Sweating blood (hematidrosis) can occur but is rare.


To confirm the diagnosis of hematirosis the sweat should be examined for blood:

(1) for red blood cells

(2) hemoglobin


The hematidrosis may be localized or generalized.


Causes of sweating blood:

(1) systemic disease

(1a) severe malaria or other febrile illness

(1b) scurvy (results is capillary fragility)

(1c) severe coagulopathy

(1d) other severe illness

(2) excessive exertion

(3) psychogenic

(3a) single event (typically associated with terror or extreme frustration)

(3b) recurrent (may be triggered by anxiety, hysteria, excitement, etc)

(3c) stigmata (associated with religious fervour)

(4) menstrual-related (extragenital bleeding during menstruation)

(5) idiopathic


Differential diagnosis:

(1) red colored sweat (see previous section)

(2) application of external blood or coloring

(3) sanguinous discharge from a subcutaneous abscess

(4) bleeding from a wound


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