Tarui Disease

Tarui Disease or Phosphofructokinase Deficiency is a muscular metabolic disorder that interferes with the processing of food. It was first described by Japanese physician Seiichiro Tarui in 1965.

It is also known as phosphofructokinase deficiency or glycogen storage disease type VII. Deficiency of this enzyme leads to accumulation of glycogen in the tissues. There is inability to break down glycogen. It is a rare condition and is mostly inherited; worldwide very few cases have been reported. Uric acid production may go up; thereby leading to Gout and also to Hemolytic Anemia.

The disease is presented as:

Classic: most common type of this disease includes intolerance for exercises.

Late onset: sets in late and does not have many indications as present in the classic form other than muscle and limb weakness.

Infantile: sets in infants , infants with this condition hardly survive, this is condition is rarely reported.

Symptoms are very mild and may go completely unnoticed. There is intolerance for exercise as well as pain and cramps while exercising. In rare cases, there is acute muscle breakdown or myoglobinuria. A meal rich in carbohydrates can worsen the symptoms as it reduces the fat level in the blood.

In Classic cases, the symptoms appear in early childhood - nausea, vomiting after heavy exercise and jaundiced appearance. In late onset cases, weakness, fatigue and Myopathy are noticed. When there is Infantile form of Tarui Disease, the symptoms can vary. Phosphofructokinase deficiency infants exhibit respiratory issues. If it presents itself in the central nervous system, symptoms include seizures.

There is no specific treatment. Avoid strenuous exercises to avoid muscle cramping and pain. Reduce intake of carbohydrates. High protein intake helps in improving muscle function and slow progression of the disease. Ketogenic diet is prescribed that includes high fat and low carb thus enabling the body to derive energy from fatty acids instead of glucose.