North American Veterinary Licensing Examination (NAVLE) Practice Test

An elevated anion gap is commonly associated with metabolic acidosis, and one of the classic conditions leading to this phenomenon is diabetic ketoacidosis. In diabetic ketoacidosis, there is an accumulation of ketoacids, which include acetoacetate and beta-hydroxybutyrate. These acids increase the concentration of unmeasured anions in the blood, thereby elevating the anion gap. The anion gap is calculated using the formula: Anion Gap = (Sodium) - (Chloride + Bicarbonate). When the bicarbonate concentration decreases significantly, as seen in diabetic ketoacidosis, the anion gap rises due to the increased presence of these ketoacids. This helps clinicians diagnose the condition and monitor the effectiveness of therapy. In contrast, while chronic renal failure can lead to metabolic acidosis, the anion gap may be normal or only mildly elevated due to the retention of urea and other waste products rather than an increase in unmeasured anions. Likewise, pneumonia typically doesn't cause a significant alteration in the anion gap. Liver disease can also contribute to acid-base imbalances, but it may not consistently elevate the anion gap to the same extent as seen in diabetic ketoacidosis.