Initial waterline contamination by Pseudomonas aeruginosa in newly installed dental chairs

Water contamination in dental unit waterlines (DUWLs) is a potential source of healthcare-associated infection during dental care. The aim of this study was to evaluate the microbiological quality of DUWLs water from newly installed dental chairs in a French University Hospital. The microbiological quality of water from 24 new DUWLs initially disinfected by ICX Renew-prior to use of the dental units for patient treatment-was assessed for total culturable aerobic bacteria at 22°C and 36°C, Legionella sp., Pseudomonas aeruginosa, and total coliforms. Among the 24 samples analyzed, 21 were compliant with the water quality levels: 19 had no bacteria, and 2 contained only 4 and 1 CFU/mL for total culturable aerobic bacteria at 22°C and 36°C, respectively. Three samples were non-compliant due to contamination by P. aeruginosa (4, 2, and 2 CFU/100 mL). Controlling and preventing the microbiological contamination of DUWLs, especially by pathogenic bacteria, at the time of the installation of the new dental chairs are crucial to prevent healthcare-associated infection in dentistry.

IMPORTANCE

Dental unit waterlines (DUWLs) of new dental chairs may be contaminated before their first clinical use, so an initial shock disinfection is crucial at the time of their installation. The microbiological analyses are crucial to control the water quality of DUWLs before their first clinical use because their disinfection does not guarantee the elimination of all bacteria.

[Effect of Using Hydrogen Peroxide for Periodic Disinfection Combined With Continuous Disinfection to Control Contamination in Dental Unit Waterline]

Objective

To observe the effect of using hydrogen peroxide in periodic disinfection combining with continuous disinfection of dental unit waterlines and to provide references for the selection of waterway disinfection measures.

Methods

A total of 4 dental units in a hospital of stomatology were selected through convenience sampling. The dental unit waterlines received periodic disinfection once every 4 weeks in addition to continuous disinfection (When the dental units were not used for more than 3 days, an additional periodic disinfection would be performed.). Periodic disinfection referred to filling up the waterlines with a disinfectant solution (1.4% hydrogen peroxide) by using the waterline disinfection device that came with the dental unit, immersing for 24 hours, and then emptying out the disinfectant solution. Continuous disinfection referred to using hydrogen peroxide at a concentration of 0.014% as dental treatment water and using it to flush the waterlines for 2 minutes before any dental treatment in the morning and to flush the waterlines for 30 seconds after each dental treatment. The study lasted for 25 weeks, with periodic disinfection being performed for 7 times and continuous disinfection carried out for the rest of the dental treatment time. During the 25 weeks, water samples were collected from air/water syringes and high-speed handpieces. Then, the water samples were incubated and the bacterial concentration and the qualification rates were calculated accordingly. When the bacterial concentration≤100 CFU/ mL, the water samples were considered to be qualified. Waterline tubes of 1 cm were collected before and after the 25 weeks of disinfection with hydrogen peroxide. Biofilms in the waterline tube were observed under scanning electron microscope.

Results

A total of 352 water samples were collected. Eight water samples were collected before disinfection with hydrogen peroxide, with the median of bacterial concentration being 3140 CFU/mL. On the first day of disinfection with hydrogen peroxide, the median bacterial concentration in dental treatment water was 7.5 CFU/mL. There was a significant difference between the bacterial concentration of the water samples before the disinfection and that after the disinfection (P=0.012). A total of 344 water samples were collected after the disinfection, with the median bacterial concentrations for air/water syringes and high-speed handpieces being 11 CFU/mL and 11CFU/mL and the qualified rates being 83.7% and 82.0%, respectively. There was no significant difference in bacterial concentration or the qualification rates. During week 1 through week 9 of the disinfection, the qualification rates of the dental treatment water always exceeded 80% in 8 weeks, with week 3 being the exception. In the two four-week disinfection periods of week 14 through week 17 and week 18 through week 21, the qualification rate was maintained at above 80% for only the first two weeks and started to decrease from the third week. Biofilm morphology was observed under scanning electron microscope. Before the disinfection, the biofilm was found to be a dense structure and the mixture of a large number of bacteria. After 25 weeks of the disinfection, the biofilm structure appeared to be loose and did not show consistent characteristics of a large number of bacteria retained.

Conclusion

Periodic disinfection combined with continuous disinfection using hydrogen peroxide can effectively control contamination in dental unit waterlines. But the cycles of periodic disinfection and the concentration of hydrogen peroxide for continuous disinfection should be further discussed according to the actual clinical situation.

The importance of biofilm contamination control for dental unit waterlines: a multicenter assessment of the microbiota diversity of biofilm in dental unit waterlines

Background

The biofilm formation in Dental Unit Waterlines (DUWLs) could become an important cause of infection during dental care, which could put immunocompromised individuals at risk of cross-infection. The aim of this study was to characterize the microbial communities of biofilms among DUWLs using high-throughput sequencing technology.

Methods

Twenty-nine biofilm samples were obtained from 24 dental chair units at 5 hospitals and 2 dental clinics. The genomic DNA of the samples was extracted, then 16S rDNA and ITS2 gene were amplified and sequenced. Alpha-diversity and Beta-diversity were calculated with QIIME2 and the Kruskal - Wallis H-test was adopted for statistical analysis.

