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Updated: Jul 17, 2026
06:47
Measurement and Analysis of Extracellular Acid Production to Determine Glycolytic Rate
Published on: December 12, 2015
Approach to Patients With High Anion Gap Metabolic Acidosis: Core Curriculum 2021
Andrew Z Fenves1, Michael Emmett2
1Division of Nephrology, Department of Internal Medicine, Massachusetts General Hospital, and Medical School, Harvard University, Boston, Massachusetts.
Summary
The anion gap (AG) calculation helps differentiate metabolic acidosis types, guiding diagnosis and identifying occult disorders. Correcting AG for albumin and glucose levels improves diagnostic accuracy in complex cases.
Area of Science:
- Nephrology
- Clinical Chemistry
- Internal Medicine
Background:
- The anion gap (AG) is a crucial calculation in acid-base disorder assessment.
- It categorizes metabolic acidosis into high AG metabolic acidosis (HAGMA) and hyperchloremic types, aiding etiological delimitation.
Observation:
- Comparing AG with bicarbonate changes can reveal occult acid-base disorders.
- A very small or negative AG may indicate underlying clinical disorders or electrolyte measurement artifacts.
Findings:
- This curriculum discusses common and rare causes of HAGMA using case scenarios.
- The AG serves as a vital diagnostic clue for clinicians.
- Methods for calculating and correcting AG for hypoalbuminemia and hyperglycemia are presented.
Implications:
- Understanding AG variations aids in diagnosing complex acid-base disturbances.
- Incorporating plasma osmolality and osmolal gap calculations enhances clinical decision-making.
- Accurate AG assessment is essential for appropriate patient management in nephrology and internal medicine.
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