In studies, the automated microbial susceptibility testing device for smartphone performed with 98.2% accuracy, meeting FDA criteria
Imagine doing antimicrobial susceptibility testing outside a clinical laboratory. That’s the goal of researchers on the West Coast who are developing a smartphone-based diagnostic device with the capability of performing this type of point-of-care testing (POCT).
This new mobile POCT device is under development at the University of California-Los Angeles (UCLA). It promises to bring antimicrobial susceptibility testing—a routine procedure in the most medical laboratories—to remote, resource-limited areas of the world.
Further development of this novel technology could result in new, more sensitive assays for clinical laboratories to use in the effort to improve antimicrobial stewardship in hospitals
Researchers at McMaster University in Ontario, Canada, have used artificial intelligence (AI) to identify a potential antibiotic that neutralizes the drug-resistant bacteria Acinetobacter baumannii, an antibiotic resistant pathogen commonly found in many hospitals. This will be of interest to clinical laboratory managers and microbiologists involved in identifying strains of bacteria to determine if they are antimicrobial-resistant (AMR) superbugs.
Using machine learning, the scientists screened thousands molecules to look for those that inhibited the growth of this specific pathogen. And they succeeded.
“We trained a neural network with this growth inhibition dataset and performed in silico predictions for structurally new molecules with activity against A. baumannii,” the researchers wrote in their published study.
They discovered that the molecule abaucin inhibited the growth of the antibiotic-resistant pathogen in vitro.
This shows how machine learning and AI technologies are giving biomedical researchers tools to identify new therapeutic drugs that are effective against drug-resistant strains of bacteria. This same research can be expected to lead to new clinical laboratory assays that determine if superbugs can be attacked by specific therapeutic drugs.
“When I think about AI in general, I think of these models as things that are just going to help us do the thing we’re going to do better,” Jonathan Stokes, PhD, Assistant Professor of Biomedicine and Biochemistry at McMaster University in Ontario, Canada, and lead author of the study, told USA Today. Clinical laboratory scientists and microbiologists will be encouraged by the McMaster University scientists’ findings. (Photo copyright: McMaster University.)
McMaster Study Details
Jonathan Stokes, PhD, head of the Stokes Laboratory at McMaster University, is Assistant Professor of Biomedicine/Biochemistry at McMaster and lead author of the study. Stokes’ team worked with researchers from the Broad Institute of MIT and Harvard to explore the effectiveness of AI in combating superbugs, USA Today reported.
“This work highlights the utility of machine learning in antibiotic discovery and describes a promising lead with targeted activity against a challenging Gram-negative pathogen,” the researchers wrote in Nature Chemical Biology.
Stokes Lab utilized the high-throughput drug screening technique, spending weeks growing and exposing Acinetobacter baumannii to more than 7,500 agents of drugs and active ingredients of drugs. When 480 compounds were uncovered that blocked the growth of bacteria, this information was then provided to a computer that was trained to run an AI algorithm, CNN reported.
“Once we had our [machine learning] model trained, what we could do then is start showing that model brand-new pictures of chemicals that it had never seen, right? And based on what it had learned during training, it would predict for us whether those molecules were antibacterial or not,” Stokes told CNN.
The model spent hours screening more than 6,000 molecules. It then narrowed the search to 240 chemicals, which were tested in the lab. The scientists pared down the results to the nine most effective inhibitors of bacteria. They then eliminated those that were either related to existing antibiotics or might be considered dangerous.
The researchers found one compound—RS102895 (abaucin)—which, according to Stokes, was likely created to treat diabetes, CNN reported. The scientists discovered that the compound prevented bacterial components from making their way from inside a cell to the cell’s surface.
“It’s a rather interesting mechanism and one that is not observed amongst clinical antibiotics so far as I know,” Stokes told CNN.
Because of the effectiveness of the antibiotic during testing on mice skin, the researchers believe this method may be useful for creating antibiotics custom made to battle additional drug resistant pathogens, CNN noted.
Defeating a ‘Professional Pathogen’
Acinetobacter baumannii (A. baumannii)—the focus of Stoke’s study—is often found on hospital counters and doorknobs and has a sneaky way of using other organisms’ DNA to resist antibiotic treatment, according to CNN.
“It’s what we call in the laboratory a professional pathogen,” Stokes told CNN.
A. baumannii causes infections in the urinary tract, lungs, and blood and typically wreaks havoc to vulnerable patients on breathing machines, in intensive care units, or undergoing surgery, USA Today reported.
A. baumannii is resistant to carbapenem, a potent antibiotic. The Centers for Disease Control and Prevention (CDC) reported that in 2017 the bacteria infected 8,500 people in hospitals, 700 of those infections being fatal.