Results

Microbial communities with a high diversity of bacteria (377 genera) and fungi (83 genera) were detected in the biofilm samples. The dominant phylum of bacteria was Proteobacteria (93.27%) and that of fungi was Basidiomycota (68.15%). Potential human pathogens were detected including 7 genera of bacteria (Pseudomonas, Stenotrophomonas, Hafnia-Obesumbacterium, Burkholderia-Caballeronia-Paraburkholderia, Ralstonia, Enterobacter, Klebsiella) and 6 genera of fungi (Malassezia, Candida, Alternaria, Cryptococcus, Rhodotorula, Rhinocladiella).

Conclusions

This multicenter assessment revealed the infectious risk during dental care. It emphasized the importance of biofilm control due to biofilm accumulation and multiple kinds of opportunistic pathogens in DUWLs.

Dental unit waterline testing practices: an 11-Year retrospective study

OBJECTIVES

This retrospective study examined the dental unit waterline (DUWL) testing practices of Saskatchewan dental clinics over a period of 11 years, with an emphasis on their responses after identification of high microbial levels.

MATERIALS AND METHODS

Dental clinics (n = 137) aseptically collected samples of output water from their air/water syringes, handpieces, and ultrasonic scaler lines using Sigma-Aldrich® waterline test kits and delivered them to a quality assurance laboratory. Tests were incubated for seven days at room temperature, and those with heterotrophic plate counts > 500 CFU/mL were reported as failures. Statistical analyses were performed on a database containing 4,093 test results.

RESULTS

Participating clinics submitted an average of 11 DUWL tests per year. Overall, 21% of tests failed, and a moderate positive association (rs=.52, p < 0.001) was found between clinics' DUWL testing frequency and failure rate. Only 7% of failed DUWL tests were followed up by collection of a subsequent test within two weeks, of which 47% still exceeded the 500 CFU/mL threshold.

CONCLUSIONS

Our findings demonstrate an association between DUWL testing frequency and detection of unacceptable microbial levels, along with infrequent retesting and often-inadequate intervention after a failed test. This suggests the need for further efforts at the regulatory and educational levels to maintain adequate water quality during dental treatment.

CLINICAL RELEVANCE

Procedural water can become contaminated in DUWLs and endanger patients. Regular DUWL monitoring and evidence-based interventions to treat contaminated systems are necessary to safeguard patient health.

Epidemiology of Pulmonary and Extrapulmonary Nontuberculous Mycobacteria Infections at 4 US Emerging Infections Program Sites: A 6-Month Pilot

BACKGROUND

Nontuberculous mycobacteria (NTM) cause pulmonary (PNTM) and extrapulmonary (ENTM) disease. Infections are difficult to diagnose and treat, and exposures occur in healthcare and community settings. In the United States, NTM epidemiology has been described largely through analyses of microbiology data from health departments, electronic health records, and administrative data. We describe findings from a multisite pilot of active, laboratory- and population-based NTM surveillance.

METHODS

The Centers for Disease Control and Prevention's Emerging Infections Program conducted NTM surveillance at 4 sites (Colorado, 5 counties; Minnesota, 2 counties; New York, 2 counties; and Oregon, 3 counties [PNTM] and statewide [ENTM]) from 1 October 2019 through 31 March 2020. PNTM cases were defined using published microbiologic criteria. ENTM cases required NTM isolation from a nonpulmonary specimen, excluding stool and rectal swabs. Patient data were collected via medical record review.

RESULTS

Overall, 299 NTM cases were reported (PNTM: 231, 77%); Mycobacterium avium complex was the most common species group. Annualized prevalence was 7.5/100 000 population (PNTM: 6.1/100 000; ENTM: 1.4/100 000). Most patients had signs or symptoms in the 14 days before positive specimen collection (ENTM: 62, 91.2%; PNTM: 201, 87.0%). Of PNTM cases, 145 (62.8%) were female and 168 (72.7%) had underlying chronic lung disease. Among ENTM cases, 29 (42.6%) were female, 21 (30.9%) did not have documented underlying conditions, and 26 (38.2%) had infection at the site of a medical device or procedure.

CONCLUSIONS

Active, population-based NTM surveillance will provide data for monitoring the burden of disease and characterize affected populations to inform interventions.

A novel chemogenomic discovery platform identifies bioactive hits with rapid bactericidal activity against Mycobacteroides Abscessus

Mycobacteroides abscessus (M. ab) infections are innately resistant to most currently available antibiotics and present a growing, poorly addressed medical need. The existing treatment regimens are lengthy and produce inadequate outcomes for many patients. Importantly, most clinically used drugs and drug candidates against M. ab are either bacteriostatic, or only weakly bactericidal. New strategies exploring a broader chemical space are urgently needed, as innovative agents in development are scarce and hit rates in large unbiased screens against the mycobacterium have been discouragingly low. Here we present a computational chemogenomics-driven approach to discovery of novel antibacterials that effectively reveals drug-like compounds active against M. ab, paired with small sets of predicted molecular targets for the compounds. Several of the bioactive hits identified exhibited rapid bactericidal, including sterilizing, activity against the mycobacterium, indicating that there are currently unexploited chemically tractable molecular mechanisms for rapid sterilization of M. ab. Interestingly, starvation, which typically induces drug tolerance, sensitized M. ab to some of the compounds, resulting in potencies similar to those of drugs in clinical use. The presented drug discovery platform has potential to identify highly differentiated prototype anti-infective molecules and thereby contribute to development of regimens for shorter treatment and improved outcomes for non-tuberculous mycobacterial infections.

