RENAL GLYCOSURIA - A CASE REPORT

Renal glycosuria is the excretion of glucose in the urine in detectable amounts at normal blood glucose concentrations in the absence of any signs of generalized proximal renal tubular dysfunction SGLT2 is a low-affinity sodium - glucose co transporter responsible for the bulk of tubular reabsorption of filtered glucose SGLT2 gene also referred to as SLC5A2 coding sodium -glucose transporter type 2 protein localized to chromosome 6, Mutations in the gene for SGLT2 is seen with familial renal glycosuria (FRG), Glycosuria in these patients can range from 1to 150 g per 1.73 m2 per day. Karthick, a 9 years old boy born of 3rd degree consanguinous marriage came to the paediatric department with the complaint of fever for 2 days, no history of polyuria, during routine investigation urinalysis was done by dipstick method shows pH- 6.3,sugar- 3 plus, protein - nil .We used siemens reagent strip for urinalysis, which use GOD-POD method for glucose detection, this method is specific only for glucose and do not show other urinary sugars. Physical examination of the boy was normal.The fasting blood glucose was done which is 79mg per dl. OGTT shows normal blood glucose level with urine glucose positive in fasting, 60 minutes and 120 minutes sample. HbA1c was normal. Proximal tubular dysfunction was ruled out by normal level of excretion of sodium, phosphate, uric acid and aminoaciduria was ruled out with thin layer chromatography of urine sample compared with age matched control sample and amino acid standard. Urinalysis performed in the boys mother urine was negative for glucose and protein. Benign renal glycosuria is a self-limiting disease which is mostly asymptomatic and has a good prognosis in which medical treatment or diet limitation is not required. They can normally store and utilize glucose. The clinical and biochemical diagnosis of this case is Benign renal glycosuria, further mutational analysis of the gene coding for the transporter is needed to confirm the type of mutation.