Ketone body formation without glycosuria seen in:

C i.e. Prolonged StarvationHexokinase has low Km value i.e. high affinity for glucoseQ and it is present in all tissue including brain0; where as glucokinase has high Km value i.e. low affinity for glucoseQ and it is present in liver and BcellsQ. That's why brain can utilize glucose in starvation but the liver can not. The glucokinase functions only when intracellular concentration of glucose in hepatocytes is elevated as in post absorptive state.