What is thrombotic thrombocytopenic purpura (TTP)?
Thrombotic thrombocytopenic purpura (TTP) is a rare disorder that affects your blood’s tendency to clot. In this disease, tiny clots form throughout your body. These tiny clots have major consequences.
The tiny clots can block blood vessels. This stops your blood from being able to reach your organs. This can compromise the functioning of your vital organs, such as your heart, brain, and kidneys.
The tiny clots can also use up too many of your blood’s platelets. Your blood might then be unable to form clots when it needs to form them. For example, if you’re injured, you may be unable to stop bleeding.
What are the symptoms of TTP?
If you have TTP, you might have these symptoms on your skin:
- You might notice bruises that are purplish in color and have no obvious cause. These marks, called purpura, are part of what gives this condition its name.
- You might also have tiny red or purple spots that might look like a rash.
- Your skin may turn yellowish, which is called jaundice.
- Your skin may look pale.
You might also have other symptoms, such as:
- a fever
- a headache
In very serious cases, a stroke, major internal bleeding, or a coma can occur.
What causes TTP?
There’s an inherited form of TTP that transmits as an autosomal recessive trait. This means that both parents of an affected individual must carry a copy of the defective gene. The parents don’t usually have symptoms of the disease. This genetic form results from a mutation in the ADAMTS13 gene. This gene plays a role in the production of an enzyme that causes your blood to clot normally. Abnormal clotting occurs when this enzyme isn’t present. Enzymes are special proteins that increase the rate of metabolic chemical reactions.
In other cases, your body mistakenly produces proteins that interfere with the enzyme’s job. This is known as acquired TTP.
You can get acquired TTP in a variety of ways. You can develop it if you have HIV, for example. You can also develop it after certain medical procedures, such as a blood and marrow stem cell transplant and surgery.
In some cases, TTP can develop during pregnancy or if you have cancer or an infection.
Some medications can lead you to develop TTP. These include:
- hormone therapy
- cyclosporine A
How is TTP diagnosed?
Diagnosing TTP usually requires multiple tests. Your doctor may begin by performing a physical exam. This involves looking for any of the physical symptoms of the disease.
Your doctor will also test your blood. An examination of your red blood cells under a microscope will reveal whether they have damage from TTP. Your doctor will also check your blood for low platelet levels because the increased clotting causes increased use of platelets. They’ll also check for high levels of bilirubin, which is a substance that results from the breakdown of red blood cells.
Your doctor will also check your blood for:
- antibodies, which are proteins that interfere with the enzyme ADAMTS13
- creatinine levels, which increase if there’s kidney involvement due to the breakdown of muscle
- a lack of ADAMTS13 enzyme activity, which causes TTP
- lactate dehydrogenase, which is released from tissue injured by blot clots that are caused by TTP
How is TTP treated?
Doctors typically treat TPP by attempting to return your blood clotting ability to normal.
The usual treatment for inherited TTP is to administer plasma intravenously, or through an IV. Plasma is the liquid portion of blood that contains essential clotting factors. You can receive it in the form of fresh frozen plasma.
An alternative treatment that’s common for acquired TTP is plasma exchange. This means that plasma from a healthy donor replaces your plasma. During this procedure, a healthcare provider will draw your blood, just like when you donate blood. In a lab, a technician will separate the plasma from your blood using a special machine called a cell separator. They’ll replace your plasma with donated plasma. You’ll then receive this new solution through another IV. The donated plasma contains water, proteins, and essential clotting factors. This procedure takes about two hours.
Regardless of whether you have inherited or acquired TTP, you’ll likely need to have treatment every day until your condition improves.
If the plasma treatment isn’t successful, your doctor may begin to treat you with medications to stop your body from destroying the ADAMTS13 enzyme.
In other cases, your spleen might need to be surgically removed.
What is the long-term outlook?
TTP can be fatal if it’s not found and treated right away, especially when platelet levels are dangerously low. If you think you might have this condition, don’t delay in getting to your doctor or the emergency room.
If you get prompt and proper treatment for TTP, it’s likely you’ll recover well from this condition.
Some people’s TTP goes away completely after treatment. Other people may have ongoing flare-ups. Your doctor will need to check your blood counts regularly.