Fructosuria
As fructosuria or fructosuria refers to the increased excretion of fructose ( fructose ) in the urine by the kidney. The cause is an accumulation of fructose in the blood , the fructosemia, because not enough fructose is broken down in the body.
Types of pathogenesis (formation)
A distinction is made between two different types of fructosuria:
The essential fructosuria can be traced back to a genetic defect . This leads to a loss of activity of the enzyme fructokinase in the liver and thus to fructosemia , i.e. an accumulation of fructose in the blood. This is normally excreted in the urine as a result of the blood filtering in the kidneys. The metabolic disorder is harmless and does not require treatment.
The hereditary fructose intolerance against it is a serious disorder of fructose metabolism. Affected exhibit a lack of or loss of activity of the enzyme fructose-1-phosphate Adolase B on. As a result of this disorder, the fructose cannot be broken down or only insufficiently. This leads to fructosemia . In addition, uric acid production is increased ( hyperuricemia ) and the formation of glucose is disturbed - acidosis (over-acidification) and hypoglycemia (low blood sugar) are the consequences. If those affected do not forego fructose in their diet, the kidneys and liver in particular are severely damaged. If a strict diet is not followed, the organ damage continues to increase until there is finally liver dysfunction - jaundice ( jaundice ), edema , coagulation disorders - and increased proteinuria (increased excretion of protein in the urine) as a result of kidney damage . The treatment of hereditary fructose intolerance is a fructose, sucrose and sorbitol-free diet (avoidance of fructose , cane sugar and sorbitol ).
literature
- Günther Malyoth, Karl Scheppe, Hans Walther Stein: Fructosuria, Pentosuria, Mannosuria: About a rare familial disorder of the carbohydrate metabolism. In: Clinical weekly. November 1952, Vol. 30, Nos. 43-44, pp. 1018-1020.
- A. Rosary: Fructose metabolism in essential fructosuria. In: Clinical weekly. November 1960, Vol. 38, No. 21, pp. 1090-1093.