Glycosuria Causes

The suspected causes of renal glycosuria can be that the level of blood glucose could get too high due to which the renal tubules cannot reabsorb it completely or, there might be failure of the tubules to reabsorb all the glucose. Thyrotoxicosis, Acromegaly, Cushing's syndrome, Rapid gastric emptying (dumping syndrome) and peptic ulcers, all these can raise blood glucose above the threshold. Stress hormones elevate blood glucose and in a severely ill patient they may even elevate glucose, beyond the renal threshold.

Secondary causes elevating urine sugar level (temporarily) are as stated below-

Pregnancy: During pregnancy there is increased renal blood flow, leading to lowered renal threshold
Oculocerebrorenal Dystrophy (Lowe syndrome)
Cystinosis
Wilson's disease
Interstitial nephrities
Hereditary tyrosinaemia
Heavy metal poisoning such as lead, mercury or with old tetracycline
Intestinal glucose-galactose malabsorption
Glycosuria occurs without significant pathology and is mainly bifurcated into 3 categories:-

Type A :- it is classical glycosuria, with decline in both, glucose threshold and maximal glucose reabsorption rate.
Type B :- There is a decline in the glucose threshold and a normal rate of reabsorption.
Type O :-There is failure of glucose reabsorption. Plasma glucose, glucose tolerance test, insulin levels and HbA1C, all are normal.
Mainly for the affected individuals, this condition causes no visible signs and symptoms or serious effects, but it is a marker for detecting the status of kidney and a diabetic.

Synonyms of glycosuria are listed below

Benign glycosuria
Familial renal glycosuria
Nondiabetic glycosuria
Primary renal glycosuria
Diabetes renalis
Renal diabetes