Triosephosphate isomerase deficiency (TPI deficiency) is a rare genetic disorder that affects the metabolism of glucose in the body. It is an autosomal recessive disorder, meaning that an individual must inherit two copies of the mutated gene, one from each parent, to develop the condition. TPI deficiency primarily affects the red blood cells, muscles, and the central nervous system.
Anemia: One of the hallmark symptoms of TPI deficiency is chronic hemolytic anemia. Hemolytic anemia occurs when red blood cells are destroyed faster than they can be produced. This leads to a reduced number of red blood cells, causing fatigue, weakness, pale skin, and shortness of breath.
Neurological symptoms: TPI deficiency can also affect the central nervous system, leading to various neurological symptoms. These symptoms may include developmental delay, intellectual disability, muscle weakness, poor coordination, and difficulty with movement. In severe cases, individuals may experience seizures or loss of sensation in the limbs.
Muscle problems: TPI deficiency can cause muscle weakness and muscle wasting. Affected individuals may have difficulty with activities that require muscle strength, such as walking, running, or lifting objects. Muscle pain and cramps may also occur.
Respiratory problems: Some individuals with TPI deficiency may experience respiratory difficulties, such as shortness of breath or rapid breathing. This can be due to the reduced oxygen-carrying capacity of the blood caused by anemia.
Enlarged liver and spleen: In some cases, TPI deficiency can lead to hepatosplenomegaly, which is the enlargement of the liver and spleen. This can cause abdominal discomfort or pain.
Heart problems: Rarely, TPI deficiency may be associated with heart abnormalities, including an enlarged heart (cardiomegaly) or irregular heart rhythms (arrhythmias).
Other symptoms: Additional symptoms that may be present in individuals with TPI deficiency include recurrent infections, poor growth, skeletal abnormalities, and hearing loss.
TPI deficiency is a progressive disorder, meaning that symptoms tend to worsen over time. The severity of the symptoms can vary widely among affected individuals, even within the same family. Some individuals may have mild symptoms and lead relatively normal lives, while others may experience severe disability and have a reduced life expectancy.
Diagnosis of TPI deficiency is typically confirmed through genetic testing, which can identify mutations in the TPI1 gene. Treatment options for TPI deficiency are limited, and management primarily focuses on alleviating symptoms and providing supportive care. This may include blood transfusions to address anemia, physical therapy to improve muscle strength and coordination, and medications to manage seizures or other associated complications.