pediatrics
Rett Syndrome
Diagnosis of Rett Syndrome
Clinical evaluation Genetic testing Diagnosis of Rett syndrome is made clinically by observing symptoms and signs during the child’s early growth and development. Ongoing evaluation of the child’s physical and neurologic status is needed. Genetic testing for theMECP2gene mutation on the X chromosome (Xq28) and for other potentially confounding genetic mutations is used to complement the clinical diagnosis. Explicit guidelines are used to confirm the clinical diagnosis of Rett syndrome. These guidelines divide the clinical diagnostic criteria into required, main, supportive, and exclusion ( Diagnosis reference ). Therequired diagnostic criteriaare all of the following: A period of regression followed by recovery or stabilization (critical criterion) All main criteria All exclusion criteria Themain diagnostic criteriaare loss of all or part of purposeful hand skills, repetitive hand movements (such as wringing or squeezing, clapping or rubbing), loss of all or part of spoken language, and gait abnormalities including toe-walking or an unsteady, wide-based, stiff-legged walk. Theexclusion diagnostic criteriaare the presence of other disorders that cause similar symptoms, including traumatic brain injury, grossly abnormal psychomotor development during the first 6 months of life, neurometabolic disease, and severe infection causing neurologic problems. Thesupportive diagnostic criteriainclude awake breathing disturbances; scoliosis or kyphosis; awake bruxism; abnormal sleep patterns; cold, small hands and feet in relation to height; peripheral vasomotor disturbances; growth retardation; abnormal muscle tone; intense eye communication ("eye pointing"); inappropriate laughing or screaming; and decreased response to pain. Although supportive criteria are not required for a diagnosis of typical Rett syndrome, they may occur in some children with a diagnosis of typical Rett syndrome and can also help lead to a diagnosis of atypical Rett syndrome. A child who has had a period of regression followed by recovery or stabilization, who has all exclusion criteria, and who has at least 2 main criteria plus at least 5 supportive criteria has atypical Rett syndrome. 1.Neul JL, Kaufmann WE, Glaze DG, et al: Rett syndrome: Revised diagnostic criteria and nomenclature.Ann Neurol68(6):944–950, 2010. doi: 10.1002/ana.22124 