Spotlight on… dermatitis herpetiformis
Hannah Blake interviews Norma McGough
This month on pharmaphorum, we have a disease focus on dermatology. To coincide with this focus, we explore the symptoms and treatments of dermatitis herpetiformis, a skin condition caused by coeliac disease.
Our latest ‘spotlight on’ takes a look at a skin condition that is caused by coeliac disease, called dermatitis herpetiformis.
Coeliac disease is not a food allergy or intolerance to wheat and / or gluten, like most people believe. It is in fact an autoimmune disease, whereby the lining of the small intestine becomes damaged through the consumption of gluten. Coeliac disease affects 1 in 100 people in the UK, however under-diagnosis is a big problem. It’s said that only 10 – 15% of people with coeliac disease have been diagnosed.
A skin problem associated with coeliac disease is dermatitis herpetiformis. We speak with Norma McGough from Coeliac UK about this skin condition, which affects approximately 1 in 10,000 people – less common that coeliac disease, but awareness is still needed to overcome the issue of under-diagnosis.
“Coeliac disease affects 1 in 100 people in the UK, however under-diagnosis is a big problem.”
Norma shares with us the symptoms and treatments of dermatitis herpetiformis, including her thoughts on how pharma can better support patients.
HB: Hi Norma, thanks for speaking to me. What is dermatitis herpetiformis?
NM: Dermatitis herpetiformis or DH is a skin condition. It’s a skin manifestation of coeliac disease. It appears as blisters mainly on the elbows, knees and buttocks, but it can actually occur anywhere, and it’s diagnosed by a skin biopsy. With this procedure a small piece of normal skin is removed that is very near to the area of blistering but is not blistered itself. It’s very important that the biopsy is taken from the appropriate area in terms of getting an accurate biopsy result.
HB: What causes it in the first place?
NM: It’s caused by an intolerance to gluten. Gluten is a protein found in wheat, barley, and rye, and it is also therefore the same gluten intolerance that affects people with coeliac disease. Some people may also be sensitive to oats. It’s occurring in about one in 10,000 people, and it’s more common in men than women, usually appearing in adulthood.
HB: What are the symptoms to look out for?
NM: DH looks a bit like a blister that is itchy and also that stings. It usually presents as a cluster of blisters. It occurs on the elbows and knees very frequently, but it can occur anywhere on the body. People may also have the usual gut symptoms associated with coeliac disease, because the two conditions can occur together. Therefore having confirmed the diagnosis of DH by skin biopsy, people should be referred to a gastroenterologist to have endoscopy with biopsy to see if they also have the typical damage to the lining of the gut as seen in coeliac disease.
“A skin problem associated with coeliac disease is dermatitis herpetiformis.”
HB: What treatments are available?
NM: The main, long-term, treatment is a gluten free diet, because the skin disease is caused by an intolerance to gluten, which is found in wheat, barley, rye and some people are also sensitive to oats. Once gluten is removed from the diet, the symptoms and the condition will relapse. With DH, the blisters may take some time to completely disappear having established a gluten free diet, and so it is a very individual response to the treatment. It may be a matter of weeks before people going on a gluten free diet get relief, but it may take longer than that for the diet to be totally affective as a complete treatment.
Sometimes, medication is necessary at diagnosis, which can provide relief from the skin problems and discomfort during those first stages. Any medication requirements would need to be assessed by the doctor. The most common medication is called dapsone (diamino-diphenyl sulfone), which is a sulphur based oral antibiotic that needs to be monitored very carefully. The dose is usually tailored to the individual and reduced as time goes on, as the gluten free diet gets established and becomes more effective. If people can’t tolerate dapsone then there are additional treatments that are sometimes used, and again response may be individual. But drugs like sulphur pyridine and tetracycline can be beneficial in some cases, but the main objective is to get people compliant with a gluten free diet as the medication is a short term aid.
HB: How can pharma better support patients with DH?
NM: By having awareness of the symptoms and the treatments, and to also realise that DH is very much an associated condition of coeliac disease. Then, pharmacists can help advise their customers to see their GPs with ongoing problems that are characteristic for further investigations, such as the blister appearance on the elbows and buttocks, and also if they have the symptoms of coeliac disease which may include gut problems, ongoing diarrhoea and malabsorption symptoms, or anaemia. If pharmacists recognised these symptoms as coeliac disease or dermatitis herpetiformis then they can help support the patients by making sure that they go to their doctor to discuss these symptoms further and to have further investigations whether it is endoscopy with biopsy or actual skin biopsy.
Pharmacists can also have a role, once people have a firm diagnosis, of helping people on a gluten free diet, to eliminate gluten from their diet. This requires the elimination of the staples like bread and pasta and flour-based products, and to replace those normal foods with gluten free foods which are available for people medically diagnosed with both coeliac disease and also DH on prescription. And so the pharmacist has a clear role in helping to advise people on food products on prescription.
“…pharmacists can help to support their individual customers in receiving a clear diagnosis…”
HB: Finally, what does the future look like for DH patients?
NM: With earlier diagnosis due to the increased awareness of coeliac disease and dermatitis herpetiformis, DH will hopefully be much less of a problem. Skin problems may be missed or hidden or concealed, and it’s important that we raise awareness so that healthcare professionals like pharmacists can help to support their individual customers in receiving a clear diagnosis with the benefits of a complete treatment as well. Once coeliac disease and dermatitis herpetiformis are identified, the gluten free diet does provide a complete treatment, and can be controlled relatively easily in the long term.
Coeliac UK is a charity that supports people with both coeliac disease and dermatitis herpetiformis – we aim to improve the lives of people with coeliac disease and dermatitis herpetiformis and we campaign to raise public awareness. We have an awareness week between the 13th and 17th May where we’re trying to improve awareness of diagnosis.
HB: Thank you for speaking with me today, Norma.
For more information about Coeliac UK’s awareness week, please visit their website here.
About the interviewee:
Norma McGough is a registered dietitian who started her career working in the health service. She has worked in the voluntary sector for twenty years, heading teams at both Diabetes UK and currently at Coeliac UK. Norma has worked at Coeliac UK since 2003 and is head of the policy team, whose remit also covers the areas of research and campaigning.
Working as a member of the senior management team that leads the Charity in the strategic development of its knowledge base, Norma also plays a key representational role among stakeholders in the health and food sectors.
How can we raise further awareness of underlying conditions?