High anion gap metabolic acidosis is a medical condition that occurs when the body produces too much acid, resulting in an anion gap greater than normal. Synonyms for this condition include hyperchloremic acidosis, lactate acidosis, ketoacidosis, and renal tubular acidosis. Hyperchloremic acidosis refers to an elevated level of chloride ions in the blood, which are responsible for the acidity of the blood. Lactate acidosis occurs when there is an increase in lactic acid production, which can be caused by a lack of oxygen or impaired glucose metabolism. Ketoacidosis is a type of acidosis that results from the breakdown of fats in the body, and renal tubular acidosis is a condition that affects the kidneys.