A genetic biomarker of asthma collected from a nasal swab can accurately diagnose asthma in patients with mild to moderate symptoms. The identification of this biomarker using the swab can also differentiate between asthma and other respiratory diseases, including allergic rhinitis, upper respiratory infections and cystic fibrosis.
“Our nasal classifier of asthma represents a novel path to diagnosing asthma with a simple nasal brush,” Supinda Bunyavanich, MD, MPH, MPhil, associate professor of allergy and immunology at the Icahn School of Medicine at Mount Sinai, told Infectious Diseases in Children. “It takes seconds to perform a nasal brushing, and interpretation of data gained from this brushing can be automated based on an algorithm we identified, yielding an output of asthma or no asthma.”
According to Bunyavanich, asthma is typically diagnosed based on patient reports, which can be challenging because most patients with mild to moderate asthma are not symptomatic. She said that while pulmonary function testing can assist in the diagnosis of asthma, this step is often not performed in primary care settings due to lack of equipment, time and expertise.
“And people who may have asthma often underperceive and underreport symptoms,” she added.
Bunyavanich and colleagues examined nasal swabs collected from two groups of participants — an asthma group (n = 66) and a control group (n = 124) — using a brush that would later be studied for biomarkers of mild to moderate asthma using RNA sequencing. After applying machine-learning algorithms to the RNA data, the researchers identified a 90-gene biomarker that can assist in the accurate diagnosis of mild to moderate asthma. When the test was used on patients who had asthma and additional respiratory conditions, the researchers observed a high accuracy, sensitivity and specificity for asthma.
According to Bunyavanich, once the nasal brush has been collected, the cost of profiling is less than $100. She mentioned that costs are likely to decrease in the future. No additional equipment would be required for the technology’s use.
“We envision implementation of our nasal classifier of asthma in pediatric and adult health care settings,” she said. “Implementation of this diagnostic testing would include the doctor gently brushing a patient’s nose with a nasal brush, which would then undergo automated interpretation. A positive or negative readout would then shortly follow, which the doctor could factor into his or her clinical assessment of the patient.” – by Katherine Bortz
Disclosures: Bunyavanich has filed a patent application related to the study’s findings. Please see the study for all other authors’ relevant financial disclosures.