This Calcium correction for hypoalbuminemia calculator reviews the serum calcium quantity in case of low albuminemia levels and corrects it. Discover more on the subject, some example calculations and learn which are the formulas used below the form.
How does this Calcium correction for hypoalbuminemia calculator work?
This health tool determines the corrected calcium in cases where the albuminemia is not in normal range, of relevance in hypoalbuminemia. There are two tabs you can use for your convenience, the first one using standard units: mg/dL serum calcium and g/dL albumin while the second one uses SI units, the serum calcium in mmol/L and albumin in g/L.
As a feature, this Calcium correction for hypoalbuminemia calculator uses the standard albumin at 4 g/dL respectively 40 g/L but you can also adapt the value on your own. Here are the formulas employed:
- The first tab formula:
Corrected Calcium = Serum Calcium (mg/dL) + 0.8 * (Normal albuminemia (g/dL) – Patient albuminemia (g/dL) )
Corrected Calcium = Serum Calcium (mg/dL) + 0.8 * (4 g/dL – Patient albuminemia (g/dL) )
- The second tab formula:
Corrected Calcium = Serum Calcium (mmol/L) + 0.02 * (Normal albuminemia (g/L) – Patient albuminemia (g/L) )
Corrected Calcium = Serum Calcium (mmol/L) + 0.02 * (40 g/L – Patient albuminemia (g/L) )
Calcium correction in hypoalbuminemia
Serum calcium is strongly connected to the level of serum albumin because albumin is the protein that binds calcium. Corrected Calcium values take into account any discrepancies, hyper or hypo of albumin levels for which the reference range is around 3.5 – 5.5 g/dL or 35 -55 g/L.
Therefore a Ca correction is required whenever albumin is not in the normal range, allowing us to determine the Ca levels as if the protein had normal values.
- In case of hypoalbuminemia, corrected calcium is higher than the tested Ca value.
- In case of hyperalbuminemia, corrected calcium is lower than the tested serum Ca.
Normal calcium levels vary between 8.5 – 10.5 mg/dL or 2.1 -2.6 mmol/L depending on the testing laboratory.
This defines low blood albumin levels, the protein which accounts for 50-60% of blood proteins. Albumin has the role of a transporter for various substances such as bilirubin, ions, hormones, fatty acids and even the exogenous drugs in medication.
When there isn’t enough albumin, these substances remain free in the plasma instead of being bound and drugs for instance, go faster through the hepatic metabolism because of that. Blood proteins are also important in sustaining the balance between osmotic and hydrostatic pressure and in preventing edema.
Unfortunately, hypoalbuminemia is common in many acute and chronic medical conditions and was determined that one fifth of admitted patients have it because of the acute and chronic inflammatory response. Amongst causes there are liver diseases, most common cirrhosis, nephrotic syndrome, heart failure, burns, malnutrition etc.
Example of two calculations
Serum calcium = 8 mg/dL
Albumin = 2.7 g/dL
Normal albumin = 4 g/dL
The result is:
Corrected Calcium = 9.04 mg/dL
Normal Calcium level is between 8.5 – 10.5 mg/dL (or between 2.1 – 2.6 mmol/L).
Serum calcium = 1.7 mmol/L
Albumin = 31 g/L
Normal albumin = 40 g/L
The result is:
Corrected Calcium = 1.88 mmol/L
Optimal Calcium level is between 2.1 – 2.6 mmol/L (or between 8.5 – 10.5 mg/dL).
1) Parent X, Spielmann C, Hanser AM. (2009) Corrected calcium: calcium status underestimation in non-hypoalbuminemic patients and in hypercalcemic patients Ann Biol Clin (Paris) 67(4):411-8.
2) Hall J. (2015) Guyton and Hall Textbook of Medical Physiology 13th ed. Elsevier Health Sciences11 Jun, 2015 | 0 comments