Mycobacterium abscessus Cluster in Cardiac Surgery Patients Potentially Attributable to a Commercial Water Purification System

BACKGROUND

Nontuberculous mycobacteria are water-avid pathogens that are associated with nosocomial infections.

OBJECTIVE

To describe the analysis and mitigation of a cluster of Mycobacterium abscessus infections in cardiac surgery patients.

DESIGN

Descriptive study.

SETTING

Brigham and Women's Hospital, Boston, Massachusetts.

PARTICIPANTS

Four cardiac surgery patients.

INTERVENTION

Commonalities among cases were sought, potential sources were cultured, patient and environmental specimens were sequenced, and possible sources were abated.

MEASUREMENTS

Description of the cluster, investigation, and mitigation.

RESULTS

Whole-genome sequencing confirmed homology among clinical isolates. Patients were admitted during different periods to different rooms but on the same floor. There were no common operating rooms, ventilators, heater-cooler devices, or dialysis machines. Environmental cultures were notable for heavy mycobacterial growth in ice and water machines on the cluster unit but little or no growth in ice and water machines in the hospital's other 2 inpatient towers or in shower and sink faucet water in any of the hospital's 3 inpatient towers. Whole-genome sequencing confirmed the presence of a genetically identical element in ice and water machine and patient specimens. Investigation of the plumbing system revealed a commercial water purifier with charcoal filters and an ultraviolet irradiation unit leading to the ice and water machines in the cluster tower but not the hospital's other inpatient towers. Chlorine was present at normal levels in municipal source water but was undetectable downstream from the purification unit. There were no further cases after high-risk patients were switched to sterile and distilled water, ice and water machine maintenance was intensified, and the commercial purification system was decommissioned.

LIMITATION

Transmission pathways were not clearly characterized.

CONCLUSION

Well-intentioned efforts to modify water management systems may inadvertently increase infection risk for vulnerable patients.

PRIMARY FUNDING SOURCE

National Institutes of Health.

Paediatric Deep Neck Infection—The Risk of Needing Intensive Care

Deep neck infections are potentially dangerous complications of upper respiratory tract or odontogenic infections. The pathophysiology, clinical presentation, and potential spreading depend on the complex anatomy of the neck fascia. These infections can lead to severe pathological conditions, such as mediastinitis, sepsis, and especially airway impairment with difficult management. Because of the risk of life-threatening emergency situations and the possible impacts on the overall health status of affected children, their early recognition is of utmost importance. Torticollis, drooling, and stridor are the most common signs of advancing disease. Children presenting with these symptoms should be admitted to the paediatric intensive care unit for vital function monitoring, where the airway could be readily secured if function is compromised.

Assessment of microbiota diversity in dental unit waterline contamination

BACKGROUND

Dental unit waterlines (DUWLs) provide water for handpieces, air/water syringes, and mouth-rinse water outlets. DUWL contamination can negatively affect the operating environment and public health. Therefore, it is important to elucidate the bacterial concentrations and microbial composition in the DUWLs from different dental specialties.

METHODS

We collected 350 5-mL dental water samples (from high-speed handpieces, air/water syringes, and mouth-rinse water outlets) from 60 dental chair units (DCUs) at a dental hospital to determine the bacterial concentrations by culture methods. Meanwhile, to investigate the diversity and community structure of microbe in the DUWLs, 17 high-quality DNA from 60 250-mL air/water syringe water samples, which were collected from the same 60 DCUs, were analyzed using 16S rDNA high-throughput sequencing.

RESULTS

The median bacterial concentration was 166 (31.5, 672.5) CFU/mL and the range was 0-3,816,000 CFU/mL. Only 42.6% of the water samples had bacterial concentrations below 100 CFU/mL. The Kruskal-Wallis H-test revealed that the water samples from three dental specialties had significantly different bacterial concentrations (H = 27.441, P < 0.01). High-throughput sequencing results showed significant differences in bacterial community structure between periodontics and the other two dental specialties. In the samples from three dental specialties, 508 OTUs were detected, with 160, 182 and 176 OTUs unique to the periodontics, endodontics and prosthodontics specialties, respectively. Linear discriminant analysis (LDA) effect size (LEfSe) suggested that Hydrocarboniphaga, Zoogloea, Aquabacterium, and Hydrogenophaga were enriched in the periodontics specialty; Acinetobacter, Geothrix, and Desulfovibrio were enriched in the prosthodontics specialty; and Alistipes, Clostridium XIVa, and Serratia were enriched in the endodontics specialty. Seven potentially human-pathogenic genera (Pseudomonas, Acinetobacter, Sphingomonas, Ochrobactrum, Rhizobium, Brevundimonas, and Methylobacterium) with relative abundance exceeding 1% were also detected in the DUWLs.

