Discussion of case history 2 (1) Mrs Bishop is justified in her concern, it is possible to inherit a predisposition to diabetes; in around a third of Type 2 diabetes cases there is a family history of the condition. Furthermore the presence of glucose in urine is a presenting feature of diabetes. The lack of symptoms is not an argument against the diagnosis. Many cases are discovered before symptoms develop, when blood or urine is tested for occupational or insurance health examinations. (2) However, the results of Mrs Bishop's glucose tolerance test a entirely normal (see Table 3.4) and the diagnosis can be excluded on the basis of these results. (3) Glycosuria, the presence of glucose in urine, usually only occurs when blood glu cose concentration is high and is therefore suggestive of diabetes. The renal threshold is the blood glucose concentration above which glucose is detectable in urine. Normally this is around 10-12mmol/L. For some people however, the renal threshold is signifi cantly lower and glucose may appear in urine at normal blood glucose concentration. Bishop is among this group The term 'renal glycosuria' is used to describe this entirely benign defect of kidney function. Although the finding of glucose in urine should never be ignored, it does not necessarily indicate diabetes.