Study results from Switzerland come as clinical laboratory scientists seek new ways to tackle the problem of antimicrobial resistance in hospitals
Microbiologists and clinical laboratory scientists engaged in the fight against antibiotic-resistant (aka, antimicrobial resistant) bacteria will be interested in a recent study conducted at the University of Basel and University Hospital Basel in Switzerland. The epidemiologists involved in the study discovered that some of these so-called “superbugs” can remain in the body for as long as nine years continuing to infect the host and others.
The researchers wanted to see how two species of drug-resistant bacteria—K. pneumoniae and E. coli—changed over time in the body, according to a press release from the university. They analyzed samples of the bacteria collected from patients who were admitted to the hospital over a 10-year period, focusing on older individuals with pre-existing conditions. They found that K. pneumoniae persisted for up to 4.5 years (1,704 days) and E. coli persisted for up to nine years (3,376 days).
“These patients not only repeatedly become ill themselves, but they also act as a source of infection for other people—a reservoir for these pathogens,” said Lisandra Aguilar-Bultet, PhD, the study’s lead author, in the press release.
“This is crucial information for choosing a treatment,” explained Sarah Tschudin Sutter, MD, Head of the Division of Infectious Diseases and Hospital Epidemiology, and of the Division of Hospital Epidemiology, who specializes in hospital-acquired infections and drug-resistant pathogens. Sutter led the Basel University study.
“The issue is that when patients have infections with these drug-resistant bacteria, they can still carry that organism in or on their bodies even after treatment,” said epidemiologist Maroya Spalding Walters, MD (above), who leads the Antimicrobial Resistance Team in the Division of Healthcare Quality Promotion at the federal Centers for Disease Control and Prevention (CDC). “They don’t show any signs or symptoms of illness, but they can get infections again, and they can also transmit the bacteria to other people.” Clinical laboratories working with microbiologists on antibiotic resistance will want to follow the research conducted into these deadly pathogens. (Photo copyright: Centers for Disease Control and Prevention.)
COVID-19 Pandemic Increased Antibiotic Resistance
The Basel researchers looked at 76 K. pneumoniae isolates recovered from 19 patients and 284 E. coli isolates taken from 61 patients, all between 2008 and 2018. The study was limited to patients in which the bacterial strains were detected from at least two consecutive screenings on admission to the hospital.
“DNA analysis indicates that the bacteria initially adapt quite quickly to the conditions in the colonized parts of the body, but undergo few genetic changes thereafter,” the Basel University press release states.
The researchers also discovered that some of the samples, including those from different species, had identical mechanisms of drug resistance, suggesting that the bacteria transmitted mobile genetic elements such as plasmids to each other.
One limitation of the study, the authors acknowledged, was that they could not assess the patients’ exposure to antibiotics.
Meanwhile, recent data from the World Health Organization (WHO) suggests that the COVID-19 pandemic might have exacerbated the challenges of antibiotic resistance. Even though COVID-19 is a viral infection, WHO scientists found that high percentages of patients hospitalized with the disease between 2020 and 2023 received antibiotics.
“While only 8% of hospitalized patients with COVID-19 had bacterial co-infections requiring antibiotics, three out of four or some 75% of patients have been treated with antibiotics ‘just in case’ they help,” the WHO stated in a press release.
WHO uses an antibiotic categorization system known as AWaRe (Access, Watch, Reserve) to classify antibiotics based on risk of resistance. The most frequently prescribed antibiotics were in the “Watch” group, indicating that they are “more prone to be a target of antibiotic resistance and thus prioritized as targets of stewardship programs and monitoring.”
“When a patient requires antibiotics, the benefits often outweigh the risks associated with side effects or antibiotic resistance,” said Silvia Bertagnolio, MD, Unit Head in the Antimicrobial resistance (AMR) Division at the WHO in the press release. “However, when they are unnecessary, they offer no benefit while posing risks, and their use contributes to the emergence and spread of antimicrobial resistance.”
