The "thumb sign" in children.
D000293:Adolescent; D000592:Amino Acid Metabolism, Inborn Errors / Q000175:diagnosis; D002648:Child; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004314:Down Syndrome / Q000175:diagnosis; D006712:Homocystinuria / Q000175:diagnosis; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis; D008382:Marfan Syndrome / Q000175:diagnosis*; D013933:Thumb