Bacterial sensor could help treat infections
Los Alamos group hopes to create device to aid doctors with quicker diagnosis
When Harshini Mukundan’s nephew was just a couple of months old, the baby boy was diagnosed with meningitis.
The disease is serious. It causes swelling of the tissue around the brain and spinal cord and can be fatal. To complicate matters, meningitis can be either viral or bacterial — but determining the type of infection a patient has is not easy.
“It was a really scary time for all of us,” said Mukundan, a scientist at Los Alamos National Laboratory, speaking of the infant’s illness. “They pumped that little newborn full of antibiotics because they didn’t know if it was bacterial.”
In the end, her nephew didn’t need the antibiotics. The meningitis was viral, and his body fought it off.
Mukundan’s research team at Los Alamos aims to help doctors and patients worldwide move beyond that frustrating guessing game. The group is working to develop a bacterial sensor to allow doctors to quickly determine the type of infection that is ailing a patient.
“Immediate diagnostics that can
guide decision-making at that point are unavailable,” Mukundan said.
Because different classes of bacteria are best treated with different types of antibiotics, she added, such a device could ensure speedier and more effective treatment of diseases. “I think we can actually make an impact on health care,” she said.
So far, her team has been able to diagnose prototypes of different categories of bacterial infections.
While the testing system won’t be able to identify a patient’s specific bacterial disease, it could help launch initial treatment and inform further diagnostic tests. Mukundan described it as a triage tool.
“Our holy grail is not to learn exactly what disease is going on,” she said. “Timely decision-making to save lives is the goal.”
In their effort to detect bacteria, the Los Alamos researchers are mimicking the body’s approach. They look for molecules that signal interactions between different types of bacteria and their host’s immune system.
“For all of our technology, we can’t tell right away if an infection is viral or bacterial, but if you look at our immune system, it can,” Mukundan said. “I do believe that nature has an answer to pretty much everything.”
The future applications for such a diagnostic test could be abundant. For example, said Jessica Kubicek-Sutherland, a postdoctoral researcher on the team, doctors currently have a hard time telling the difference between bacterial sepsis and heart disease, which have similar symptoms.
“The very best hospital in the world could do that diagnosis in four hours,” Kubicek-Sutherland said. “That’s a long time when you’re dying.”
The Los Alamos team’s next step forward center on the project is packaging the most efficient testing equipment possible.
Right now, team chemist Aaron Anderson said, the tests require administrators to have knowledge of a specially designed computer system and spit out information that might be too detailed for practical use in the field.
“I’d like to simplify that to a point,” said Anderson, who is helping to build the diagnostic machine. “The clinician just wants to know whether this person has disease A, B or C.”
The hardware itself needs some upgrades, too. The biosensor the team uses to conduct the tests is a bulky machine — not ideal for environments such as Kenya, where one of the lab’s field sites is known to lose power for hours on end.
The researchers hope to design a small, handheld device that would give a doctor a bacterial reading within an hour of inserting one drop of a patient’s blood.
Together, they think they can make that happen.
Mukundan’s team — composed of biologists, chemists and consultants or partners from every other scientific discipline needed for designing and developing the tests and devices — hopes to have a prototype built by the end of 2018.
Eventually, they plan to add viral illness detection to the diagnostic tool.
“When you go to the doctor’s office, and you have some random [treatment] — that ‘go home, take some of these and call me in the morning’ — that’s not satisfying,” Anderson said, and it can mean the difference between life and death for patients.
“It’s a win-win for everybody,” he said, “if we can come up with a more definitive answer for making our health care decisions.”
Contact Sami Edge at 505-9863055 or sedge@sfnewmexican.com.