Young patients suddenly "paralyzed", alert to hyperthyroidism and hypokalemia

Chen Ruihua

What causes the young guy to have repeated chest tightness and palpitations? What causes quadriplegia in fitness youth? And what, let the guys enter the rescue room as soon as they come out of the barbecue stall?

A few days ago, a young patient suddenly came to the emergency department of the hospital, suddenly weak limbs, and blood potassium was only 1.6 mmol/L. After medical history questioning, the guy said that he has been thin since childhood, loves fitness, loves food, loves travel, loves staying up late, that is, poor gastrointestinal function, and always likes to run to the toilet.

However, in the past six months, as soon as I exercise, I have chest tightness, panic is obvious, sometimes the limbs are paralyzed, and a few minutes of rest can relieve itself. He just thought that he was overexercising and did not pay attention to it. Before coming to the emergency department this time, he first "stroked the iron" for 2 hours, and then gathered with his friends at the barbecue stall to eat, but he didn't expect that he suddenly couldn't move his hands and feet, and after a few minutes, he was like paralysis, almost thinking that he had a cerebral infarction.

What kind of disease does the guy have? Physical examination showed that the patient was relatively thin, bright eyes, bright eyes, bright eyes, slightly shortness of breath, warm and moist skin on the limbs, and the most significant feature was a 2nd degree enlargement of the thyroid gland and a heart rate of 120 beats per minute. This is typical hyperthyroidism.

Hyperthyroidism can be mild or severe, and this patient happens to have a complication of hyperthyroidism, hyperthyroid hypokalemic paralysis. Potassium that is too low can be life-threatening, but as long as the potassium is replenished and hyperthyroidism is treated, the alarm can be lifted.

Hypokalemia is quiet, but the consequences can be fatal

Hyperthyroidism refers to an endocrine disorder caused by the inappropriate synthesis and secretion of too much thyroid hormone by the thyroid gland located in the neck. The main clinical manifestations are hypermetabolism and increased excitability of nervous, circulatory and digestive systems.

Typical symptoms of hyperthyroidism include irritability, irritability, insomnia, palpitations, fatigue, heat intolerance, sweating, weight loss, hyperphagia, increased stool frequency, or diarrhea. May be associated with hypokalemic periodic paralysis (more common in Asian men) and progressive weakness and atrophy of the proximal muscles.

Many people only know hyperthyroidism but not low potassium, and hypokalemia occurs quietly, but the consequences can be fatal.

Potassium is the 19th element in the periodic table and an essential trace element found in all fruits and vegetables. 98% of the elemental potassium in the human body is found in cells, and the rest is found in extracellular fluid, such as blood, urine, digestive juices, etc.

The normal concentration of potassium in the blood is 3.5-5.5 mmol/L, and the body is sensitive to sharp fluctuations in blood potassium, especially the heart. Excessive potassium can lead to hyperkalemia, causing bradycardia, and severe can lead to malignant arrhythmias such as ventricular fibrillation.

Low potassium is divided into three grades: light, medium and severe, and the blood potassium concentration of 3.0-3.5 mmol/L is mildly hypokalized, 2.5-3.0 mmol/L is moderately hypokalized, and less than 2.5 mmol/L is severe hypokalemia. Severe hypokalemia can lead to tachycardia, arrhythmias, atrial fibrillation, and even cardiac arrest.

At the same time, the muscle tissue of the limbs is prone to myolysis and muscle paralysis, and the gastrointestinal tract, kidney, liver and other tissues are also prone to damage in the state of low potassium. Therefore, young hyperthyroid men with low potassium will have quadriplegia, numbness in the hands and feet, difficulty breathing, and abdominal bloating.

Young men should pay attention to the fact that potassium supplementation as soon as possible is key

There are three main reasons for low potassium: eating less; Row more; Abnormal intracellular and extracellular distribution, uneven rich and poor. Hyperthyroidism is prone to low potassium, mainly related to excessive excretion and abnormal intracellular distribution.

■ Increased excretion

Diarrhea: patients with hyperthyroidism have accelerated intestinal peristalsis, increased frequency of stool, more likely to have diarrhea, the digestive juice in the intestine is rich in potassium, and the digestive juice taken away by diarrhea will cause a large amount of potassium loss, causing low potassium;

Hyperhidrosis: patients with hyperthyroidism due to high basal metabolism, are afraid of heat and sweating, if heavy physical activity is carried out in a high temperature environment, can be due to a lot of sweating, take away more potassium, if there is no timely potassium supplementation, can cause low potassium, so low potassium is more likely to occur in the high temperature season;

■Transfer of potassium ions into cells

Elevated insulin after eating: young patients with hyperthyroidism usually have a strong appetite due to rapid metabolism, eat more food, and glucose entering the blood will stimulate increased insulin secretion, which can enhance the activity of the cell sodium and potassium pump, so that the extracellular potassium is transferred into the cell. The potassium in the blood is originally much lower than the intracellular level, and the potassium in the blood runs into the cell, resulting in a decrease in blood potassium;

Directly promote potassium transfer to intracellular: Patients with hyperthyroidism produce too much thyroid hormone, which will directly act on the potassium channels on the cell surface, causing potassium to transfer to the cell, resulting in low potassium. In severe cold, in order to protect the cold, catecholamine secretion increases, promotes metabolic thermogenesis, and also promotes the flow of potassium ions into cells, resulting in potassium deficiency in the blood.

This explains why people with hyperthyroidism are prone to low potassium – full meal fatigue, nervousness, cold, high-sugar diet, glucose injections and insulin injections.

However, the root cause of low potassium in hyperthyroid patients is hyperthyroidism itself, so potassium supplementation is the treatment of the symptoms, and the treatment of hyperthyroidism is the root cause. Patients with hyperthyroid periodic paralysis need potassium supplementation as soon as possible, intravenous and oral parallel, to restore blood potassium to normal levels as soon as possible, and then iodine 131 treatment as soon as possible, after the treatment of hyperthyroidism, hypokalemia will not occur again.

If it is a young man, he is relatively thin, afraid of heat, sweating, in strenuous exercise, a large number of diets after sudden limb weakness, it is necessary to consider this disease, as soon as possible to send to the hospital, immediate treatment is the key. At this time, time is life, and potassium supplementation is life.

(The author is a doctor of endocrinology and metabolism at Shanghai First People's Hospital)