Share shares Her condition baffled doctors and, over the next two years, she visited more than 30 hospitals across the country desperate for a diagnosis. Doctors thought I had Lyme disease because I kept having seizures.
She is also affected by sunlight and thunder The condition, which strikes around one in , people, means she can go into life-threatening anaphylactic shock if she has a reaction pictured having an allergic reaction One doctor refused to believe her symptoms - and sent her for counselling, while another assumed her seizures were due to Lyme disease pictured in before her diagnosis Finally, in August , doctors diagnosed her with MCAS.
Mast cells, a type of blood cell, react to foreign bodies and injury by releasing a variety of chemical mediators, such as histamine, in order to fight infections. In a person with MCAS, the same chemicals are inappropriately triggered causing allergy-like symptoms. Miss Willis, who now takes 60 pills a day to combat her condition, said: Mast cell activation disorder is the umbrella term for a spectrum of diseases caused by the inappropriate activation or build-up of mast cells in the body's tissues.
Mast cells are produced in the bone marrow and are an important part of the immune system and help fight infection. When mast cells detect an allergen, they release histamine and other chemicals into the bloodstream. Histamine makes the blood vessels expand and the surrounding skin itchy and swollen. Mast cells sometimes mistake harmless substances, such as pollen, for infectious germs, and trigger the process of swelling.
This can cause the skin to become red, swollen and itchy, and it can also create a build-up of mucus in the airways, which become narrower. People with the condition have an increased risk of having a severe and life-threatening allergic reaction called anaphylaxis.
Symptoms include itchy skin or a raised, red skin rash, feeling light-headed or faint and swelling of the throat, mouth and tongue which can lead to breathing difficulties.
NHS Choices 'I have to have cool showers as hot water can trigger my allergies. One day it will be okay for me to be in the sun, and other days I can't go outside. I'd love to eat cheese, strawberries, chocolate, pastries and pies again - I miss all my favourite foods so much. If I make it out to do something with friends one night, I have to have the next day off to recover. Gawain Paling, founding trustee at MCA, says: Mast cells, a type of blood cell, react to foreign bodies and injury by releasing a variety of chemical mediators, such as histamine, in order to fight infections pictured with her mother Susan, 54 Miss Willis added: If I make it out to do something with friends one night, I have to have the next day off to recover' Share or comment on this article: London woman with MCAS can eat only rice and vegetables.