Purpura
From Wikipedia, the free encyclopedia
| Purpura Classification and external resources |
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|---|---|
| ICD-10 | D69. |
| ICD-9 | 287 |
| DiseasesDB | 25619 |
| MeSH | D011693 |
Purpura (from the Latin, purpura, meaning "purple") is the appearance of red or purple discolorations on the skin, caused by bleeding underneath the skin. Small spots are called petechiae less than 1cm, while large spots are called ecchymoses greater than 1cm.
This is common with typhus and can be present with meningitis caused by meningococcal meningitis or septicaemia.
[edit] Classification
Purpura is a common and unspecific medical sign, however the underlying mechanism commonly involves one of the following:
- Platelet disorders
- Primary thrombocytopenic purpura
- Secondary thrombocytopenic purpura
- Vascular disorders
- Microvascular injury, as seen in senile (old age) purpura, when blood vessels are more easily damaged
- Hypertensive states
- Deficient vascular support
- Vasculitis, as in the case of Henoch-Schönlein purpura
- Coagulation disorders
- Vitamin C deficiency - defect in collagen synthesis due to lack of hydroxylation of procollagen. It results in weakened capillary walls.
There are also cases of psychogenic purpura described in the medical literature,[1] some claimed to be due to "autoerythrocyte sensitization." Other studies[2] suggest, that local (cutaneous) activity of tPA can be increased in psychogenic purpura, leading to substantial amounts of localized plasmin activity, rapid degradation of fibrin clots, and resultant bleeding. Petechial rash is also characteristic of a rickettsial infection.
[edit] References
- ^ Anderson JE, DeGoff W, McNamara M (1999). "Autoerythrocyte sensitization (psychogenic purpura): a case report and review of the literature". Pediatric emergency care 15 (1): 47-8. PMID 10069314.
- ^ Lotti T, Benci M, Sarti MG, Teofoli P, Senesi C, Bonan P, et al. (1993). "Psychogenic purpura with abnormally increased tPA dependent cutaneous fibrinolytic activity". Int J Dermatol 32 (7): 521-3. doi:. PMID 8340191.
