Magnesium deficiency is an electrolyte disturbance in which there is a low level of magnesium in the body. It can result in multiple symptoms. Symptoms include tremor, poor coordination, muscle spasms, loss of appetite, personality changes, and nystagmus. Complications may include seizures or cardiac arrest such as from torsade de pointes. Those with low magnesium often have low potassium.Causes include low dietary intake, alcoholism, diarrhea, increased urinary loss, poor absorption from the intestines, and diabetes mellitus. A number of medications may also cause low magnesium, including proton pump inhibitors (PPIs) and furosemide. The diagnosis is typically based on finding low blood magnesium levels (hypomagnesemia). Normal magnesium levels are between 0.6 and 1.1 mmol/L (1.46–2.68 mg/dL) with levels less than 0.6 mmol/L (1.46 mg/dL) defining hypomagnesemia. Specific electrocardiogram (ECG) changes may be seen.Treatment is with magnesium either by mouth or intravenously. For those with severe symptoms, intravenous magnesium sulfate may be used. Associated low potassium or low calcium should also be treated. The condition is relatively common among people in hospitals. Signs and symptoms
Deficiency of magnesium can cause tiredness, generalized weakness, muscle cramps, abnormal heart rhythms, increased irritability of the nervous system with tremors, paresthesias, palpitations, low potassium levels in the blood, hypoparathyroidism which might result in low calcium levels in the blood, chondrocalcinosis, spasticity and tetany, migraines, epileptic seizures, basal ganglia calcifications and in extreme and prolonged cases coma, intellectual disability or death.
The kidneys regulate the serum magnesium. About 2400 mg of magnesium passes through the kidneys daily, of which 5% (120 mg) is excreted through urine. The loop of Henle is the major site for magnesium homeostasis, and 60% is reabsorbed. Magnesium homeostasis comprises three systems: kidney, small intestine, and bone. In the acute phase of magnesium deficiency there is an increase in absorption in the distal small intestine and tubular resorption in the kidneys. When this condition persists, serum magnesium drops and is corrected with magnesium from bone tissue. The level of intracellular magnesium is controlled through the reservoir in bone tissue. Diagnosis
Magnesium deficiency is not easy to directly measure. Typically the diagnosis is based on finding low blood magnesium levels (hypomagnesemia). Specifically by finding a plasma magnesium concentration of less than 0.6 mmol/L (1.46 mg/dL). Severe disease generally has a level of less than 0.50 mmol/L (1.25 mg/dL).Magnesium deficiency (or depletion) refers to low total body levels of magnesium which is usually determined by finding low blood levels (hypomagnesemia). Hypomagnesemia refers only to blood levels of magnesium. Either of magnesium deficiency and hypomagnesemia can be present without the other. Electrocardiogram
The electrocardiogram (ECG) change may show a tachycardia with a prolonged QT interval. Other changes may include prolonged PR interval, ST segment depression, flipped T waves, and long QRS duration. Treatments
Treatment of hypomagnesemia depends on the degree of deficiency and the clinical effects.