Keshan disease is a congestive
cardiomyopathy caused by a combination of
dietary deficiency of selenium and the presence of a mutated strain of
Coxsackievirus, named after
Keshan County
Keshan () is a county in western Heilongjiang province, China, about northeast of Qiqihar, which administers it. It is named from a city-shaped extinct volcano, which has a name of Erkeshan in its territory. Its total area is , with a population ...
of
Heilongjiang
Heilongjiang is a province in northeast China. It is the northernmost and easternmost province of the country and contains China's northernmost point (in Mohe City along the Amur) and easternmost point (at the confluence of the Amur and Us ...
province, Northeast China, where symptoms were first noted. These symptoms were later found prevalent in a wide belt extending from northeast to
southwest China, all due to
selenium
Selenium is a chemical element; it has symbol (chemistry), symbol Se and atomic number 34. It has various physical appearances, including a brick-red powder, a vitreous black solid, and a grey metallic-looking form. It seldom occurs in this elem ...
-deficient soil. The disease peaked in 1960–1970, killing thousands of people.
Often fatal, the disease affects children and women of child-bearing age, characterized by
heart failure
Heart failure (HF), also known as congestive heart failure (CHF), is a syndrome caused by an impairment in the heart's ability to Cardiac cycle, fill with and pump blood.
Although symptoms vary based on which side of the heart is affected, HF ...
and
pulmonary edema
Pulmonary edema (British English: oedema), also known as pulmonary congestion, is excessive fluid accumulation in the tissue or air spaces (usually alveoli) of the lungs. This leads to impaired gas exchange, most often leading to shortness ...
. Over decades, supplementation with selenium reduced this condition.
It had been linked to the
coxsackie B virus. Current research suggests that the lack of selenium results in a more virulent strain of the coxsackievirus becoming the dominant
viral species present in the population of virus, but the mechanism of this selection event is unclear.
Keshan disease can also lead to higher rates of cancer, cardiovascular disease, hypertension, and strokes. In addition, an individual can experience eczema, psoriasis, arthritis, cataracts, alcoholism, and infections.
Signs and symptoms
There are four main types of Keshan disease: acute, subacute, chronic, and latent.
Some signs and symptoms of acute Keshan disease include dizziness,
malaise, nausea, chills, loss of appetite, projectile vomiting, pallor, low arterial blood pressure (less than 80/60 mmHg),
dyspnea, precardiac (anterior to the heart) or substernal (behind or below the sternum) discomfort,
cardiogenic shock
Cardiogenic shock is a medical emergency resulting from inadequate blood flow to the body's organs due to the dysfunction of the heart. Signs of inadequate blood flow include low urine production (<30 mL/hour), cool arms and legs, and decreased ...
, and constricted veins in one's extremities.
Some signs and symptoms of subacute Keshan disease include malaise, restlessness,
gallop rhythm, facial
edema, heart dilation, and cardiac shock.
Some signs and symptoms of chronic Keshan disease include palpitations, dyspnea, cough (with blood), pain in one's right upper quadrant, edema,
oliguria
Oliguria or hypouresis is the low output of urine specifically more than 80 ml/day but less than 400ml/day. The decreased output of urine may be a sign of dehydration, kidney failure, hypovolemic shock, hyperosmolar Hyperglycemic Nonketotic Syndro ...
, enlargement of the heart, systolic murmur, gallop rhythm, and
hepatomegaly.
Some signs and symptoms of latent Keshan disease include dizziness, fatigue, palpitations, and mild enlargement of the heart.
Treatments
The treatment for Keshan disease is selenium supplementation. The recommended amounts are fifty-five micrograms of selenium per day for adult men and women, sixty micrograms a day for women during pregnancy and seventy micrograms per day for women after pregnancy. A doctor may insist that if a man is sexually active, he may have to take up to seventy micrograms of selenium per day. A doctor may also recommend that the individual take vitamin E; selenium and
vitamin E
Vitamin E is a group of eight compounds related in molecular structure that includes four tocopherols and four tocotrienols. The tocopherols function as fat-soluble antioxidants which may help protect cell membranes from reactive oxygen speci ...
are medically linked and seem to work together. An individual will also be advised to have a diet that includes seafood, meats such as kidney, and liver, and some grains and seeds; all of these are high in selenium.
Brewer's yeast and
wheat germ both contain high levels of selenium. Garlic, onions, mushroom, broccoli, tomatoes, radishes, and Swiss chard may be good sources of selenium if the soil in which they are grown contains it. An individual will have to be monitored once they begin to take the selenium supplements, due to the fact that too much of it can cause balding, intestinal distress, weakness, and slow mental functioning. Individuals in China with the disease treat it with a herb called ''
Astragalus'', which accumulates selenium from the soil.
Living with Keshan disease
An individual will most likely be prescribed selenium supplements (in the form of
selenomethionine) or have injections of this mineral. Other recommendations for managing Keshan disease are to increase consumption of foods rich in selenium in addition to supplements, avoid alcohol, monitor side effects to medications, and increase sleep. Cardiac surgery (implants, stents or full heart transplant) may be advised.
See also
*
Selenium deficiency
*
Kashin–Beck disease
References
External links
{{Heart diseases
Heart diseases
Mineral deficiencies
Enterovirus-associated diseases