Bleeding disorders can be caused by Platelet Function Disorders-M

Platelet Function Disorders are rare blood conditions that affect only 2000 – 5000 in the UK.
The term ‘Platelet Function Disorder’ (PFD) could be applied to any condition where platelets do not work properly.

Platelets are small particles in the blood that stick together at sites on injury (for example after a cut) to form a “plug” and stop the bleeding. If your platelets don’t work properly you bleed more than normal and this can vary from minor bruising to life threatening bleeding after surgery or an accident.

PFD stands for platelet function disorder(s), meaning that platelets do not work properly. Some patients with PFD have a normal platelet count, and some have a reduced platelet count (the medical term for this is “thrombocytopenia”). Most platelet disorders are acquired, meaning they appear spontaneously or as a result of an external factor; such as a change in the immune system, in kidney function, or as a result of medications. These conditions may disappear or “remit”. However, a small number of patients are born with inherited PFD, meaning that they will always have the condition.

How do Platelets affect day to day life?

This varies a lot according to the type of PFD. Some patients only get very minor bruising which can be painful and not look very nice, but is not life threatening. Some patients can have really severe bleeding such as nosebleeds that won’t stop and lead to anaemia (a low red blood cell count), bleeding from the bowel, or very heavy periods in young girls and women. The most serious type of bleeding is bleeding inside the head or brain, sometimes referred to as intracranial haemorrhage. Having surgery (or having children in women) is a time of particular worry and many patients need treatment prior to these events.

Patients with PFDs will be registered with the doctors and nurses at a haemophilia centre and will see them intermittently or if they need treatment. The haemophilia centre can often be a long way from their home, and attending can make patients miss time from work or school. Some patients carry a treatment pack with them at all times so they can give treatment quickly if they do develop a bleed.

Most patients with PFD in the UK carry a \’green card\’ to alert medical staff to the fact that they have a bleeding disorder. Simple things like going on holiday can be problematic, as patients with PFDs will need to find out where they should go if they develop a problem whilst they are away, and they may need to carry treatment with them. Some patients with PFDs are advised not to participate in sports with a lot of physical contact or risk of head injury, such as rugby or boxing. The label of having a PFD and the symptoms associated with it can cause embarrassment and stigma to some patients who just want to be \’normal\’.
Why is it important to know more about Platelets?

Diagnosing an inherited PFD is complicated, so at present some patients who bleed more than normal don’t know if they have a PFD or not. Research into improving the diagnosis will hopefully help these patients and also their families by giving them a more specific diagnosis. Testing is normally only done by specialist centres given the rarity of inherited PFDs. Acquired PFDs can often be diagnosed on the basis of a patient’s clinical features and current and previous blood results.

At the moment, PFDs are all treated in a similar way, but knowing more about the different types of PFD may improve treatment options and mean treatment can be tailored to the specific PFD that a patient has. Lastly, finding out more about their inheritance will help future generations and will give young patients with PFD very important information with regard to planning their families.
Anyone can have an inherited PFD, and getting them is not caused by any factors in the diet or in the environment such as smoking or drinking alcohol. Many patients with inherited PFD are diagnosed when they are children as they bruise a lot when they are toddling or playing, but some patients are not diagnosed until much later in life, even into their seventies. In families where other members of the family are known to have inherited PFD parents will often be alert to the possibility and have children tested at a very young age.

As mentioned above, inherited PFD only make up a small portion of all platelet disorders, and the remainder are acquired, meaning they appear spontaneously or as a result of an external factor. Examples include changes in the immune system leading to immune thrombocytopenia purpura or ITP, and changes in kidney function changing the way platelets work. Many medications also disrupt platelet function, such as painkillers / anti-inflammatories and antidepressants.
What treatments are available?

Current treatments for patients with inherited PFD include tranexamic acid liquid, tablets or injections, which strengthen blood clots and make them resistant to being broken down. Desmopressin or \’DDAVP\’ is also given either as a nasal spray or an injection under the skin to increase the platelets’ stickiness. In serious bleeding platelet transfusion may be given, although only if absolutely necessary.
Injections of other clotting factors such as factor VII (seven) are sometimes used, and new agents which are based on the platelet stimulating hormone thrombopoietin may become more widely used over the next few years (this makes the bone marrow produce more platelets).

For patients with acquired PFD, treatment is normally related to the cause – for example in ITP treatments target the immune system.