This is an uncommon cause in general, but is commonly seen in victims of nuclear disaster.Cases of psychogenic purpura are also described in the medical literature, some claimed to be due to "autoerythrocyte sensitization". Other studies suggest the local (cutaneous) activity of tissue plasminogen activator 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. Etymology and pronunciation
The word purpura () comes from Latin purpura, "purple", which came from ancient Greek πορφύρα. Purpura is a mass noun naming the condition or state, not the name of an individual spot (thus there is no *pupurum, *purpura or *purpura, *purpurae count declension). See also
Bruise, which is a hematoma caused by trauma
Petechia, which is a small type of hematoma (<3 mm)
Ecchymosis, which is a large type of hematoma (>1 cm)
Purpura secondary to clotting disorders
Purpura hemorrhagica in horses
Pigmented purpuric dermatosis
Schamberg disease (progressive pigmentary purpura)

References
External links

Evaluating the Child with Purpura from American Academy of Family Physicians
Therefore, cancer cells which divide much more rapidly than most other cells in the body will be more severely affected by decitabine just because they replicate more. In cancer cells, and more specifically in haematological malignancies, it seems that DNA hypermethylation is really critical for their development. Methylation of CpG islands upstream of tumor suppressor genes in order to silence them seems to be critical for these type of cancers. Thus at optimal doses, decitabine blocks this type of methylation and has an anti-neoplastic effect. Research
Atherosclerosis
A number of investigators have shown a relationship between atherosclerosis and disturbed blood flow. This upregulates DNA methyltransferase expression, which leads to genome-wide DNA methylation alterations and global gene expression changes. These studies have revealed several mechanosensitive genes, such as HoxA5, Klf3, and Klf4, whose promoters were hypermethylated by disturbed blood flow, but rescued by DNA methyltransferases inhibitors such as 5-aza-2-deoxycytidine. It has been found that use of this DNA methyltranferase inhibitor prevents atherosclerosis lesion formation and reduces the production of inflammatory cytokines by macrophages. References
Further reading
Moon C, Kim SH (June 2009). "Use of epigenetic modification to induce FOXP3 expression in naïve T cells". Transplant. Proc. 41 (5): 1848–1854. doi:10.1016/j.transproceed.2009.02.101. PMID 19545742. External links
"Decitabine". Drug Information Portal. U.S. National Library of Medicine.