SAVI causes blistering and organ damage, but pinpointing culprit DNA offers hope
FRIDAY, July 18, 2014 (HealthDay News) -- Researchers say they've identified a gene mutation tied to a rare but severe, and often fatal, disease in children.
The disease is called STING-associated vasculopathy with onset in infancy (SAVI). It's an autoinflammatory disease, involving an immune-system malfunction that causes prolonged inflammation that in turn can damage the body.
In 2004, Dr. Raphaela Goldbach-Mansky of the U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS) was asked to assist in the case of a 10-year-old girl with SAVI that had not responded to any medications.
The girl had blistering rashes on her fingers, toes, ears, nose and cheeks and had lost parts of her fingers. She also had severe scarring in her lungs and was having breathing problems. She died a few years later.
By 2010, Goldbach-Mansky had seen two more children with the same symptoms and suspected that all three patients had the same disease. She suspected it was caused by a genetic defect that occurred in the children, rather than being inherited from their parents, who were not affected.
Investigating further, Goldbach-Mansky's team compared the DNA of affected children with the DNA of their parents. The researchers zeroed in on a mutation in a gene that produces a protein called STING. The mutation results in overproduction of an important immune system regulator called interferon. According to the researchers, too much interferon can trigger runaway inflammation.
The discovery doesn't have practical implications for patients right now, but it could be a crucial step forward, the experts said.
"Not only do these discoveries have profound implications for children with SAVI, but they could have a broader impact by helping us to understand other, more common inflammatory conditions," NIAMS Director Dr. Stephen Katz said in an institute news release.
"Diseases such as lupus share some characteristics with SAVI, so this work may lead to novel insights and possibly new treatments for these debilitating conditions as well," he explained.
In laboratory studies, several existing drugs have shown promise against SAVI, and one is currently being tested in children with the disease, the researchers said.
The U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases has more about autoinflammatory diseases (http://www.niams.nih.gov/Health_Info/Autoinflammatory/default.asp ).
SOURCE: U.S. National Institute of Arthritis and Musculoskeletal and Skin Diseases, news release, July 16, 2014