Causes of High-anion Gap and Non-anion Gap Metabolic Acidosis

Causes of High-anion Gap Acidosis:

 • Lactic acidosis

 • Ketoacidosis: Diabetic, Alcoholic, Starvation

 • Toxins: Ethylene glycol, Methanol, Salicylates, Propylene glycol, Pyroglutamic acid (5-oxoproline)

 • Renal failure (acute and chronic)

Causes of Non-anion Gap Acidosis:

I. Gastrointestinal bicarbonate loss

    A. Diarrhea

    B. External pancreatic or small-bowel drainage

    C. Ureterosigmoidostomy, jejunal loop, ileal loop

    D. Drugs

II. Renal acidosis

    A. Hypokalemia

        1. Proximal RTA (type 2)

        2. Distal (classic) RTA (type I)

    B. Hyperkalemia

        1. Generalized distal nephron dysfunction (type 4 RTA)

    C. Normokalemia

        1. Chronic progressive kidney disease

Ill. Drug-induced hyperkalemia (with renal insufficiency)

    A. Potassium-sparing diuretics (amiloride, triamterene, spironolactone, eplerenone)

    B. Trimethoprim

    C. Pentamidine

    D. ACE-Is and ARBs

    E. Nonsteroidal anti-inflammatory drugs

    F. Calcineurin inhibitors

IV. Other

    A. Acid loads (ammonium chloride, hyperalimentation)

    B. Loss of potential bicarbonate: ketosis with ketone excretion

    C. Expansion acidosis (rapid saline administration)

    D. Hippurate

    E. Cation exchange resins



#aniongap #NonGap #Metabolic #Acidosis #differential #diagnosis #causes #nephrology