A dialysis machine having a haemodialysis filter; an inlet branch carrying a dialysis solution to the filter; an outlet branch carrying the dialysis solution from the filter; an artery line carrying blood from a patient to the filter; a vein line carrying blood from the filter to the patient; a number of pumps for circulating both the blood and the dialysis solution; and a glucose concentration measuring device fitted to a circuit portion in which a solution containing the dialysis- treated blood, or components of it, circulates.