Citing research from the National Institutes of Health (NIH), NPR reported that in the US, hospital-acquired antibiotic-resistant infections increased 32% during the pandemic compared with data from just before the outbreak.
“While that number has dropped, it still hasn’t returned to pre-pandemic levels,” NPR noted.
The UPenn researchers have already developed an antimicrobial treatment derived from guava plants that has proved effective in mice, Vox reported. They’ve also trained an AI model to scan the proteomes of extinct organisms.
“The AI identified peptides from the woolly mammoth and the ancient sea cow, among other ancient animals, as promising candidates,” Vox noted. These, too, showed antimicrobial properties in tests on mice.
These findings can be used by clinical laboratories and microbiologists in their work with hospital infection control teams to better identify patients with antibiotic resistant strains of bacteria who, after discharge, may show up at the hospital months or years later.
Device could pave the way for real-time, noninvasive breath analysis to detect and monitor diseases and be a new service medical laboratories can offer
Breathalyzer technology is not new, but until now human breath detection devices have not been comparable to clinical laboratory blood testing for disease detection and monitoring. That may soon change and there are implications for clinical laboratories, partly because breath samples are considered to be non-invasive for patients.
Scientists with JILA, a research center jointly operated by the National Institutes of Standards and Technology (NIST) and the University of Colorado Boulder, recently increased the sensitivity of their laser frequency comb breathalyzer one thousand-fold. This created a device that can detect four disease biomarkers simultaneously, with the potential to identify six more, according to an NIST news release.
Medical laboratory scientists will understand the significance of this development. JILA’s enhanced breathalyzer device could pave the way for real-time, noninvasive breath analysis to detect and monitor diseases, and potentially eliminate the need for many blood-based clinical laboratory tests.
During their research, physicist Jun Ye, PhD, and David Nesbitt, PhD, both Fellows at JILA and professors at University of Colorado Boulder, detected and monitored four biomarkers in the breath of a volunteer:
These chemicals can be indicators of various health conditions. Methane in the breath, for example, can indicate intestinal problems.
The researchers say the JILA breathalyzer also could detect six additional biomarkers of disease without any further modifications to the device. They would include:
NIST/JILA Research Fellows Jun Ye, PhD (left), and David Nesbitt, PhD (right) of the University of Colorado Boulder, “built a breathalyzer that identifies biomarkers of disease by measuring the colors and amounts of light absorbed as a laser frequency comb passes through breath samples inside a glass tube,” according to an NIST news release. Should they succeed in creating a portable version, their noninvasive device could become an option compared to conventional clinical laboratory blood testing methods used to identify and monitor diseases. (Photos copyright: University of Colorado Boulder.)
“Determining the identity and concentration of the molecules present in breath is a powerful tool to assess the overall health of a person, analogous to blood testing in clinical medicine, but in a faster and less invasive manner,” the researchers wrote in PNAS.
“The presence of a particular molecule (or combination of molecules) can indicate the presence of a certain health condition or infection, facilitating a diagnosis. Monitoring the concentration of the molecules of interest over time can help track the development (or recurrence) of a condition, as well as the effectiveness of the administered treatment,” they added.
How the JILA Breathalyzer Detects Biomarkers
According to a 2008 NIST news release, JILA researchers had developed a prototype comb breathalyzer in that year. However, the research did not continue. But then the COVID-19 pandemic brought the JILA/NIST laboratories focus back to the breathalyzer with hopes that new research could lead to a breath test for detecting the SARS-CoV-2 coronavirus and other conditions.
“We are really quite optimistic and committed to pushing this technology to real medical applications,” Ye said in the 2021 NIST news release.
Analytical Scientist explained that JILA’s new and improved breathalyzer system “fingerprints” chemicals by measuring the amount of light absorbed as a laser frequency comb passes back and forth through breath samples loaded into a mirrored glass tube.
JILA’s original 13-year-old prototype comb analyzed colors and amounts of light in the near-infrared band. However, JILA’s recent improvements include advances in optical coatings and a shift to analyzing mid-infrared band light, allowing detection sensitivity up to parts-per-trillion level, a thousand-fold improvement over the prototype.
