A groundbreaking nasal swab test promises to transform the diagnosis and treatment of childhood asthma by identifying specific immune system drivers behind the condition. Researchers believe this innovation could pave the way for more effective, tailored therapies for children suffering from this common chronic disease.

The test, developed by researchers at UPMC Children’s Hospital of Pittsburgh, diagnoses asthma subtypes, or endotypes, by analyzing a simple nasal sample. According to senior researcher Dr. Juan Celedon, chief of pulmonary medicine at the hospital, accurate identification of an asthma endotype is crucial for improving treatment outcomes. “Because asthma is a highly variable disease with different endotypes, which are driven by different immune cells and respond differently to treatments, the first step toward better therapies is accurate diagnosis of endotype,” Dr. Celedon said in a hospital news release.

Asthma affects approximately one in ten children in the United States, making it the most common chronic disease among youth, according to the National Institutes of Health. Traditionally, doctors classify asthma into three primary subtypes based on the immune cells causing airway inflammation: T2-high, driven by T helper 2 cells; T17-high, driven by T helper 17 cells; and low-low, where neither cell type predominates.

Current methods for precise endotype diagnosis involve invasive procedures like obtaining lung tissue samples under anesthesia for genetic analysis. These procedures are rarely conducted in children with mild asthma, leaving physicians to estimate asthma subtypes based on blood tests, lung function, and allergy assessments. However, these methods lack the precision to differentiate between T17-high and low-low asthma, Dr. Celedon explained. “This gap motivated us to develop better approaches to improve the accuracy of asthma endotype diagnosis,” he said.

The new study, published on January 2 in the Journal of the American Medical Association, analyzed nasal samples from nearly 460 children, focusing on eight genes linked to T2 and T17 immune cells. These samples were drawn from three independent U.S. studies, with a particular emphasis on Puerto Rican and African American children—populations with higher asthma prevalence and mortality rates.

Results showed the nasal swab test could accurately identify asthma subtypes, potentially steering children with T2-high asthma toward effective new drugs targeting the immune cells responsible for their condition. Researchers found that 29% of the children studied had T2-high asthma, which can now be more readily managed with targeted biologic therapies. Unfortunately, no similar treatments currently exist for T17-high or low-low asthma.

Dr. Celedon expressed optimism about future research opportunities facilitated by the nasal swab test. “Now that we have a simple nasal swab test to detect other endotypes, we can start to move the needle on developing biologics for T17-high and low-low disease,” he said. The test also holds promise for broader asthma research, including understanding why asthma worsens during puberty for some children and improves for others. “Is this related to endotype? Does endotype change over time or in response to treatments? We don’t know. But now that we can easily measure endotype, we can start to answer these questions,” Dr. Celedon concluded.

This non-invasive, quick, and accurate diagnostic tool could revolutionize asthma management in children, offering new hope for tailored treatments and improved outcomes in this vulnerable population.