Paediatrics chapters
Coeliac disease
An immune enteropathy triggered by gluten in genetically prone children: who gets it, how it presents, the anti-tTG and biopsy route to diagnosis, lifelong gluten exclusion and long-term follow-up.
- Coeliac disease is a lifelong immune enteropathy caused by gliadin in wheat, barley and rye, in children carrying susceptible HLA types (DQ2, DR3); it is commoner with type 1 diabetes, Down syndrome, Turner syndrome, IgA deficiency and thyroid disease.
- Classic picture: chronic diarrhoea, abdominal distension, wasted buttocks, irritability and failure to thrive starting 6 to 24 months after wheat is introduced; atypical cases have short stature, anaemia or no symptoms.
- Diagnose with IgA anti-tTG (or anti-endomysial) plus total IgA, then duodenal biopsy on a gluten diet (villous atrophy, crypt hyperplasia, intraepithelial lymphocytes); treat with a lifelong gluten-exclusion diet.
On this page
Overview
Coeliac disease (gluten-sensitive enteropathy) is an immune-mediated injury of the small bowel mucosa caused by gluten, in genetically susceptible children. It is an important cause of chronic diarrhoea and failure to thrive in children in Pakistan, where wheat (atta) is the main staple and weaning foods are wheat based. Once diagnosed, the treatment is a lifelong gluten-exclusion diet, after which most children grow normally.
Aetiology and predisposing factors
Environmental trigger
- Gluten is a protein in wheat, rye and barley; its gliadin fraction is the harmful part.
- Rice does not contain gluten; pure oats (not contaminated with wheat) are usually tolerated (Nelson).
- Symptoms appear only after gluten enters the diet, so they usually start after weaning onto wheat.
Genetic factors
- Inheritance is polygenic: genetic susceptibility plus gluten exposure.
- Higher risk with certain HLA types: Akbar lists DR3, DR4, DQw2 (DQ2) and B8.
- Family clustering: Akbar notes 2 to 5% of first-degree relatives have symptomatic disease and about 10% have silent mucosal damage.
Associated conditions
| Group | Conditions |
|---|---|
| Autoimmune/endocrine | Type 1 diabetes, autoimmune thyroiditis |
| Chromosomal | Down syndrome (trisomy 21), Turner syndrome |
| Immune | Selective IgA deficiency |
| Skin | Vitiligo, dermatitis herpetiformis |
Children with type 1 diabetes, Down syndrome, Turner syndrome, IgA deficiency or a coeliac sibling should be screened even without gut symptoms.
Frequency
Akbar quotes about 1 in 3000 births; Nelson notes about 1 in 110 people in the United States, most undiagnosed, because serology now picks up mild and silent cases.
Pathogenesis
- Gliadin triggers both T-cell mediated and humoral (IgA) immune responses in the mucosa.
- Antibodies formed include anti-gliadin, anti-reticulin, anti-endomysial and anti-tissue transglutaminase (tTG).
- The surface cells are destroyed, villi become short or flat (villous atrophy) and crypts lengthen (crypt hyperplasia), with lymphocytes and plasma cells in the lamina propria.
- Loss of surface area and brush-border enzymes causes malabsorption (fat, iron, folate, calcium, vitamin D, protein) and secondary lactose intolerance.
Clinical features
Classic (typical) disease
- Onset usually between 6 and 24 months, a few months after wheat-containing foods are introduced; can start at any age.
- Chronic diarrhoea: bulky, pale, foul, fatty stools
- Abdominal distension with wasting of buttocks, thighs and arms
- Failure to thrive, poor appetite, vomiting
- Irritability and unhappiness (often the first thing to improve on diet)
- Ascites or oedema from hypoproteinaemia (Nelson)
- Constipation in a few (from low intake)
"Miserable, pot-bellied, wasted toddler on chapati" = coeliac disease.
Features by system (mostly from malabsorption)
| System | Features | Cause |
|---|---|---|
| Gut | Diarrhoea, distension, vomiting, anorexia, rectal prolapse, aphthous ulcers, intussusception | Mucosal atrophy |
| Blood | Iron-deficiency anaemia (often refractory to oral iron), folate deficiency | Duodenal and jejunal malabsorption |
| Bone and teeth | Rickets, osteoporosis, dental enamel defects | Calcium and vitamin D loss |
| Growth and puberty | Short stature, delayed puberty | Malnutrition |
| Nervous system | Peripheral neuropathy, seizures, ataxia, cerebral calcifications | Vitamin deficiency |
| Skin | Dermatitis herpetiformis, alopecia areata, erythema nodosum | Autoimmune |
| Liver | Mildly raised transaminases that settle on diet | Unclear |
| Lung | Idiopathic pulmonary haemosiderosis | Rare association |
Many children now present without diarrhoea: short stature, anaemia, delayed puberty or raised transaminases. "No diarrhoea" does not exclude coeliac disease.
Spectrum
| Form | Serology | Biopsy | Symptoms |
|---|---|---|---|
| Classic | Positive | Abnormal | Typical gut symptoms |
| Atypical | Positive | Abnormal | Extraintestinal only (short stature, anaemia) |
| Silent | Positive | Abnormal | None (found by screening relatives or high-risk groups) |
| Potential | Positive | Normal | None or minimal |
| Latent | — | Normal now, abnormal at another time on gluten | Variable |
Diagnosis
Diagnosis combines symptoms, antibodies, HLA type and duodenal histology.
