Synonym

• Glucose (Urine)
• Ketones (Urine)
• Dipstick Glucose (Urine)
• Dipstick Ketones (Urine)

Tubes

• 10-20 mL urine in a disposable sterile plastic container or plain tube
• Midstream random urine sample to be collected

Additional information

• Use a freshly voided specimen
• Send specimen to lab immediately
• If delay of >1hr is expected, refrigerate the specimen
• Attention should be given to avoid having skin epithelium, secretions, hair, lint, etc from contaminating the sample
• Avoid preservatives or any other contamination
• Instructions for clean catch midstream urine collection:
• For male
• Wash hands thoroughly
• Cleanse the meatus
• Void a small amount into the toilet
• Then, void directly into the specimen container
• For female
• Wash hands thoroughly
• Cleanse the labia from front to back
• While keeping the labia separated, void a small amount into the toilet
• Without interrupting the urine stream, void directly into the specimen container

Info

This test detects the presence of glucose and ketones in the urine.

• Glucose:
• Detected by dipstick testing when serum glucose is sufficiently elevated such that some glucose makes it into the urine [normally some glucose will be present in the urine when the serum glucose has been >180 mg/dl (10 mmol/L)]
• This test is based on the enzymatic color change of glucose oxidase
• Very sensitive and specific test
• Except for glucose, other sugars in the urine will not give a positive result
• Ketones:
• This test measures ketones in the urine, including acetone, and acetoacetic acid
• -hydroxybutyrate is not detected by reagent strip method
• Ketones are formed from the metabolism of fatty acids/fats
• In normal persons, ketones are formed in the liver and completely metabolized, and thus not detected in the urine. However, when carbohydrate metabolism is altered, an excessive amount of ketones is formed (acidosis) as fat becomes the predominant body fuel instead of carbohydrates

Clinical

The clinical utility of urinalysis for presence of glucose and ketones includes the following:

• As a basic screening test to evaluate the overall health of the patient during general physical examination, as on admission to a healthcare facility
• As general screening for glucose and ketone bodies done in:
• Hospitalized patients
• Presurgical patients
• Pregnant women
• Children
• Persons with diabetes
• To monitor glycosuric patients in the following conditions:
• Patients showing elevated urine and blood glucose
• When treatment is being switched from insulin to oral hypoglycemic agents (the development of ketonuria within 24 hrs after withdrawal of insulin usually indicates a poor response to the oral hypoglycemic agents)
• Diabetic patients treated with oral hypoglycemic agents
• To judge the severity of acidosis and to monitor the response to treatment
• Results are obtained by noting the presence of a visible color change on the test pad of the dipstick. A color scale will indicate the result, either in an estimated quantitative value (for example: 250 mg/dl, 1000 mg/dl), or a descriptive term (for example, negative, trace, small, or large)

Glucose

• The renal threshold where filtered blood glucose can no longer be fully resorbed varies between individuals; but is typically ~ 180 mg/dL (10 mmol/L)
• The renal threshold may increase or decrease in various physiological conditions
• In pregnancy, the renal threshold decreases
• Patients with significant glycosuria have increased urine specific gravity due to increased glucose in the urine
• The advantage of the dipstick test is that it is not affected by other reducing substances in the urine

Ketones

• Ketosis and ketonuria may occur whenever increased amounts of fat are metabolized, carbohydrate intake is restricted, or the diet is rich in fats
• Urine ketone dipstick testing provides a rapid, inexpensive, and reliable indicator of acidosis
• Early detection of urinary ketones in pregnancy is useful in evaluating for ketoacidosis (both with diabetics and with hyperemesis gravidarum)
• This test measures ketones in the urine, including acetone, and acetoacetic acid
• -hydroxybutyrate is not detected by reagent strip method
• Some laboratories recommend direct measurement of serum ketones instead of the urine dipstick analysis (due to some patients in diabetic ketoacidosis having primarily ß-hydroxybutyrate)
• Ketonuria does not reflect renal dysfunction. It is caused by endocrine and metabolic disorders
• Staging of ketonuria:
• Small: <20 mg/dL
• Moderate: 30 to 40 mg/dL
• Large: >80 mg/dL
• Diabetic ketoacidosis may clinically manifest as:
• Acetone smell (fruity) on the breath
• Abdominal pain (30%)
• Coma
• Dehydration
• Hypothermia
• Kussmaul's breathing
• Mental clouding or confusion
• Nausea and vomiting (50-80% of cases)
• Tachycardia and hypotension
• Tachypnea
• Weakness and lethargy

Related laboratory tests include:

• Blood and urine creatinine
• Blood and urine electrolytes
• Blood and urine protein
• Blood and urine urea nitrogen
• Blood glucose
• Blood ketones
• Complete blood count
• Glycolated hemoglobin
• Hemoglobin A1C
• Urine culture
• Urine osmolality

Nl Result

Consult your laboratory for their normal ranges as these may vary somewhat from the ones listed below.