CONCLUSIONS

The bacterial concentrations and microbial composition were influenced by different dental specialties, so a validated disinfection protocol should be used to control DUWL contamination in different dental specialties.

Water Safety and Health Care: Preventing Infections Caused by Opportunistic Premise Plumbing Pathogens

Health care facility water systems have been associated with the transmission of opportunistic premise plumbing pathogens such as Legionella and nontuberculous mycobacteria. These pathogens can enter a building's water system in low numbers and then proliferate when conditions are conducive to their growth. Patients and residents in health care facilities are often at heightened risk for opportunistic infections, and cases and outbreaks in the literature highlight the importance of routine water management programs and occasions for intervention to prevent additional cases. A multidisciplinary proactive approach to water safety is critical for sustained prevention of health care-associated water-related infections.

A Molecular-Beacon-Based Multiplex Real-Time PCR Assay To Distinguish Mycobacterium abscessus Subspecies and Determine Macrolide Susceptibility

Mycobacterium abscessus is a rapidly growing nontuberculous mycobacterial species that comprises three subspecies: M. abscessus subsp. abscessus, M. abscessus subsp. massiliense, and M. abscessus subsp. bolletii. These predominantly environmental microorganisms have emerged as life-threatening chronic pulmonary pathogens in both immunocompetent and immunocompromised patients, and their acquisition of macrolide resistance due to the erm(41) gene and mutations in the 23S rrl gene has dramatically impacted patient outcome. However, standard microbiology laboratories typically have limited diagnostic tools to distinguish M. abscessus subspecies, and the testing for macrolide resistance is often not done. Here, we describe the development of a real-time multiplex assay using molecular beacons to establish a robust, rapid, and highly accurate method to both distinguish M. abscessus subspecies and to determine which strains are susceptible to macrolides. We report a bioinformatic approach to identify robust subspecies sequence targets, the design and optimization of six molecular beacons to identify all genotypes, and the development and application of a 2-tube 3-color multiplex assay that can provide clinically significant treatment information in less than 3 h.

Pulmonary Mycobacterium abscessus Infection in an 11-Year-Old Child, Successfully Treated with Inhaled/Parenteral Amikacin: A Case Report and Review of Literature

Mycobacterium abscessus appears to be increasing cause of pulmonary infection in children with underlying risk factors including cystic fibrosis, chronic lung disease and immunodeficiency syndromes. We present a case of pulmonary M. abscessus infection in a pediatric patient with primary ciliary dyskinesia and he was successfully treated with parenteral amikacin, linezolid and oral clarithromycin combined with inhaled amikacin. Clinical improvement was observed after adding inhaled amikacin to the treatment.

Characterization of Biofilm Formation by Mycobacterium chimaera on Medical Device Materials

Non-tuberculous mycobacteria (NTM) are widespread in the environment and are a public health concern due to their resistance to antimicrobial agents. The colonization of surgical heater-cooler devices (HCDs) by the slow-growing NTM species Mycobacterium chimaera has recently been linked to multiple invasive infections in patients worldwide. The resistance of M. chimaera to antimicrobials may be aided by a protective biofilm matrix of extracellular polymeric substances (EPS). This study explored the hypothesis that M. chimaera can form biofilms on medically relevant materials. Several M. chimaera strains, including two HCD isolates, were used to inoculate a panel of medical device materials. M. chimaera colonization of the surfaces was monitored for 6 weeks. M. chimaera formed a robust biofilm at the air-liquid interface of borosilicate glass tubes, which increased in mass over time. M. chimaera was observed by 3D Laser Scanning Microscopy to have motility during colonization, and form biofilms on stainless steel, titanium, silicone and polystyrene surfaces during the first week of inoculation. Scanning electron microscopy (SEM) of M. chimaera biofilms after 4 weeks of inoculation showed that M. chimaera cells were enclosed entirely in extracellular material, while cryo-preserved SEM samples further revealed that an ultrastructural component of the EPS matrix was a tangled mesh of 3D fiber-like projections connecting cells. Considering that slow-growing M. chimaera typically has culture times on the order of weeks, the microscopically observed ability to rapidly colonize stainless steel and titanium surfaces in as little as 24 h after inoculation is uncharacteristic. The insights that this study provides into M. chimaera colonization and biofilm formation of medical device materials are a significant advance in our fundamental understanding of M. chimaera surface interactions and have important implications for research into novel antimicrobial materials, designs and other approaches to help reduce the risk of infection.

Microbial Contamination of Dental Unit Waterlines and Potential Risk of Infection: A Narrative Review

Several studies have revealed that dental unit waterlines (DUWLs) are often contaminated by large numbers of various micro-organisms (bacteria, fungi, protozoa, viruses). Microbial contamination in DUWLs may originate from the mains water piped into the dental unit, the suck-back of patients' saliva into the line due to the lack of adequate valves, and contamination from bottled water systems. Some of the main determinants of microbial contamination in DUWLs are: a very small lumen size (0.5-2 mm) of the tubing used, high surface-to-volume ratio (6:1), low throughput and the materials of which the tubing is made, water stagnation outside of working hours. The environmental conditions present inside the conduits of the dental unit may facilitate the proliferation of micro-organisms and the consequent formation of biofilm on the interior surface of the pipes of DUWLs. During the use of handpieces, particularly high-speed rotating instruments, a spray is thrown up in the form of aerosols or spatters containing biological material (saliva, blood and dental plaque) and micro-organisms. This means that the health of both dental staff and patients could be at risk of infection. The risk of cross-infections in dental settings can be tackled by implementing combined interventions to prevent the contamination of DUWLs.

