Keshan Disease: A Potentially Fatal Endemic Cardiomyopathy in Remote Mountains of China

Abstract

Keshan disease (KD) as an endemic, highly lethal cardiomyopathy, first reported in northeast China's Keshan County in 1935. The clinical manifestations of patients with KD include primarily congestive heart failure, acute heart failure, and cardiac arrhythmia. Even though some possible etiologies, such as viral infection, fungal infection, microelement deficiency, and malnutrition, have been reported, the exact causes of KD remain poorly known. The endemic areas where KD is found are remote and rural, and many are poor and mountainous places where people are the most socioeconomically disadvantaged in terms of housing, income, education, transportation, and utilization of health services. To date, KD is a huge burden to and severely restricts the economic development of the local residents and health systems of the endemic areas. Although efforts have been made by the government to control, treat, and interrupt disease transmission, the cure for or complete eradication of KD still requires global attention. For this reason, in this review, we systematically describe the etiological hypothesis, clinical manifestations, incidence characteristics, and treatment of KD, to facilitate the better understanding of and draw more attention to this non-representative cardiovascular disease, with the aim of accelerating its elimination.

The Impact of Selenium Deficiency on Cardiovascular Function

“…Supporting this hypothesis, administration of oral Se reversed Se deficiency and improved outcomes of KD [ 25 , 26 ]. Although there is some debate about whether Se deficiency is the primary cause of KD as there are several additional underlying causes, it remains until now the most convincing possibility [ 1 , 26 ].…”

“…Selenium (Se) is an essential trace element necessary for a variety of biological functions in animals, including cardiovascular function. Se deficiency has been linked to different cardiovascular diseases, including cardiomyopathies such as Keshan’s disease (KD) [ 1 , 2 ], heart failure [ 3 , 4 ], and myocardial infarction [ 5 ]. Although there has been increasing evidence of the importance of Se for optimal cardiovascular function, the role of Se in cardiovascular syndromes, particularly under dietary Se deficiency, remains only partially understood.…”

Selenium status in adults and children in Lusaka, Zambia

“…In Zambia, cardiomyopathy accounts for 75% morbidity and 30% mortality of all cases seen at the Adult Medicine Hospital in Lusaka (University Teaching Hospital Adult medicine records). Se deficiency is known to be involved in Keshan disease, a severe form of cardiomyopathy endemic to China [ 33 ], and a study in Nigeria showed that Se levels of less than 70 μg/L was a risk factor for development of peripartum cardiomyopathy [ 34 ]. Given that 99% of pregnant women in our study had plasma Se < 40 μg/L, this is a point of particular concern.…”

The Relevance of Plant-Derived Se Compounds to Human Health in the SARS-CoV-2 (COVID-19) Pandemic Era

“…SeMet is, however, the main organic form of Se in plants, while SeCys is dominant in animal based-food [106]. Se supplemented in the form of SeMet to the human diet was reported to promote the synthesis of defensive proteins and antioxidant enzymes present on the mucosal surface, which is a physical barrier that prevents the entry of pathogens into the body [107]. After intake, SeMet is absorbed in the intestine through transporters for methionine and can then be metabolized in two different ways; it either directly participates in the protein synthesis, or is converted to SeCys, which is further metabolized with the production of selenide.…”

“…This process was at least reported for coxsackievirus B3 (CVB3), influenza virus type A /Bangkok/1/79 (H3N2), influenza H1N1, human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS), polio, hepatitis B and C, and hantavirus [28]. Keshan disease, for instance, arises when CVB3 mutates to a more virulent strain in a host deficient in Se [87,107,138,139]. Unfortunately, RNA viral mutations are reported to be faster, more frequent, and long-lasting in Se-flawed hosts [140].…”