• Associations:  Acute ingestion +/- liver damage (rising AST/ALT) +/- metabolic acidosis

• Pathophysiology:  Acetaminophen metabolite, oxoproline and pyroglutamic acid.

• Associations:  History of alcohol abuse + normal glucose + ketones in urine

• Pathophysiology:  Multifactorial: Decreases in insulin, increases in glucagon, impaired NADH to NAD+ ratios from alcohol metabolism and volume depletion with vomiting.

• Associations:  Glucose levels > 250 mg/dL +/- abdominal pain +/- nausea & vomiting + ketones in the urine + serum bicarbonate < 18

• Pathophysiology:  Insufficient presence of insulin that results in the abnormal breakdown of fatty acids that generate ketoacids.

• Associations:  Ingestion of antifreeze + inebriation +/- metabolic acidosis +/- acute renal impairment

• Pathophysiology:  Ethylene glycol gets metabolized to eventually for glycolic acid and oxalic acid.

• Associations:  Iron ingestion or hemochromatosis or repeated blood transfusions

• Pathophysiology:  Results in liver damage.

• Associations:  History of tuberculosis (latent or active)

• Pathophysiology:  Due to functional deficiencies in pyridoxine (vitamin B6) that can serve as a co-factor in metabolic reactions. This leads to a metabolic acidosis.

• Associations:  Numerous medical conditions or drugs containing propylene glycol (lorazepam; phenytoin)

• Pathophysiology: Lactic acid formation is a byproduct of another underlying problem that prevents its metabolism or prevent pyruvate from entering the Krebs cycle.

• Associations:  Type 2 diabetes +/- impaired renal function

• Pathophysiology:  Impairs lactate metabolism in the liver.

• Associations:  Reports of ingestion +/- metabolic acidosis +/- changes in vision

• Pathophysiology:  Methanol is metabolized to formic acid.

• Associations:  Reports of ingestion (though no longer used)

• Pathophysiology:  Metabolized to acetaldehyde.

• Associations:  Reports of ingestion/Suicide Attempt (or) elderly patient  on chronic aspirin +/- mixed acid/base disorder

• Pathophysiology:  Initially stimulates the medullary center in the brain and causes increased respirations leading to respiratory alkalosis. Then shifts to a metabolic acidosis and uncoupling of cellular respiration.

• Differential Diagnosis:  Osmolar Gap (Elevated)
• Calculator:  Anion Gap
• Lab Test:  Anion Gap
• Toxicology:  Ethylene Glycol Overview
• Toxicology:  Isopropanol Overview
• Toxicology:  Methanol Overview
  

Editors:

• Anthony J. Busti, MD, PharmD, FNLA, FAHA

Last Reviewed:  August 2015