What is hypocalcemia?
Hypocalcemia is an electrolyte inequity and is indicated by a low level of calcium in the blood. The normal adult worth for calcium is 4.5-5.5 mEq/L.
Calcium is significant for healthy bones and teeth, as well as for normal muscle and nerve function. Usual blood calcium levels are maintained through the actions of parathyroid hormone (PTH), your kidneys, and intestines. If your blood test fallouts show hypocalcemia, your doctor may check your albumin level as well. If your albumin is low, your calcium level must be corrected for this. A modified calcium level will be higher if the albumin is low.
Signs and symptoms of hypocalcemia
Hypocalcemia is usually asymptomatic
The attendance of hypoparathyroidism may be suggested by the clinical manifestations of the original disorder (e.g., short stature, rounded facies, intellectual disability, calcification of the basal ganglia in type Ia pseudohypoparathyroidism; vitiligo with autoimmune hypoparathyroidism).
The main clinical manifestations of hypocalcemia are due to alterations in the cell membrane potential, which causes neuromuscular irritability.
Muscle cramps that affect the back and legs are common. Sinister hypocalcemia can cause mild diffuse encephalopathy and should be suspected in patients with mysterious dementia, depression, or psychosis.
Papilledema occurs occasionally
Severe hypocalcemia with serum calcium <7 mg/dl (<1.75 mmol / l) can cause hyperreflexia, tetany, laryngospasm, or generalized seizures. Tetany is usually the result of severe hypocalcemia but may be due to a reduction in the ionized fraction of serum calcium without marked hypocalcemia, as occurs in severe alkalosis. Tetany is characterized by the following:
- Sensory symptoms consisting of paresthesias of the lips, tongue, fingers, and feet.
- Carpopedal spasm, which can be prolonged and painful.
- Generalized muscle pain
- Spasm of facial muscles
Tetany can be manifest with spontaneous or latent symptoms and require provocation tests for its appearance. Latent tetany generally occurs with less severely decreased serum calcium concentrations: 7 to 8 mg / dL (1.75 to 2.20 mmol / L). Chvostek and Trousseau signs are easily obtained at the bedside to identify latent tetany. Chvostek’s sign is an involuntary contraction of the facial muscles caused by a light tapping of the facial nerve just before the outer auditory meatus. It is present in ≤ 10% of healthy people and most people with acute hypocalcemia but is often absent in chronic hypocalcemia.
Trousseau’s sign is the precipitation of carpal spasm by the reduced blood supply to the hand with a tourniquet or blood pressure cuff inflated to 20 mm Hg above systolic blood pressure applied to the forearm for 3 minutes. Trousseau’s sign also occurs in alkalosis, hypomagnesemia, hypokalemia, and hyperkalemia, and approximately 6% of people without identifiable electrolyte disturbances.
Many other abnormalities can occur in patients with chronic hypocalcemia, such as dry and flaky skin, brittle nails, and coarse hair. Candida infections occasionally occur in hypocalcemia, but occur more frequently in patients with idiopathic hypoparathyroidism. Cataracts occasionally occur with long-lasting hypocalcemia and are not reversible by correction of serum calcium.
Hypocalcemia most often occurs when too much calcium is lost in the urine or when not enough calcium is transferred from the bones to the blood. Causes of hypocalcemia include the following:
- A low level of parathyroid hormone (hypoparathyroidism), such as can occur when the parathyroid glands are damaged during thyroid gland surgery.
- Lack of response to a normal level of parathyroid hormone (pseudohypoparathyroidism)
- Absence of parathyroid glands at birth (for example, in DiGeorge syndrome)
- A low level of magnesium (hypomagnesemia), which reduces the activity of the parathyroid hormone.
- Vitamin D deficiency (due to inadequate intake or inadequate exposure to sunlight)
- Kidney dysfunction, which results in increased excretion of calcium in the urine and makes the kidneys less able to activate vitamin D
- Inadequate calcium intake
- Disorders that decrease calcium absorption
Certain medications, including rifampicin (an antibiotic), anticonvulsants (such as phenytoin and phenobarbital), bisphosphonates (such as alendronate, ibandronate, risedronate, and zoledronic acid), calcitonin, chloroquine, corticosteroids, and plicamycin.