Corresponding study author Jutta Toscano, PhD, postdoctoral researcher at the University of Basel in Switzerland and previously Lindemann fellow at JILA, told Physics World the new frequency comb can “probe the molecular fingerprint region where fundamental, and more intense, spectroscopic transitions are found.
“By matching the frequency of the comb teeth with the cavity modes—the ‘standing modes’ of the cavity—we can increase the interaction path length between molecules inside the cavity and laser light by a factor of around 4000, equivalent to an effective path length of a few kilometers,” she added. “We then probe the light that leaks out of the cavity by sending it into an FTIR [Fourier-transform infrared] spectrometer to find out which exact comb teeth have been absorbed and by how much. In turn, this tells us which molecules are present in the breath sample and their concentration.”
Even Hippocrates Studied Breath
Ye noted in the NIST statement that JILA is the only institution that has published research on comb breathalyzers.
In their PNAS paper, the researchers wrote, “Breath analysis is an exceptionally promising and rapidly developing field of research, which examines the molecular composition of exhaled breath. … Despite its distinctive advantages of being a rapid, noninvasive technique and its long history dating back to Hippocrates, breath analysis has not yet been as widely deployed for routine diagnostics and monitoring as other methods, such as blood-based analysis.
“We have shown that this technique offers unique advantages and opportunities for the detection of light biomarkers in breath,” the researchers noted, “and it is poised to facilitate real-time, noninvasive monitoring of breath for clinical studies, as well as for early detection and long-term monitoring of temporary and permanent health conditions.”
Validation of these findings and further design research to make the system portable are required before JILA’s frequency comb breathalyzer can become a competitor to clinical laboratory blood tests for disease identification and monitoring. Nevertheless, JILA’s research brings breathalyzer technology a step closer to offering real-time, non-invasive analysis of human biomarkers for disease.
If tattoos can accurately be used in the diagnostic process, might clinical laboratories soon offer these types of diagnostic tattoos at their patient service centers?
Could color-changing tattoos help diagnose illnesses? Researchers at the ATLAS Institute at the University of Colorado Boulder think so. They are working on prototypes of permanent tattoos that can detect chemical changes in the body and smart tattoo ink that would take the concept of wearable medical devices to a whole new level.
Called “dynamic” or “smart” tattoos, these color-changing tattoos have a biomedical purpose. They alert individuals to potential health issues due to changes in the biochemistry in their body. The technology has already been used in animal studies to detect sodium, glucose, electrolytes, and pH levels. Pathologists and clinical lab manager will recognize the value of a relatively non-invasive way to measure and track changes in these types of biomarkers.
“We developed a photochromic tattoo that serves as an intradermal ultraviolet (UV) radiometer that provides naked-eye feedback about UV exposure in real time. These small tattoos, or ‘solar freckles’, comprise dermally implanted colorimetric UV sensors in the form of nano encapsulated leuco dyes that become more blue in color with increasing UV irradiance,” the ATLAS scientists wrote.
Studies analyzing the efficacy of dynamic tattoos have provided strong evidence that they can be engineered to change color and sense and convey medical information. This field is called “dynamic tattoos” and in recent years various proof-of-concept studies have demonstrated that tattoos can be used to “pick up changes in sodium, glucose, electrolytes or pH levels in animal models,” Labroots reported.
“We demonstrate the tattoos’ functionality for both quantitative and naked-eye UV sensing in porcine skin ex vivo, as well as in human skin in vivo. Solar freckles offer an alternative and complementary approach to self-monitoring UV exposure for the sake of skin cancer prevention,” the researchers explained in their ACS Nano article.
“Activated solar freckles provide a visual reminder to protect the skin, and their color disappears rapidly upon removal of UV exposure or application of topical sunscreen. The sensors are implanted in a minimally invasive procedure that lasts only a few seconds yet remain functional for months to years,” they added.
“These semipermanent tattoos provide an early proof-of-concept for long-term intradermal sensing nanomaterials that provide users with biomedically relevant information in the form of an observable color change,” the ATLAS researchers concluded.