• Glucose (sugar): negative or none
• Ketones (acetone): negative or none

The detectable ranges by the dipsticks reagent strips are:

Glucose

• Positive detectable range: 75–300mg/dL
• Lowest Detectable Range 75–125 mg/dL
• Trace = 100 mg/dL
• 1/4 = 250 mg/dL
• 1/2 = 500 mg/dL
• 1 = 1000 mg/dL
• 2 = 2000 mg/dL

Ketones

• Positive detectable range: 5 to 10mg/dL
• Trace = 5 mg/dL
• Small = 15 mg/dL
• Moderate = 40 mg/dL
• Large = 80–160 mg/dL

High Result

Glucose

Conditions associated with elevated levels of glucose (glucosuria) in urine include:

• Diabetes mellitus (Type 1 or 2)
• Benign renal glucosuria – Type A, B and O
• Pathological renal glucosuria
• Fanconi syndrome
• Heavy metal poisoning (Lead or mercury)
• Hereditary tyrosinemia
• Interstitial nephritis
• Lowe syndrome (oculocerebrorenal dystrophy)
• Pregnancy
• Wilson's disease
• Other endocrine disorders
• Acromegaly
• Cushing's syndrome
• Hyperadrenocorticism
• Hyperthyroidism
• Pheochromocytoma
• Pancreatic disorders
• Carcinoma of the pancreas
• Hemochromatosis
• Pancreatitis
• Liver disease
• Central nervous system disorders
• Brain injury
• Stroke
• Myocardial infarction
• Others
• IV fluids containing glucose
• Total parenteral nutrition (TPN) containing 10–50% glucose
• Burns
• Fractures
• General anesthesia (post anesthesia)
• Glycogen storage diseases
• Head injury
• Infections
• Obesity
• Postprandial (from large meal)
• Pregnancy
• Stomach resection
• Stress/Excitement
• Traumatic injuries
• Uremia
• Drugs and substances
• Acetazolamide
• ACTH
• Aminosalicylic acid
• Ampicillin
• Ascorbic acid
• Asparaginase
• Aspirin
• Azlocillin
• Benzthiazide
• Bismuth subsalicylate
• Bupropion
• Captopril
• Carbamazepine
• Carbenicillin
• Carvedilol
• Cefaclor
• Cefamandole
• Cefazolin
• Cefdinir
• Cefepime
• Cefixime
• Cefoperazone
• Cefuroxime
• Cephalexin
• Cephalosporins
• Chlorothiazide
• Chlorpromazine
• Chlorthalidone
• Chloral hydrate
• Chloramphenicol
• Cidofovir
• Corticosteroids
• Corticotropin
• Dexamethasone
• Dextroamphetamine
• Dextrothyroxine
• Diazoxide
• Diuretics (loop and thiazides)
• Doxorubicin
• Enalapril
• Ephedrine
• Estrogens
• Ethacrynic acid
• Ether
• Ethionamide
• Etretinate
• Fludrocortisone
• Foscarnet
• Furazolidone
• Furosemide
• Gabapentin
• Histrelin
• Hydrochlorothiazide
• Ifosfamide
• Indomethacin
• Isoniazid
• Lansoprazole
• Levodopa
• Lisinopril
• Lithium
• Methyclothiazide
• Metolazone
• Mirtazapine
• Misoprostol
• Morphine
• Nalidixic acid
• Nafcillin
• Naproxen
• Niacin
• Nicotinic acid (large doses)
• Nitrofurantoin
• Norfloxacin
• Octreotide
• Ofloxacin
• Oral contraceptives
• Penicillin
• Perphenazine
• Phenazopyridine
• Phenothiazines
• Phenytoin
• Piperacillin
• Polythiazide
• Probenecid
• Quinethazone
• Reserpine
• Ritodrine
• Sevoflurane
• Somatropin
• Streptozocin
• Strychnine
• Sulfonamides
• Tacrine
• Tetracycline (old)
• Theophylline
• Thiazides
• Thiothixene
• Ticarcillin
• Timolol
• Triamcinolone
• Venlafaxine

Ketones

Conditions associated with elevated levels of ketones in the urine include:

• Metabolic conditions
• Diabetes mellitus (diabetic acidosis)
• Renal glycosuria
• Glycogen storage disease (von Gierke's disease)
• Non diabetic ketonuria
• Acute febrile illnesses in children
• Alcoholism
• Anorexia
• Diarrhea
• Eclampsia
• Fasting
• High-fat diets
• High-protein diets
• Hyperemesis gravidarum
• Low-carbohydrate diet or weight reducing diets
• Postanesthesia period - ether or chloroform
• Prolonged vomiting
• Severe stress
• Starvation
• Strenuous exercise
• Increased metabolic states
• Fever
• Hyperthyroidism
• Pregnancy or lactation
• Drugs
• Aminosalicylic acid
• Cefdinir
• Cefixime
• Dimercaprol
• Etodolac
• Ifosfamide
• Isoniazid
• Isopropanol intoxication
• Isopropyl alcohol
• Methyldopa
• Niacin
• Olanzapine
• Paraldehyde
• Phenylketones
• Phthaleins
• Streptozocin

False Positive results for dipstick enzyme tests, include:

• Peroxide or strong oxidizing agents
• Contamination of the collection container or specimen with chlorine, sodium hypochlorite, or peroxide
• Large amount of ketones body levels 50 mg/dL (for glucose)
• Highly pigmented urines (for ketones)
• Acidic urine (for ketones)
• Elevated specific gravity (for ketones) This may occur despite the fact that dehydration may impair renal excretion of ketones
• Drugs that cause false positive ketonuria include:
• 2-Mercaptoethane sulphonate sodium (MESNA)
• Ascorbic acid in very large doses
• Captopril
• Ether
• Insulin
• Levodopa
• Metformin
• N-acetyl cysteine
• Penicillamine
• Phenazopyridine
• Phenolphthalein
• Phenothiazine
• Sulfobromophthalein
• Valproate

Low Result

Glucose

Normally, no glucose is detected in the urine.

Drugs, which may decrease elevated urine glucose levels, include:

• Acarbose
• Ampicillin
• Aspirin
• Bisacodyl
• Chloral hydrate
• Cholestyramine
• Diazepam
• Digoxin
• Ferrous sulfate
• Flurazepam
• Furosemide
• Hydroquinone
• Insulin
• Levodopa
• Oxytetracycline
• Phenazopyridine
• Phenobarbital
• Radiographic agents
• Secobarbital
• Tetracycline
• Vitamin preparations

False negative results for glucose dipstick enzyme tests, include:

• Ascorbic acid (vitamin C) concentrations 50 mg/dL
• Rapid glycolysis of glucose occurs in urine if left at room temperature for an extended period
• Elevated specific gravity
• Increased uric acid

Ketones

Normally no ketones are excreted in the urine.

Drugs, which may decrease elevated urine ketone levels include:

• Aspirin
• Phenazopyridine

False-negative results are seen in the following conditions:

• If urine stands too long, owing to loss of ketones into the air
• In diabetic ketoacidosis (DKA) the predominant ketone may be ß-hydroxybutyric acid, which is not detected by the dipstick test

References

• Bhuling KJ et al. The usefulness of glycosuria and the influence of maternal blood pressure in screening for gestational diabetes. Eur J Obstet Gynecol Reprod Biol. 2004 Apr 15;113(2):145-8.
• eMedicine from WebMD®. Diabetic Ketoacidosis. [Homepage on the Internet] ©1996-2006. Last updated on June 22, 2006. Last accessed on November 30, 2006. Available at URL: http://www.emedicine.com/EMERG/topic135.htm
• eMedicine from WebMD®. Renal Glucosuria. [Homepage on the Internet] ©1996-2006. Last updated on May 8, 2006. Last accessed on November 30, 2006. Available at URL: http://www.emedicine.com/ped/topic1991.htm
• LabTestsOnline®. Urinalysis. [Homepage on the Internet] ©2001-2006. Last reviewed on May 9, 2005. Last accessed on November 20, 2006. Available at URL: http://www.labtestsonline.org/understanding/analytes/urinalysis/ui_exams-2.html
• Laffel LM et al. Sick day management using blood 3-hydroxybutyrate (3-OHB) compared with urine ketone monitoring reduces hospital visits in young people with T1DM: a randomized clinical trial. Diabet Med. 2006 Mar;23(3):278-84.
• MedlinePlus Medical Encyclopedia®. Ketones - Urine.[Homepage on the Internet]©2005. Last updated on December 9, 2005. Last accessed on November 20, 2006. Available at URL: http://www.nlm.nih.gov/medlineplus/ency/article/003585.htm
• Simerville JA et al. Urinalysis: A Comprehensive Review. Am Fam Physician. 2005 Mar 15;71(6):1153-62.
• Taboulet P et al. Urinary acetoacetate or capillary beta-hydroxybutyrate for the diagnosis of ketoacidosis in the Emergency Department setting. Eur J Emerg Med. 2004 Oct;11(5):251-8.
• UTMB Laboratory Survival Guide®. URINALYSIS (Chemistry and Microscopic). [Homepage on the Internet]© 2006. Last reviewed on February 2006. Last accessed on November 22, 2006. Available at URL: http://www.utmb.edu/lsg/LabSurvivalGuide/chem/URINALYSIS.html