(KXAN) — The U.S. Food and Drug Administration has authorized testing to aid in newborn screenings of Duchenne Muscular Dystrophy, a rare genetic disorder that causes progressive muscle deterioration and weakness.
The test comes after national efforts to harmonize screening practices across Texas.
The new test for DMD will be added to the Recommended Uniform Screening Panel (RUSP), a list of core and secondary conditions for screening newborns, per recommendations from the U.S. Dept. of Health and Human Services.
Testing allows for laboratories to add DMD to its screening panel for newborns if they choose to do so.
The test, called the GSP Neonatal Creatine Kinase-MM kit, works by measuring the concentration of creatine kinase proteins in the blood. Creatine kinase is found in muscle tissues. This protein enters the bloodstream in increased amounts when muscle damage is present.
By taking dried blood samples from newborns 24 to 48 hours after birth, it can show if levels are consistent with DMD. Although elevated levels can indicate a presence of DMD, further testing is needed in order to formally diagnose the disorder.
According to the FDA, the organization evaluated data from a clinical study of nearly 3,100 newborns whose dried blood samples were tested for protein levels consistent with DMD. In this study, the kit was able to accurately identify four newborns with DMD-causing genetic mutations.
The manufacturer of the kit also tested 30 newborns with confirmed cases of DMD. All were correctly identified by the test.
While DMD is a rare genetic condition, it’s the most common form of muscular dystrophy. It’s caused by the absence of dystrophin, a protein that helps keep muscle cells together.
Symptoms are typically seen between the ages of 3 and 5, and worsen over time. The disease often occurs in people without known family history, and more commonly in boys. The average life expectancy ranges from 20 to 30 years. As the disease progresses, life-threatening heart and respiratory conditions can occur as well.
DMD occurs in 1 in 3,600 male live-born infants worldwide.
The U.S. Centers for Disease Control (CDC) advises early detection so that more personalized care for patients with muscular dystrophy. On average, it takes two years from noticing the early symptoms to getting a formal diagnosis.
With this test, the FDA will be establishing criteria, called special controls, for test of this type to be met. This includes design verification, validation, and labelling reuirements, as well as new regulatory classifications for subsequent devices for similar testing in the future.