PseudomonasSurgical-Site Infections Linked to a Healthcare Worker With Onychomycosis

Pseudomonas aeruginosa Bacteriophages and Their Clinical Applications

Antimicrobial resistance poses a serious risk to contemporary healthcare since it reduces the number of bacterial illnesses that may be treated with antibiotics, particularly for patients with long-term conditions like cystic fibrosis (CF). People with a genetic predisposition to CF often have recurrent bacterial infections in their lungs due to a buildup of sticky mucus, necessitating long-term antibiotic treatment. Pseudomonas aeruginosa infections are a major cause of CF lung illness, and P. aeruginosa airway isolates are frequently resistant to many antibiotics. Bacteriophages (also known as phages), viruses that infect bacteria, are a viable substitute for antimicrobials to treat P. aeruginosa infections in individuals with CF. Here, we reviewed the utilization of P. aeruginosa bacteriophages both in vivo and in vitro, as well as in the treatment of illnesses and diseases, and the outcomes of the latter.

Pseudomonas aeruginosa: Infections and novel approaches to treatment "Knowing the enemy" the threat of Pseudomonas aeruginosa and exploring novel approaches to treatment

Pseudomonas aeruginosa is an aerobic Gram-negative rod-shaped bacterium with a comparatively large genome and an impressive genetic capability allowing it to grow in a variety of environments and tolerate a wide range of physical conditions. This biological flexibility enables the P. aeruginosa to cause a broad range of infections in patients with serious underlying medical conditions, and to be a principal cause of health care associated infection worldwide. The clinical manifestations of P. aeruginosa include mostly health care associated infections and community-acquired infections. P. aeruginosa possesses an array of virulence factors that counteract host defence mechanisms. It can directly damage host tissue while utilizing high levels of intrinsic and acquired antimicrobial resistance mechanisms to counter most classes of antibiotics. P. aeruginosa co-regulates multiple resistance mechanisms by perpetually moving targets poses a significant therapeutic challenge. Thus, there is an urgent need for novel approaches in the development of anti-Pseudomonas agents. Here we review the principal infections caused by P. aeruginosa and we discuss novel therapeutic options to tackle antibiotic resistance and treatment of P. aeruginosa infections that may be further developed for clinical practice.

Onychomycosis Coinfected with Pseudomonas aeruginosa: Report of Four Cases

Patients presenting with green nail syndrome often show coinfection with fungus. A delay in the accurate diagnosis of coinfection may warrant longer treatment duration. Four patients with green nail syndrome coinfected with fungus were reviewed retrospectively. Fungal culture, cultivating Candida parapsilosis and Candida albicans, was performed in two patients' samples. The mean time of the initiation of treatment for onychomycosis after the first visit was 5.75 weeks. If green nail syndrome is suspected, screening for fungal coinfections and precise management are necessary.

Pseudomonas aeruginosa Outbreak in a Neonatal Intensive Care Unit Attributed to Hospital Tap Water

OBJECTIVE To investigate an outbreak of Pseudomonas aeruginosa infections and colonization in a neonatal intensive care unit. DESIGN Infection control assessment, environmental evaluation, and case-control study. SETTING Newly built community-based hospital, 28-bed neonatal intensive care unit. PATIENTS Neonatal intensive care unit patients receiving care between June 1, 2013, and September 30, 2014. METHODS Case finding was performed through microbiology record review. Infection control observations, interviews, and environmental assessment were performed. A matched case-control study was conducted to identify risk factors for P. aeruginosa infection. Patient and environmental isolates were collected for pulsed-field gel electrophoresis to determine strain relatedness. RESULTS In total, 31 cases were identified. Case clusters were temporally associated with absence of point-of-use filters on faucets in patient rooms. After adjusting for gestational age, case patients were more likely to have been in a room without a point-of-use filter (odds ratio [OR], 37.55; 95% confidence interval [CI], 7.16-∞). Case patients had higher odds of exposure to peripherally inserted central catheters (OR, 7.20; 95% CI, 1.75-37.30) and invasive ventilation (OR, 5.79; 95% CI, 1.39-30.62). Of 42 environmental samples, 28 (67%) grew P. aeruginosa. Isolates from the 2 most recent case patients were indistinguishable by pulsed-field gel electrophoresis from water-related samples obtained from these case-patient rooms. CONCLUSIONS This outbreak was attributed to contaminated water. Interruption of the outbreak with point-of-use filters provided a short-term solution; however, eradication of P. aeruginosa in water and fixtures was necessary to protect patients. This outbreak highlights the importance of understanding the risks of stagnant water in healthcare facilities. Infect Control Hosp Epidemiol 2017;38:801-808.

