Causes of Metabolic Acidosis

Classified by anion gap

A. High Anion-Gap Acidosis

1. Ketoacidosis

• Diabetic ketoacidosis
• Alcoholic ketoacidosis
• Starvation ketoacidosis

2. Lactic Acidosis

• Type A Lactic acidosis (Impaired perfusion)
• Type B Lactic acidosis (Impaired carbohydrate metabolism)

3. Renal Failure

• Uraemic acidosis
• Acidosis with acute renal failure

4. Toxins

• Ethylene glycol
• Methanol
• Salicylates

B. Normal Anion-Gap Acidosis (or Hyperchloraemic acidosis)

1. Renal Causes

• Renal tubular acidosis
• Carbonic anhydrase inhibitors

2. GIT Causes

• Severe diarrhoea
• Uretero-enterostomy or Obstructed ileal conduit
• Drainage of pancreatic or biliary secretions
• Small bowel fistula

3. Other Causes

• Recovery from ketoacidosis
• Addition of HCl, NH4Cl