Ketonuria is a medical condition in which ketone bodies are present in the urine.
Results from the production of ketone bodies as a normal response to a shortage of glucose, meant to provide an alternate source of fuel from fatty acids.
Seen in conditions in which the body produces excess ketones as an alternative source of energy.
Most commonly seen in type I diabetes mellitus.
Seen during starvation.
Ketones are formed in the liver and are completely metabolized, asw a result only negligible amounts appear in the urine.
When carbohydrates are unavailable or unable to be used as an energy source,
When fat becomes the predominant body fuel instead of carbohydrates excessive amounts of ketones are formed as a metabolic byproduct.
Elevated levels of ketones in the urine indicate that the body is using fat as the major source of energy.
Ketone bodies in the urine are acetoacetate and beta-hydroxybutyric acid, and acetone is produced and is expired by the lungs.
Acetone can be tested by a dipstick testing with small, moderate, or large amounts being positive.
Testing for ketonuria is done frequently for acutely ill patients, presurgical patients, and pregnant women, and diabetic patients with an elevated blood and urine glucose.
The development of ketonuria within 24 hours after insulin withdrawal usually indicates a poor response to the oral hypoglycemic agents.
Urinary ketones are tested to assess the severity of acidosis and to monitor treatment response.
Ketonuria occurs before there is any significant increase in blood ketones and is helpful in emergency situations.
During pregnancy, detection of ketonuria may indicate ketoacidosis a factor associated with intrauterine death.
Causes of ketosis and ketonuria include: diabetes, renal glycosuria, glycogen storage disease, starvation, fasting, high protein, or low carbohydrate diets, prolonged vomiting, hyperthyroidism, fever, pregnancy or lactation, acute illness or severe stress.
Approximately 15% of hospitalized patients may have ketonuria.
In a diabetic patient suggests that the patient is not adequately controlled, and in the nondiabetic patient, reflects a reduced carbohydrate metabolism and an increased fat metabolism.
Persistent ketonuria indicates a daily carbohydrate intake of less than 100 gm.