Lack of Comprehensive Outbreak Detection in Hospitals

Timely identification of outbreaks of hospital-associated infections is needed to implement control measures and minimize impact. Survey results from 33 hospitals indicated that most hospitals lacked a formal cluster definition and all targeted a very limited group of prespecified pathogens. Standardized, statistically based outbreak detection could greatly improve current practice.

Do Longer Surgical Procedures Result in Greater Contamination of Surgeons' Hands?

BACKGROUND

A surgical site infection is a substantial cause of complications in patients. Different methods are being used to decrease surgical site infections; however, these infections still can cause complications, especially in patients undergoing longer operations (> 3 hours). There is evidence that the efficacy of the scrubbing material fades after 3 hours. However, we do not know the longevity of hand cleanliness after application of scrubbing materials in a long operation. It can be postulated that if the surgeon's scrubbed hands are recolonized after a certain time, they may serve as a progressive source of contamination during surgery.

QUESTIONS/PURPOSES

We asked: (1) Is there a correlation between surgical duration and hand contamination at the end of surgery? (2) At what point during surgery does hand contamination reach or exceed prescrub levels?

METHODS

Three spine surgeons using the same scrubbing technique and materials consisting of chlorhexidine gluconate 1% solution and ethyl alcohol 61% w/w were enrolled in our study. Between December 2014 and April 2015, spine procedures of 3 hours or more, which were the first case of the day, were selected for this study (20 cases). Cases in which glove changing occurred (perforations, reprepping, and redraping) or cultures obtained after scrubbing were positive (indicative of insufficient hand sanitization) were excluded (0% of cases). Twenty cases (100% enrollment) were analyzed. Surgeons' hands were swabbed with sterile cotton tip applicators and 5 mL sterile phosphate-buffered saline before hand scrubbing (prescrub), immediately after hand scrubbing (postscrub), and immediately after surgery (postoperative). Results were reported in colony-forming units per milliliter. The correlation between duration of surgery and hand recontamination was tested by regression analysis of time versus colony-forming units per milliliter. Receiver-operating characteristic curve tested the cutoff point, where recontamination occurred.

RESULTS

With a longer duration of surgery, more colony-forming units are recovered from gloved hands at the end of surgery (R = 0.94, R(2) = 0.89, p = 0.005). The receiver-operating characteristic curve suggested that 5 hours is the cutoff point for hand recolonization. At 5 hours, contamination reached or exceeded prescrub levels (area under the curve, 0.66; 95% CI, 0.23-1.0), whereas before 5 hours, there was no contamination detected at the end of surgery.

CONCLUSIONS

Our results show that duration of surgery correlates with hand recontamination and at 5 hours, recolonization of a surgeon's hands become detectable. Recolonization may have started even earlier than 5 hours. However, these levels are not detectable in the laboratory at earlier times.

CLINICAL RELEVANCE

Based on this pilot study, rescrubbing is highly recommended before the fifth hour of an operation, ideally at some point between the fourth and fifth hours.

FUTURE

We also recommend the surgical site infection rates in operations using rescrubbing should be compared with those from surgeries with just the conventional single-scrubbing technique, in a randomized controlled trial, to determine the effectiveness of this novel rescrubbing method.

Adherence to surgical hand rubbing directives in a hospital district of Southwest Finland

BACKGROUND

The primary objective was to measure the compliance with alcohol-based surgical hand rubbing (SHR) among operation room personnel. The secondary objective was to evaluate the effect of feedback sessions on compliance.

