A normal-anion-gap metabolic acidosis occurs in patients with -

Causes of Non-Anion Gap Acidosis I Gastrointestinal bicarbonate loss Diarrhea External pancreatic or small-bowel drainage Ureterosigmoidostomy, jejunal loop, ileal loop Drugs 1. Calcium chloride (acidifying agent) Magnesium sulfate (diarrhea) Cholestyramine (bile acid diarrhea) II. Renal acidosis A. Hypokalemia Proximal RTA (type 2) Distal (classic) RTA type 1) B. Hyperkalemia 1. Generalized distal nephron dysfunction (type 4 RTA) Mineralocorticoid deficiency Mineralocorticoid resistance Na+ delivery to distal nephron Tubulointerstitial disease Ammonium excretion defect III. Drug-induced hyperkalemia (with renal insufficiency) Potassium-sparing diuretics (amiloride, triamterene, spironolactone) Trimethoprim Pentamidine Angiotensin-converting enzyme inhibitors and AT-II receptor blocker. Nonsteroidal anti-inflammatory drugs Cyclosporine 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.