Renal Glucosuria

Renal glucosuria . Etiology, pathogenesis. Renal glucosuria develops as a result of a hereditary defect in the renal tubular enzyme systems that provide glucose reabsorption. About renal gljukozurii it is necessary to speak in those cases when the release of glucose with urine exceeds the level of physiological excretion (200 mg / day). In renal glucosuria, the daily excretion of glucose in urine is usually 10-20 g, although there are cases of glucosuria reaching 100 g. The frequency of renal glucosuria is 2-3: 1000; Type of inheritance is autosomal dominant.

Clinical picture. Clinical symptoms (except for glucosuria) are observed mainly in very severe cases and are caused by significant sugar losses. Patients experience weakness, hunger. Persistent osmotic diuresis (polyuria) is the cause of dehydration and hypokalemia. With a deficiency of carbohydrates may be associated with a delay in the physical development of the child.

Diagnosis. The criteria for renal glucosuria are:

1) increased glucose excretion with normal blood sugar; 2) the independence of the excretion of glucose in the urine from the intake of carbohydrates; Excretion of glucose is relatively constant both in the daytime and at night; 3) the absence of changes in the level of sugar in the blood when carbohydrates enter; 4) identification of sugar, excreted in urine, as glucose; 5) normal sugar curve after loading with glucose.

In addition to diabetes mellitus, in the differential diagnosis of renal glucosuria, it is necessary to keep in mind melilities of a different nature, in particular, melilia in acute tubular necrosis, toxic kidney damage, steroid diabetes with the use of glucocorticoids for therapeutic purposes, fructosuria, pentosuria. Positive samples for sugar in urine can be detected with benign fructosuria. The absence of other clinical signs in these cases can lead to the conclusion about the possibility of renal glucosuria. It is necessary to identify the carbohydrates that are excreted in the urine.

It should also be borne in mind the complex syndromes in which renal glucosuria manifests as a particular symptom: gluco-aminophosphate-diabetes, gluco-amino-diabetes, gluco-phosphate-diabetes. This circumstance requires a compulsory study of the excretion of phosphates and amino acids in each patient with renal glucosuria.

Treatment. Methods of pathogenetic therapy of this disease does not exist. It is important to ensure proper nutrition of the patient, in order to avoid overloading with carbohydrates and hyperglycemia, which contributes to the increase in sugar losses. With the development of hypoglycemia, there may be a need for additional administration of glucose, and with hypokalemia, it is advisable to administer products containing large amounts of potassium (raisins, carrots, etc.).

The prognosis is favorable.

Prevention: medical genetic counseling.