12-year-old    8-year-old boy    biological factors    body’s own immune response    boy    carlo carandang    cases of children    clinical psychologist    creighton university    danish teen girls    day.the boy    dead animals    disorder.other researchers    eating disorder    fat cells    food labels    girls’ medical records    greatest risk    healthy eating    hospital    lancaster university    large study    late 1990s    lauren breithaupt    mae sokol    massachusetts general hospital    north carolina    nova scotia    obsessive-compulsive disorder    past them.the boy’s symptoms    patient’s gut microbiome    pediatric autoimmune neuropsychiatric disorders    people    psychiatry professor    psychological aspects    psychological factors    psychological symptoms    rheumatic fever    series of upper-respiratory-tract infections    social factors    strep infections    strep throat    streptococcal infection    type of obsessive-compulsive disorder    unanswered questions    united kingdom    united states    untreated upper-respiratory-tract infection    unusual patient    weight gain