Purpura is a flat, discolored spot on the skin caused by small blood vessels that leak and cause blood to pool under the skin’s surface. On light skin, purpuras appear purple. On dark skin, the patches appear dark brown or black. You may notice them on your skin or mucous membranes (e.g., inside your mouth).
There are several possible causes of purpura, ranging from use of certain medications to serious medical conditions. Some cases may be temporary, others longer-lasting. Treatment depends on the cause.
This article looks at the types, symptoms, and causes of purpura and how the condition is treated. It will help you to know when to contact your healthcare provider.
Types of Purpura
The main types of purpura are defined by whether platelets are involved. Platelets (thrombocytes) are cells in your blood that cause clots and prevent excessive bleeding.
A condition called thrombocytopenia causes low platelets. It causes bruising, bleeding into tissues, and slow blood clotting.
- Thrombocytopenic purpura is caused by low platelet counts.Nonthrombocytopenic purpura isn’t related to platelets.
Other types of purpura don’t fit into these categories. Instead, they’re tied to more serious conditions.
The size and distribution of purpura are usually determined by what’s causing them. Spots less than 4 millimeters (mm) in diameter are called petechiae.
Spots larger than 1 centimeter (cm) are considered ecchymosis.
Thrombocytopenic Purpura
Thrombocytopenic purpura (TP) is a consequence of thrombocytopenia. When platelets are low, blood doesn’t clot properly. It can be hard to stop bleeding from cuts and scrapes.
TP has other bleeding-related symptoms, other causes, and a variety of treatment options.
Signs
Thrombocytopenic purpura causes tiny purple or dark dots, and larger patches. It’s one symptom of thrombocytopenia.
Other symptoms include:
- Bleeding gumsNosebleedsBlood in the stool, urine, or vomitRectal bleedingHeavy menstrual bleedingBleeding in the head
Low platelet counts that lead to bleeding inside the skull can be a dangerous and potentially life-threatening condition, so contact your healthcare provider for a diagnosis.
Causes
TP is caused by thrombocytopenia. Thrombocytopenia can be caused by conditions that affect the platelets. These include:
- Immune (or idiopathic) thrombocytopenia: An autoimmune disease in which your immune system produces antibodies that destroy platelets.
- Neonatal alloimmune thrombocytopenia: Immune thrombocytopenia during pregnancy that can allow antibodies to cross the placenta and attack the baby’s platelets.
- Meningococcemia: A bloodstream infection caused by Neisseria meningitidis bacteria. It spreads from person to person through respiratory droplets.
- Splenomegaly: Enlargement of the spleen causing impaired function. This makes it hold on to platelets, so they can circulate in your bloodstream.
Chemotherapy drugs can damage platelets, as well. That leads to low levels.
Treatment
Treatment for TP depends on the cause. It usually resolves once the cause is treated.
Is Purpura a Symptom of Leukemia?
It can be. Some blood cancers (lymphomas and leukemias) can cause low levels of platelets. It’s been seen with some types of acute myeloid leukemia (AML), in both adults and children. It’s also been seen with chronic lymphocytic leukemia (CLL) and T-cell large granular lymphocyte leukemia (T-LGL).
Typical first-line treatments include:
- Corticosteroid medication: This stops the destruction of platelets, which quickly raises counts.Intravenous immunoglobulin (IVIg): This raises platelets quickly.
In persistent or chronic cases, treatments may include:
- Monoclonal antibodies: These drugs, such as Rituxan (rituximab), suppress part of the immune system to slow or stop platelet destruction.
- TPO-RAs (thrombopoietin receptor agonists): These drugs, including Promacta (eltrombopag) and N-plate (romiplostim), increase platelet production.
- Platelet or blood transfusions: These add platelets or blood directly into your system. Transfusions are used when the platelet count is dangerously low.
- Splenectomy: This is surgery to remove the spleen.
