used for the analysis. Carbohydrate disorders Glucose - Identified as Glycosuria Ketones - Identified as Ketonuria (also see ketoacidosis and ketosis) Around 30–40% of type I diabetics and around 20% of type II diabetics suffer in time from a nephropathy, and early recognition of diabetes is therefore of major significance for the further state of health of these patients. Specific carbohydrate metabolism disorders able to be identified include Diabetes Mellitus, Glucosuria and Ketonuria. Glucose test Under normal conditions nearly all the glucose removed in the glomerulus is reabsorbed in the proximal convoluted tubule. If the blood glucose level increases, as happens in diabetes mellitus, the capacity of the convoluted tubule to reabsorb glucose is exceeded (an effect known as renal reabsorption threshold). For glucose this threshold is between 160–180 mg/dL. Glucose concentrations vary in an individual, and a healthy person can present with transitory glucosuria after a meal high in sugars; therefore the most representative results come from samples obtained at least two hours after food is eaten. The detection of glucose by test strips is based on the enzymatic reaction of glucose oxidase. This enzyme catalyses the oxidation of glucose by atmospheric oxygen to form gluconic acid and hydrogen peroxide. A second linked reaction, mediated by a peroxidase, catalyses the reaction between the peroxide and a chromogen (a substance that acquires colour after a chemical reaction) to form a coloured compound that indicates the glucose concentration. 1) Catalysed by glucose oxidase Glucose + O2 → D-glucono-δ-lactone + H2O2 2) Catalysed by peroxidase H2O2 + Chromogen → Oxidised chromogen (coloured) + H2O The reaction is specific for glucose, as occurs in all enzymatic reactions, but it can provide some false positive results due to the presence of traces of strong oxidising agents or peroxide from disinfectants used on laboratory instruments. Ketone test The term ketones or ketone bodies in reality refers to three intermediate products in the metabolism of fatty acids; acetone, acetoacetic acid and beta-hydroxybutyric acid. Elevated concentrations of ketones are not generally found in urine, as all these substances are completely metabolized, producing energy, carbon dioxide and water. However, the disruption of carbohydrate metabolism can lead to metabolic imbalances and the appearance of ketones as a by-product of the metabolism of an organism's fat reserves. An increase in fat metabolism can be the result of starvation or malabsorption, the inability to metabolize carbohydrates (as occurs, for example, in