METHODS

This was a prospective observational before-after intervention study. Between October 2010 and June 2012 the hygiene nurses observed SHR among operation room personnel in the hospital district of Southwest Finland. After feedback sessions a second observation round was conducted in the main operation room of Turku University Hospital. The first observation round comprised 477 observations: 259 (54%) were doctors, 190 (40%) nurses and 28 (5%) other personnel. In the second observation round a total of 210 observations were made.

RESULTS

During the first round in 42% of observations the 3 min SHR time recommended by WHO was used. Median times for SHR were 1 min 50 s (range 0 min to 5 min 44 s) for doctors and 3 min 25 s (range 1 min 1 s to 8 min 15 s) for nurses, respectively (p < 0.0001). In 40% of observations hands were not properly dried after a wash before applying SHR and in 45% hands were not allowed to dry properly after SHR before donning surgical gloves. After feedback, time for SHR did not significantly improve but technique did.

CONCLUSIONS

SHR was performed incorrectly in most observations even after feedback. The results stress the importance of more effective education, helping techniques and positive role models for operation room personnel to promote SHR.

An Outbreak ofPseudomonas aeruginosaPneumonia and Bloodstream Infection Associated With Intermittent Otitis Externa in a Healthcare Worker

Objectives:

To investigate an outbreak ofPseudomonas aeruginosapneumonia and bloodstream infection among four neonates, determine risk factors for infection, and implement preventive strategies.

Design:

Retrospective case finding; prospective surveillance cultures of patients, personnel, and environmental sites; molecular typing by pulsed-field gel electrophoresis; and a matched case-control study.

Patients and Setting:

Neonates in the level-III neonatal intensive care unit of a tertiary-care pediatric institution.

Interventions:

Cohorting of patients with positive results forP. aeruginosa, work restrictions for staff with positive results, implementation of an alcohol-based hand product, review of infection control policies and procedures, and closure of the unit until completion of the investigation.

Results:

Seven (4%) of 190 environmental cultures and 5 (3%) of 178 cultures of individual healthcare workers' hands grewP. aeruginosa. All four outbreak isolates and one previous bloodstream isolate were genotypically identical, as were theP. aeruginosaisolates from the hands and external auditory canal of a healthcare worker with intermittent otitis externa. Four of 5 case-patients versus 5 of 15 matched control-patients had been cared for by this healthcare worker (P= .05). The healthcare worker was treated and no further cases occurred.

Conclusions:

These findings suggest that a healthcare worker with intermittent otitis externa may have caused this cluster of fatalP. aeruginosainfections, adding the external ear to the list of colonized body sites that may serve as a source of potentially pathogenic organisms.

[Infections of finger and toe nails due to fungi and bacteria]

Infections of the finger and the toe nails are most frequently caused by fungi, primarily dermatophytes. Causative agents of tinea unguium are mostly anthropophilic dermatophytes. Both in Germany, and worldwide, Trichophyton rubrum represents the main important causative agent of onychomycoses. Yeasts are isolated from fungal nail infections, both paronychia and onychomycosis far more often than generally expected. This can represent either saprophytic colonization as well as acute or chronic infection of the nail organ. The main yeasts causing nail infections are Candida parapsilosis, and Candida guilliermondii; Candida albicans is only in third place. Onychomycosis due to molds, or so called non-dermatophyte molds (NDM), are being increasingly detected. Molds as cause of an onychomycosis are considered as emerging pathogens. Fusarium species are the most common cause of NDM onychomycosis; however, rare molds like Onychocola canadensis may be found. Bacterial infections of the nails are caused by gram negative bacteria, usually Pseudomonas aeruginosa (recognizable because of green or black coloration of the nails) but also Klebsiella spp. and gram positive bacteria like Staphylococcus aureus. Treatment of onychomycosis includes application of topical antifungal agents (amorolfine, ciclopirox). If more than 50 % of the nail plate is affected or if more than three out of ten nails are affected by the fungal infection, oral treatment using terbinafine (in case of dermatophyte infection), fluconazole (for yeast infections), or alternatively itraconazole are recommended. Bacterial infections are treated topically with antiseptic agents (octenidine), and in some cases with topical antibiotics (nadifloxacin, gentamicin). Pseudomonas infections of the nail organ are treated by ciprofloxacin; other bacteria are treated according to the results of culture and sensitivity testing.

