HARDASS Mnemonic for Normal Anion Gap Metabolic Acidosis

What does HARDASS stand for?

H – Hyperalimentation

Normal gap metabolic acidosis is caused on by hyperalimentation in the form of overeating and Total Parenteral Nutrition (TPN).

A – Addison’s Disease

Addison’s disease, where there is a loss of aldosterone, leads to metabolic acidosis because of decreased activity of the the H+/ATPase pump in the intercalated cells of the collecting duct. As hydrogen is not secreted, due to a lack of aldosterone, H+ is retained inside the cells and consequently causes blood acidemia.

R – Renal Tubular Acidosis

Another reason for Normal Anion Gap Metabolic Acidosis is renal tubular acidosis. Acid builds up in the body as a result of the kidneys’ inability to properly acidify the urine.

D – Diarrhea

Due to an excessive loss of bicarbonate through the GI tract, diarrhea is a major cause of normal gap metabolic acidosis.

A  – Acetazolamide

A Normal Anion Gap Metabolic Acidosis can result from the loss of bicarbonate in the urine caused by carbonic anhydrase inhibitors like Acetazolamide.

S – Spironolactone

A Normal Anion Gap Metabolic Acidosis can be brought on by Spironolactone, which prevents aldosterone’s effects on the distal tubule. This is because a lack of aldosterone causes the sodium-hydrogen exchanger to waste sodium in the urine, leaving H+ in the serum.

S – Saline Infusion

Rapid infusion or sufficiently large doses of plasma expanders, such as normal saline, can sometimes lead to Normal Anion Gap Metabolic Acidosis.