population and using surveillance methods to detect any new entry of a pathogen into the practice. To support these recommendations, these practice-oriented guidelines include step-by-step instructions to upgrade ICPB efforts in any hospital, including recommendations on the following: establishing an infection control practitioner to coordinate and implement the ICPB program; developing evidence-based standard operating procedures related to tasks performed frequently by the veterinary team (hand hygiene, cleaning and disinfection, phone triage, etc.); assessing the facility’s ICPB strengths and areas of improvement; creating a staff education and training plan; cataloging client education material specific for use in the practice; implementing a surveillance program; and maintaining a compliance evaluation program. Practices with few or no ICPB protocols should be encouraged to take small steps. Creating visible evidence that these protocols are consistently implemented within the hospital will invariably strengthen the loyalties of clients to the hospital as well as deepen the pride the staff have in their roles, both of which are the basis of successful veterinary practice.

Prevalence and antibiotic resistance of Pseudomonas aeruginosa in water samples in central Italy and molecular characterization of oprD in imipenem resistant isolates

Scope

This study aimed to analyse the prevalence, antibiotic resistance and genetic relatedness of P. aeruginosa isolates obtained from potable and recreational water samples (n. 8,351) collected from different settings (swimming pools, n. 207; healthcare facilities, n 1,684; accommodation facilities, n. 1,518; municipal waterworks, n. 4,500; residential buildings, n. 235). Possible mechanisms underlying resistance to imipenem, with particular focus on those involving oprD-based uptake, were also explored.

Methods and results

Isolation and identification of Pseudomonas aeruginosa was performed according to the standardized procedure UNI EN ISO 16266:2008 followed by PCR confirmation. Antibiotic Susceptibility testing was conducted according to EUCAST standardized disk diffusion method. Genetic relatedness of strains was carried out by RAPD. The sequence of the oprD gene was analyzed by standard method. Fifty-three samples (0.63%) were positive for P. aeruginosa, of which 10/207 (4.83%) were from swimming pools. Five isolates (9.43%) were resistant to imipenem, one to Ticarcillin + Clavulanate, one to both Piperacillin and Ticarcillin + Clavulanate. The highest isolation rate of imipenem resistant P. aeruginosa was observed in swimming pool water. Identical RAPD profiles were found in isolates from the same location in the same year or even in different years.

Conclusions

Imipenem resistant strains were identified as carbapenemase-negative and resistance has been associated with inactivating mutations within the oprD gene, with a concomitant loss of porin. RAPD results proved that a water system can remain colonized by one strain for long periods and the contamination may be difficult to eradicate.

This study has revealed the presence of P. aeruginosa in different water samples, including resistant strains, especially in swimming pools, and confirmed the role of porins as a contributing factor in carbapenem resistance in Gram-negative bacteria.

Low overlap between carbapenem resistant Pseudomonas aeruginosa genotypes isolated from hospitalized patients and wastewater treatment plants

The variability of carbapenem-resistant Pseudomonas aeruginosa strains (CRPA) isolated from urine and respiratory samples in a large microbiological laboratory, serving several health care settings, and from effluents of two wastewater treatment plants (WWTP) from the same region was assessed by PFGE typing and by resistance to 10 antibiotics. During the 12-month period altogether 213 carbapenem-resistant P. aeruginosa isolates were cultured and distributed into 65 pulsotypes and ten resistance profiles. For representatives of all 65 pulsotypes 49 different MLSTs were determined. Variability of clinical and environmental strains was comparable, 130 carbapenem-resistant P. aeruginosa obtained from 109 patients were distributed into 38 pulsotypes, while 83 isolates from WWTPs were classified into 31 pulsotypes. Only 9 pulsotypes were shared between two or more settings (hospital or WWTP). Ten MLST were determined for those prevalent pulsotypes, two of them (ST111 and ST235) are among most successful CRPA types worldwide. Clinical and environmental carbapenem-resistant P. aeruginosa strains differed in antibiotic resistance. The highest proportion of clinical isolates was resistant to piperacillin/tazobactam (52.3%) and ceftazidime (42.3%). The highest proportion of environmental isolates was resistant to ceftazidime (37.1%) and ciprofloxacin (35.5%). The majority of isolates was resistant only to imipenem and/or meropenem. Strains with additional resistances were distributed into nine different patterns. All of them included clinically relevant strains, while environmental strains showed only four additional different patterns.

