Metabolic Acidosis

Definition

Metabolic acidosis is a condition in which there is too much acid in the body fluids.

Alternative Names

Acidosis - metabolic

Causes

Metabolic acidosis occurs when the body produces too much acid, or when the kidneys are not removing enough acid from the body. There are several types of metablic acidosis:

• Diabetic acidosis (also called diabetic ketoacidosis and DKA) develops when substances known as ketone bodies, which are acidic, build up during uncontrolled diabetes
• Hyperchloremic acidosis results from excessive loss of sodium bicarbonate from the body, as can happen with severe diarrhea
• Lactic acidosis is a buildup of lactic acid. It can be caused by:
  • Alcohol
  • Cancer
  • Exercising for a very long time
  • Liver failure
  • Low blood sugar (hypoglycemia)
  • Medications such as salicylates
  • Prolonged lack of oxygen from shock, heart failure, or severe anemia
  • Seizures

Other causes of metabolic acidosis include:

• Kidney disease (distal tubular acidosis and proximal renal tubular acidosis)
• Poisoning by aspirin, ethylene glycol (found in antifreeze), or methanol
• Severe dehydration

Symptoms

Most symptoms are caused by the underlying disease or condition that is causing the metabolic acidosis. Metabolic acidosis itself usually causes rapid breathing. Confusion or lethargy may also occur. Severe metabolic acidosis can lead to shock or death. In some situations, metabolic acidosis can be a mild, chronic (ongoing) condition.

Exams and Tests

• Arterial blood gas
• Serum electrolytes
• Urine pH

Arterial blood gas analysis or a serum electrolytes test (such as a basic metabolic panel) will confirm acidosis is present and determine whether it is respiratory acidosis or metabolic acidosis.
Other test may be needed to determine the cause of the acidosis.

Treatment

Treatment is aimed at the underlying condition. In certain circumstances, sodium bicarbonate (baking soda) may be given to improve the acidity of the blood.

Outlook (Prognosis)

What can be expected will depend on the underlying disease causing the metabolic acidosis.

Possible Complications

When very severe, metabolic acidosis can lead to shock or death.

When to Contact a Medical Professional

Seek medical treatment if you develop symptoms of any disease that can cause metabolic acidosis.

Prevention

Keeping type 1 diabetes under control may help prevent diabetic ketoacidosis, one type of metabolic acidosis.

References

Seifter JL. Acid-base disorders. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 119.