#tpk1

Could a child who seems to have autism, encephalitis, or developmental regression actually have a treatable metabolic disorder? This article explains THMD5, a rare inborn error of metabolism caused by TPK1 deficiency that can mimic autism-like symptoms, recurrent encephalopathy, language loss, and regression after fever or infection. Learn how thiamine metabolism works, why THMD5 is often missed, how it is diagnosed, and why early recognition and treatment may change long-term outcomes.