Complications of coeliac disease include low bone density, increased infections and mental health challenges, but there’s a lot that can be done to reduce the risk, experts say.

Symptoms aren’t always a good indicator of disease state

Intestinal injury is the hallmark of coeliac disease, but its consequences can affect multiple organ systems—and symptoms alone are a poor indicator of disease activity, says gastroenterologist Vincent Ho, Associate Professor in the School of Medicine at Western Sydney University.

“Even if someone has no obvious symptoms at diagnosis, they can still have significant intestinal damage and long-term risks from prior gluten exposure,” he says.

“The gluten triggers off that injury to the small bowel resulting in villous atrophy. So some patients may feel perfectly fine, but they may actually have nutrient malabsorption, inflammation and damage to the mucosa.”

Asymptomatic people can also have complications like iron deficiency anaemia, low bone mineral density, fertility issues, and an increased risk of intestinal cancers, he says.

“And this risk relates more to ongoing exposure and the duration of disease, not whether symptoms were present or not.”

These risks reduce substantially once a patient adopts a strict gluten free diet and achieves mucosal healing, he adds. “That’s why early diagnosis and adherence to a strict gluten free diet are so important.”

Reducing the risk of complications

Once the diagnosis has been confirmed, regular, long-term follow-up is critical, says GP Dr Katherine Kelly, founder of The Coeliac Clinic in Queensland.

Monitoring should include:

• Review of coeliac antibodies – tissue transglutaminase, gliadin and IgA testing is recommended every three to six months until the patient is well, then every one to two years once antibodies have normalised.
• Assessment of deficiencies associated with malabsorption – test iron, B12, folate, vitamin D and zinc initially, and every one to two years once they have normalised.
• Screening for associated conditions – including thyroid disease, liver disease, and type 1 diabetes.
• Bone density testing – upon diagnosis then at least every five years (or more frequently if low bone density is detected).

“Up to 75% of coeliac patients will have a low bone density at the time that they’re diagnosed,” Dr Kelly says. Patients with coeliac disease are entitled to a Medicare rebate for bone density testing, so it’s important to note their condition on the request form.

Associate Professor Ho recommends monitoring symptoms, noting that improvements in diarrhoea, bloating, and fatigue can indicate a positive response to a gluten-free diet.

Routine endoscopies and intestinal biopsies are not necessary, he stresses, although repeat testing is warranted if symptoms persist despite adherence to a strict gluten-free diet, or if blood tests remain abnormal for longer than expected.

How long does it take to see improvements on a gluten-free diet?

On average in adults, gastrointestinal symptoms begin to improve within 2-6 weeks. Symptoms like fatigue can take 3-6 months to settle, and coeliac serology typically normalises within 6-12 months, but can take up to 2 years. Partial recovery of the intestinal villi often occurs within 6-12 months, but complete mucosal healing sometimes takes over 2 years. Children generally recover faster, with GI symptoms often improving within 1-4 weeks. Serology commonly normalises within 3-6 months, and most children achieve normal blood tests and near-complete villous recovery within 12 months.

Cutting out gluten – and dispelling some myths

“One of the most important things that we should do when we have a newly diagnosed coeliac patient is refer them to a dietitian who has a special interest in coeliac disease,” Dr Kelly says.

Patients must learn how to identify gluten-containing foods, understand food labelling, and reduce the risk of cross-contamination at home. Dining out, workplace catering, social gatherings and travel can all be challenging, she notes.

“There is a lot more to the gluten-free diet than simply avoiding pasta and bread.”

Advanced Accredited Practicing Dietitian Dr Kim Faulkner-Hogg, lead dietitian with Coeliac Australia, says newly diagnosed patients are often anxious about accidental contamination, sometimes believing it will cause immediate and severe intestinal damage.

“I use the analogy of the gluten lawnmower,” she says. “They believe that if this crumb of gluten that they couldn’t even see comes into their body, this gluten lawnmower is just going to go through their gut, and they’ll have no villi left. And that gives them a lot of mental anguish.”

