Renal glucosuria is glucose in the urine without hyperglycemia; it results from either an acquired or an inherited, isolated defect in glucose transport or occurs with other renal tubule disorders.
Renal glucosuria is the excretion of glucose in the urine in the presence of normal plasma glucose levels.
Renal glucosuria can be inherited. This form usually involves a reduction in the glucose transport maximum (the maximum rate at which glucose can be resorbed) and subsequent escape of glucose in the urine. The inherited disorder is usually transmitted as an incompletely recessive trait (heterozygotes have modest glucosuria).
Renal glucosuria may occur without any other abnormalities of renal function or as part of a generalized defect in proximal tubule function (Fanconi syndrome). It also may occur with various systemic disorders, including cystinosis, Wilson disease, hereditary tyrosinemia, and oculocerebrorenal syndrome (Lowe syndrome).
Symptoms and Signs of Renal Glucosuria
Renal glucosuria is asymptomatic and without serious sequelae. However, if there is an associated generalized defect in proximal tubular function, symptoms and signs may include hypophosphatemic rickets, volume depletion, short stature, muscle hypotonia, and ocular changes of cataracts or glaucoma (oculocerebrorenal syndrome) or Kayser-Fleischer rings (Wilson disease). With such findings, transport defects other than glucosuria should be sought.
Diagnosis of Renal Glucosuria
Urinalysis
The disorder is typically initially noted on routine urinalysis, and is defined as glucosuria in the absence of hyperglycemia (serum glucose <140 mg/dL).
Some experts require a normal result on an oral glucose tolerance test for the diagnosis.
Treatment of Renal Glucosuria
No treatment needed
Isolated renal glucosuria is benign; no treatment is necessary.