Isolation and characterization of a bacteriophage and its utilization against multi-drug resistant Pseudomonas aeruginosa-2995

AIMS

To identify, isolate, and characterize a lytic bacteriophage against the multiple-drug resistant clinical strain of Pseudomonas aeruginosa-2995 and to determine the phage efficacy against the bacterial planktonic cells and the biofilm.

MAIN METHODS

Wastewater was used to isolate a bacteriophage. The phage was characterized with Transmission electron microscopy (TEM). Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS PAGE) was used to identify the expressed proteins. Bacteria were cultured in both suspension and biofilm to check and compare their susceptibility to phage lytic action. The activity of the phage (determined as AZ1) was determined against P. aeruginosa-2995 in both planktonic cells and the biofilm.

KEY FINDINGS

A bacteriophage, designated as AZ1, was isolated from waste water showing a narrow host range. AZ1 was characterized by TEM and could be identified as an isolate in the family Siphoviridae [order Caudovirals]. Seventeen structural proteins ranging from about 12 to 110kDa were found through SDS-PAGE analysis. Its genome was confirmed as dsDNA with a length of approx. 50kb. The log-phase growth of P. aeruginosa-2995 was significantly reduced after treatment with AZ1 (4.50×10⁸ to 2.1×10³CFU/ml) as compared to control. Furthermore, phage AZ1 significantly reduced 48h old biofilm biomass about 3-fold as compared to control.

SIGNIFICANCE

Pseudomonas aeruginosa is a ubiquitous free-living opportunistic human pathogen characterized by high antibiotic tolerance and tendency for biofilm formation. The phage, identified in this study, AZ1, showed promising activity in the destruction of both planktonic cells and biofilm of P. aeruginosa-2995. However, complete eradication may require a combination of phages.

Otitis externa in military divers: more frequent and less harmful than reported

INTRODUCTION

Although otitis externa (OE) is a common disease, data related to (military) divers are limited. This study aimed to determine the incidence of OE in military divers during their initial training. We also wished to consider seasonal influences on incidence and whether early detection increases completion of the diving course.

METHODS

From January 2011 to October 2016 the Royal Netherlands Navy Diving School trained 189 divers. Up to December 2015 we used the training records for the analyses. From January 2016 onward all divers were prospectively screened. Pearson's chi-squared 2 and Fisher's exact tests were used to analyse the data.

RESULTS

In the 162 included divers, 30 cases of OE were identified. The incidence in 2016 was significantly higher than in 2011-2015 (17/35 (49%) versus 13/127 (10%), P < 0.001). Almost all cases developed after three weeks of diving. No influence of season was found (P = 0.354). Early diagnosis and treatment of OE does not seem to affect completion of diving courses (P = 0.28). Only in three cases did a diver have to discontinue the course due to OE.

DISCUSSION

This study suggests that OE is more frequent among military divers than earlier reported, most likely caused by prolonged water exposure. Diving activities can often be continued with standard topical treatment.

[Cutaneous lesions during hot-tub hypersensitivity pneumonitis: Pseudomonas folliculitis ?]

BACKGROUND

Interstitial lung disease, cutaneous rash and elevated serum angiotensin converting enzyme (ACE) may suggest diagnoses other than sarcoidosis.

