A pair of wearable stickers may transform diagnostic sweat testing for cystic fibrosis (CF), a genetic disorder that causes problems with digestion and breathing. The innovative technology was found to be reliably accurate compared to standard sweat testing, according to the study published in npj Digital Medicine journal .
Small, flexible and gentle on babies’ delicate skin, the sweat test stickers are less expensive, simpler to use and do not require specialized lab equipment or technical expertise, in contrast to the standard sweat testing process primarily available in accredited CF centers at children’s hospitals. This means potentially greater access to the diagnostic test and timely treatment, especially for babies living in rural areas far from a CF center or lower income countries where testing availability is limited.
“It has been estimated that about half of people with CF around the world have not been diagnosed. Without treatment, their life expectancy is less than 5 years of age. This is in stark contrast to 66 years, which is the projected median age of survival with treatment in the US currently,” said co-senior author Susanna McColley, MD , CF expert at Ann & Robert H. Lurie Children’s Hospital of Chicago and Professor of Pediatrics at Northwestern University Feinberg School of Medicine.
“The new technology, developed by the bioengineering team of John Rogers at Northwestern University’s Querrey Simpson Institute for Bioelectronics, in close collaboration with our cystic fibrosis center team, promises to make diagnostic testing for CF more readily available. This is critical, since earlier diagnosis is linked to better health outcomes and longer life,” she stressed.
Diagnostic testing for CF measures sweat chloride. In the new system, the first sticker stimulates sweat production using a chemical and a button battery, while the second sticker is applied to the same spot to collect the sweat for analysis. An image of the sticker is used by a smartphone app to analyze chloride content and through precise measurement of changes in color density. The entire procedure takes less than an hour to complete.
"This latest paper is a real advance over our previous report in Science Translational Medicine , which showed that sweat chloride could be accurately measured on a sticker after sweat stimulation using current technology. The new "CF SWIFT" device is a complete self-contained system, including the soft stimulator unit, with a much larger population of children studied and proof of clinical accuracy in measuring chloride," said John Rogers , co-senior author on the study.
The current study included 55 participants – three healthy volunteers and 52 people with CF or CF related conditions, with ages ranging from infancy to 21 years. Participants were tested using both the traditional sweat testing method and the new sticker technology.
“We found a high correlation in the results between the two methods, which demonstrates that the new technology reliably reflects sweat chloride measurements used for diagnosis of CF,” said Dr. McColley. “Before these sweat testing stickers become clinically available, however, we need to validate our findings in a multicenter study with younger infants, since most sweat tests in the US are performed in the first weeks of life. Of course, FDA approval will be necessary for clinical use.”
Ann & Robert H. Lurie Children’s Hospital of Chicago is a nonprofit organization committed to providing access to exceptional care for every child. It is the only independent, research-driven children’s hospital in Illinois and one of less than 35 nationally. This is where the top doctors go to train, practice pediatric medicine, teach, advocate, research and stay up to date on the latest treatments. Exclusively focused on children, all Lurie Children’s resources are devoted to serving their needs. Research at Lurie Children’s is conducted through Stanley Manne Children’s Research Institute, which is focused on improving child health, transforming pediatric medicine and ensuring healthier futures through the relentless pursuit of knowledge. Lurie Children’s is the pediatric training ground for Northwestern University Feinberg School of Medicine. It is ranked as one of the nation’s top children’s hospitals by U.S. News & World Report .
npj Digital Medicine