Demystifying the mist: Sources of microbial bioload in dental aerosols

The risk of transmitting airborne pathogens is an important consideration in dentistry and has acquired special significance in the context of recent respiratory disease epidemics. The purpose of this review, therefore, is to examine (1) what is currently known regarding the physics of aerosol creation, (2) the types of environmental contaminants generated by dental procedures, (3) the nature, quantity, and sources of microbiota in these contaminants and (4) the risk of disease transmission from patients to dental healthcare workers. Most dental procedures that use ultrasonics, handpieces, air‐water syringes, and lasers generate sprays, a fraction of which are aerosolized. The vast heterogeneity in the types of airborne samples collected (spatter, settled aerosol, or harvested air), the presence and type of at‐source aerosol reduction methods (high‐volume evacuators, low volume suction, or none), the methods of microbial sampling (petri dishes with solid media, filter paper discs, air harvesters, and liquid transport media) and assessment of microbial bioload (growth conditions, time of growth, specificity of microbial characterization) are barriers to drawing robust conclusions. For example, although several studies have reported the presence of microorganisms in aerosols generated by ultrasonic scalers and high‐speed turbines, the specific types of organisms or their source is not as well studied. This paucity of data does not allow for definitive conclusions to be drawn regarding saliva as a major source of airborne microorganisms during aerosol generating dental procedures. Well‐controlled, large‐scale, multi center studies using atraumatic air harvesters, open‐ended methods for microbial characterization and integrated data modeling are urgently needed to characterize the microbial constituents of aerosols created during dental procedures and to estimate time and extent of spread of these infectious agents.

Odontogenic cutaneous sinus tracts due to infection with nontuberculous mycobacteria: a report of three cases

Background

Soft tissue or skin infections due to nontuberculous mycobacteria (NTM) have been reported frequently and are mostly associated with trauma or cosmetic interventions like plastic surgery. However, infection with NTM as a result of a dental procedure have rarely been described and the lack of clinical suspicion and a clear clinical manifestation makes diagnosis challenging.

Case presentation

We report on three patients with a facial cutaneous sinus tract of dental origin, due to an infection with respectively Mycobacterium fortuitum, M. abscessus and M. peregrinum. The infection source was the dental unit waterlines (DUWLs), which were colonized with NTM.

Conclusions

Water of the DUWL can pose a health risk. This report emphasizes the need for quality control and certification of water flowing through DUWLs, including the absence of NTM. Our report also shows the need for a rapid recognition of NTM infections and accurate laboratory diagnosis in order to avoid long-term ineffective antibiotic treatment.

Efficacy of BRS® and Alpron®/Bilpron® Disinfectants for Dental Unit Waterlines: A Six-Year Study

Biofilms in dental unit waterlines (DUWL) are a potentially significant source of contamination posing a significant health risk as these may come into contact with patients and dental staff during treatment. The aim of this study was to evaluate the microbiological quality of DUWL water treated by Biofilm-Removing-System^® (BRS^®) and Alpron^®/Bilpron^® disinfectant solutions for six years in a French university hospital. The microbiological quality of water supplied by 68 dental units—initially shock treated with BRS^®, then continuously treated by Alpron^® with sterile water during working days and Bilpron^® during inactivity period, and combined with purging every morning and after each patient—was assessed biannually during six years for total culturable aerobic bacteria at 22 °C and 36 °C, Legionella sp., Pseudomonas aeruginosa, and total coliforms. A total of 628 samples were analyzed, 99.8% were compliant with extended microbiological levels, and we never detected pathogen bacteria like Legionella sp. and P. aeruginosa. Only one sample (0.2%) was noncompliant with the level of total culturable aerobic bacteria at 36 °C, which exceeded 140 colony forming units per mL. The protocol implemented in our university hospital gives excellent results and enables control of the microbiological quality of DUWL water in the long term.

Pediatric Mandible Reconstruction for Osteomyelitis During Largest Reported Mycobacterium Abscessus Outbreak

In 2016, water lines at a children's dental clinic in Orange County, California were contaminated with Mycobacterium abscessus (MA), a non-tuberculosis rapidly-growing mycobacterium, leading to the largest MA outbreak ever reported. Mandatory reporting and active case finding directed by the Public Health Department was conducted in collaboration with community Pediatric Infectious Disease physicians for patients who underwent dental pulpotomies at the contaminated Dental Clinic from January 1 to September 6, 2016. Seventy-one cases (22 confirmed and 49 probable) were identified. One case that required extensive debridement and reconstruction of the mandible is presented in detail. CT maxillofacial demonstrated osteomyelitis extending from the right mandibular angle to the left ramus with multifocal periapical lucencies. CT chest and neck revealed numerous pulmonary nodules and bilateral cervical lymphadenopathy. Extraction of several involved teeth, bilateral selective neck dissection, and extensive mandibular debridement was performed, followed by mandibular stabilization with a custom pre-bent 2.0-mm locking plate. CT images 1-year post-operative showed clearance of infection and sufficient bony stability. Subsequent removal of hardware and bone grafting was performed and the patient is doing well. In the event of a future odontogenic mycobacterium outbreak, the experience at our institution can inform multidisciplinary treatment approaches. Prophylactic extraction of primary teeth that received pulpotomies with contaminated water should be performed. Early and thorough debridement of affected bone, including enucleation of secondary teeth, should be performed if necessary for early source control.