PATIENTS AND METHODS

A 58-year-old man had presented dyspnoea for 2 years with increased angiotensin-converting enzyme, as well as an interstitial syndrome and micronodules. The possibility of sarcoidosis was raised. Systemic corticosteroids resulted in improvement of the dyspnoea although it recurred on dose reduction. We noted fluctuating eczematous macules of the limbs with a histology of aspecific folliculitis. The identification of Mycobacterium avium complex (MAC) in the bronchoalveolar wash prompted us to initiate antimycobacterial therapy, but this was to no avail. Review of the CT-scan and questioning of the patient (daily use of a Jacuzzi for 7 years) resulted in diagnosis of hypersensitivity pneumonitis due to MAC. The cutaneous lesions were taken to indicate "hot tub folliculitis". Discontinuation of hot-tub use and a short course of oral corticosteroids resulted in healing within 4 months, with no recurrence at 2 years.

DISCUSSION

HTL is a form of hypersensitivity pneumonitis due to the presence of MAC in the water of Jacuzzis. This condition regresses spontaneously without treatment on discontinuation of Jacuzzi use. Hot-tub folliculitis due to Pseudomonas aeruginosa (PA) presents as macules and papules on covered skin areas (swimsuit) within 48hours of bathing and often declines within 2 weeks.

CONCLUSION

Our case is original as regards the concomitant lung and cutaneous involvement associated with Jacuzzi use, with an immunoallergic mechanism for the MAC and probably an infectious mechanism for the PA.

Hypersensitivity pneumonitis in a beautician

A 52-year-old non-smoking beautician using a skincare device spraying steam and ozone (a "vapozone" facial steamer) was referred for progressive dyspnea and dry cough during working periods. Although spirometry was normal, she had decreased diffusing capacity of the lung for carbon monoxide, bronchiolitis with air trapping on high-resolution CT scan and 60% lymphocytosis by bronchoalveolar lavage. Twenty-six antigens were tested and serum-specific precipitins were found mainly against Pseudomonas sp. and Mycobacterium mucogenicum. Cultures from her skincare device isolated Pseudomonas sp. Outcome was favorable with cessation of occupational exposure to the device, without any medication. This is the first report of a case of HP in a beautician due to steam contaminated by Pseudomonas sp. from a vapozone. HP, and not only asthma and contact dermatitis, should be suspected in beauticians with respiratory symptoms. Am. J. Ind. Med. 59:1041-1045, 2016. © 2016 Wiley Periodicals, Inc.

Antibiotic and metal resistance in a ST395 Pseudomonas aeruginosa environmental isolate: A genomics approach

We analyzed the resistome of Pseudomonas aeruginosa E67, an epiphytic isolate from a metal-contaminated estuary. The aim was to identify genetic determinants of resistance to antibiotics and metals, assessing possible co-selection mechanisms. Identification was based on phylogenetic analysis and average nucleotide identity value calculation. MLST affiliated E67 to ST395, previously described as a high-risk clone. Genome analysis allowed identifying genes probably involved in resistance to antibiotics (e.g. beta-lactams, aminoglycosides and chloramphenicol) and metals (e.g. mercury and copper), consistent with resistance phenotypes. Several genes associated with efflux systems, as well as genetic determinants contributing to gene motility, were identified. Pseudomonas aeruginosa E67 possesses an arsenal of resistance determinants, probably contributing to adaptation to a polluted ecosystem. Association to mobile structures highlights the role of these platforms in multi-drug resistance. Physical links between metal and antibiotic resistance genes were not identified, suggesting a predominance of cross-resistance associated with multidrug efflux pumps.

