HealthFlex
×
  • Home
  • Immunology Book
  • Lab Tests
    • Hematology
    • Fluid analysis
    • CSF
    • Urine Analysis
    • Chemical pathology
    • Blood banking
    • Fungi
    • Immune system
    • Microbiology
    • Parasitology
    • Pathology
    • Tumor marker
    • Virology
    • Cytology
  • Lectures
    • Bacteriology
    • Liver
    • Lymph node
    • Mycology
    • Virology
  • Blog
    • Economics and technical
    • Fitness health
    • Mental health
    • Nutrition
    • Travel
    • Preventive health
    • Nature and photos
    • General topic
  • Medical Dictionary
  • About Us
  • Contact

Diabetes Mellitus:- Part 7 – Diabetic Ketoacidosis and Ketone Bodies

October 27, 2023Chemical pathologyLab Tests

Table of Contents

Toggle
  • Diabetic Ketoacidosis
        • What sample for Diabetic Ketoacidosis is needed?
        • What are the precautions for Diabetic Ketoacidosis?
        • How will you Define diabetic ketoacidosis?
      • Pathophysiology of Diabetic Ketoacidosis
      • What is the mechanism of ketone body production?
        • How will you define Ketonemia and ketonuria?
      • What are the Signs and Symptoms of diabetic ketoacidosis?
      • Procedure for ketone bodies:
        • Gerhardt’s ferric chloride:
        • The procedure of Gerhardt’s test:
        • Nitroprusside Method for ketone bodies:
        • Strip method:
        • Rothera’s test
        • Nitroprusside tube method:
        • What are the findings in diabetic ketoacidosis?
        • What are the complications of diabetic ketoacidosis?
        • How will you treat diabetic ketoacidosis?
      • Questions and answers:

Diabetic Ketoacidosis

What sample for Diabetic Ketoacidosis is needed?

  • The ketones can be detected in blood and urine.

What are the precautions for Diabetic Ketoacidosis?

  1. The false-positive test may be seen in some medications.
  2. Prolonged exposure of the strips to air gives a false-negative result.

How will you Define diabetic ketoacidosis?

  1. This is an acute life-threatening metabolic acidosis due to uncontrolled diabetes mellitus.
    1. It is mostly due to type 1 and less frequently by type 2.
    2. It is a decompensated stage of intercurrent illness and severe insulin deficiency.
    3. There is excess hormone-producing glucose.
  2. Normally, no ketones are present in the urine.
  3. Diabetic ketoacidosis is due to Ketone bodies in the blood and the urine.
  4. There is a presence of ketones in the blood, which are toxic acids.

Pathophysiology of Diabetic Ketoacidosis

  1. This is a complication in diabetic patients with hyperglycemia and massive fatty catabolism.
  2. The primary substrate for ketone body formation is free fatty acids from adipose tissue.
    1. This is due to the lack of insulin in uncontrolled diabetes mellitus.
    2. These free fatty acids are substrates for the formation of ketone bodies.
    3. When reesterified in the liver, these free fatty acids give rise to triglycerides and low-density lipoproteins.
Diabetic Ketoacidosis: Ketone bodies formation in diabetic patients

Diabetic Ketoacidosis: Ketone body formation in diabetic patients

  1. When the body can not utilize carbohydrates or glucose, it can not enter the cells.

What is the mechanism of ketone body production?

  1. Glucose provides energy to the body. During starvation or uncontrolled diabetes mellitus, the energy is supplied by the breakdown of fats.
    Diabetic Ketoacidosis: ketone bodies pathogenesis

    Diabetic Ketoacidosis: ketone body pathogenesis

  2. In the blood samples, mainly  78% is beta-hydroxybutyric acid, and acetone is hardly 2%.
Diabetic Ketoacidosis: Ketone bodies formation and their ratio