Importantly, ongoing intestinal injury is more likely to result from repeated small and large exposures over time than from isolated trace incidents, Dr Faulkner-Hogg notes.

Dietitians help patients understand the risks of trace exposure and ways to reduce it, like avoiding gluten-contaminated utensils and unwashed cooking equipment.

Staple gluten free items often don’t have the same nutritional content as the wheat foods they are replacing, so dietetic input can also help patients achieve a nutritionally balanced diet, minimising the risk of deficiencies and improving microbiome and bone health, she adds.

Vaccinations

“Some individuals with coeliac disease also have functional hyposplenism. So they have a lifelong increased risk of bacterial infections—particularly with the encapsulated bacteria,” Dr Kelly explains.

In addition to standard vaccines and annual influenza vaccination, patients with functional hyposplenism should receive pneumococcal, meningococcal (ACWY and B) and haemophilus influenzae type b vaccinations, she advises.

The Australian Immunisation Handbook has a table listing recommendations for people with asplenia and hyposplenia of various ages.

Practice tip: Add details of vaccines and boosters into your practice software so patients get an automatic reminder when they are due.

Managing mental health

“There’s a significant link between coeliac disease and mental health complaints, both before and after treatment,” Dr Kelly notes.

A population-based Swedish study found that childhood coeliac disease was associated with a 19% overall increase in psychiatric disorders, including an increased risk of anxiety disorders, mood disorders, eating disorders, ADHD and autism, with heightened risk persisting into adulthood.

“The increased risk of psychiatric disorders before diagnosis is thought to be related to the systemic inflammatory response we get with untreated celiac disease,” Dr Kelly says. “But we also see mental health conditions with treated coeliac disease.”

This is thought to be related to the treatment itself, she explains.

“Unlike other chronic medical conditions, coeliac disease cannot be managed with pharmaceutical approaches. The only treatment for coeliac disease mandates a major lifestyle change—a strict lifelong adherence to a gluten-free diet. This treatment has been rated by patients to be highly burdensome.”

She encourages GPs to check in with patients regularly and ask how they’re coping.

“And if there are any issues, consider a referral through a mental health care plan, if appropriate, to a psychologist who has an interest in chronic disease.”

What to do if symptoms persist

Persistent diarrhoea, weight loss, abdominal pain, bloating, steatorrhea, or nutritional deficiencies with biopsy evidence of villous atrophy after following a strict gluten-free diet for at least 12 months can signify refractory coeliac disease, Associate Professor Ho says.

“And they may be more at risk of complications such as ulcerative jejunitis, and of developing very serious complications such as T-cell lymphoma.”

However, the most common reason for ongoing villous atrophy is continued gluten exposure, he says.

“And they may be unaware of that. It may be that when they go out to eat, they can be exposed to gluten, and so we really need to make sure that somebody is strictly on a gluten-free diet for that 12-month period before diagnosing refractory celiac disease.”

It’s also important to rule out other possibilities like pancreatic insufficiency and small intestinal bacterial overgrowth, and specialist input is helpful here, he says.

“If there’s any concerns about weight loss, malabsorption, persistent diarrhoea, if all that is happening despite a gluten-free diet, then referring early would be important so we can start some key investigations and get this condition under control.”

Refractory coeliac disease involves ongoing immune activation in the absence of gluten exposure. It is usually managed with immune modulating agents, although oral steroids, and occasionally biologics, are sometimes necessary, he says.

Key takeaways

• Lifelong monitoring should include coeliac serology, nutritional markers, bone density testing and screening for associated conditions
• All newly diagnosed patients should be referred to a dietitian with expertise in coeliac disease
• People with coeliac disease are at increased risk of infection due to functional hyposplenia and require additional vaccinations
• Mental health impacts are common and should be routinely assessed as part of ongoing care
• Persistent symptoms despite a strict gluten-free diet warrant investigation for ongoing gluten exposure, alternative diagnoses or refractory coeliac disease