Anion Gap
From Health Facts
Latest Edit: Iva Lloyd, ND 2021-08-24 (EDT)
See Also | Lab Tests |
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This value is a measurement of the difference between the sum of the serum cations (sodium and potassium) and the sum of the serum anions (CO2/bicarbonate and chloride).[1],[2]
Discussion
- The concentrations of other extracellular anions such as phosphates, sulfates, ketones, proteins, and lactic acid are all reflected in the difference measured. Acidosis is associated with an increase in these unmeasured anions.
Patient Preparation
- Foods or fluids are not restricted.
- Factors which can cause increased levels
- Factors which can cause decreased levels
- Anything that falsely increases chloride or CO2 or falsely decreases sodium or potassium, readings in infants, high triglycerides or low protein levels
- Drugs: carbenicillin, penicillin phosphate, diuretics, antacids, licorice, and carbenoxolone
Clinical Implications
Ranges: The following are the reference ranges for this lab. However, lab ranges can vary by laboratory and country. [2]
Standard U.S. Units | Standard International Units | |
---|---|---|
Conventional Laboratory Range | 6-16 mEq/L | 6-16 mmol/L |
Optimal Range | 7-12 mEq/L | 7-12 mmol/L |
Alarm Ranges | < 4 or > 25 mEq/L | < 4 or > 25 mmol/L |
High levels indicate
- Thiamine (vitamin B1) deficiency
- Metabolic acidosis
- Drug causes: Aspirin, Diuretics, Penicillin family of antibiotics, toxins such as methanol, ethylene glycol, gold, and other heavy metals
- Other conditions: dehydration, toxin ingestion, diabetes, lactic acidosis, metabolic acidosis
Low levels indicate
- Conditions: lithium toxicity, increased serum calcium and/or serum magnesium, multiple myeloma, Neoplasm
Associated Tests
References
- ↑ Pagana Kathleen D, Pagana Timothy J, (1998) Mosby's Manual of Diagnostic and Laboratory Tests, Mosby, Inc
- ↑ 2.0 2.1 Weatherby Dicken, Ferguson Scott (2002) Blood Chemistry and CBC Analysis: Clinical Laboratory Testing from a Functional Perspective, Bear Mountain