The characteristics of genetically related Pseudomonas aeruginosa from diverse sources and their interaction with human cell lines

We investigated a collection of Pseudomonas aeruginosa strains from hospitalised patients (n = 20) and various environmental sources (n = 214) for their genetic relatedness; virulence properties; antibiotic resistance; and interaction with intestinal (Caco-2), renal (A-498), and lung (Calu-3) cell lines. Using RAPD–PCR, we found high diversity among the strains irrespective of their sources, with only 6 common (C) types containing strains from both a clinical and environmental source. Environmental strains belonging to these C-types showed greater adhesion to A-498 cells than did clinical strains (17 ± 13 bacteria/cell versus 13 ± 11 bacteria/cell; p < 0.001), whereas clinical strains showed significantly greater adhesion to Calu-3 and Caco-2 cells than did environmental strains (p < 0.001 for both). The virulence genes and antibiotic resistance profiles of the strains were similar; however, the prevalence of environmental strains carrying both exoS and exoU was significantly (p < 0.0368) higher than clinical strains. While all strains were resistant to ticarcillin and ticarcillin–clavulanic acid, resistance against aztreonam, gentamicin, amikacin, piperacillin, and ceftazidime varied among environmental and clinical strains. These results suggest that environmental strains of P. aeruginosa carry virulence properties similar to clinical strains, including adhesion to various human cell lines, with some strains showing a higher adhesion to specific cell lines, indicating they may have a better ability to cause infection in those sites under predisposing conditions of the host.

Evaluation of the Pseudalert/Quanti-Tray MPN Test for the Rapid Enumeration of Pseudomonas aeruginosa in Swimming Pool and Spa Pool Waters

This study assessed the performance of a new most probable number test (Pseudalert/Quanti-Tray) for the enumeration of Pseudomonas aeruginosa from swimming pool and spa pool waters by comparing it to the international and national membrane filtration-based culture methods for P. aeruginosa: ISO 16266:2006 and UK The Microbiology of Drinking Water-Part 8 (MoDW Part 8) which both use Pseudomonas CN agar. The comparison was based on the calculation of mean relative differences between the two methods conducted according to ISO 17994:2014. Using both routine pool water samples (149 from 8 laboratories) and artificially contaminated samples (309 from 7 laboratories), paired counts from each sample and enumeration method were analysed. For routine samples, there were insufficient data for a conclusive assessment, but the data do indicate at least equivalent performance of Pseudalert/Quanti-Tray to the reference methods. For the artificially contaminated samples, the data also did not result in a statistically conclusive assessment but did indicate potentially better performance of Pseudalert/Quanti-Tray. Combining the data from the routine samples and artificially contaminated samples resulted in an ISO 17994 outcome that the two methods were not statistically significantly different. Thus, the Pseudalert/Quanti-Tray method is an acceptable alternative to ISO 16266 and MoDW Part 8. The Pseudalert/Quanti-Tray method has the advantage in that it does not require confirmation testing, and of providing confirmed counts within 24-28 h incubation compared to 40-48 h or longer for the ISO 16266 and MoDW Part 8 methods.

identification of Pseudomonas spp. as amoeba-resistant microorganisms in isolates of Acanthamoeba

Acanthamoeba is a “Trojan horse” of the microbial world. The aim of this study was to identify the presence of Pseudomonas as an amoeba-resistant microorganism in 12 isolates of Acanthamoeba. All isolates showed the genus Pseudomonas spp. as amoeba-resistant microorganisms. Thus, one can see that the Acanthamoeba isolates studied are hosts of Pseudomonas.

Dermatological conditions of aquatic athletes

Numerous manuscripts have described dermatologic conditions commonly seen in swimmers. This review provides an update on water dermatoses and discusses newly described conditions such as allergic contact dermatitis to chemical ingredients like potassium peroxymonosulate in pool water. In order to organize water related skin conditions, we have divided the skin conditions into a number of categories. The categories described include infectious and organism-related dermatoses, irritant and allergic dermatoses, and sun-induced dermatoses. The vast majority of skin conditions involving the water athlete result from chemicals and bacteria in the differing aquatic environments. When considering the effects of swimming on the skin, it is also useful to differentiate between exposure to freshwater (lakes, ponds and swimming pools) and exposure to saltwater. The risk of melanoma amongst swimmers is increased, and the use of SPF 30 or greater sunscreen and protective clothing is highly recommended. Swimmers should be reminded to generously apply sunscreen and be instructed on proper sunscreen usage. This review will serve as a guide for dermatologists, athletes, coaches, and other medical professionals in recognition and treatment of these conditions. We also intend for this review to provide dermatologist with a basic framework for the diagnosis and treatment of a few rarely described dermatological conditions in swimmers.

