There are several different things that make up what we call blood. Red blood cells are likely the most commonly considered item given that they provide the color we are all so familiar with when we get cut or otherwise break our skin. White blood cells come in a few varieties and are specialized to fight infection. Plasma is the fluid that carries everything along our vessels and also contains the clotting factors. But when we have a break in the skin, it is the platelets that are usually first on scene to stop the bleeding. If our platelets are really low then we can have a hard time controlling bleeding without outside intervention. Thrombocytopenia is the medical term for low platelets, typically defined as a platelet count less than 150,000/μL.

Causes of Thrombocytopenia

There are many different causes of thrombocytopenia. Nearly all of them are related to poor or reduced production of platelets or excessive consumption or los of platelets. Platelets are made in our bone marrow, but production is signaled by enzymes from the liver. Diseases of either of those two can lead to problems creating new platelets. There are also some genetic disorders that reduce platelet production.

Meanwhile, some drugs can destroy platelets specifically to reduce the clotting potential in a person for medical reasons. Other drugs may have a side effect of destroying platelets. Someone who has had recent injuries and resuscitative fluids in the hospital may have low platelets from them spilling out during the injuries with blood loss, used up during clotting and then the remaining ones diluted by the fluids. It takes time to replenish the supply. 

There is also an autoimmune condition where your own body attacks and destroys your platelet supply. 

FAA Disposition

If your most recent episode of thrombocytopenia was more than five years ago, and you no longer have any symptoms or ongoing issues, then your AME can issue your certificate at your exam. As always, we recommend bringing good documentation in the form of a current detailed clinical progress note if this is the first time you are reporting it. If it isn’t the first time, then bringing evidence that you have previously reported it and been issued should help with a new AME that is unfamiliar with you. 

If your most recent issue was less than five years ago then it starts to really matter what caused it and you will need to have good medical documentation. But if the thrombocytopenia was from a drug side effect, infection, pregnancy or other condition that isn’t of significant concern to the FAA, your AME is still able to issue your medical at your exam, provided you bring all the right evidence. 

Chronic Immune Thrombocytopenia (CITP)

If you happen to have the autoimmune condition where your platelets remain low, then you may still be eligible for your medical at the time of the exam via the CACI protocol. In this case you will need to meet the specific criteria from the FAA in order to qualify. Let’s take a look at what your current detailed clinical progress note will need to say in order to meet the criteria:

• The underlying cause is CHRONIC ITP and not some other reason
• Your platelets remain above 50,000/μL
• It has been more than 12 months since your diagnosis
• You have no history of bleeding episodes requiring medical intervention
• You have not needed a splenectomy as part of your treatment
• You do not need to use any antiplatelet medication or anticoagulants
• You do not have an increased risk of bleeding from another medical condition (like and ulcer or significant fall risk)
• You are not expected to need any new treatment
• Your physician has not restricted your activities
• Your most recent, within 90 days, blood counts show no anemia or leukopenia

When Your Case Must Be Deferred

If your thrombocytopenia was diagnosed less than 12 months prior to your AME exam,  then you don’t meet the criteria for the condition to be “chronic” and your AME will be obligated to defer your certification decision to the FAA. In situations like this, the FAA wants to know that your treating team truly does have the situation well understood and has fully investigated other possible causes. It does not mean that your certificate will be denied, but it does mean it needs further review. 

Because of that, if you have been diagnosed with thrombocytopenia within the past six to 12 months, you might actually get your medical certificate faster by delaying your AME exam. It commonly takes the FAA six months to review deferred medical exams. 

All other causes of the thrombocytopenia are required to be deferred. In cases where cancer or liver failure are the cause, the low platelets are just a symptom. The FAA wants to know how the underlying condition is doing before they make a decision. 

For most people with a history of thrombocytopenia, you can get your medical certificate in relatively short order provided you are doing well and have good documentation. If you don’t meet the above criteria for issuance at your exam, then it is likely because your low platelets are a symptom of a more serious condition. If you are concerned about getting your medical certificate in a timely fashion, don’t hesitate to reach out to us for a free consultation!