Thiamine pyrophosphokinase (TPK) deficiency is a recently described rare disorder that has episodic encephalopathy or Leigh syndrome like early-onset global developmental delay. TPK deficiency is one of thiamine metabolism dysfunction syndrome caused by TPK1 mutations. TPK produces thiamine pyrophosphate (TPP). TPP is a cofactor for enzymes important in a range of fundamental processes such as cellular respiration. It has been reported that early thiamine supplementation prevented encephalopathic episodes and improved developmental progression.
