Prognosis vs. life expectancy in phenylketonuria
The life expectancy of the affected persons depends on the one hand on the present form of phenylketonuria and on the other hand on the time when the disease is diagnosed. While a normal life expectancy is possible with a normal variant of phenylketonuria, there are rare variants of the disease, which for example are associated with a significantly increased cramping potential, which as a consequence can have a more frequent fatal outcome. In the normal variant of phenylketonuria, on the other hand, the age of the patient is only slightly affected at most. However, the time of diagnosis and the start of treatment determine the extent of the mental impairment of the patient. Thus, mental intelligence has a maximum indirect effect on life expectancy.
Disease course of phenylketonuria
The course of the disease also varies, even more so than life expectancy, depending on the form of the disease and the time of diagnosis or treatment. If the disease is diagnosed in newborn screening or U2 and the low-phenylalanine diet is strictly adhered to, as well as any substitution that may be necessary, the disease virtually never appears. In addition, people with residual activity of the affected enzyme are at an advantage, as the disease is mild in the worst case.
However, if the diagnosis is delayed, irreversible mental impairment is to be expected, which will continue for the rest of your life. Nevertheless, phenylketonuria is not a disease that causes premature death in Western countries, but rather a normal life expectancy. A complete cure from the disease is not possible because it is a hereditary disease.
The maximum therapy consists of a low-phenylalanine diet, which results in a reduction of symptoms.If the disease is diagnosed and treated early, there is hardly any abnormality; however, the peculiar smell of urine and the cytotoxic effect of too high phenylalanine levels occur again and again as soon as the diet is abandoned. However, since the disease is inherited recessively, it is rather unlikely that the disease will be passed on.
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