Dental Unit Waterlines: A Survey of Practices in Eastern France

Water is essential during dental care. Physical and chemical techniques should be used to maintain a good water quality with respect to bacteria, and to ensure the safety of exposed patients and dental staff. The aim of this survey was to assess the modalities used by dental practitioners in Eastern France to maintain the water quality of their dental unit waterlines (DUWLs). A questionnaire about water quality maintenance practices was sent to 870 dental offices in 2016. The questionnaires were completed by 153 dental offices, covering about 223 dental care units. The majority of units were fed by mains water (91.0%), which is generally unfiltered (71.3%). One-third (33.6%) of the units had an independent water bottle reservoir. Flushing, a basic physical technique to improve the quality of units’ outflow water, was practiced in 65.4% of dental offices. Concerning the chemical treatment of water, it was used for 62.1% of the units. An analysis of the microbiological quality of the DUWL water was only carried out in 2.6% of the offices. In conclusion, providing better training to dental staff seems necessary to improve their practices and to generalize procedures that improve the microbiological quality of the water used.

Investigation of healthcare infection risks from water-related organisms: Summary of CDC consultations, 2014-2017

OBJECTIVE

Water exposures in healthcare settings and during healthcare delivery can place patients at risk for infection with water-related organisms and can potentially lead to outbreaks. We aimed to describe Centers for Disease Control and Prevention (CDC) consultations involving water-related organisms leading to healthcare-associated infections (HAIs).

DESIGN

Retrospective observational study.

METHODS

We reviewed internal CDC records from January 1, 2014, through December 31, 2017, using water-related terms and organisms, excluding Legionella, to identify consultations that involved potential or confirmed transmission of water-related organisms in healthcare. We determined plausible exposure pathways and routes of transmission when possible.

RESULTS

Of 620 consultations during the study period, we identified 134 consultations (21.6%), with 1,380 patients, that involved the investigation of potential water-related HAIs or infection control lapses with the potential for water-related HAIs. Nontuberculous mycobacteria were involved in the greatest number of investigations (n = 40, 29.9%). Most frequently, investigations involved medical products (n = 48, 35.8%), and most of these products were medical devices (n = 40, 83.3%). We identified a variety of plausible water-exposure pathways, including medication preparation near water splash zones and water contamination at the manufacturing sites of medications and medical devices.

CONCLUSIONS

Water-related investigations represent a substantial proportion of CDC HAI consultations and likely represent only a fraction of all water-related HAI investigations and outbreaks occurring in US healthcare facilities. Water-related HAI investigations should consider all potential pathways of water exposure. Finally, healthcare facilities should develop and implement water management programs to limit the growth and spread of water-related organisms.

Cross-transmission in the Dental Office: Does This Make You Ill?

PURPOSE OF REVIEW

Recently, numerous scientific publications were published which shed new light on the possible risks of infection for dental healthcare workers and their patients. This review aimed to provide the latest insights in the relative risks of transmission of (pathogenic) micro-organisms in the dental office.

RECENT FINDINGS

Of all different routes of micro-organism transmission during or immediately after dental treatment (via direct contact/via blood-blood contact/via dental unit water and aerosols), evidence of transmission is available. However, the recent results put the risks in perspective; infections related to the dental office are most likely when infection control measures are not followed meticulously.

SUMMARY

The risk for transmission of pathogens in a dental office resulting in an infectious disease is still unknown; it seems to be limited in developed countries but it cannot be considered negligible. Therefore, maintaining high standards of infection preventive measures is of high importance for dental healthcare workers to avoid infectious diseases due to cross-contamination.

Mycobacterium abscessus Infections in Children: A Review of Current Literature

There is limited literature on Mycobacterium abscessus infections in children and limited data about its diagnosis and management. The incidence of infections due to M abscessus appears to be increasing in certain populations and can be a significant cause of morbidity and mortality.Management of these infections is challenging and relies on combination antimicrobial therapy and debridement of diseased tissue, depending on the site and extent of disease. Treatment regimens often are difficult to tolerate, and the antimicrobials used can cause significant adverse effects, particularly given the long duration of therapy needed.This review summarizes the literature and includes information from our own institution's experience on pediatric M abscessus infections including the epidemiology, transmission, clinical manifestations, and the management of these infections. Adult data have been used where there are limited pediatric data. Further studies regarding epidemiology and risk factors, clinical presentation, optimal treatment, and outcomes in children are necessary.

