Non-Responsive Celiac Disease (NRCD)
Definition
- Persistent symptoms, signs despite 6-12 months dietary gluten avoidance.
- Abnormal tissue transglutaminase (tTG) persists 2-3 years.
Etiology And Differential Diagnosis
| Category | Associated Conditions |
|---|
| Primary Factor | Ongoing inadvertent gluten ingestion. |
| Alternate Villous Atrophy Causes | Autoimmune enteropathy, tropical sprue, medication-induced enteropathy, hypogammaglobulinemia, combined variable immunodeficiency, collagenous sprue, Crohn disease, peptic duodenitis. |
| Celiac-Like Presentations (No Villous Atrophy) | Irritable bowel syndrome (IBS), carbohydrate malabsorption, small intestinal bacterial overgrowth, microscopic colitis. |
| Additional Pathologies | Cow milk protein allergic enteropathy, pancreatic insufficiency. |
Diagnostic Evaluation
- Confirm accuracy of initial celiac disease diagnosis.
- Verify small bowel histology findings consistent with celiac disease.
- Document positive endomysial antibody (EMA), tTG, or deamidated gliadin peptide (DGP) serology during clinical course.
- Confirm presence of human leukocyte antigen (HLA)-DQ2 or HLA-DQ8.
- Note presence of biopsy-proven dermatitis herpetiformis, strong family history, or associated autoimmune disorders.
- Perform expert dietitian evaluation.
- Check celiac serologies; positive testing despite 12 months on gluten-free diet (GFD) indicates ongoing gluten ingestion.
- Obtain small bowel biopsy.
- Add colonic biopsies for persistent diarrhea.
Management
- Implement rigorously supervised strict GFD to resolve ongoing ingestion.
- Adjust diet, monitor progress.
- Treat identified alternative etiologies for ongoing symptoms.
Refractory Celiac Disease (RCD)
Definition And Characteristics
- Persistent, recurrent malabsorptive symptoms, signs.
- Small intestinal villous atrophy present despite strict GFD >12 months.
- Absence of other disorders, overt lymphoma.
- Rare occurrence; scarce evidence for pediatric existence.
- Primarily diagnosed in adults.
Classification
- Subdivided according to intraepithelial lymphocyte (IEL) phenotype.
- Type I RCD: Normal IEL phenotype.
- Type II RCD: Abnormal, clonal intestinal T lymphocytes.
- Type II RCD considered low-grade intraepithelial lymphoma.
- Type II RCD carries poor prognosis.
Pathophysiology And Diagnosis
- Rigorously exclude other NRCD causes (Crohn disease, autoimmune enteropathy, small bowel bacterial overgrowth, cow milk protein allergy, pancreatic insufficiency) before confirming true RCD.
- Identify abnormal intestinal lymphocytes via immunohistochemistry of IELs.
- Utilize flow cytometry demonstrating increased CD3-positive cells lacking CD8.
- Identify clonal T-cell receptor gene rearrangement via molecular analysis.