Case for discussion – does this child have coeliac disease?

Question:

A 16-month old child with Down syndrome has been referred to our Department due to chronic, intractable constipation and abdominal distension. Coeliac disease screening was performed earlier: anti-tTG-IgA 0,3 U/ml (negative), IgG-DGP 27 U/ml (normal <10 U/ml) and total IgA 0.34 g/l (lower than normal for age, normal is >0.4g/l).

Rectal biopsy excluded Hirschsprung’s disease. Duodenal biopsies demonstrated Marsh 2 lesion with >20 eosinophils per HPF. Parasitological tests were negative, also skin prick and patch testing, as well as IgE to common nutritive allergens, were negative. A gluten-free diet has been started, weight gain has been observed after 2 weeks but constipation still remains a therapeutic problem, possibly due to other factors (hypotonia, possible concomitant cow’s milk allergy). Therefore cow’s milk protein elimination has been started with a slight improvement in stool consistency.  

Does the child have coeliac disease? Do we need to perform any other test or plan to do the gluten challenge?

Expert answer:

Thank you very much for sharing this interesting case with us.

Children with Down syndrome are at higher risk to develop celiac disease and screening is therefore recommended even in cases without GI symptoms.

In your case, the patient was found to be IgA TGA negative and IgG DGP positive, however in a rather low titre. Total IgA was considered to be lower than normal, however, at early age IgA levels are normally lower and in children at the age 12y 0.2mg/mL (g/L) is usually considered to be a threshold. I am not sure whether Marsh 2 is sufficient to diagnose celiac disease in this scenario. Would be very interested to see patients’ HLA, and if possible TGA deposits in intestinal biopsies. The introduction of GFD improved nutritional status, however, GI symptoms that were a basis for coeliac screening remained, and were attributed to other possible causes. CMP allergy was suspected and the introduction of diet resulted in a slight improvement.

Considering all the data, the coeliac disease should not be considered to be proven. A gluten-free diet is therefore somewhat questionable. You might consider performing HLA status determination and in case of negative results consider an early gluten challenge, controlling for serology and possibly also histology. In the case of HLA positivity, you can discuss two challenge possibilities with parents. Since celiac disease markers were very low, diagnosis is not very likely. Therefore, you can in HLA positive case also propose an early gluten challenge, however, if parents and yourselves are in doubt about the harmful effects of gluten during early childhood, the challenge can be postponed until the age 6-7y, taking into account also a burden of GFD in a patient who will probably be limited by other health-related and social challenges.

If you have any further questions or remarks about this case, you can ask below.