High anion gap metabolic acidosis

High anion gap metabolic acidosis
Other names	anion-gap metabolic acidosis, AGMA
Specialty	Emergency medicine, critical care, toxicology, nephrology

High anion gap metabolic acidosis is a form of metabolic acidosis characterized by a high anion gap (a medical value based on the concentrations of ions in a patient's serum). Metabolic acidosis occurs when the body produces too much acid, or when the kidneys are not removing enough acid from the body. Several types of metabolic acidosis occur, grouped by their influence on the anion gap.

The anion gap can be increased due to relatively low levels of cations other than sodium and potassium (e.g. calcium or magnesium). An anion gap is usually considered to be high if it is over 12 mEq/L.

High anion gap metabolic acidosis is typically caused by acid produced by the body. More rarely, it may be caused by ingesting methanol or overdosing on aspirin.^[1][2] The delta ratio is a formula that can be used to assess elevated anion gap metabolic acidosis and to evaluate whether mixed acid base disorder (metabolic acidosis) is present. The list of agents that cause high anion gap metabolic acidosis is similar to but broader than the list of agents that cause a serum osmolal gap.