Histology in children and adults with suspected coeliac disease (CD)
| Children | Adults | |
|---|---|---|
| Is a biopsy necessary for diagnosis? | Dependent on TG2 level, HLA status—if anti-TG2 titres are high (>10 times the upper limit of normal), the ESPGHAN guidelines have an option to diagnose CD without duodenal biopsies by applying a strict protocol with further laboratory tests.15 | Recommendation for biopsy—all guidelines emphasise the combined use of biopsy and serological analyses for diagnosis.16 17 138 139 However, in low-resource countries, a positive TG2 with symptom improvement on a GFD may be considered sufficient for diagnosis.138 139 |
| How many biopsies? And where from? | 4–6 including 2 from bulb, as focality was present in 18%, patchiness in 53% and at least 1 normal biopsy fragment was present in 36% of the cases. Sometimes, changes compatible with CD are only seen in the bulb,140 11% of patients show only duodenal bulb involvement, and also bulb sparing, so both should be taken.141 | At least four, including bulb biopsy.16 141 |
| Adherence to guidelines for biopsy? | In those without histological evidence of CD, fewer biopsies are obtained with none documented from the bulb. Failure to take the recommended number of biopsies could result in some missed cases of CD.142 | Adherence to submitting ≥4 specimens is low in the USA. Adherence yields a doubling of the diagnostic rate of CD.143 |
| Intraepithelial lymphocytes/100 enterocytes. What is the cut-off count? | Normal architecture with increased IELs is considered non-specific in paediatric guidelines.15 | Normal architecture with ≥25 IELs/100 enterocytes has been validated as a cut-off point in adults.16 144 |
GFD, gluten-free diet; IEL, intraepithelial lymphocyte; TG2, transglutaminase 2.