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Pergunta: Pode poros da pele produzem sangue?
Question: Can skin pores produce blood?
Although rare, the excretion of blood through pores has been known to occur.
Critics of Christianity generally have sometimes questioned Luke's account of Christ sweating "drops of blood."
But, the phenomenon of "hemohidrosis" or "hematidrosis" (blood in the sweat), while rare, is certainly known from both historical and modern accounts.
An epidemic disease (called the sweating sickness) in England between 1485 and 1581 caused "bloody sweat." Suggested causes have included hantavirus,  relapsing fever (a tick-borne disease), or anthrax.  Influenza has also been considered, but recent reviewers remain unconvinced. 
A Chinese study reported a case of bloody sweat which described a patient in which "episodes of skin bleeding occurred on any site of the body spontaneously and promptly." The blood was identical to blood drawn from the patient's circulatory system, and the sweat glands were normal. It was hypothesized that this case was the result of a vasculitis (inflammation of blood vessels) which allowed the leak of blood. 
Another review of the literature found that the causes of modern cases of "bloody sweat" have included:
- other systemic disease
- excessive exertion
- psychologic distress
- unknown 
Thus, it seems clear that severe mental and/or physical anguish can cause this condition, just as reported by the Book of Mormon and the gospel of Luke.
- Eric Bridson, "The English 'sweate' (Sudor Anglicus) and Hantavirus pulmonary syndrome," British Journal of Biomedical Science 58/1 (1 January 2001): 1–6; first published in Medical Sciences History 14 (1998): 20–32. off-site
- E McSweegan, "Anthrax and the etiology of the English sweating sickness," Medical Hypotheses 62/1 (1 Jan 2004): 155–7. off-site
- Burke A. Cunha, "Influenza: historical aspects of epidemics and pandemics," Infectious Disease Clinics of North America 18/1 (March 2004): 141–155. off-site
- FK Zhang, Zhonghua Xue Ye Xue Za Zhi ("Clinical and laboratory study of a case of hematidrosis") in Chung-Hua Hsueh Yeh Hsueh Tsa Chih ¦ (Chinese Journal of Hematology) 25(3) (01 March 2004): 147–50. off-site
- JE Holoubek, "Blood Sweat and Fear: A classification of hematidrosis," Journal of Medicine 27/3–4 (1 Jan 2006): 115–133. off-site