Purpura
Purpura | |
---|---|
Petechiae and purpura on the lower limb due to medication-induced vasculitis | |
Specialty | Dermatology, hematology |
Purpura (ecchymoses greater than 1 cm.[4]
Purpura is common with
Gram-negative diplococcus organism, releases endotoxin when it lyses. Endotoxin activates the Hageman factor (clotting factor XII), which causes disseminated intravascular coagulation
(DIC). The DIC is what appears as a rash on the affected individual.
Classification
Purpura are a common and nonspecific medical sign; however, the underlying mechanism commonly involves one of:
- Platelet disorders (thrombocytopenic purpura)
- Primary thrombocytopenic purpura
- Secondary thrombocytopenic purpura
- Post-transfusion purpura
- Vascular disorders (nonthrombocytopenic purpura)
- Microvascular injury, as seen in senile (old age) purpura, when blood vessels are more easily damaged
- Hypertensivestates
- Deficient vascular support
- Vasculitis, as in the case of Henoch–Schönlein purpura
- Coagulation disorders
- Disseminated intravascular coagulation (DIC)
- Scurvy (vitamin C deficiency) – defect in collagen synthesis due to lack of hydroxylation of procollagen results in weakened capillary walls and cells
- Meningococcemia
- Clumping fibrillary protein deposits caused by Amyloidosis
- Cocaine use with concomitant use of the one-time chemotherapy drug and now veterinary deworming agent levamisole can cause purpura of the ears, face, trunk, or extremities, sometimes needing reconstructive surgery.[5] Levamisole is purportedly a common cutting agent.
- Decomposition of blood vessels including purpura is a symptom of acute radiation poisoning in excess of 2 Graysof radiation exposure. This is an uncommon cause in general, but is commonly seen in victims of nuclear disaster.
Cases of
rickettsial
infection.
Etymology and pronunciation
The word purpura (/ˈpɜːrpɜːrə/) 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 hemorrhagicain horses
- Pigmented purpuric dermatosis
- Schamberg disease (progressive pigmentary purpura)
References
- ^ "PURPURA English Definition and Meaning | Lexico.com". Archived from the original on October 17, 2019.
- ^ "UCSF Purpura Module" (PDF). Archived from the original (PDF) on 2013-10-02.
- )
- )
- PMID 21675882.
- PMID 10069314.
- S2CID 38433734.
External links
- Evaluating the Child with Purpura Archived 2008-10-16 at the Wayback Machine from American Academy of Family Physicians