As a health and science reporter, I’ve studied the maze of U.S. health care. But when my son got sick, I still got lost. Staff writer January 30, 2023 at 6:30 a.m. EST Evan, 3, has systemic onset juvenile idiopathic arthritis. After a few weeks on a drug called anakinra, he could walk and play, but the insurance company refused to cover it. (Courtesy of Carolyn Y. Johnson) Comment on this story Comment When a salmon-colored rash flared on my 3-year-old son’s tummy one afternoon in August, I shrugged it off. The next time I asked Evan to lift up his shirt to take a photo, it was gone. When…