Aerosolization of respirable droplets from a domestic spa pool and the use of MS-2 coliphage and Pseudomonas aeruginosa as markers for Legionella pneumophila

Legionnaires' disease can result when droplets or aerosols containing legionella bacteria are inhaled and deposited in the lungs. A number of outbreaks have been associated with the use of a spa pool where aeration, a high water temperature, and a large and variable organic load make disinfectant levels difficult to maintain. Spa pool ownership is increasing, and the aim of this study, using two surrogate organisms (MS-2 coliphage and Pseudomonas aeruginosa [a natural contaminant]), was to assess the potential risk to domestic users when disinfection fails. A representative "entry level" domestic spa pool was installed in an outdoor courtyard. The manufacturer's instructions for spa pool maintenance were not followed. A cyclone sampler was used to sample the aerosols released from the spa pool with and without activation of the air injection system. Samples were taken at increasing heights and distances from the pool. An aerodynamic particle sizer was used to measure the water droplet size distribution at each sample point. When the air injection system was inactivated, neither surrogate organism was recovered from the air. On activation of the air injection system, the mean mass of droplets within the respirable range (10 cm above the water line) was 36.8 μg cm(-3). This corresponded to a mean air concentration of P. aeruginosa of 350 CFU m(-3). From extrapolation from animal data, the estimated risk of infection from aerosols contaminated with similar concentrations of Legionella pneumophila was 0.76 (males) and 0.65 (females). At 1 m above and/or beyond the pool, the mean aerosol mass decreased to 0.04 μg cm(-3) and corresponded to a 100-fold reduction in mean microbial air concentration. The estimated risk of infection at this distance was negligible.

Cultivable bacterial microbiota of northern bobwhite (Colinus virginianus): a new reservoir of antimicrobial resistance?

The northern bobwhite (Colinus virginianus) is an ecologically and economically important avian species. At the present time, little is known about the microbial communities associated with these birds. As the first step to create a quail microbiology knowledge base, the current study conducted an inventory of cultivable quail tracheal, crop, cecal, and cloacal microbiota and associated antimicrobial resistance using a combined bacteriology and DNA sequencing approach. A total of 414 morphologically unique bacterial colonies were selected from nonselective aerobic and anaerobic cultures, as well as selective and enrichment cultures. Analysis of the first 500-bp 16S rRNA gene sequences in conjunction with biochemical identifications revealed 190 non-redundant species-level taxonomic units, representing 160 known bacterial species and 30 novel species. The bacterial species were classified into 4 phyla, 14 orders, 37 families, and 59 or more genera. Firmicutes was the most commonly encountered phylum (57%) followed by Actinobacteria (24%), Proteobacteria (17%) and Bacteroidetes (0.02%). Extensive diversity in the species composition of quail microbiota was observed among individual birds and anatomical locations. Quail microbiota harbored several opportunistic pathogens, such as E. coli and Ps. aeruginosa, as well as human commensal organisms, including Neisseria species. Phenotypic characterization of selected bacterial species demonstrated a high prevalence of resistance to the following classes of antimicrobials: phenicol, macrolide, lincosamide, quinolone, and sulphate. Data from the current investigation warrant further investigation on the source, transmission, pathology, and control of antimicrobial resistance in wild quail populations.

