Disease Spotlight: Autoimmune Thrombocytopenic Purpura

Today’s Disease Spotlight is on autoimmune thrombocytopenic purpura, a bleeding disorder caused when your immune system destroys your platelets – the cells in your blood that allow it to clot. Like many diseases on our list — you guessed it!! — this one goes by several different names. 

Autoimmune thrombocytopenic purpura is also known as immune thrombocytopenic purpura, idiopathic thrombocytopenic purpura, or by initials ATP and ITP (where the “I” stands for idiopathic or immune), or even just thrombocytopenia.  Some will refer to it simply as purpura. Some medical professionals don’t use the terms idiopathic or autoimmune at all when referring to thrombocytopenic purpura. 

As we’ve discussed in previous blog posts, when a disease goes by many names, patients may not realize that others are suffering alongside them simply because of the name their doctor used for their disease andeach name may be seen as rare by the medical community. Just imagine a disease that sickens 1 million people (like Parkinson’s), but there are 4 different names being used. That could mean only 250,000 patients use one of those names – and that is small enough to be categorized as a rare disease by the National Institutes of Health. Being a rare disease may be an advantage for some funding, but it gives everyone the impression that it’s not as big a problem as it really is.

To confuse things further, ITP can refer to the condition whether it is caused by autoimmunity or not. This is true of many conditions caused by autoimmunity. The problem is that the immune system causes damage. That damage is what leads to the illness, but that damage could be caused by other things – a virus, age, or even injury.   Because we are focused on autoimmune diseases, we are interested in the autoimmune form of the condition. 

ITP can mean idiopathic or immune, so we will use ATP since it clearly refers to autoimmune-caused thrombocytopenic purpura.

ATP can be chronic or acute. Most autoimmune diseases are chronic, but not all of them are.  Other examples of acute, relapsing, or sporadic autoimmune illnesses include certain forms of multiple sclerosis and some types of hepatitis, among others. 

So what is ATP?  

In patients with ATP, antibodies mistakenly identify healthy platelets as invading microbes and the immune system destroys them. An excellent description of how this happens can be found on the Platelet Disorder Support Association website. 


Since platelets are the cells in the blood that allow it to clot, the blood in patients with ATP does not coagulate (clot) properly. That leads to one of the most common symptoms:  bruising, with red or purple (“purpura” is Latin for “purple”) spots on the skin, which gives the condition its name. Other symptoms include frequent nosebleeds, bleeding gums, heavy menstrual periods in women, blood in urine or stool, and, in rare cases, even brain bleeds. As with many autoimmune diseases, fatigue is also a hallmark of this condition.

The prevalence of ATP is currently estimated at 30,000 people in the United States. The Autoimmune Registry continues to gather data about this and other autoimmune diseases so that we can confirm existing prevalence data and begin to understand the patterns and underlying causes of these diseases.

It starts with you — so please, get involved! We need donations to our organization, patients to fill out our survey, and patient advocacy groups (PAGs) to begin sharing information with us and about us. We’re looking for bloggers, too, to share the ATP patient experience so that you have a place to go for information and camaraderie. 

So, if you live with thromobcytopenic purpura or are an ATP/ITP blogger, patient advocate or advocacy group, we’d love to hear your story. Please email ashley@autoimmuneregistry.org if you wish to contribute a guest blog about life with ATP. In the meantime, please visit the Platelet Disorder Support Association or the ITP Foundation for more information and check out our ATP fact sheet, here. And don’t forget to join our free registry, so we can learn more about what life is like for you as an autoimmune patient.