Diabetic Ketoacidosis: Ketone body formation and their ratio

  1. Ketones are formed when fats provide energy to the body.  The enzymes responsible for forming ketone bodies are present in the mitochondria.
    1. Acetyl-CoA from acetoacetyl-CoA by the β-oxidation.
    2. Acetoacetyl-CoA- CoA is the starting point of ketogenesis.
    3. Acetoacetate is formed from the acetoacetyl-CoA in the liver.
    4. In the extrahepatic tissue, acetoacetate is activated by acetoacetyl-CoA.
    5. Now acetoacetyl-CoA- CoA is split into acetyl-CoA by thiolase, is oxidized in the citric acid cycle, and produces CO2.
    6. In most cases of ketonemia, increased ketone bodies are formed in the liver and are not dependent upon the utilization of ketone bodies in the extrahepatic tissue.
Diabetic Ketoacidosis: Ketone bodies pathogenesis and extrahepatic tissue role

Diabetic Ketoacidosis: Ketone bodies pathogenesis and extrahepatic tissue role.

  1. Ketone bodies are:
    1. Acetoacetate.
    2. β-hydroxybutyrate.
    3. Acetones.
      ketone bodies

      Ketone bodies

  2. ketone bodies are the end product of fatty acid breakdown.
Diabetic Ketoacidosis: ketone bodies formation in the diabetic patient

Diabetic Ketoacidosis: Ketone bodies formation in the diabetic patient

  1. The presence of ketone bodies in the urine indicates poorly controlled diabetes mellitus.
Diabetic Ketoacidosis: ketone bodies ratio

Diabetic Ketoacidosis: Ketone bodies ratio

How will you define Ketonemia and ketonuria?

  1. It is called ketosis when the body can not utilize the ketone bodies produced in excess.
    1. These are excreted in the urine and are called ketonuria. There is the excretion of ketones more than traces.
    2. The elevated level of ketones in the blood is called ketonemia.
    3. This overproduction of keto acids leads to acidosis or lowers blood pH.
  2. Ketone bodies are toxic to the brain; if present in abundance in the blood, these will lead to coma.
  3. Diabetic ketoacidosis is life-threatening metabolic acidosis due to uncontrolled diabetes mellitus, usually seen in type 1 and less common in type 2.

What are the Signs and Symptoms of diabetic ketoacidosis?

  1. This condition is seen in carbohydrate deficiency, starvation, or frequent vomiting.
  2. The patient will have a thirst and a dry mouth.
  3. Increased frequency of urine.
  4. There is easy fatigue.
  5. There may be nausea, vomiting, and abdominal pain.
  6. There is a fruity odor breathe.
  7. Difficulty in concentration and confusion.
  8. This condition may become very serious if not treated in time.
  9. Ultimately patient may go into a coma.

Procedure for ketone bodies:

Gerhardt’s ferric chloride:

  1. It reacts with acetoacetate only.
  2. Principle of Gerhardt’s test:
    1. The reagent is 10% ferric chloride.
    2. It is based on the reaction of ferric chloride (FeCl3) with acetoacetic acid only, and it will form a red color.

The procedure of Gerhardt’s test:

  1. Take 3 to 5 mL of urine.
  2. Add 5 mL of Ferric chloride solution.
    1. Note the color, if it is red, indicates ketone body, acetoacetic acid.
  3. Now boil the above solution for 5 minutes.
    1. Color disappears, indicating acetoacetic acid. By boiling, acetoacetic acid changes to acetone by losing CO2.
    2. The color remains red, indicating the presence of salicylates.
Ketones ferric chloride test

Ketones ferric chloride test

Nitroprusside Method for ketone bodies:

  1. It is 10 times more sensitive to acetoacetate than acetone.

Strip method:

  1. Take urine (freshly voided sample) + add sodium nitroprusside (strips) = Deep violet color in positive cases.
    1.  It has no reaction to β-hydroxybutyrate.

Rothera’s test

  • It is the modification of the Nitroprusside method
Ketone test by Rothera's method

Ketone test by Rothera’s method

Nitroprusside tube method:

  1. Add 0.5 to 1.0 grams of nitroprusside to the bottom of the test tube, or can put it on porcelain tile.
  2. Add one drop of freshly voided urine. Sufficient to moisten the powder.
  3. Observe for one minute for the development of a mauve-purple color.
  4. It is easy to assess the color when testing in a test tube. Can see better against the white background.
Nitroprusside test for Ketones

Nitroprusside test for Ketones

Results are reported as follows:

Color change of the reagent Test result for ketones
No color change Ketones Negative
Slight purple color Ketones are +
Moderate purple color Ketones are ++
Dark purple color Ketones are +++
  1. For β-hydroxybutyrate, urine is heated to convert β-hydroxybutyrate to acetone and acetoacetate by oxidation.
    1. Commercial kits are available to estimate the β-hydroxybutyrate.
  2. Ketone bodies in the urine:
    1. The urine ketone bodies test detects acetoacetate and acetone.

