High anion gap metabolic acidosis

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.

The most common causes of high anion gap metabolic acidosis are: ketoacidosis, lactic acidosis, renal failure, and toxic ingestions.[3]

Ketoacidosis can occur as a complication of type I diabetes mellitus (diabetic ketoacidosis), but can occur due to other disorders, such as chronic alcoholism and undernutrition. In these conditions, excessive free fatty acid metabolism results in the production of ketoacids, acetoacetic acid, and beta-hydroxybuterate.

Lactic acidosis results from excess formation and decreased metabolism of lactate, which occurs during states of anaerobic metabolism. It is the most common cause of metabolic acidosis in hospitalized patients. The most serious form occurs during various states of shock, due to episodes of decreased liver perfusion.

E — Ethylene glycol (Note: Ethanol is sometimes included in this mnemonic as well, although the acidosis caused by ethanol is actually primarily due to the increased production of lactic acid found in such intoxication.)

T — Toxins (Ethylene glycol, methanol, as well as drugs, such as aspirin, Metformin)

The preferred mnemonic of D. Robert Dufour, the chief of the Pathology and Laboratory Medicine Service, Veterans Affairs Medical Center, is DUMPSALE, which omits the I of MUDPILES as the proposed values of *I* are exceedingly rare in clinical practice.[citation needed]

D — Diabetic ketoacidosis

U — Uremia

M — Methanol

P — Paraldehyde

S — Salicylates

A — Alcoholic ketoacidosis

L — Lactic acidosis

E — Ethylene Glycol

The mnemonic for the [rare, in comparison] toxins is ACE GIFTs: Aspirin, Cyanide, Ethanolic ketosis, Glycols [ ethylene and propylene ], Isoniazid, Ferrous iron, Toluene. Most of these cause a lactic acidosis.[citation needed]