Extrapulmonary Nontuberculous Mycobacterial Disease Surveillance - Oregon, 2014-2016

Nontuberculous mycobacteria (NTM), ubiquitous in soil and water, usually infect immunocompromised persons. However, even healthy persons are susceptible to infection through percutaneous inoculation. Although 77% of NTM diseases manifest as primarily pulmonary illnesses (1), NTM also infect skin, bones, joints, the lymphatic system, and soft tissue. NTM infections can have incubation periods that exceed 5 years (2), often require prolonged treatment, and can lead to sepsis and death. Extrapulmonary NTM outbreaks have been reported in association with contaminated surgical gentian violet (3), nail salon pedicures (4), and tattoos received at tattoo parlors (5), although few surveillance data have been available for estimating the public health burden of NTM.* On January 1, 2014, the Oregon Health Authority designated extrapulmonary NTM disease a reportable condition. To characterize extrapulmonary NTM infection, estimate resources required for surveillance, and assess the usefulness of surveillance in outbreak detection and investigation, 2014–2016 extrapulmonary NTM surveillance data were reviewed, and interviews with stakeholders were conducted. During 2014–2016, 134 extrapulmonary NTM cases (11 per 1 million persons per year) were reported in Oregon. The age distribution was bimodal, with highest incidence among persons aged <10 years (20 per 1 million persons per year) and persons aged 60–69 years (18 per 1 million persons per year). The most frequently reported predisposing factors (occurring within 14–70 days of symptom onset) were soil exposure (41/98; 42%), immunocompromised condition (42/124; 34%), and surgery (32/120; 27%). Overall, 43 (33%) patients were hospitalized, 18 (15%) developed sepsis, and one (0.7%) died. Surveillance detected or helped to control two outbreaks at low cost. Jurisdictions interested in implementing extrapulmonary NTM surveillance can use the Council of State and Territorial Epidemiologists (CSTE) standardized case definition (6) for extrapulmonary NTM reporting or investigative guidelines maintained by the Oregon Health Authority (7).

Diagnosis and Management of Children With Mycobacterium abscessus Infections in the Head and Neck

PURPOSE

Controversy exists regarding the most appropriate treatment strategy for children with nontuberculous mycobacterial (NTM) cervical lymphadenitis. Mycobacterium abscessus (MAB) is an uncommon cause of NTM cervical lymphadenitis. The purpose of the present study was to evaluate diagnosis, management, and treatment outcomes in children with MAB-associated cervical lymphadenitis resulting from a pulpotomy.

MATERIALS AND METHODS

This was a retrospective chart review of children with NTM lymphadenitis of the head and neck caused by MAB treated at Children's Healthcare of Atlanta hospitals (Atlanta, GA). The predictor variables were patient demographics, dental history, clinical presentation, imaging characteristics, laboratory findings, histopathologic examination, treatment, and complications. The outcome variable was disease resolution or persistence.

RESULTS

Twenty-two patients (mean age, 6.5 yr) met the inclusion criteria. All patients had pulpotomy at 1 dental practice. The mean time from dental procedure to symptom onset was 43.1 days (range, 3 to 180 days). Children presented with cervical or submandibular swelling, facial swelling, gingival erythema, and skin erythema. Radiographic findings were submandibular or cervical lymphadenitis, maxillary or mandibular osteolysis, subcutaneous abscess, and pulmonary nodules. All children had confirmed or probable MAB infection diagnosed on the pathologic specimen. There were 2 distinct patient presentations that guided surgical management: isolated noninflammatory cervical lymphadenitis, which was partly or completely excised (n = 11), and adjacent extension or disseminated infection requiring subtotal lymph node excision, bone debridement, and postoperative antibiotics (n = 11). Most children required multiple surgical interventions to remove infected tissues. All achieved clinical resolution.

CONCLUSION

In this cohort, treatment of NTM lymphadenitis caused by MAB depended on extent of disease and virulence of bacteria. When complete surgical excision was possible, disease resolution was achieved. However, in cases with adjacent extension or dissemination infection, postoperative antibiotics were necessary.

Recomendaciones para prevenir la transmisión de Mycobacterium abscessus en los procedimientos odontológicos

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Diagnostics and laboratory role in outbreaks

PURPOSE OF REVIEW

The review describes the investigative benefits of traditional and novel molecular epidemiology techniques, while acknowledging the limitations faced by clinical laboratories seeking to implement these methods.

RECENT FINDINGS

Pulse-field gel electrophoresis and other traditional techniques remain powerful tools in outbreak investigations and continue to be used by multiple groups. Newer techniques such as matrix-assisted laser desorption/ionization-time of flight mass-spectrometry and whole genome sequencing show great promise. However, there is a lack of standardization regarding definitions for genetic relatedness, nor are there established criteria for accuracy and reproducibility. There are also challenges regarding availability of trained bioinformatics staff, and concerns regarding reimbursement.

SUMMARY

There are many tools available for molecular epidemiologic investigation. Epidemiologists and clinical laboratorians should work together to determine which testing methods are best for each institution.

Outbreaks of nontuberculous mycobacteria

PURPOSE OF REVIEW

The purpose of this review is to summarize the emerging literature on nontuberculous mycobacteria outbreaks in healthcare settings. As our ability to identify mycobacterial species develops, we are better able to recognize epidemiologic connections and better understand the prevalence and importance of these outbreaks and pseudo-outbreaks in healthcare settings.