What are the findings in diabetic ketoacidosis?

Lab test Result
  • Blood glucose
  • 300 to 500 mg/dL (250 to 600 mg/dL)
  • Ketones urine
  • Positive
  • Ketones serum
  1. Increased ++++
  2. Plasma acetone = positive in diluted plasma
  • Plasma acetone
  • Positive (in diluted plasma)
  • Acetone breath
  • Positive
  • Electrolytes
  1. Blood pH = <7.30
  2. Sodium = decreased (usually low) meq/L
  3. Potassium = increased or normal or low  meq/L
  4. The anion gap = increased (>12)
  5. pCO2 = decreased
  6. Serum HCO3 = <15 meq/L
  7. Serum phosphorus = Normal or increased
  8. Serum magnesium = Normal or increased
  • Blood gases
  • Total CO2 = decreased
  • Metabolic acidosis
  1. pH = <7.3
  2. Bicarbonate = decreased (<15 meq/L)
  • Osmolality
  • Moderately increased
  • Insulin (plasma)
  •  low to zero
  • Serum lactate
  • 2 to 3 mmol/L
  • Serum BUN
  • Lesser increase in mg/dL
  • Clinical presentation
  1. Age = usually younger
  2. Temperature = Normal or low
  3. Usually, type 1 diabetes mellitus
  4. Onset = Acute and subacute
  5. Predisposing factors = infections and unknown
  6. Acetone-like breath = Positive
  7. Kussmaul respiration = Present
  8. Abdominal pain = Present
  9. Changes in mental status = Moderate change
  10. Mortality = <10%
Diabetic ketoacidosis

Diabetic ketoacidosis

What are the complications of diabetic ketoacidosis?

  1. There is brain edema due to fluid accumulation.
  2. The patient may have a cardiac arrest.
  3. The patient may go into kidney failure.

How will you treat diabetic ketoacidosis?

  1. Start with saline for volume replacement.
  2. Insulin infusion (but delay if serum potassium level is low <_3.3 meq/L.
  3. Potassium replacement when the serum level is <5.5 meq/L.
  4. Glucose drip (5% dextrose with 0.45% saline when the plasma glucose level is <250 mg/dL).
  5. Continue glucose and insulin until the anion gap is <12 meq/L.

Questions and answers:

Question 1: What is Gerhardt's test?
Show answer
It reacts only with acetoacetate. This is a reaction with ferric chloride.
Question 2: What are complications of diabetic ketoacidosis?
Show answer
Cardiac arrest and kidney failure.
Question 3: What ketone bodies are detected in the urine?
Show answer
It detects acetoacetate and acetone.

Possible References Used
Go Back to Chemical pathology

Add Comment Cancel



The reCAPTCHA verification period has expired. Please reload the page.

  • Lab Tests
    • Blood banking
    • Chemical pathology
    • CSF
    • Cytology
    • Fluid analysis
    • Fungi
    • Hematology
    • Immune system
    • Microbiology
    • Parasitology
    • Pathology
    • Tumor marker
    • Urine Analysis
    • Virology

About Us

Labpedia.net is non-profit health information resource. All informations are useful for doctors, lab technicians, nurses, and paramedical staff. All the tests include details about the sampling, normal values, precautions, pathophysiology, and interpretation.

[email protected]

Quick Links

  • Blog
  • About Us
  • Contact
  • Disclaimer

Our Team

Professor Dr. Riaz Ahmad Bhutta

Dr. Naheed Afroz Syed

Dr. Asad Ahmad, M.D.

Dr. Shehpar Khan, M.D.

Copyright © 2014 - 2025. All Rights Reserved.
Web development by Farhan Ahmad.