Oct. 4 (UPI) — Researchers at the California Institute of Technology developed a new test that can identify antibiotic-resistant bacteria in as little as 30 minutes.
Overuse and misuse are causing antibiotics to lose their effectiveness while, at the same time, many types of bacteria have evolved resistance to commonly used antibiotics. Multi-drug resistant bacteria or superbugs have emerged leading to concerns and warning from the healthcare community.
“Right now, we’re overprescribing, so we’re seeing resistance much sooner than we have to for a lot of the antibiotics that we would otherwise want to preserve for more serious situations,” Nathan Schoepp, a Caltech graduate student,.
Current tests for antibiotic resistance take two to three days because a sample has to be sent to a lab for testing.
The new test uses a urine sample collected from a patient with a urinary tract infection and is divided into two parts. The first part is exposed to an antibiotic for 15 minutes, while the second part incubates without antibiotic exposure.
The research wastoday in Science Translational Medicine.
The bacteria from each sample is then broken open to release its cellular contents, which are run through a process that combines a detection chemistry technique digital real-time loop-mediated isothermal amplification, or dLAMP, with a SlipChip device. The process replicates specific DNA markers so they can be imaged and individually counted as discrete fluorescent spots appearing on the chip.
If the bacteria are resistant to the antibiotic, their DNA replication will not be hampered and the test will show similar numbers of DNA markers in both the treated and untreated solutions.
Researchers used the new test on 54 samples of urine from patients with UTIs that were caused by the bacteria Escherischia coli. Results showed a 95 percent match with results obtained from using standard two-day test methods.
Doctors treating patients with bacterial infections often skip over first-line antibiotics like methicillin or amoxicillin and go for stronger second-line antibiotics like ciprofloxacin, increasing the effectiveness of the treatment while also increasing the risk of antibiotic resistance.
“Therapies are driven by guidelines developed by organizations like the World Health Organization or the Centers for Disease Control and Prevention without knowing what the patient actually has, because the tests are so slow,” Rustem Ismagilov, a professor of Chemistry and Chemical Engineering and director of the Jacobs Institute for Molecular Engineering for Medicine at Caltech, said. “We can change the world with a rapid test like this. We can change the way antibiotics are prescribed.”