Detection and treatment of hypocalcaemia

Hypocalcaemia is a condition in which blood calcium levels are deficient due to lack of calcium or vitamin D deficiency or both. If hypocalcaemia is high, it can cause many dangerous diseases such as arrhythmia, cardiac conduction disorder .

The role of calcium in the body

Stable maintenance of calcium in the body depends on three main factors: food, drinking water, calcium absorption from the intestine and excretion by the kidneys.

The daily requirement of a diet sufficient to provide about 1,000 mg of calcium through the diet is about 200mg of calcium excreted via the bile and other digestive juices. Each day about 200 - 400mg of calcium is absorbed from the intestine into the blood and this process depends on the concentration of vitamin D in the blood, the remaining calcium is excreted in the feces.

Calcium balance is maintained through the route of renal excretion, averaging 200 mg / day. Nearly 99% of the body's calcium is concentrated in the bones, mainly in the form of hydroxyapatite crystals. Only 1% of calcium in bones is free to exchange with extracellular fluid, so it is always ready to regulate stable blood calcium levels . The normal total calcium concentration in the blood is maintained ranging from 8.8 to 10.4 mg / dl (2.20 to 2.60 mmol / l).

Causes of hypocalcaemia

Hypocalcaemia is when the total serum calcium concentration is below 8.8 mg / dl (2.20 mmol / l) under normal serum protein conditions, or ionized calcium below 4.7 mg / dl (1, 17 mmol / l). There are many causes, mainly:

Increased bone production while providing insufficient calcium (rapidly developing children, women who are pregnant and nursing mothers), malabsorption syndrome due to prolonged gastrointestinal disorders; Hypothyroidism, reduces the secretion of parathyroid hormones causing hypocalcemia, hypercholesterolemia and often causes chronic tetani episodes. The cause is often due to injury or removal when thyroid surgery; Suppose the parathyroid gland; Vitamin D deficiency; Kidney disease: renal tubular pathology, renal failure.

Other causes : Magnesium deficiency, acute pancreatitis, reduced blood albumin, increased blood phosphorus. Drugs that cause hypoglycemia such as antiepileptic drugs (phenobarbital, phenytoin), rifampicin, high blood transfusions, contrast drugs, high doses of calcitonin.

Expression of hypocalcaemia

The clinical manifestations of hypocalcaemia are due to membrane membrane potential disturbances, which stimulate the neuromuscular system. Common signs are muscle cramps (cramps) in the back and legs. Cases of hypocalcaemia slowly, latent can cause mild neurological signs such as depression, confusion or mental stimulation. Edema and cataract may occur when prolonged hypocalcaemia.

Tetani is caused by severe hypocalcaemia but it can also be encountered in the case of only lowering ionized calcium while normal calcium is normal, for example in the condition of blood alkalization. The manifestation of tetani episodes are sensory symptoms such as paresthesia in the head, lips, tongue, table of the feet, diffuse myalgia, muscle spasm in the face, hands and feet. In addition to spontaneous tetani attacks, a number of treatments are also used to find specific signs of hypocalcemia.

Hand shrinkage (Trousseau sign / hand support) in lowering blood calcium.

Chvostek signs are manifested by spontaneous facial muscle contraction after tapping lightly on the facial nerve in the position right in front of the ear canal. This sign is seen in most cases of acute hypocalcemia.

Trouseau signs are expressed by shrinking the muscles of the wrist and hands that appear when reducing the amount of blood supply to the hands, this sign also occurs in lowering magnesium, blood alkalosis, hypokalemia. Arrhythmias or cardiac conduction disturbances may occur in some cases of severe hypocalcemia.

Symptoms of hypocalcaemia are common in adults

Increased tendon reflexes (discreet manifestations can be detected by Chvostek signs are caused by tapping on the face of the facial nerve, in front of the outer ear 2 cm and observing the co-contracting condition of the side However, this sign is both non-sensitive (27%) and is not specific and can be seen in 25% of normal subjects)

1. Abdominal pain.
2. Arrhythmia (irregular heartbeat).
3. Depression.
4. Irritable / uncomfortable.
5. Sleeping chick or slow / lazy being.
6. Muscle spasms.
7. Convulsions.

Common symptoms of hypocalcaemia in newborns

1. Difficulty in feeding and eating.
2. Irritability / irritation.
3. Sleepy or slow / lazy.
4. Anorexic.
5. Increased tendon reflexes (signs Chvosteck).
6. Muscle shrinkage (Trousseau sign).
7. Seizures and tremors.

Chvosteck sign.

What are the complications of hypocalcaemia?

Complications of untreated hypocalcemia may seriously affect the development and health of young children. For adults, complications can also be serious. You can reduce the risk of serious complications by following the treatment plan you and your doctor have planned for you. Complications of hypocalcaemia include:

1. Can't be big
2. Motor function and brain damage
3. Malnutrition
4. Osteomalacia (soft bone, weak due to lack of vitamin D during bone formation)
5. Osteoporosis (thin and weak bones)
6. Poor development - Tetany (excessive mental activity, extremely painful)

Treatment of hypocalcaemia

In the case of acute hypoglycemia such as tetani bouts , it should be treated with slow intravenous injection for about 10 minutes 10ml of calcium gluconate or calcium chloride 10%, the symptoms usually go away quickly after injection but the effect is usually short, only pull a few hours long. Therefore, it may be repeated or slow intravenous infusion (20-30 ml of 10% calcium gluconate mixed in 5% glucose 1 infusion for 12-24 hours).

Special attention is given to patients taking digoxin cardiac drugs (very slow infusion and continuous electrocardiographic monitoring). When tetani attacks combine with low blood magnesium levels, magnesium and calcium must be added simultaneously. In the case of hypocalcaemia after parathyroidectomy, only calcium supplementation by mouth (1g / day) is sufficient.

With chronic hypocalcaemia, oral calcium supplementation and sometimes combination with vitamin D are sufficient. Calcium gluconate or calcium carbonate may be used, ensuring 1-2g of calcium per day. In the case of hypocalcaemia due to kidney failure, calcitriol should be used because the drug does not need further metabolism in the kidneys. In case of hypoparathyroidism, calcitriol should be used at a dose of 0.5-1 mcg / day. In the case of pseudo hypoparathyroidism, only simple calcium treatment (1 mg / day) is usually required.

To prevent disease, all cases must enhance calcium rich foods such as shrimp, crab, fish, milk, cheese . and enhance outdoor exercise (increasing vitamin D synthesis increases calcium absorption in the intestine).