Activities of selected medicinal plants against multi-drug resistant Gram-negative bacteria in Cameroon

BACKGROUND

Medicinal plants are used worldwide for several human ailments including bacterial infections. The present work was designed to assess the in vitro antibacterial activities of some Cameroonian medicinal plants including Entada abyssinica, Entada africana, Pentaclethra macrophylla, Allexis cauliflora, Anthocleista leibrechtsiana, Carapa procera, Carica papaya and Persea americana against Gram-negative bacteria expressing multidrug resistant (MDR) phenotypes.

METHODS

The microbroth dilution was used to determine the minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC) of the samples against eight bacterial strains belonging to four species, Escherichia coli, Enterobacter aerogenes, Klebsiella pneumoniae and Providencia stuartii.

RESULTS

The extracts displayed selective antibacterial activities with the minimal inhibitory concentrations (MIC) values ranges of 64 to 1024 µg/mL. The most active extract was that from Pentaclethra macrophylla (TPM) that showed inhibitory activities against five of the eight (62.5%) tested bacteria. The lowest MIC value (64 µg/mL) was recorded with the crude extract of Entada africana against E. coli AG100A whilst the best MBC (256 µg/mL) value was also obtained with methanol extract of Persea americana against this bacterial strain.

CONCLUSION

The results of the present work provide baseline information on the possible use of Pentaclethra macrophylla, Entada africana and Entada abyssinica in the treatment of selected bacterial infections.

Going with the flow or swimming against the tide: should children with central venous catheters swim?

Children who require long-term parenteral nutrition (PN) have central venous catheters (CVCs) in place to allow the safe and effective infusion of life-sustaining fluids and nutrition. Many consider recreational swimming to be a common part of childhood, but for some, the risk may outweigh the benefit. Children with CVCs may be at increased risk of exit site, tunnel, and catheter-related bloodstream infections (CRBSIs) if these catheters are immersed in water. The purpose of this review is to evaluate the current literature regarding the risk of infection for patients with CVCs who swim and determine if there is consensus among home PN (HPN) programs on this controversial issue. A total 45 articles were reviewed and 16 pediatric HPN programs were surveyed regarding swimming and CVCs. Due to the limited data available, a firm recommendation cannot be made. Recreational water associated outbreaks are well documented in the general public, as is the presence of human pathogens even in chlorinated swimming pools. As a medical team, practitioners can provide information and education regarding the potential risk, but ultimately the decision lies with the parents. If the parents decide swimming is worth the risk, they are encouraged to use products designed for this use and to change their child's dressing immediately after swimming. Due to our experience with a fatal event immediately after swimming, we continue to strongly discourage patients with CVCs from swimming. Further large and well-designed studies regarding the risk of swimming with a CVC are needed to make a strong, evidence-based recommendation.

A new pentaplex-nested PCR to detect five pathogenic bacteria in free living amoebae

Changes in water use and anthropogenic activity have major impacts on the quality of natural aquatic ecosystems, water distribution and wastewater plants. One of the main problems is the presence of some pathogenic microorganisms that are resistant to disinfection procedures when they are hosted by free living amoeba and that in many cases are hardly detectable by culture-based procedures. In this work we report a sensitive, low-cost procedure consisting of a pentaplex-nested PCR that allows simultaneous detection of Legionella pneumophila, Mycobacterium spp., Pseudomonas spp., Vibrio cholerae and the microcystin-producing cyanobacteria Microcystis aeruginosa. The method has been used to detect the presence of these pathogenic bacteria in water and inside free living amoeba. Its validation in 72 samples obtained from different water sources from Aragon (Spain) evidences that Mycobacterium and Pseudomonas spp are prevailing as amoeba-resistant bacteria.

Antibiotic overuse and resistance in dermatology

Antibiotics have a significant role in dermatology, treating a wide range of diseases, including acne, rosacea, inflammatory skin conditions and skin structure infections, such as cellulitis, folliculitis, carbuncles, and furuncles. Because of their consistent use, utility, and availability, antibiotics are susceptible to overuse within the medical practice, and, specific to this discussion, in the dermatologic setting. The issue of continuously increasing risk of antibiotic resistance remains an important concern to the dermatologist. The scope of this review will be to provide an overview of the common antibiotics used in the dermatologic setting with an emphasis on identifying areas of overuse, reported bacterial resistance, and discussion of clinical management aimed at decreasing antibiotic resistance.

