Neurological infections are among the most difficult to Diagnostic, especially when caused by rare or unknown pathogens: and every day without a correct diagnosis can mean an irreversible worsening for the patient. But science has made a giant step: a new genomic testing developed at the University of California, San Francisco (Ucsf) is now able to identify any type of pathogen by analyzing the DNA present in a single sample.
The technology, which has already demonstrated very good accuracy, could change the way we diagnose infections.
How does genomic testing work?
The new method is based on the next-generation metagenomic sequencing (mNGS), a technique that simultaneously analyzes all the genetic material present in a sample. As explained by the Dr. Charles Chiu, professor of laboratory medicine and infectious diseases at theUcsf:
Our technology is really simple. By replacing multiple tests with a single test, we can take the guesswork out of diagnosing and treating infections.
The test was initially developed to analyze the cerebrospinal fluid, achieving surprising results. Unlike traditional methods, which look for one specific pathogen at a time, this technology simultaneously examines all the genetic material present in the sample, providing a complete picture in record time.
An illuminating case study
In 2014, this (still embryonic) technology demonstrated its value in a dramatic way. A young patient in Wisconsin was in critical condition in intensive care, and a long series of conventional tests had failed to identify the cause of his illness.
The team ofUcsf ran a sample through their genomic test, and within two days the culprit was identified: leptospirosis, an infection treatable with penicillin. First life saved, and it wasn't as accurate as it is today.
Results that speak for themselves
Between 2016 and 2023, the team of theUcsf he analysed nearly 5.000 cerebrospinal fluid samples. 14,4% of these had an infection, and the test was able to correctly identify the pathogen in 86% of cases. These impressive numbers have pushed the FDA to grant the test the designation of “breakthrough device.” The accuracy and reliability demonstrated in this large study are a significant advance in medical diagnostics.
The innovation doesn't stop there. Researchers have adapted the genomic test to analyze respiratory fluids, automating it to get faster results. The process, which previously required over 100 steps and up to 7 days, now only takes 30 minutes of manual intervention before robots and algorithms can complete the analysis. This optimization is crucial for rapid response to health emergencies.
Anticipating future threats
The study published in Nature Communications. (I link it here) has shown that the test can detect viruses with pandemic potential, including COVID-2, influenza A and B e RSV, in less than 24 hours, even with tiny amounts of virus in the sample. But the real breakthrough is its ability to identify new viral variants before they become a global threat. Researchers simulated the test’s ability to detect divergent viruses (recently evolved strains) and found that it could theoretically identify any new variant.
The impact on modern medicine
To make this technology more accessible, Chiu and his colleagues founded Delve Bio, which is now the exclusive provider of the mNGS test for cerebrospinal fluid developed atUcsf. As stated by the Dr. Steve Miller, medical director of Delve Bio:
The mNGS test offers the most unbiased, comprehensive and definitive tool for pathogen detection. With its ability to rapidly diagnose an infection, it helps guide management decisions and patient treatment.
Genomic testing, towards a safer future
The impact of this technology extends far beyond individual diagnosis. Its ability to rapidly identify new pathogens could revolutionize our response to global health emergencies.
I am particularly struck by how this test combines scientific precision with clinical practicality, offering a tool that not only improves the diagnosis of neurological infections but could also prevent future pandemics. We are on the threshold of a new era in diagnostic medicine.