RECENT FINDINGS

The number of outbreaks related to nontuberculous outbreaks is increasing because of heightened awareness and better diagnostic tests for species level identification of mycobacteria. Outbreaks in healthcare settings have been related to cardiac surgery, plastic surgery, including medical tourism, colonized humidifiers and heater-cooler devices, imperfect disinfection, and hospital water sources. Mycobacteria have a predilection to form biofilms, are resistant to disinfection and are prevalent in hospital water systems. Patients with structural lung disease like cystic fibrosis patients are at particularly high risk for mycobacterial infection. It has been thought that acquisition in this patient population is from common environmental exposure; however, there is increasing evidence that transmission in this patient population can occur through either direct or indirect patient-to-patient spread.

SUMMARY

Mycobacteria outbreaks in healthcare settings have been underrecognized. As we identify additional clusters of infection with better diagnostic tools and heightened awareness, we will likely need better infection control practices to prevent infections in healthcare settings.

Pediatric Dental Clinic-Associated Outbreak of Mycobacterium abscessus Infection

BACKGROUND

Mycobacterium abscessus is an uncommon cause of invasive odontogenic infection.

METHODS

M abscessus-associated odontogenic infections occurred in a group of children after they each underwent a pulpotomy. A probable case-child was defined as a child with facial or neck swelling and biopsy-confirmed granulomatous inflammation after a pulpotomy between October 1, 2013, and September 30, 2015. M abscessus was isolated by culture in confirmed case-children. Clinical presentation, management, and outcomes were determined by medical record abstraction.

RESULTS

Among 24 children, 14 (58%) were confirmed case-children. Their median age was 7.3 years (interquartile range, 5.8-8.2 years), and the median time from pulpotomy to symptom onset was 74 days (range, 14-262 days). Clinical diagnoses included cervical lymphadenitis (24 [100%] of 24), mandibular or maxillary osteomyelitis (11 [48%] of 23), and pulmonary nodules (7 [37%] of 19). Each child had ≥1 hospitalization and a median of 2 surgeries (range, 1-6). Of the 24 children, 12 (50%) had surgery alone and 11 (46%) received intravenous (IV) antibiotics. Nineteen of the 24 (79%) children experienced complications, including vascular access malfunction (7 [64%] of 11), high-frequency hearing loss (5 [56%] of 9), permanent tooth loss (11 [48%] of 23), facial nerve palsy (7 [29%] of 24), urticarial rash (3 [25%] of 12), elevated liver enzyme levels (1 [20%] of 5), acute kidney injury (2 [18%] of 11), incision dehiscence/fibrosis (3 [13%] of 24), and neutropenia (1 [9%] of 11).

CONCLUSIONS

M abscessus infection was associated with significant medical morbidity and treatment complications. Unique manifestations included extranodal mandibular or maxillary osteomyelitis and pulmonary nodules. Challenges in the identification of case-children resulted from an extended incubation period and various clinical manifestations. Clinicians should consider the association between M abscessus infection and pulpotomy in children who present with subacute cervical lymphadenitis. The use of treated/sterile water during pulpotomy might prevent further outbreaks.

Rapidly Growing Mycobacteria

Rapidly growing mycobacteria (RGM) compose approximately one-half of the currently validated mycobacterial species and are divided into six major groups, including the Mycobacterium fortuitum group, M. chelonae/M. abscessus complex, M. smegmatis group, M. mucogenicum group, M. mageritense / M. wolinskyi , and the pigmented RGM. This review discusses each group and highlights the major types of infections associated with each group. Additionally, phenotypic and molecular laboratory identification methods, including gene sequencing, mass spectrometry, and the newly emerging whole-genome sequencing, are detailed, along with a discussion of the current antimicrobial susceptibility methods and patterns of the most common pathogenic species.

Medical Management for the Treatment of Nontuberculous Mycobacteria Infection of the Parotid Gland: Avoiding Surgery May Be Possible

Infection with nontuberculous mycobacteria (NTM) is uncommon in the head and neck; therefore there is no clear consensus on treating these infections. Our objective was to report our experience with a unique case of NTM infection of the parotid in an immunocompetent patient, in order to determine appropriate management through our experience with this pathology. A 57-year-old man, known for numerous comorbid diseases, presented to our institution complaining of right parotid swelling and pain. A computed tomography (CT) of the neck showed a multiloculated collection in the inferior portion of the right parotid gland, compatible with abscess formation. This abscess was drained by interventional radiology (IR) but required repeat drainage twice due to lack of initial improvement. He was treated with several antibiotics as culture results initially indicated Gram-positive bacilli and then Mycobacterium species, with final identification by a reference laboratory as Mycobacterium abscessus. Imipenem was initiated with amikacin and clarithromycin. His infection clinically and radiologically resolved after 5 months of antibiotherapy. In our case, the patient improved following intravenous antibiotic therapy. Our experience demonstrates that appropriate antibiotherapy can lead to resolution of Mycobacterium abscessus infection in the parotid without the risks associated with surgical intervention.