Diagnosis of hypocalcemia
The first step in diagnosis is a blood test to determine your calcium levels. Your doctor may also use mental and physical exams to look for signs of hypocalcemia. A physical exam may include a study of your:
A mental exam may include tests to:
Your doctor may also test for the signs of Chvostek and Trousseau, both of which are related to hypocalcemia. Chvostek’s sign is a spasm response when a set of facial nerves is touched. Trousseau’s sign is a spasm in the hands or feet that comes from ischemia or a restriction in the blood supply to the tissues. Contractions or spasms are considered positive responses to these tests and suggest neuromuscular excitability due to hypocalcemia.
Treatment of hypocalcemia
- Calcium supplements
- Sometimes vitamin D
Calcium supplements, taken by mouth, are often all that is needed to treat hypocalcemia. If a cause is identified, treating the disorder causing hypocalcemia or changing medications can restore the calcium level. Once symptoms appear, calcium is usually given intravenously. Taking vitamin D supplements helps increase calcium absorption from the digestive tract. Sometimes people with hypoparathyroidism are given a synthetic form of parathyroid hormone.
Risk factors for hypocalcemia
Some risk factors can increase your potential for developing hypoglycemia.
Children with type 1 diabetes, the elderly, and people who are unfamiliar with hypoglycemia are at increased risk of developing hypoglycemia. Lack of awareness of hypoglycemia can occur if you experience low blood sugar frequently, which can make your body insensitive to symptoms. The inability to feel symptoms such as sweating, shaking, increased heart rate, anxiety, or hunger is dangerous because it can lead to loss of consciousness or even death.
Complications of hypocalcemia
Untreated hypoglycemia can lead to:
- Loss of consciousness
- Hypoglycemia can also contribute to the following:
- Dizziness and weakness
- Motor vehicle accidents
- Increased risk of dementia in older adults
- Ignorance of hypoglycemia
Over time, repeated episodes of hypoglycemia can make hypoglycemia unaware. The body and brain no longer produce signs and symptoms that warn of low blood sugar, such as tremors or irregular heartbeats. When this happens, the risk of severe and life-threatening hypoglycemia increases.
If you have diabetes, recurring episodes of hypoglycemia, and lack of knowledge of hypoglycemia, your doctor may modify your treatment, raise your blood sugar goals, and recommend blood glucose awareness training.
If you have diabetes, hypoglycemic episodes are uncomfortable and can be scary. Fear of hypoglycemia can cause you to take less insulin to make sure your blood sugar doesn’t drop too low. This can lead to uncontrolled diabetes. Talk to your doctor about your fear and do not change the dose of your diabetes medicine without your doctor’s permission.
- If you have diabetes
- Continuous glucose monitor
Follow the diabetes management plan that you and your doctor have developed. If you are taking new medications, changing your eating or medication schedules, or adding new exercises, talk with your doctor about how these changes could affect your diabetes control and your risk for hypoglycemia.
A continuous glucose monitor (CGM) is an option for some people, particularly those unfamiliar with hypoglycemia. A CGM has a tiny wire that is inserted under the skin that can send blood glucose readings to a receiver.
If your blood sugar levels are getting too low, some CGM models will alert you with an alarm. Some insulin pumps are now integrated with CGM and can stop insulin delivery when blood sugar levels are dropping too fast to help prevent hypoglycemia.
Make sure you always carry a fast-acting carbohydrate, such as glucose tablets or juice, so you can treat the drop in blood sugar before it drops dangerously low.
If you don’t have diabetes
For periodic episodes of hypoglycemia, eating frequent small meals throughout the day is a stopgap amount to help prevent blood sugar levels from dropping too low. However, this approach is not recommended as a long-term strategy. Work with your doctor to identify and treat the cause of hypoglycemia.