In some cases, an underlying infection may be treated. In children, often following a viral infection like chickenpox, the ITP usually goes away without treatment. If it doesn’t, the above treatments may be used.
Nonthrombocytopenic Purpura
Nonthrombocytopenic purpura (NTP) involves bleeding due to altered—not low—platelet function or inflammation. Damaged blood vessels leak even though platelet counts are in the normal range.
Conditions that can lead to NTP include:
- Senile (or solar) purpura: This affects older people with thinner skin and more fragile blood vessels. It causes ecchymoses on the hands and forearms that look concerning, but is usually mild and resolves on its own. Some types of vasculitis: Vasculitis may cause purpura through inflammation of the blood vessels in the skin, gastrointestinal tract, and kidneys. In rare cases, the lungs, nervous system, or other organs may be involved.
Leukocytoclastic or IgA vasculitis (formerly called Henoch-Schönlein purpura) are among the types of vasculitis that can cause purpura. A red or purple rash, as well as joint pain, is common with IgA vasculitis.
Causes of nonthrombocytopenic purpura can include:
- Blood vessel changesInflammationVirusesMedications
Senile purpura is caused by thinning and weakening skin and blood vessels. These changes are usually related to sun damage or aging. Some medications can cause purpura, including blood-thinning drugs like Coumadin (warfarin) or aspirin.
IgA vasculitis-related purpura is due to inflammation. Inflammation damages blood vessels and allows red blood cells to leak and cause a fine rash. It usually follows a respiratory illness, such as strep throat, but the exact cause is unknown.
IgA vasculitis can happen at any age but is most common between the ages of two and six. It’s also more common in boys than girls.
Other possible causes of NTP include:
- Amyloidosis: A rare medical condition in which abnormal proteins build up in your organs and tissues. That causes inflammation, which can lead to purpura.
- Congenital cytomegalovirus: An infant is infected with cytomegalovirus in the womb and is then born with it. If it’s symptomatic, it can cause a fine purpura rash.
- Congenital rubella: An infant is infected with rubella (German measles) before birth. This causes purpura plus a host of serious health problems.
- Scurvy: A disease caused by vitamin C deficiency that’s characterized by fine red and purple dots over the skin. It’s rare in the United States.
Long-term steroid use can cause purpura by destroying collagen, which is a component of small blood vessels.
Nonthrombocytopenic purpura doesn’t have specific treatments. If it’s caused by an underlying condition, treating that condition may help.
Otherwise, senile and IgA vasculitis-related cases usually go away on their own. Some people use alpha-hydroxy acid cream or tretinoin cream to make skin thicker.
Wearing protective sleeves can help to prevent bumps and bruises that lead to purpura. Some people prefer to cover the spots with makeup.
The mild joint pain of IgA vasculitis is usually treated with over-the-counter (OTC) pain medications. These include Tylenol (acetaminophen) and Advil/Motrin (ibuprofen).
Some cases of IgA vasculitis are severe or include kidney damage. It’s thought to be caused by an overactive immune system. So immunosuppressants are used to treat them.
Other Types of Purpura
Other types of purpura don’t fit into the thrombocytopenic or nonthrombocytopenic categories. They’re usually quite serious and require immediate treatment.
- Disseminated intravascular coagulation (DIC): The purpura of DIC isn’t from poor clotting but from too much of it. It makes proteins that control blood clotting overactive.Heparin-induced thrombocytopenia: Heparin is a drug used to prevent blood clots (anticoagulant). A severe reaction to it causes widespread blood clotting throughout the body. Warfarin-induced skin necrosis: In rare cases, the anticoagulant drug warfarin can lead to the premature death of skin cells. Purpura is usually one of the first signs.
Signs and Symptoms
Purpura all over the body is one sign of disseminated intravascular coagulation. The others include:
What is Purpura Fulminans
Purpura fulminans is a rare but potentially life-threatening disorder, proving fatal in up to 50% of cases. Most often, it’s a progressive condition that follows disseminated intravascular coagulation (DIC) and septic shock in a response to inflammation. It also occurs as a rare genetic disorder.
