Purpura () is a condition of red or purple discolored spots on the

skin Skin is the layer of usually soft, flexible outer tissue covering the body of a vertebrate animal, with three main functions: protection, regulation, and sensation. Other animal coverings, such as the arthropod exoskeleton, have different ...

that do not blanch on applying pressure. The spots are caused by

bleeding Bleeding, hemorrhage, haemorrhage or blood loss, is blood escaping from the circulatory system from damaged blood vessels. Bleeding can occur internally, or externally either through a natural opening such as the mouth, nose, ear, urethr ...

underneath the skin secondary to platelet disorders, vascular disorders, coagulation disorders, or other causes. They measure 3–10 mm, whereas

petechia A petechia (; : petechiae) is a small red or purple spot ( 1 cm in diameter) and purpura (3 to 10 mm in diameter). The term is typically used in the plural (petechiae), since a single petechia is seldom noticed or significant. Causes Physical t ...

e measure less than 3 mm, and ecchymoses greater than 1 cm. Purpura is common with

typhus Typhus, also known as typhus fever, is a group of infectious diseases that include epidemic typhus, scrub typhus, and murine typhus. Common symptoms include fever, headache, and a rash. Typically these begin one to two weeks after exposu ...

and can be present with

meningitis Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, intense headache, vomiting and neck stiffness and occasion ...

caused by meningococci or

septicaemia Sepsis is a potentially life-threatening condition that arises when the body's response to infection causes injury to its own tissues and organs. This initial stage of sepsis is followed by suppression of the immune system. Common signs and s ...

. In particular, meningococcus (''

Neisseria meningitidis ''Neisseria meningitidis'', often referred to as the meningococcus, is a Gram-negative bacterium that can cause meningitis and other forms of meningococcal disease such as meningococcemia, a life-threatening sepsis. The bacterium is referred to a ...

''), a

Gram-negative Gram-negative bacteria are bacteria that, unlike gram-positive bacteria, do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. Their defining characteristic is that their cell envelope consists ...

diplococcus organism, releases endotoxin when it lyses. Endotoxin activates the Hageman factor (clotting factor XII), which causes

disseminated intravascular coagulation Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking Microvessel, small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems ...

(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 ** Hypertensive states **Deficient vascular support **

Vasculitis Vasculitis is a group of disorders that destroy blood vessels by inflammation. Both artery, arteries and veins are affected. Lymphangitis (inflammation of lymphatic vessels) is sometimes considered a type of vasculitis. Vasculitis is primarily c ...

, as in the case of Henoch–Schönlein purpura * Coagulation disorders **

Disseminated intravascular coagulation Disseminated intravascular coagulation (DIC) is a condition in which blood clots form throughout the body, blocking Microvessel, small blood vessels. Symptoms may include chest pain, shortness of breath, leg pain, problems speaking, or problems ...

(DIC) **

Scurvy Scurvy is a deficiency disease (state of malnutrition) resulting from a lack of vitamin C (ascorbic acid). Early symptoms of deficiency include weakness, fatigue, and sore arms and legs. Without treatment, anemia, decreased red blood cells, gum d ...

(

vitamin C Vitamin C (also known as ascorbic acid and ascorbate) is a water-soluble vitamin found in citrus and other fruits, berries and vegetables. It is also a generic prescription medication and in some countries is sold as a non-prescription di ...

deficiency) – defect in collagen synthesis due to lack of hydroxylation of procollagen results in weakened capillary walls and cells * Meningococcemia *Clumping

fibril Fibrils () are structural biological materials found in nearly all living organisms. Not to be confused with fibers or protein filament, filaments, fibrils tend to have diameters ranging from 10 to 100 nanometers (whereas fibers are micro to ...

lary protein deposits caused by

Amyloidosis Amyloidosis is a group of diseases in which abnormal proteins, known as amyloid fibrils, build up in tissue. There are several non-specific and vague signs and symptoms associated with amyloidosis. These include fatigue, peripheral edema, weigh ...

Cocaine Cocaine is a tropane alkaloid and central nervous system stimulant, derived primarily from the leaves of two South American coca plants, ''Erythroxylum coca'' and ''Erythroxylum novogranatense, E. novogranatense'', which are cultivated a ...

use with concomitant use of the one-time chemotherapy drug and now veterinary deworming agent

levamisole Levamisole, sold under the brand name Ergamisol among others, is a medication used to treat parasitic worm infections, specifically ascariasis and hookworm infections. It is taken by mouth. Side effects may include abdominal pain, vomiting, ...

can cause purpura of the ears, face, trunk, or extremities, sometimes needing

reconstructive surgery Reconstructive surgery is surgery performed to restore normal appearance and function to body parts malformed by a disease or medical condition. Description Reconstructive surgery is a term with training, clinical, and reimbursement implicat ...

. Levamisole is purportedly a common cutting agent. *Decomposition of blood vessels including purpura is a symptom of acute radiation poisoning in excess of 2 Grays of radiation exposure. This is an uncommon cause in general, but is commonly seen in victims of nuclear disaster. Cases of

psychogenic A psychogenic effect is one that originates from the brain instead of other physical organs (i.e. the cause is psychological rather than physiological) and may refer to: *Psychogenic pain *Psychogenic disease *Psychogenic amnesia *Psychogenic coug ...

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 Tissue-type plasminogen activator, short name tPA, is a protein that facilitates the breakdown of blood clots. It acts as an enzyme to convert plasminogen into its active form plasmin, the major enzyme responsible for clot breakdown. It is a s ...

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 Purple is a color similar in appearance to violet light. In the RYB color model historically used in the arts, purple is a secondary color created by combining red and blue pigments. In the CMYK color model used in modern printing, purple is ...

", which came from ancient Greek πορφύρα. ''Purpura'' is a

mass noun In linguistics, a mass noun, uncountable noun, non-count noun, uncount noun, or just uncountable, is a noun with the syntactic property that any quantity of it is treated as an undifferentiated unit, rather than as something with discrete eleme ...

naming the condition or state, not the name of an individual spot (thus there is no *''purpurum'', *''purpura'' or *''purpura'', *''purpurae'' count declension).

References

External links

Evaluating the Child with Purpura
from

American Academy of Family Physicians The American Academy of Family Physicians (AAFP) was founded in 1947 to promote and maintain high-quality standards for family medicine, an offshoot of the classical general practitioner. It is headquartered in Leawood, Kansas. AAFP is one of ...

{{Authority control Dermatologic terminology Medical signs

Classification

Etymology and pronunciation

See also

References

External links