Corrected Calcium Calculator

Calcium correction explained

The total calcium in the body is dependent on the level of serum albumin, which is the binding protein of calcium.

The adjusted or corrected calcium refers to the part of calcium which is ionized, the part that has a biological effect.

Usually, corrected calcium is calculated whenever albumin levels are not in the normal range, thus allowing an estimate as if albumin value were normal.

The two parameters used for the calculation are:

■ Serum albumin, measured in g/dL or g/L;

■ Total calcium, measured in either mg/dL or mmol/L.

The equation used is:

Adjusted calcium = serum calcium [mg/dL] + 0.8 * (normal albumin - serum albumin [g/dL])

*where the normal albumin level is default at 4 g/dL, thus the formula becomes:

Corrected calcium = serum calcium + 0.8 * (4 - serum albumin)

The value obtained can be used in determinations that follow up on suspicion of a calcium metabolism disorder.

Where hypoalbuminemia is present (low albumin levels), corrected calcium tends to be higher than total calcium.

The table below provides an indication of the recommended daily calcium intake:

Infants260mgToddlers800mgChildren1200mgTeenagers1300mgAdults1000mgPregnant women1100mgAdults over 501100mgAdults over 701200mg

Hypercalcaemia guidelines

When the right levels of calcium are not maintained, hypo or hyper-calcaemia occur. In the case of the latter, there are different stages, depending on the calcium levels:

HypercalcaemiaTotal serum calcium levels in mg/dLMild10.5- 11.9Moderate12- 13.9Severe14- 16

Hypercalcaemia is caused by primary hyperparathyroidism (mostly in potmenopausal women) or by endocrine, electrolyte imbalances in malignancy.

Symptoms that affect the normal functioning of the central nervous system include confusion, fatigue, weakness or lethargy.

The cardiovascular and circulatory system may be affected by arrhythmias or syncope.

Renal symptoms consist of polyuria, dehydration or kidney stones and may lead to renal failure.

Nausea, abdominal pain, dyspepsia or gastric ulcer are hypercalcaemia effects on the digestive system.