Saskia explained to the GP that she had been living with IBS for several years, which she had been self-managing with over-the-counter medications. However, over the past 2 months her symptoms had worsened, with:
The GP ascertained that Saskia had not recently travelled internationally and had no family history of gastrointestinal or gynaecological disorders. Her weight was stable, and she was currently eating a range of foods with no restrictions on gluten or dairy intake. She had no blood in her stools and was not opening her bowels overnight.
Saskia was in a stable relationship, used the combined oral contraceptive pill, and denied any stress associated with her home life or studies.
The GP noticed that there was no mention of IBS on Saskia’s medical records. On further questioning, Saskia explained that she had ‘self-diagnosed’ after speaking to a friend who had a diagnosis of IBS and researching the syndrome on online forums.
A face-to-face consultation was arranged for a more thorough assessment the same day, given that Saskia had never received a formal diagnosis.
The symptoms of different gastrointestinal conditions are very similar,5 making it difficult and frustrating for both patients and healthcare professionals to identify the relevant condition.
After testing negative for COVID-19, Saskia attended the appointment. Her GP conducted a thorough abdominal examination, which was unremarkable with no palpable masses; there were also no signs of anaemia or jaundice.
Saskia declined the offer of a rectal examination, and as she was young and had no tenesmus or rectal bleeding, the GP felt that it was acceptable to proceed without one. Appropriate safety-netting advice was given in the event her symptoms should progress or change.
The GP sent off the following blood tests:
A faecal calprotectin test was considered, but the GP decided it was best to wait for the blood results before deciding how to proceed.
tTG IgA is the recommended first-line test for coeliac disease, together with total IgA to check for IgA deficiency.6
Saskia was phoned by her GP 2 weeks later, after the following blood test results had returned:
The GP explained to Saskia that her symptoms were likely due to coeliac disease and advised her to begin a strict gluten-free diet.
The prevalence of coeliac disease in patients who are diagnosed with IBS based on symptom criteria is up to 4.7 percent.
28 percent of patients with coeliac disease first receive treatment for IBS.8
Screening for coeliac disease in patients with IBS, as recommended by international guidelines,9 can help resolve symptoms,10 can improve quality of life, and is cost-eﬀective.11,12
Saskia was referred to a dietitian for specific advice regarding food-labeling, alternatives to gluten-containing foods, and how best to maintain appropriate calcium and iron intake.
A 3-monthly review was arranged to monitor her tTG IgA until levels returned to normal. In addition, an annual review was set up to check:
Saskia was signposted to coeliac disease charities for further information and support, should she require it.
It is common practice for tTG IgA to be tested every 3 months, until normalised, and once a year as an indicator of diet adherence.6
Other autoimmune conditions are more common in patients with coeliac disease than in the general population.3
Do you test tTG IgA every 3 months until normalised, for your patients with coeliac disease?
This is a fictional case study, and the image used is of a model.
FBC: full blood count; IgA: immunoglobulin A; tTG: tissue transglutaminase; ULN: upper limit of normal
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