Green Nail Syndrome (Pseudomonas aeruginosa Nail Infection): Two Cases Successfully Treated with Topical Nadifloxacin, an Acne Medication

Green nail syndrome (GNS) caused by Pseudomonas aeruginosa is the most common bacterial nail infection. The treatment of GNS is challenging in many cases and recommendations based on clinical trials are lacking. We report two cases with GNS successfully treated with off-label use of topical nadifloxacin, a fluoroquinolone approved for acne and bacterial skin infections in some countries.

Risk Factors for Postoperative Chest Wound Infections Due to Gram-negative Bacteria in Cardiac Surgery Patients

Gram-negative bacteria account for up to 35% of postoperative sternal wound infections (SWI) in patients undergoing cardiac surgery. Despite this, risk factors for Gram-negative SWI have not been investigated. The objective of this study was to define risk factors associated with Gram-negative SWI in patients undergoing cardiac surgery. 2590 patients undergoing cardiac surgery between 2002-2005 were prospectively monitored for development of SWI. Patient, operative, and post-operative risk factors were compared among patients that developed Gram-negative SWI and Gram-positive SWI to uninfected controls using univariate and multivariate analysis. A p < 0.05 was considered significant. Surgical site infections developed in 152 (5.9%) patients. Isolates were recovered from the sternum for 128 (5.0%) patients, from the leg donor site for 19 (0.73%) patients, and from the sternum and donor site for 5 (0.19%) patients. Gram-positive pathogens were isolated from 83 (3.3%) patients, Gram-negative pathogens from 42 (1.6%) patients, and mixed pathogens from 27 (1.0%) patients. Hospital admission greater than 48 hours before surgery (OR: 2.25; 95% CI: 1.11 - 4.58), ventilator-dependency preoperatively (OR: 5.32 95% CI: 2.22 - 12.75), and thoracentesis procedure postoperatively (OR: 3.71; 95% CI: 1.45 - 9.49) and diabetes (OR: 2.04; 95% CI: 1.17 - 3.55) were identified as significant risk factors for SWI due to Gram-negative bacteria using multivariate logistic regression. Diabetes, increased age, and peripheral vascular disease were identified as significant risk factors for SWI due to Gram-positive bacteria (p < 0.05, each). The risk factors associated with Gram-negative SWI differed significantly from those associated with Gram-positive SWI. Risk factors associated with Gram-negative SWI were identified. Unique interventions may be necessary to prevent Gram-negative SWI in cardiac surgery patients.

Prospective, randomized in vivo comparison of a dual-active waterless antiseptic versus two alcohol-only waterless antiseptics for surgical hand antisepsis

BACKGROUND

This study aimed to demonstrate the value of adding an active level of a persistent antimicrobial agent, such as chlorhexidine gluconate (CHG), to an alcohol-based surgical hand antiseptic.

METHODS

The persistence of 3 waterless, brushless alcohol-based surgical hand antiseptics, including one product containing CHG, was compared. The test products were applied a total of 12 times over 5 days. Samples of aerobic bacteria were collected on days 1 and 5, on both days immediately after drying and 6 hours later, using the glove juice technique. Relative suppression of regrowth was compared using t tests.

RESULTS

Using an equivalence margin of 20%, the alcohol plus CHG product showed noninferiority to the alcohol-only products at all sampling points and, based on significantly lower bacterial regrowth (P = .026), superior persistence to the alcohol-only products after 6 hours of glove wear.

CONCLUSIONS

Given the primary objective of surgical hand antisepsis of reducing resident skin flora for the duration of the surgical procedure, using an alcohol-based hand antiseptic containing CHG appears to be the most appropriate choice for maintaining microbial levels as low as possible for as long as possible.

Point-of-use water filtration reduces endemic Pseudomonas aeruginosa infections on a surgical intensive care unit

BACKGROUND

Endemic infections because of Pseudomonas aeruginosa were observed on a surgical intensive care unit (ICU) for a period of >24 months. Tap water probing revealed persistent colonization of all ICU water taps with a single P aeruginosa clonotype.

