(or '''Hypercalcemia''') is an elevated
Calcium level in the
Blood . (Normal range: 9-10.5 mg/dL or 2.2-2.6 mmol/L). It can be an asymptomatic laboratory finding, but because an elevated calcium level is often a clue to other serious disease, a diagnosis should be undertaken if it persists. It can be due to excessive skeletal calcium release, increased intestinal calcium absorption, or decreased renal calcium excretion.
Hypercalcemia ''per se'' can result in
Fatigue ,
Depression ,
Confusion ,
Anorexia ,
Nausea ,
Vomiting ,
Constipation , or
Increased Urination ; if it is chronic it can result in urinary calculi (
Renal Stones or bladder stones). Abnormal
Heart Rhythms can result, and an
EKG finding of a short
QT Interval suggests hypercalcemia.
Symptoms are more common at high calcium levels (12.0 mg/dL or 3 mmol/l). Severe hypercalcemia (above 15-16 mg/dL or 3.75-4 mmol/l) is considered a and
Cardiac Arrest can result.
The goal of therapy is to treat the hypercalcemia first and subsequently effort is directed to treat the underlying cause.
- hydration, increasing salt intake, and forced diuresis
- ---hydration is needed because many patients are dehydrated due to vomiting or renal defects in concentrating urine. Increasing body fluid level can increase urine calcium excretion.
- ---increased salt intake also can increase body fluid volume as well as increasing urine sodium excretion, which further increases urinary calcium excretion
- ---after rehydration, saline or a Loop Diuretic can be given to force diuresis and depress renal calcium reabsorption
- ---can usually decrease serum calcium by 1-3 mg/dL within 24 h
- ---caution must be taken to prevent potassium or magnesium depletion
- Bisphosphonates are Pyrophosphate analogues with high affinity for bone, especially areas of high bone-turnover.
- ---they are taken up by Osteoclasts and inhibit osteoclastic bone resorption
- ---current available drugs include (in order to potency): (1st gen) Etidronate , (2nd gen) Tiludronate , IV Pamidronate , Alendronate , Risedronate , and (3rd gen) Zolendronate
- Calcitonin blocks bone resorption and also increases urinary calcium excretion by inhibiting renal calcium reabsorption
- ---usually used in life-threatening hypercalcemia along with rehydration, diuresis, and bisphosphonates
- rarely used, or used in special circumstances
- --- Plicamycin inhibits bone resorption (rarely used)
- --- Gallium Nitrate inhibits bone resprotion and changes structure of bone crystals (rarely used)
- --- Glucocorticoids increase urinary calcium excretion and decrease intestinal calcium absorption
--no effect in calcium level in normal or 1' hyperparathyroidism
--effective in hypercalcemia due to osteolytic malignancies ( Multiple Myeloma , Leukemia , Hodgkin's Lymphoma , Carcinoma Of The Breast ) due to antitumor properties
--also effective in Hypervitaminosis D and Sarcoidosis
- --- Dialysis usually used in severe hypercalcemia complicated by Renal Failure . Supplemental phosphate should be monitored and added if necessary
- --- Phosphate therapy can correct the hypophosphatemia in the face of hypercalcemia and lower serum calcium