- Bleeding and blood clotsFeverHypotension (low blood pressure)Shortness of breathConfusion
Heparin-induced thrombocytopenia causes:
- PurpuraPainRedness
You may also have redness or a rash where the heparin was administered. Later signs include numbness and weakness.
Warfarin-induced skin necrosis starts with purpura, then progresses to:
- Bluish-black skin lesions with a red rimBlood-filled blistersSkin death
This condition most often affects specific areas of the body. They include:
- BreastsThighsButtocksHipsAbdomenToes (called blue toe syndrome)
The most common causes of DIC include:
- InfectionInflammationSome cancers
Less often, it can be due to:
- A reaction to a blood transfusionPancreatitisLiver diseasePregnancy complicationsTissue injuryInfectionHemangioma
Heparin-induced thrombocytopenia is caused by an immune response to heparin. Your body recognizes heparin as a foreign invader and creates antibodies against it.
Then antibodies bind to heparin in the bloodstream. That activates platelets, which causes too much clotting. Purpura is one of the first signs.
Warfarin-induced skin necrosis is a rare complication of taking the drug warfarin. You may be more at risk of complications if you have a vitamin C deficiency.
For DIC, the cause of purpura needs to be treated. Meanwhile, plasma transfusions and blood-thinning medication can help treat the symptoms.
Heparin-induced thrombocytopenia requires immediate treatment. This includes:
- Heparin therapy first has to be stopped.Warfarin may be used to clear up blood clots.Other anticoagulants like aspirin may be used as well.
Warfarin-induced skin necrosis treatment consists of:
- Stopping warfarin therapyUsing IV vitamin K to help with blood clottingPossible treatment with prostaglandins and immunosuppressants
Summary
Purpura causes dark or purples spots or patches on your skin. Thrombocytopenic purpura is caused by low platelets in the blood. Nonthrombycytopenic purpura and other types are not.
Nonthrombocytopenic purpura often doesn’t need to be treated. The others do. The treatment depends on the cause. Heparin-induced thrombocytopenia needs immediate treatment.
Usually, the focus of treatment isn’t the purpura itself, but the underlying condition that triggered it.
A Word From Verywell
Purpura can be a sign of a serious illness. If you develop purpura, see your healthcare provider so you know what’s causing it. They can provide a diagnosis and treatment options, including cosmetic care for the spots until they clear up.
Frequently Asked Questions
- Can purpura appear as a purple dot on the lips?
- Probably not. Purpura is more likely to appear in the mouth’s inner lining. A purple spot on your lip might be from an allergic reaction to food or excessive chewing on the lip.
- Learn More:
- What Is Solar Purpura Bruising?
- Does purpura look like a rash or bruise?
- Yes, purpura can resemble a rash or bruise. Bleeding underneath the skin causes tiny red or purple dots called petechiae. A group of petechiae can look like a rash.
- Learn More:
- Petechiae vs. Purpura: What Skin Discoloration Can Tell You About Your Health
- Are dark blue spots on my skin related to purpura?
- A dark blue spot on the skin can look like purpura. But it could simply be a bruise, which is also caused by ruptured blood vessels underneath the skin. Bruises heal on their own over the course of two to four weeks.
- Learn More:
- Muscle Bruise Symptoms and Treatment
Probably not. Purpura is more likely to appear in the mouth’s inner lining. A purple spot on your lip might be from an allergic reaction to food or excessive chewing on the lip.
Yes, purpura can resemble a rash or bruise. Bleeding underneath the skin causes tiny red or purple dots called petechiae. A group of petechiae can look like a rash.
A dark blue spot on the skin can look like purpura. But it could simply be a bruise, which is also caused by ruptured blood vessels underneath the skin. Bruises heal on their own over the course of two to four weeks.