MELITURIA (melituria; grech, meli, melit[os] honey + uron wetting) — the raised excretion with urine of various sugars. Meets more often at children's age.
More than 10 types of sugars are excreted with urine and at healthy people in trace quantities (glucose, lactose, fructose, sucrose, a maltose, a ribose, etc.). At newborns in the first days of life it is noted fiziol. The m, edges is shown by the raised daily excretion with urine lactoses (see) — to 120 mg, fructose — 70 mg, galactoses (see) — 25 mg, glucose (see) — 25 mg. At premature children also higher rates can be noted. At children of early age are also noted fiziol. M of alimentary character after consumption of jam, honey, fruit juice. Fast-passing fiziol. The m of an alimentary origin can be observed also at healthy adults after consumption of the products containing a large amount of this or that sugar.
Depending on a type of the sugar defined in urine the following types M. can be allocated: glycosuria (see), lactosuria (see), fruktozuriya (see), maltosuria, sakharozuriya, galaktozuriya, mannozuriya, pentosuria (see), etc., and also M. of the mixed type when with urine several sugars are emitted.
The m can be caused by tubulopatiya, at to-rykh processes of transport of carbohydrates in proximal department of nephron are broken (see. Tubulopatiya hereditary ), at the same time metabolic defect or is localized in the nephron, or not connected with it. At localization of defect in nephron M. most often develops owing to enzymopathies (see) — insufficiency of the enzymes providing membrane transport of carbohydrates in tubules of kidneys. Disturbances of structure of membranes or membrane proteins carriers, decrease in sensitivity of receptors of a canalicular epithelium to effect of hormones can be more rare reasons. As a result the reabsorption of this or that carbohydrate in proximal department of nephron is in whole or in part blocked. In blood the content of carbohydrates remains close to normal indicators. A classical example of M. of this kind is the so-called renal glycosuria.
At localization of metabolic defect out of nephron M. arises, as a rule, at a number of the hereditary and acquired disbolism. At the same time too large amount of these or those sugars exceeding a threshold of a reabsorption, equal 160 — 200 mg of % comes to urine from blood. Emergence in urine of lactose, sucrose and a maltose is observed at intolerance by their organism of the patient and is caused by insufficient splitting of these disaccharides in intestines (see. Malabsorption syndrome ). Disturbance of exchange in a liver of fructose or a galactose leads to a fruktozuriya or a galaktozuriya. The same changes can be observed at diseases went. - kish. a path, a liver, pancreatitis, a diabetes mellitus, and also at intoxications, poisonings, inflammatory diseases of kidneys. Such diseases, as Gee's disease (see), pylorospasm (see), and also vomiting of various genesis, often lead to secondary disturbance of exchange of sugars and to M.
At M. treatment of a basic disease is carried out.
Bibliography: Badalyan K. Lake, Tabolin V. A. and Veltishchev Yu. E. Hereditary diseases at children, M., 1971; Rachev D., Todorov Y. and State-v and St. A metabolism at children's age, the lane with bolg., Sofia, 1967; Metabolic endocrine, and genetic disorders of children, ed. by V. Ch. Kelley, v. 1 — 3, Hagerstown, 1974.
Yu. A. Knyazev, V. P. Lebedev.