Further, in its 2019 “Antibiotic Resistance Threats in the United States” report, the CDC stated that one out of every four patients infected with the bacteria died within one month of their diagnosis. The federal agency deemed the bacteria “of greatest need” for new antibiotics.
Thus, finding a way to defeat this particularly nasty bacteria could save many lives.
Implications of Study Findings on Development of new Antibiotics
The Stokes Laboratory study findings show promise. If more antibiotics worked so precisely, it’s possible bacteria would not have a chance to become resistant in the first place, CNN reported.
Next steps in Stokes’ research include optimizing the chemical structure and testing in larger animals or humans, USA Today reported.
“It’s important to remember [that] when we’re trying to develop a drug, it doesn’t just have to kill the bacterium,” Stokes noted. “It also has to be well tolerated in humans and it has to get to the infection site and stay at the infection site long enough to elicit an effect,” USA Today reported.
Stokes’ study is a prime example of how AI can make a big impact in clinical laboratory diagnostics and treatment.
“We know broad-spectrum antibiotics are suboptimal and that pathogens have the ability to evolve and adjust to every trick we throw at them … AI methods afford us the opportunity to vastly increase the rate at which we discover new antibiotics, and we can do it at a reduced cost. This is an important avenue of exploration for new antibiotic drugs,” Stokes told CNN.
Clinical laboratory managers and microbiologists may want to keep an open-mind about the use of AI in drug development. More research is needed to give substance to the McMaster University study’s findings. But the positive results may lead to methods for fine tuning existing antibiotics to better combat antimicrobial-resistant bacteria, USA Today reported.
The UE study sheds light on the types of bacteria in
wastewater that goes down hospital pipes to sewage treatment plants. The study
also revealed that not all infectious agents are killed after passing through
waste treatment plants. Some bacteria with antimicrobial (or antibiotic)
resistance survive to enter local food sources.
The scientists concluded that the amount of AMR genes found
in hospital wastewater was linked to patients’ length-of-stays and consumption
of antimicrobial resistant bacteria while in the hospital.
In a paper the University of Edinburgh published on medRxiv, the researchers wrote: “There was a higher abundance of antimicrobial-resistance genes in the hospital wastewater samples when compared to Seafield community sewage works … Sewage treatment does not completely eradicate antimicrobial-resistance genes and thus antimicrobial-resistance genes can enter the food chain through water and the use of [processed] sewage sludge in agriculture. As hospital wastewater contains inpatient bodily waste, we hypothesized that it could be used as a representation of inpatient community carriage of antimicrobial resistance and as such may be a useful surveillance tool.”
Additionally, they wrote, “Using metagenomics to identify
the full range of AMR genes in hospital wastewater could represent a useful
surveillance tool to monitor hospital AMR gene outflow and guide environmental
policy on AMR.”
Antimicrobial stewardship programs are becoming increasingly critical to preventing the spread of AMR bacteria. “By having those programs, [there are] documented cases of decreased antibiotic resistance within organisms causing these infections,” Paul Fey, PhD, of the University of Nebraska Medical Center, told MedPage Today. “This is another indicator of how all hospitals need to implement stewardship programs to have a good handle on decreasing antibiotic use.” [Photo copyright: University of Nebraska.]
Don’t Waste the Wastewater
Antibiotic resistance occurs when bacteria change in response to medications to prevent and treat bacterial infections, according to a World Health Organization (WHO) fact sheet. The CDC estimates that more than 23,000 people die annually from two million antibiotic-resistance infections.
Wastewater, the UE scientists suggest, should not go to
waste. It could be leveraged to improve hospitals’ detection of patients with antimicrobial
resistance, as well as to boost environment antimicrobial-resistance polices.
They used metagenomics (the study of genetic material
relative to environmental samples) to compare the antimicrobial-resistance
genes in hospital wastewater against wastewater from community sewage
points.
The UE researchers:
First collected samples over a 24-hour period from various areas in a tertiary hospital;
They then obtained community sewage samples from various locations around Seafield, Scotland;
Antimicrobial-resistance genes increased with longer length of patient stays, which “likely reflects transmission amongst hospital inpatients,” researchers noted.
Fey suggests that further research into using sequencing
technology to monitor patients is warranted.
“I think that monitoring each patient and sequencing their
bowel flora is more likely where we’ll be able to see if there’s a significant
carriage of antibiotic-resistant organisms,” Fey told MedPage Today. “In
five years or so, sequencing could become so cheap that we could monitor every
patient like that.”
Fey was not involved in the University of Edinburgh
research.
