Coeliac Kids
Overview
Immune-mediated damage to the small intestine in response to ingested gluten
Gluten is present in wheat, rye, barley, and oats
Affects 1 in 70 Australians, many are undiagnosed
Consequences
If untreated, Coeliac leads to an increased risk of
Certain lymphomas
Infertility
Premature osteoporosis
Developing other autoimmune diseases
Associated Conditions
Dermatitis herpetiformis
High rates of other autoimmune diseases including thyroid, liver disease and diabetes
Symptoms
Bloating
Diarrhoea or constipation
Large foul-smelling stools
Pain or nausea
Poor weight gain or loss
Prolonged fatigue or irritability
Severe or persistent mouth ulcers, dental enamel defects, delayed dental eruption
Unexplained low iron, B12 and folate
Short stature
Delayed puberty
Risk factors
First-degree relatives of patients with Coeliac have a 10% risk
Personal history of other autoimmune diseases (diabetes, thyroid, liver, Addison’s, IgA deficiency)
Syndromes with higher prevalence (Down Syndrome)
Testing
Blood test
Transglutaminase-IgA (tTG-IgA) and deamidated gliadin peptide IgG (DGP-IgG).
IgA levels to check concurrent IgA deficiency
DGP-IgG enhances pick-up by 15% compared to tTG-IgA alone, is unaffected by the 3% of patients with coeliac disease and selective IgA deficiency, and is more sensitive than tTG-IgA in children under age 3 years.
Consider HLADQ2 or DQ8 testing
General investigations: FBC, iron studies, vitamin B12, folate, vitamin D, LFTs, TSH.
Stool cultures
ESR/CRP
Faecal calprotectin
Diagnosis
tTG-IgA > 10x upper limit
If IgA tTG is > 10x upper limit of normal for assay, there is an option for serological diagnosis without the need for duodenal biopsies under general anaesthetic. If the family prefers serological diagnosis, send:
a second confirmatory blood sample for IgA anti-endomysial antibodies (IgA-EMA), or (if this is not available),
a repeat IgA tTG.
If either EMA is positive or the repeat IgA tTG is still > 10x the upper limit of normal for the assay, this is sufficient for confirmation. HLA-DQ2/DQ8 typing adds little to the confirmation in these cases.
IgA tTG elevated but < 10x upper limit
Request duodenal biopsies with referral and instruct the patient to remain on a gluten-containing diet.
DGP-IgG elevated
Request duodenal biopsies with referral and instruct the patient to remain on a gluten-containing diet.
In patients aged < 5 years who screen negative for tTG-IgA and DGP-IgG, consider repeat screening prior to adolescence.
In patients aged > 5 years who screen negative for tTG-IgA and DGP-IgG, but have high-risk factors and/or significant symptoms, consider HLA DQ2/8 gene testing.
Management
Life long gluten-free diet
Gluten-free diet means the exclusion of all wheat, spelt, barley, rye, and oat products.
Symptoms resolve within weeks to months.
Suggest that the family considers joining Coeliac Australia for information and support. There is a subscription fee of $100 to $110 to join.
Consider seeing a Dietitian to guide management
Symptoms should resolve with cessation of gluten
6 monthly reviews initially with repeat blood tests to check micronutrient levels e.g. iron, vitamin B12, folate, vitamin D, and calcium.
References
Coeliac disease in children - HNEPathways [Log In]
Multilingual Fact Sheets – Coeliac Australia
Fact Sheet: Coeliac Disease – HNEKidsHealth
Summary of Paeds talk at HMRI in 2023 by Dr Li-Zsa Tan
Pathophysiology
Gluten - large protein in Wheat, Barley, Rye
Incompletely digested into Gliadin
Gliadin deaminated by tTG
Peptides presented to CD4 T cells
AB produced
tTG is intracellular in all cells, and extracellular spaces, needed for wound healing + cellular proliferation
Leads to poor wound healing
Histology is lymphocytosis intraepithelially
IL15 produced
Disrupts epithelial barrier and tight junctions
Destruction of mucosa
Diagnosis
tTG-IgA = sens 93% spec 96%
EmA = sens 68 to 100, spec 77 to 100
Dgp IgG
Serological diagnosis
tTG-IgA > 10 x UL = accuracy of 99.6-100%
Endoscopy
Proximal duodenum with scalloping
Pale mucosa
Nodularity and patchy villous atrophy
Total mucosal atrophy
Symptoms
Puberty and growth delay
GI symptoms
Bone
Carditis
Depression
T cell lymphoma
Miscarriage
Cancer risk
False Positives
IBD
EoE
Autoimmune thyroiditis
Rh Arthritis
Ankylosing spondylitis
Malnutrition
Questions
Gluten-free oats contain Avenin not Gliadin, cross-contamination in factory, coeliac in remission show not change after trying GF oats but must be stable before attempting
Does GF diet prevent Coeliac? No change
