Millie's story

Millie’s consultant believes she has Mast Cell Activation Syndrome (MCAS), and her Paediatric Allergist has described her as his most complex case. 


For her whole life, Millie has suffered multi-systemic symptoms that have impacted every aspect of her life. Despite this, Millie is a determined and hardworking, innately kind young girl. As a very young child, Millie would suffer from mouth ulcers, tummy aches and diarrhoea, and nausea whilst eating. When Millie was 2 years old, we removed dairy from her diet under the care of a dietician; although her condition improved a little, she was still not well. The dietician checked for coeliac disease, and we removed gluten from her diet, but things did not improve and blood tests for IgE allergies came back negative.  

We kept a food diary which revealed that Millie was reacting to egg - if exposed to eggs she would get hives and flushing.  Over the next few years, whilst Millie improved on her egg and dairy-free diet, we knew something was still not right because she would be going to the toilet up to 7 or 8 time a day. We were also concerned because Millie was always tired and had very dark circles under her eyes. A well as suffering from constant tummy aches and regular nausea, she had a reduced appetite and had episodes of blood in her stools. 


When she was nearly 6 years old, we were referred to the Paediatric Gastroenterologist who agreed that something was not right; he undertook a colonoscopy and endoscopy in January 2016, and the results ruled out IBD, Crohn’s disease and colitis. The Gastroenterologist suggested that Millie have the hydrogen breath test for fructose malabsorption and lactose intolerance, both were positive. As Millie continued to be ill with vulvodynia, headaches and throat swelling, we trialled a fructose-free and low FODMAP diet. Although some of her symptoms lessened, she was still not totally well. During the summer, Millie had a bad reaction, but we had not knowingly given her anything with fructose in; an Australian dietician, via a Facebook support group, realised that the foods she was reacting to were all high in salicylates and amines, so we decided to trial a low-salicylate diet. Many of Millie’s symptoms went away or lessened – for example, her back pain, leg pain, blocked ears, nasal congestion, diarrhoea and hives all reduced, and she felt much better in herself. She looked healthier than she had in years. 

Despite the improvement, Millie was still not 100% and her episodic reactions were still increasing in severity. She was already dairy, egg-, fructose, and sucrose-free; on a low-FODMAP diet; and avoiding salicylates but was still reacting. We investigated possible other reasons for this and learned that Millie was reacting to various environmental triggers such as sudden temperature changes, as well as emotions like getting angry or anxious. A consultant told us that he did not believe Millie could truly have so many sensitivities, and instead he believed we are seeing mast cells at play. In March 2017, we also saw a paediatric allergist, who suspected Millie either had chronic idiopathic urticaria with angioedema or mast cell activation syndrome.  

Millie had a positive test result for elevated histamine and prostaglandin levels, which was six times the upper limit! 


In November 2016, Millie’s consultant  prescribed Nalcrom, which made a massive difference – in fact, Millie was totally well for the first time ever. He also prescribed fexofenadine but Millie had a severe reaction to it, and this reaction alongside a food trial caused her to become unstable again. In 2017, Millie’s paediatric allergist prescribed more antihistamines, but Millie also reacted to these. However, a sodium cromoglicate inhaler vastly improved her symptoms and enabled us to add more foods into her diet. 

Now, Millie is reasonably stable but has a very limited list of medications that she can tolerate. Our whole family life revolves around her condition and every decision we make has to weigh up the risk to Millie. She can no longer go into shops with very smelly products; we can't book a holiday or stay with family or go to busy places where there will be lots of strong perfumes or cleaning products – there is even something at the hospital that makes Millie unwell. Millie currently sees four consultants; a gastroenterologist, allergist, haematologist, and dermatologist.  

We need joined-up care for this condition and pathways to diagnose and treat the disease before more patients continue to suffer throughout their lives, like Millie. 


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