Commensal Pseudomonas species isolated from wastewater and freshwater milieus in the Eastern Cape Province, South Africa, as reservoir of antibiotic resistant determinants

Pseudomonas species are opportunistic pathogens with implications in a wide range of diseases including cystic fibrosis and sickle cell anaemia. Because of their status as multidrug resistant (MDR) and extremely drug resistant (XDR) bacteria Pseudomonas species represent a threat to public health. Prevalence, antibiogram and associated antibiotic resistant genes of Pseudomonas species isolated from freshwater and mixed liquor environments in the Eastern Cape Province of South Africa were assessed. Polymerase chain reaction (PCR) based technique was used to identify the isolates and screen for antibiotic resistant genes. The result shows occurrence of Pseudomonas spp. in freshwater and mixed liquor as follows: 71.42% and 37.5% (P. putida), 14.28% and 31.25% (P. flourescens), 7.14% and 6.25% (P. aeruginosa) and 7.14% and 25% for other Pseudomonas species respectively. Disk diffusion antibiogram of the Pseudomonas isolates from the two locations showed 100% resistance to penicillin, oxacillin, clindamycin, rifampicin and 100% susceptibility to ciprofloxacin and gentamicin with varied percentage resistances to cephalothin, nalidixic acid, tetracycline, and ampicillin. The bla_TEM antibiotic resistant gene was detected in 12.5% of P. putida, 57.14% of P. fluorescens, 100% P. aeruginosa and 40% in other Pseudomonas species. Similarly, Integrons conserved segment were detected in 12.5% of P. putida, 57.14% of P. fluorescens, 100% of P. aeruginosa and 40% of other Pseudomonas species. The presence of bla_TEM gene and integrons conserved segment in some of the isolates is worrisome and suggest Pseudomonas species as important reservoirs of multidrug resistance genes in the Eastern Cape Province environment.

Antibacterial activities of selected Cameroonian spices and their synergistic effects with antibiotics against multidrug-resistant phenotypes

Background

The emergence of multi-drug resistant (MDR) phenotypes is a major public health problem today in the treatment of bacterial infections. The present study was designed to evaluate the antibacterial activities of the methanol extracts of eleven Cameroonian spices on a panel of twenty nine Gram negative bacteria including MDR strains.

Methods

The phytochemical analysis of the extracts was carried out by standard tests meanwhile the liquid micro-broth dilution was used for all antimicrobial assays.

Results

Phytochemical analysis showed the presence of alkaloids, phenols and tannins in all plants extracts. The results of the antibacterial assays indicated that all tested extracts exert antibacterial activities, with the minimum inhibitory concentration (MIC) values varying from 32 to 1024 μg/ml. The extracts from Dichrostachys glomerata, Beilschmiedia cinnamomea, Aframomum citratum, Piper capense, Echinops giganteus, Fagara xanthoxyloïdes and Olax subscorpioïdea were the most active. In the presence of efflux pump inhibitor, PAßN, the activity of the extract from D. glomerata significantly increased on 69.2% of the tested MDR bacteria. At MIC/5, synergistic effects were noted with the extract of D. glomerata on 75% of the tested bacteria for chloramphenicol (CHL), tetracycline (TET) and norfloxacin (NOR). With B. cinnamomea synergy were observed on 62.5% of the studied MDR bacteria with CHL, cefepime (FEP), NOR and ciprofloxacin (CIP) and 75% with erythromycin (ERY).

Conclusion

The overall results provide information for the possible use of the studied extracts of the spices in the control of bacterial infections involving MDR phenotypes.