Serology
| Test | Point |
|---|---|
| IgA anti-tissue transglutaminase (tTG) | First-line screening test |
| IgA anti-endomysial antibody (EMA) | Highly specific |
| Total serum IgA | Must be checked: IgA deficiency is common in coeliac disease and gives false-negative IgA tests |
| Antigliadin antibodies | Not reliable for screening |
- In the absence of IgA deficiency, anti-tTG or EMA has sensitivity and specificity of about 95% (Akbar, Nelson).
A negative IgA anti-tTG in a child with low total IgA means nothing. Always ask for total IgA with the screen.
Small bowel biopsy
- Done by upper endoscopy (duodenal biopsy) after a positive antibody test; Akbar calls the intestinal biopsy the most reliable test.
- Must be taken while the child is still eating gluten; starting the diet first can heal the mucosa and hide the diagnosis.
- Findings: partial to subtotal villous atrophy, crypt hyperplasia, increased intraepithelial lymphocytes, mucosal inflammation.
Supporting tests
- CBC (iron or folate deficiency), iron studies, calcium, phosphate, vitamin D, total protein and albumin, liver enzymes
- Faecal fat (steatorrhoea), carbohydrate malabsorption
The order is serology first (with total IgA), then biopsy on gluten, then diet. Never start the diet "to see" before the tests.
Differential diagnosis
- Cow's milk or soy protein enteropathy
- Giardiasis (also causes villous atrophy)
- Tropical sprue, bacterial overgrowth
- Cystic fibrosis (pancreatic steatorrhoea; sweat test)
- Crohn disease, eosinophilic gastroenteritis, autoimmune enteropathy
- Primary immunodeficiency, protein-energy malnutrition
Management
Lifelong gluten-exclusion diet
- Remove all wheat, barley and rye and their products, including hidden gluten in processed foods (biscuits, sauces, some sweets).
- Safe starches: rice, maize (corn), potato, soy, tapioca, buckwheat and pure oats (Nelson).
- Akbar defines a gluten-exclusion product as containing under 20 ppm gluten.
- A dietitian and family education are essential, because roti and naan are daily foods in Pakistani homes.
Supportive care in the early phase
- Iron and folate for anaemia; calcium and vitamin D; other vitamins and minerals.
- Temporary lactose restriction for a few weeks while the mucosa heals.
- Extra calories and protein for catch-up growth.
Coeliac crisis
Rarely, a very sick child has profuse diarrhoea, severe malnutrition, oedema, distension and hypokalaemia. Fluid and electrolyte correction is urgent, and corticosteroids may be used only in this setting to speed recovery (Akbar).
Silent and potential disease
- Silent disease (positive serology and abnormal biopsy without symptoms): diet is advised.
- Potential disease (positive serology, normal biopsy): follow up without diet (Akbar).
Response and follow-up
- Mood and appetite improve first, within days to a week; diarrhoea settles and weight rises over a few weeks.
- Histology heals more slowly, over 3 to 12 months (Akbar).
- Antibody levels fall on a strict diet and rise again with gluten exposure, so repeat serology is used to check adherence.
- Monitor growth (height and weight), puberty, haemoglobin and bone health; repeat biopsy only if response is doubtful.
Complications and prognosis
- With strict diet, prognosis is excellent; no harm from a long-term gluten-exclusion diet is recognised.
- Untreated or poorly treated disease: short stature, delayed puberty, osteoporosis, anaemia, and, after many years of disease, malignant lymphoma of the small bowel; strict diet lowers this risk.
- Poor adherence, often in adolescence, is the main cause of continued symptoms.
Expect: gliadin in wheat, rye and barley as the trigger and rice as safe; HLA types (DQ2, DR3); associations with type 1 diabetes, Down and Turner syndromes and IgA deficiency; onset at 6 to 24 months after wheat weaning with diarrhoea, distension, wasting and irritability; atypical presentations (short stature, refractory iron deficiency, dermatitis herpetiformis); IgA anti-tTG with total IgA as the screen; biopsy on gluten showing villous atrophy and crypt hyperplasia; lifelong gluten exclusion; mood improving first and histology taking months; steroids only in coeliac crisis; and small bowel lymphoma as the long-term risk.
Quick revision
- Gliadin (gluten) in wheat, rye, barley; rice, maize, potato are safe.
- HLA DQ2, DR3, DR4, B8; linked to type 1 diabetes, Down, Turner, IgA deficiency.
- Onset 6 to 24 months after wheat weaning; diarrhoea, distension, wasting, irritability.
- Atypical: short stature, anaemia, rickets, delayed puberty, enamel defects.
- Screen: IgA anti-tTG plus total IgA; antigliadin unreliable.
- Biopsy on gluten: villous atrophy, crypt hyperplasia, intraepithelial lymphocytes.
- Lifelong gluten-exclusion diet; iron, folate, vitamin D; short lactose restriction.
- Mood improves first; histology heals in 3 to 12 months; lymphoma risk if untreated.
Written by The House Job from standard references (Basis of Paediatrics by Pervez Akbar; Nelson Essentials of Paediatrics).
FAQ
Why is total IgA checked with the coeliac antibody test?
IgA deficiency is commoner in coeliac disease and makes IgA-based tests falsely negative, so total IgA confirms the result can be trusted.
Can the gluten-exclusion diet be started before the biopsy?
No. The biopsy must be taken while the child is still eating gluten; otherwise the mucosa may heal and the diagnosis can be missed.
Is rice allowed in coeliac disease?
Yes. Rice does not contain gluten, and maize, potato and pure oats are also usually safe.
Is the diet needed for life?
Yes. Symptoms and mucosal damage return on gluten, and strict lifelong avoidance lowers the risk of complications such as lymphoma.