Hematidrosis (also called hematohidrosis) He-ma-ti-drosis is a very rare condition in which a human being sweats blood. It may occur when a person is suffering extreme levels of stress, for example, facing his or her own death. Several historical references have been described; notably by Leonardo da Vinci: describing a soldier who sweated blood before battle, men unexpectedly given a death sentence, as well as descriptions in the Bible, that Jesus experienced hematidrosis when he was praying in the garden of Gethsemane (Luke 22,44).

There are a few names and conditions which may pertain to this, such as hematochromatosis, or staining of tissues with blood pigment. Hemochromatosis a disorder due to deposition of hemosiderin in the parenchymal cells, causing tissue damage and dysfunction of the liver, pancreas, heart, and pituitary. Other clinical signs include bronze pigmentation of skin, arthropathy, diabetes, cirrhosis, hepatosplenomegaly, hypogonadism, and loss of body hair. Full development of the disease among women is restricted by menstruation and pregnancy.

There are varying degrees of hemochromatosis, including:

Acquired hemochromatosis

Results from blood transfusions or excessive dietary iron, or secondary to other disease, e.g., thalassemia or sideroblastic anemia; called also secondary hemochromatosis.

Genetic, hereditary, and idiopathic hemochromatosis

An autosomal recessive disorder of iron metabolism associated with a gene tightly linked to the A locus of the human leukocyte antigens (HLA). complex on chromosome 6; iron accumulation is lifelong, with symptoms appearing usually in the fifth or sixth decades of life.

Neonatal and perinatal hemochromatosis

A rare fulminant disease of the liver, of unknown cause, characterized by massive deposition of iron in the liver, pancreas, heart, and endocrine glands; symptoms are those of neonatal hepatitis and appear in utero or within the first week of life, with death usually occurring by 4 months of age.

Cutaneous hemorrhage

According to Dr. Frederick Zugibe (Chief Medical Examiner of Rockland County, New York) it is well-known, and there have been many cases of it. The clinical term is hematohidrosis. "Around the sweat glands, there are multiple blood vessels in a net-like form. Under the pressure of great stress the vessels constrict. Then as the anxiety passes the blood vessels dilate to the point of rupture. The blood goes into the sweat glands. As the sweat glands are producing a lot of sweat, it pushes the blood to the surface - coming out as droplets of blood mixed with sweat."

In a lecture, Dr. Zugibe stated: "The severe mental anxiety...activated the sympathetic nervous system to invoke the stress-fight or flight reaction to such a degree causing hemorrhage of the vessels supplying the sweat glands into the ducts of the sweat glands and extruding out onto the skin. While hematidrosis has been reported to occur from other rare medical entities, the presence of profound fear accounted for a significant number of reported cases including six cases in men condemned to execution, a case occurring during the London blitz, a case involving a fear of being raped, a fear of a storm while sailing, etc. The effects on the body is that of weakness and mild to moderate dehydration from the severe anxiety and both the blood and sweat loss."

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