“When you think about what a tattoo is, it’s just a bunch of particles that sit in your skin,” Carson Bruns, PhD, Assistant Professor, Laboratory for Emergent Nanomaterials, ATLAS Institute, Mechanical Engineering, told Technology.org. “Our thought is: What if we use nanotechnology to give these particles some function?”
The invisible tattoos Bruns and the ATLAS team created turn blue in the presence of harmful levels of ultraviolet radiation to inform wearers that their skin needs protection and to apply or reapply sunscreen.
“I have always been interested in both art and science. My favorite type of art is tattooing and my favorite type of science is nanotechnology,” Carson Bruns, PhD (above), Assistant Professor, Mechanical Engineering, ATLAS Institute, told Inked. “When I had an opportunity to start a new research program, I thought it would be really fun and interesting to try and put the two together.” Might innovative medical laboratories one day operate “tattoo parlors” in their patient service centers to provide patients with tattoos that monitor key biometrics? (Photo copyright: Inked.)
The tattoo ink used for these tattoos contains a UV-activated dye inside of a plastic nano capsule that is less than a thousandth of a millimeter in size, or several sizes smaller than the width of a human hair. The capsules protect the dyes from wear and tear while allowing them to sense and respond to biochemical changes in the body. These tattoos are implanted into the skin using tattoo machines, much like getting a regular tattoo.
“I call them solar freckles because they’re like invisible freckles that are powered by sunshine,” Bruns told Inked, adding, “Millions of cases of preventable skin cancer are treated every year. I hope that the UV-sensitive tattoo will help us reduce the number of those cases by reminding people when their skin is exposed to unsafe levels of UV light.”
Dynamic Tattoos May Help People Lead Healthier Lives
One downside to these tattoos is that they only last a few months before they begin to degrade, requiring the wearer to get a “booster” tattoo.
The researchers hope that someday similar tattoo technologies will be applied to a wide variety of preventative and diagnostic applications. The goal is to enable people to detect health issues and allow them to lead healthier lives.
“We want to make tattoos that will allow you to, for example, sense things that you can’t currently sense,” Bruns told Inked. “Sometimes I joke that we want to make tattoos that give you superpowers.”
The ATLAS scientists imagine a future where tattoos can detect things like blood alcohol levels or high/low blood sugar levels or other changes in a person’s biochemistry.
“More generally, I hope that smart tattoos will help people stay healthy and more informed about their body, while also giving people new ways to express themselves creatively,” Bruns said.
Using Dynamic Tattoo to Detect Cancer
In 2018, a team of biologists created a tattoo comprised of engineered skin cells and an implantable sensor which could detect elevated blood calcium levels that are present in many types of cancers. These cancer-detecting tattoos were tested on living mice and would darken to notify researchers of potential problems.
Scientists at the Department of Biosystems Science and Engineering at the Swiss Federal Institute of Technology Zurich (ETHZ), Switzerland, developed a biomedical tattoo that uses bio sensitive ink and changes color based on variations in the body’s interstitial fluid. It recognizes four widespread cancers:
breast,
colon,
lung, and
prostate.
“Nowadays, people generally go to the doctor only when the tumor begins to cause problems. Unfortunately, by that point it is often too late,” Martin Fussenegger, PhD, Professor of Biotechnology and Bioengineering at the Department of Biosystems Science and Engineering (D-BSSE) of the ETH Zurich in Basel as well as at the University of Basel, told Medical News Today.
“For example, if breast cancer is detected early, the chance of recovery is 98%,” he continued. “However, if the tumor is diagnosed too late, only one in four women has a good chance of recovery.”
Though it appears that dynamic tattoos may be a functional and decorative way to track health, rigorous research and safety testing on human subjects will be required before clinical laboratories can set up diagnostic tattoo parlors in their offices.
Nevertheless, this concept demonstrates how different technologies under development may provide clinical laboratories with innovative and unusual diagnostic tools in the future.
