<s>[INST] context: The anion gap is equal to the difference between the plasma concentration of sodium, the major cation in the plasma, and the sum of the concentrations of plasma chloride and bicarbonate, the major measured anions in the plasma.Anion gap = - ( + )The normal plasma concentrations of Na+, Cl-, and HCO3- are 142, 105, and 24 mEq/L, respectively.The normal anion gap is about 12 mEq/L and is comprised of minor ions, such as lactate, phosphate, and sulfate.The anion gap is useful in differentiating the causes the metabolic acidosis.High anion gap metabolic acidosis results from an increase in unmeasured organic anions, such as occurs in the lactic acidosis accompanying tissue hypoxia, the accumulation of ketoacids in diabetes and its resultant coma, or by an increase in organic anions or their metabolic byproducts produced from such ingested toxins as ethylene glycol, methanol, and salicylates.COPD and myasthenia gravis are causes of respiratory acidosis. Nasogastric suctioning causes metabolic alkalosis. [/INST] question: Which of the following is associated with an increased anion gap? | options: A: Myasthenia Gravis B: Chronic obstructive pulmonary disease C: Diabetic coma D: Nasogastric suctioning | answer: C </s>