As originally reported in Fabry Disease News, the potentially fatal genetic disorder Fabry disease can be diagnosed most effectively in infancy by newborn screening programs. By identifying the disease early, the patient can be put into enzyme replacement therapy to stop the progression that damages the tissues and organs.
Fabry disease is a lysosomal storage disease in which the fat globotriaosylceramide cannot be processed by the body and builds up in the cells. This excess can cause symptoms such as kidney damage, strokes, or a heart attack- making the disease potentially fatal. Other common symptoms include pain in feet or hands, dark red spots, hearing loss or ringing, cloudy vision, gastrointestinal issues, and the inability to sweat. While some patients experience acute symptoms later in life, others can start to show signs in childhood.
Benefits of Early Diagnosis
Early diagnosis allows patients to access the available enzyme replacement therapies (ERT), which include Replagal, Fabrazyme, and Galafold. These therapies treat the symptoms that lead to kidney and heart disease before they progress to critical stages. ERT can potentially prevent the spiral into fatal situations, but there’s a critical window to treatment. If the symptoms have already become present, the organs lose their functioning. Many patients and families fail to find the disease before the symptoms make themselves known or receive a misdiagnosis. New research has found that accessing the treatment prior to the disease’s manifestation is “critical to preserve organ function.”
Japan’s Newborn Screening Program
In Japan, a new newborn screening program was implemented to find the disease early. The screening, which uses alpha-GAL A activity assays, checks for low enzyme activity using blood samples. If the first test is positive, they’ll be checked again, and after two positive tests, the babies will go for further genetic testing and sequencing for clear confirmation. In Japan, they found that the disease occurs in one in 7,683 live births. In the experiment, 984 newborns came back positive from the first blood sample, and only 138 were positive after the retesting. These babies went on to the more extensive genetic testing.
Other Family Members’ Diagnosis Identified
In the study, the newborn screenings found 37 babies with the disease causing variant, and three of them developed symptoms. This led the family members of the three affected patients to get tested and identify their own mutations. The three mothers each had the mutation and got treated with ERT, as well as one grandfather.
Researchers concluded that not only are the newborn screenings the easiest way to find the disease, they are also the safest way to guarantee the patients a safe, symptom-free life before it becomes irreversible.