Given the rate at which AMR bacteria spreads, finding antibiotic-resistance
genes in hospital wastewater may not be all that surprising. Still, the University
of Edinburgh study could lead to cost-effective ways to test the genes of
bacteria, which then could enable researchers to explore different sources of
infection and determine how bacteria move through the environment.
And, perhaps most important, the study suggests clinical
laboratories have many opportunities to help eliminate infections and slow
antibiotic resistance. Microbiologists can help move their organizations forward
too, along with infection control colleagues.
Contrary to CMS and Joint Commission programs implemented in 2017 to reduce them, incidents of hospital-acquired infections have risen for the past few years
Nevertheless, a recent Leapfrog Group report indicates hospitals are finding it increasingly difficult to remove infections all together. This has many healthcare leaders concerned.
The report, which was analyzed by Castlight Health, states that the number of hospitals reporting zero infections has declined significantly since 2015, according to a news release. According to the Leapfrog Group’s report:
Two million people acquire HAIs every year;
90,000 people die annually from HAIs;
HAI costs range from $1,000 to $50,000 depending on the infection.
Hospitals spend $28 to $45 billion annually on HAI costs, Healthcare Finance reported.
“I think it’s far too easy to let something slip, so it’s clear that there really needs to be a renewed focus on getting back to zero. We do still see some hospitals that are getting to zero, so it’s clearly possible,” Erica Mobley (above), Leapfrog Group’s Director of Operations, told Fierce Healthcare. (Photo copyright: LinkedIn.)
Regressing Instead of Progressing Toward Total HAI Elimination
Leapfrog Group’s report is based on 2017 hospital survey data submitted by 2,000 providers. The data indicates that in just two years the number of hospitals reporting zero HAIs dropped by up to 50%. The reported HAIs include:
Central line-associated bloodstream infections (CLABSI) occurring in Intensive Care and other units: 12.7% of hospitals reporting zero CLABSI infections in 2017, down from 25% in 2015;
The remaining infection measures studied by Leapfrog Group had less dramatic decreases over the same time period, according to Fierce Healthcare. Nevertheless, they are significant. They include:
Surgical site infections (SSI) following colon surgery: 19% zero infections compared to 23% previously;
Clostridium difficile (C. difficile) inpatient infections: 3% zero inpatient infections in 2017, compared to 5% in 2015.
Joint Commission Studies Antimicrobial Program Progress
Hospitals have revised their antimicrobial programs, which originally operated on a “top-down” structure, to programs that include clinicians from throughout entire provider organizations;
Health information technology (HIT) can enable real-time opportunities to launch antimicrobial therapy and treat patients; and,
Some barriers exist in getting resources to integrate technology and analyze data.
“These programs used expansion of personnel to amplify the antimicrobial stewardship programs’ impact and integrated IT resources into daily workflow to improve efficiency,” the researchers wrote. “Hospital antimicrobial stewardship programs can reduce inappropriate antimicrobial use, length of stay, C. difficile infection, rates of resistant infections, and cost.”
What Do CMS and Joint Commission Expect?
According to Contagion, while the Joint Commission program is part of medication management, CMS places its requirements for the antimicrobial stewardship program under “infection prevention.”
CMS requirements for an antimicrobial stewardship program include:
Developing antimicrobial stewardship program policies and procedures;
Implementing hospital-wide efforts;
Involving antimicrobial stakeholders for focus on antimicrobial use and bacterial resistance;
Setting evidence-based antimicrobial use goals; and,
Reducing effects of antimicrobial use in areas of C. difficile infections and antibiotic resistance.
Leapfrog Group’s data about fewer hospitals reporting zero infections offers opportunities for hospital laboratory microbiology professionals to get involved with hospital-wide antimicrobial program teams and processes and help their hospitals progress back to zero HAIs. Clinical laboratories, both hospital-based and independent, also have opportunities to contribute to improving the antimicrobial stewardship efforts of the physicians who refer them specimens.
Genomic analysis of pipes and sewers leading from the National Institutes of Health Clinical Care Center in Bethesda, Md., reveals the presence of carbapenem-resistant organisms; raises concern about the presence of multi-drug-resistant bacteria previously undetected in hospital settings
If hospitals and medical laboratories are battlegrounds, then microbiologists and clinical laboratory professionals are frontline soldiers in the ongoing fight against hospital-acquired infections (HAIs) and antibiotic resistance. These warriors, armed with advanced testing and diagnostic skills, bring expertise to antimicrobial stewardship programs that help block the spread of infectious disease. In this war, however, microbiologists and medical laboratory scientists (AKA, medical technologists) also often discover and identify new and potential strains of antibiotic resistance.
