What is homocystinuria?

Homocysteinuria, also known as cystathionine β - synthetase deficiency, is a genetic disease caused by the disorder of methionine metabolism If not diagnosed and treated in time, children born with the disease are at risk for intellectual disability, epilepsy and thromboembolism At present, there is no cure for homocystinuria, but early treatment can prevent the symptoms from further deterioration Homocystinuria is an autosomal system This means that the genes involved in the development of disorders are not located on the sex chromosome In addition to the fact that the disorder is recessive, it also means that children born with the disorder inherit defective copies from their parents The disease is rare, with an incidence rate of around 34 1 Cystathionine β - synthases deficiency is a multisystem disease, which means it affects different systems of the body Patients can't adapt to methionine, which can lead to the accumulation of proteins called homocysteine, damage the elastin and collagen fibers of various types of muscles, and poison brain tissue People with this disease have a shorter life span, especially if they are diagnosed later Symptoms of homocystinuria are manifested in the central nervous system and cardiovascular system, as well as in muscles and connective tissue Symptoms of the disease include mental retardation, increased risk of thrombosis and mental illness, seizures, glaucoma, myopia, atrophy of the eye muscles, and arterial swelling Children born with the disease also have physical characteristics of long limbs, genu valgus and high arches Homocystinuria can not be cured, but can be controlled by proper diet and specific drugs About 50% of patients can be effectively treated by regular high-dose vitamin B6 If there is no positive response to this treatment, you may need to follow a specific diet The recommended diet is low protein, especially methionine and specific amino acids This diet can help reduce the accumulation of homocysteine in the body A low methionine diet must be combined with a drug called betaine, which converts homocysteine to methionine This further reduces the accumulation of homocysteine, allowing methionine to be incorporated into the body's protein reserves The drug constantly converts a small amount of homocysteine into methionine, but does not maintain a rapid pace of homocysteine production, so it must be combined with a low methionine diet The drug, along with diet, prevents toxic levels of homocysteine build-up and the development of disease symptoms.