METHODS

Water outlets of the ICU were equipped with disposable point-of-use water filters, changed in weekly and, later, 2-week intervals. To delineate the effect of the filters, 4 study approaches were followed: (1) a descriptive analysis of the incidence of P aeruginosa colonizations and infections, (2) microbiologic examinations of tap water before and after installation of the filters, (3) a comparative cohort analysis of representative patient samples from the prefilter and postfilter time periods, and (4) an analysis of general ward variables for the 2 periods.

RESULTS

(1) The mean monthly rate (+/-SD) of P aeruginosa infection/colonization episodes was 3.9 +/- 2.4 in the prefilter and 0.8 +/- 0.8 in the postfilter period. P aeruginosa colonizations were reduced by 85% (P < .0001) and invasive infections by 56% (P < .0003) in the postfilter period. (2) Microbiologic examinations of tap water revealed growth of P aeruginosa in 113 of 117 (97%) samples collected during the prefilter period, compared with 0 of 52 samples taken from filter-equipped taps. (3) In the comparative cohort analysis, a number of patient-related variables were significantly associated with P aeruginosa colonization/infection. Considering these variables in a multivariate analysis, belonging to the postfilter cohort was the factor most strongly associated with a reduced risk of P aeruginosa positivity (relative risk, 0.04; P = .0002). (4) General ward variables such as bed occupancy, personnel-to-patient ratio, or microbiologic culturing density did not differ significantly between the 2 periods.

CONCLUSION

Taking into account various patient-related and general ward variables, point-of-use water filtration was associated with a significant reduction of chronically endemic P aeruginosa colonizations/infections on a surgical ICU.

Evidence-based model for hand transmission during patient care and the role of improved practices

Hand cleansing is the primary action to reduce health-care-associated infection and cross-transmission of antimicrobial-resistant pathogens. Patient-to-patient transmission of pathogens via health-care workers' hands requires five sequential steps: (1) organisms are present on the patient's skin or have been shed onto fomites in the patient's immediate environment; (2) organisms must be transferred to health-care workers' hands; (3) organisms must be capable of surviving on health-care workers' hands for at least several minutes; (4) handwashing or hand antisepsis by the health-care worker must be inadequate or omitted entirely, or the agent used for hand hygiene inappropriate; and (5) the caregiver's contaminated hand(s) must come into direct contact with another patient or with a fomite in direct contact with the patient. We review the evidence supporting each of these steps and propose a dynamic model for hand hygiene research and education strategies, together with corresponding indications for hand hygiene during patient care.

Nosocomial outbreak of Pseudomonas aeruginosa infections related to a flexible bronchoscope

An outbreak of Pseudomonas aeruginosa infections affecting 17 patients was detected in the 27-bed intensive care unit (ICU) of a community hospital from 1 July to 30 September 2003. An ambidirectional cohort study was conducted to identify the risk factors for infection. Nosocomial infections were defined using the criteria of the Centers for Disease Control and Prevention. Random arbitrary polymorphic DNA-polymerase chain reaction was used for genotypic characterization. Logistic regression analyses demonstrated that case patients were more likely than non-cases to have had a longer stay in the ICU, and to have undergone mechanical ventilation and antimicrobial treatment. The multi-variate analysis identified recent bronchoscopy [risk ratio (RR) 3.8, 95% confidence interval (CI) 2.5-3.9] and exposure to an infected patient (RR 2.9, 95% CI 1.1-3.7) as independent risk factors. Molecular analysis showed that of the nine isolates available, four patients had a similar strain. The factor with the strongest influence on the risk of death was infection with P. aeruginosa (RR 2.1, 95% CI 1.0-2.4, P=0.04). A combined infection control strategy was implemented, including strict compliance with isolation precautions and recommendations for cleaning and disinfecting bronchoscopes, and a sharp reduction in the incidence of P. aeruginosa infection followed. It is thought that this outbreak was caused by patient-to-patient transmission and infection from a common source, i.e. the flexible bronchoscope.