Potential Source of Superbugs and Hospital-Acquired Infections
According to the mBio study, “Carbapenemase-producing organisms (CPOs) are a global concern because of the morbidity and mortality associated with these resistant Gram-negative bacteria. Horizontal plasmid transfer spreads the resistance mechanism to new bacteria, and understanding the plasmid ecology of the hospital environment can assist in the design of control strategies to prevent nosocomial infections.”
Karen Frank, MD, PhD (above), is Chief of the Microbiology Service Department at the National Institutes of Health and past-president of the Academy of Clinical Laboratory Physicians and Scientists. She suggests hospitals begin tracking the spread of the bacteria. “In the big picture, the concern is the spread of these resistant organisms worldwide, and some regions of the world are not tracking the spread of the hospital isolates.” (Photo copyright: National Institutes of Health.)
Frank’s team used Illumina’s MiSeq next-generation sequencer and single-molecule real-time (SMRT) sequencing paired with genome libraries, genomics viewers, and software to analyze the genomic DNA of more than 700 samples from the plumbing and sewers. They discovered a “potential environmental reservoir of mobile elements that may contribute to the spread of resistance genes, and increase the risk of antibiotic resistant ‘superbugs’ and difficult to treat hospital-acquired infections (HAIs).”
Genomic Sequencing Identifies Silent Threat Lurking in Sewers
Frank’s study was motivated by a 2011 outbreak of antibiotic-resistant Klebsiella pneumoniae bacteria that spread through the NIHCC via plumbing in ICU, ultimately resulting in the deaths of 11 patients. Although the hospital, like many others, had dedicated teams working to reduce environmental spread of infectious materials, overlooked sinks and pipes were eventually determined to be a disease vector.
In an NBC News report on Frank’s study, Amy Mathers, MD, Director of The Sink Lab at the University of Virginia, noted that sinks are often a locus of infection. In a study published in Applied and Environmental Microbiology, another journal of the ASM, Mathers noted that bacteria in drains form a difficult to clean biofilm that spreads to neighboring sinks through pipes. Mathers told NBC News that despite cleaning, “bacteria stayed adherent to the wall of the pipe” and even “splashed out” into the rooms with sink use.
During the 2011-2012 outbreak, David Henderson, MD, Deputy Director for Clinical Care at the NIHCC, told the LA Times of the increased need for surveillance, and predicted that clinical laboratory methods like genome sequencing “will become a critical tool for epidemiology in the future.”
Frank’s research fulfilled Henderson’s prediction and proved the importance of genomic sequencing and analysis in tracking new potential sources of infection. Frank’s team used the latest tools in genomic sequencing to identify and profile microbes found in locations ranging from internal plumbing and floor drains to sink traps and even external manhole covers outside the hospital proper. It is through that analysis that they identified the vast collection of CPOs thriving in hospital wastewater.
In an article, GenomeWeb quoted Frank’s study, noting that “Over two dozen carbapenemase gene-containing plasmids were identified in the samples considered” and CPOs turned up in nearly all 700 surveillance samples, including “all seven of the wastewater samples taken from the hospital’s intensive care unit pipes.” Although the hospital environment, including “high-touch surfaces,” remained free of similar CPOs, Frank’s team noted potential associations between patient and environmental isolates. GenomeWeb noted Frank’s findings that CPO levels were in “contrast to the low positivity rate in both the patient population and the patient-accessible environment” at NIHCC, but still held the potential for transmission to vulnerable patients.
Since carbapenems are a “last resort” antibiotic for bacteria resistant to other antibiotics, the NIHCC “reservoir” of CPOs is a frightening discovery for physicians, clinical laboratory professionals, and the patients they serve.
The high CPO environment in NIHCC wastewater has the capability to spread resistance to bacteria even without the formal introduction of antibiotics. In an interview with Healthcare Finance News, Frank indicated that lateral gene transfer via plasmids was not only possible, but likely.
“The bacteria fight with each other and plasmids can carry genes that help them survive. As part of a complex bacterial community, they can transfer the plasmids carrying resistance genes to each other,” she noted. “That lateral gene transfer means bacteria can gain resistance, even without exposure to the antibiotics.”
The discovery of this new potential “reservoir” of CPOs may mean new focused genomic work for microbiologists and clinical laboratories. The knowledge gained by the discovery of CPOs in hospital waste water and sinks offers a new target for study and research that, as Frank concludes, will “benefit healthcare facilities worldwide” and “broaden our understanding of antimicrobial resistance genes in multi-drug resistant (MDR) bacteria in the environment and hospital settings.”
