Practically on all chewing gums (Orbit, Stimorol...) there is an inscription “contraindicated for patients with a fenilketonuriya“. And what the illness such and why there is such contraindication is?“ .
For a start brief biochemical information. Phenylalanine belongs to irreplaceable amino acids (substances which go for creation of proteins in a human body) as tissues of animals are not capable to synthesize it. In a human body where phenylalanine gets with food, there is a process of its oxidation by means of specific enzyme of a fenilalaningidroksilaza to completely replaceable amino acid - a tirozin. Violation (blocking) of this reaction observed at violation of synthesis of a fenilalaningidroksilaza in a liver leads to development of a serious hereditary illness - a fenilketonuriya.
Tirozin is used by an organism for synthesis of hormones of a thyroid gland. And melanin, derivative a tirozin and phenylalanine, provides pigmentation (color coloring) of skin, an eye and a hair.Fenilketonuriya`s
is also called a fenilalaninemiy, fenilpirovinogradny oligofreniya. The disease belongs to congenital violations of a metabolism (metabolism), is characterized by increase of level of phenylalanine in plasma of blood and is followed by intellectual backwardness. The exact reason of intellectual backwardness at a fenilketonuriya is unknown, but it is a consequence of biochemical defect. Hereditary character of a disease is found in most of people. Frequency of occurrence of a fenilketonuriya in the USA makes about 1 on 16 000 newborns.
Clinical symptoms of a fenilketonuriya at newborns usually are absent therefore it is necessary to carry out laboratory screening (diagnostics) surely. Slackness and difficulties when feeding is in rare instances noted. At most of uncured patients the disease demonstrates this or that degree of intellectual backwardness (more often than expressed) which is the main symptom of a fenilketonuriya. Usually at patients lighter skin, hair and eyes, than at their healthy relatives. At some children the skin changes reminding infantile eczema can be noted.the plentiful neurologic symptomatology is characteristic
Of patients with a fenilketonuriya, especially changed there are reflexes. At children of more advanced age both big, and small epileptic seizures are noted, deviations on the electroencephalogram are noted in 75 - 90% of cases. The expressed increase of activity and psychoses develop, often from patients the unpleasant “mouse“ smell caused by availability of feniluksusny acid in urine and sweat proceeds.
Diagnostics. After the newborn received milk (a phenylalanine source) during, at least, 48 h, doctors carry out screening - the test for a fenilketonuriya (investigate a blood drop). 4 - 6 weeks a product of disintegration of phenylalanine are aged more senior it is possible to reveal in urine of the sick child. At this time carry out one more screening - the test for a fenilketonuriya. The uric test is carried out after the end of the period of a neonatality, and to children from families where is available a sick fenilketonuriya, it should be repeated regularly within the first year of life.
Treatment consists in restriction of intake of phenylalanine with food to satisfy need for this irreplaceable amino acid, but it is no more; to provide the normal growth and development, without allowing accumulation in an organism of phenylalanine and the final products of its exchange. Continuous supervision over phenylalanine level in the child`s blood is required. In the USA for replacement of milk the product lofenalak, full in every respect, containing a small amount of phenylalanine is widely used. The use of reduced-protein natural products, for example fruit, vegetables, some cereals etc. is allowed. The need for phenylalanine is satisfied due to consumption of limited amount of natural protein and residual amount of phenylalanine in a lofenalaka. Now on sale there are products which are completely cleared of phenylalanine. The product phenyl - fr contains all necessary ingredients except phenylalanine, does not contain fat therefore its power value is lower, than at other products.
Treatment at the doctor should be passed from the first days of life. Only early and consecutive treatment prevents defeat of the central nervous system and heavy intellectual backwardness. If treatment is begun after 2 - 3 years of life, with its help it is only possible to limit the expressed hyperactivity and to facilitate a current of a convulsive syndrome.