Which of the following is the most probable diagnosis in a 35 years old man whose fasting and his post prandial blood sugar are within normal limits but urine sugar is three plus (+++)?

Renal Glycosuria Exp. D/D of glycosuria: * When glycosuria is found, it should be determined whether it is secondary to hyperglycemia (DM) or renal glycosuria. Glycosuria occurs when blood glucose level exceeds the renal glucose threshold threshold of 180 mg/ dl. * Nondiabetic melituria occurs in a number of conditions, the most impoant being renal glycosuria and alimentary (lag storage)glycosuria. Renal glycosuria- diagnosis is based on the marbel's criteria. * Glycosuria in the absence of hypeeglycemia * Constant glycosuria with little fluctuation related to diet * Normal oral glucose tolerance test * Identification of urinary reducing substance as glucose * Normal storage and utilization of carbohydrates Alimentary (lag storage) glycosuria: Here there is a transient abnormal rise in blood glucose level following a meal, and the concentration exceeds the normal renal threshold. During this time, gloucose spills into the urine. This may occur in the following conditions: * Following gastric surgery with rapid gastric emptying time * Same normal people * Hypehyroidism * Hepatic diseases