Postoperative Wundinfektionen

Surgical site infections can be traced to discrepancies in one specific hospital department: the operating suite. Therefore, prevention is often viewed as resting completely on the surgeon. However, the source of micro-organisms responsible for surgical site infections can be endogenous or exogenous. Most infections are believed to be the former, i.e. caused by micro-organisms already resident in the patient's body. Therefore the surgeon can be regarded as suspect only in exceptional cases and usually himself a victim. Prevention is possible not only for exogenous surgical site infection but also many endogenous infections. A multicenter surveillance of infection rates at 130 operative departments participating for at least 4 years in the German National Nosocomial Infection Surveillance System was conducted. A significant 25% reduction in the 3rd year was observed compared with patients who underwent surgery within the 1st year of participation. However, surgeons alone cannot achieve such a decrease, and a team approach is required under most circumstances.

Forty-eight-hour diagnosis of onychomycosis with subtyping of Trichophyton rubrum strains

A novel strategy for the molecular identification of fungal agents of onychomycosis (including Trichophyton rubrum) has been designed based on the use of species-specific and universal primers in conjunction with a commercial kit that allows the extraction of DNA directly from the nail specimens. The microsatellite marker T1, which is based on a (GT)n repeat, was applied for the species-specific identification of Trichophyton rubrum. To evaluate how often Scopulariopsis spp. are detected in nail specimens, a second primer pair was designed to amplify specifically a 336-bp DNA fragment of the 28S region of the nuclear rRNA gene of S. brevicaulis and closely related species. Other fungal species were identified using amplification of the internal transcribed spacer (ITS) region of the rRNA gene, followed by restriction fragment length polymorphism analysis or sequencing. In addition, polyacrylamide gel separation of the T1-PCR product allowed subtyping of T. rubrum strains. We studied 195 nail specimens (the "nail sample") and 66 previously collected etiologic strains (the "strain sample") from 261 onychomycosis patients from Bulgaria and Greece. Of the etiologic agents obtained from both samples, T. rubrum was the most common organism, confirmed to be present in 76% of all cases and serving as the sole or (rarely) mixed etiologic agent in 199 of 218 cases (91%) where the identity of the causal organism(s) was confirmed. Other agents seen included molds (6% of cases with identified etiologic agents; mainly S. brevicaulis) and other dermatophyte species (4%; most frequently Trichophyton interdigitale). Simultaneous infections with two fungal species were confirmed in a small percentage of cases (below 1%). The proportion of morphologically identified cultures revealed by molecular study to have been misidentified was 6%. Subtyping revealed that all but five T. rubrum isolates were of the common type B that is prevalent in Europe. In comparison to microscopy and culture, the molecular approach was superior. The PCR was more sensitive (84%) than culture (22%) in the nail sample and was more frequently correct in specifically identifying etiologic agents (100%) than microscopy plus routine culture in either the nail or the strain samples (correct culture identifications in 96% and 94% of cases, respectively). Using the molecular approach, the time for diagnosing the identity of fungi causing onychomycosis could be reduced to 48 h, whereas culture techniques generally require 2 to 4 weeks. The early detection and identification of the infecting species in nails will facilitate prompt and appropriate treatment and may be an aid for the development of new antifungal agents.

A Systematic Review of Quasi-Experimental Study Designs in the Fields of Infection Control and Antibiotic Resistance

We performed a systematic review of articles published during a 2-year period in 4 journals in the field of infectious diseases to determine the extent to which the quasi-experimental study design is used to evaluate infection control and antibiotic resistance. We evaluated studies on the basis of the following criteria: type of quasi-experimental study design used, justification of the use of the design, use of correct nomenclature to describe the design, and recognition of potential limitations of the design. A total of 73 articles featured a quasi-experimental study design. Twelve (16%) were associated with a quasi-experimental design involving a control group. Three (4%) provided justification for the use of the quasi-experimental study design. Sixteen (22%) used correct nomenclature to describe the study. Seventeen (23%) mentioned at least 1 of the potential limitations of the use of a quasi-experimental study design. The quasi-experimental study is used frequently in studies of infection control and antibiotic resistance. Efforts to improve the conduct and presentation of quasi-experimental studies are urgently needed to more rigorously evaluate interventions.