Potential celiac disease (PCD) is a medical classification for individuals who show signs of an immune reaction to gluten but do not yet have the characteristic small intestine damage seen in active celiac disease. While the body mounts an immune response, the intestinal lining has not undergone significant changes. This classification helps healthcare providers identify individuals at risk of developing full celiac disease, enabling proactive monitoring.
Understanding Potential Celiac Disease
Potential celiac disease is distinguished from active celiac disease by specific diagnostic findings. Individuals have positive celiac-specific antibody tests, such as tissue transglutaminase IgA (tTG-IgA) and endomysial antibody (EMA), and sometimes deamidated gliadin peptide (DGP) antibodies.
Despite these positive serology results, a small intestinal biopsy reveals a normal mucosa, meaning there is no villous atrophy, or only minimal changes like an increase in intraepithelial lymphocytes (Marsh grade 0-1). This contrasts with active celiac disease, where the biopsy shows characteristic damage to the villi of the small intestine.
Individuals with potential celiac disease, even if asymptomatic, are at an increased risk of developing active celiac disease over time. This classification guides medical professionals in determining appropriate follow-up strategies. While some may experience symptoms, others remain asymptomatic despite the presence of antibodies. The presence of HLA-DQ2 or HLA-DQ8 haplotypes, genetic markers for celiac disease, often accompanies a diagnosis of potential celiac disease.
Identifying the Signs
Testing for potential celiac disease often occurs due to various symptoms or risk factors. Gastrointestinal symptoms commonly include abdominal pain, bloating, diarrhea, constipation, and nausea. Bloating, for example, appears more common in those with potential celiac disease than in those with active celiac disease.
Non-gastrointestinal symptoms can also prompt testing, including fatigue, anemia (often due to iron deficiency), and bone density issues like osteoporosis or osteomalacia. An itchy, blistering skin rash known as dermatitis herpetiformis can also be a sign. Other signs may include mouth ulcers, headaches, nerve damage, and joint pain. A family history of celiac disease or other autoimmune conditions also increases the likelihood of screening, even if symptoms are mild or absent.
The Diagnostic Process and Next Steps
The diagnostic process for potential celiac disease begins with serologic testing. Blood tests measure specific antibodies, such as tissue transglutaminase IgA (tTG-IgA) and total IgA levels, to check for an immune reaction to gluten. It is important to continue consuming gluten during this initial testing phase to ensure accurate results, as a gluten-free diet can lead to false negatives. If IgA deficiency is present, IgG-based tests like deamidated gliadin peptide (DGP-IgG) or tTG-IgG may be used instead.
If initial blood tests are positive, the next step involves an upper endoscopy with multiple duodenal biopsies. During this procedure, a small camera on a flexible tube examines the upper digestive system, collecting tissue samples from the small intestine. For a diagnosis of potential celiac disease, these biopsies will show either a normal intestinal lining (Marsh grade 0) or only a mild increase in intraepithelial lymphocytes (Marsh grade 1), without villous atrophy. This normal or minimally abnormal biopsy result, combined with positive antibody tests, leads to the classification of potential celiac disease. Healthcare professionals generally recommend continued monitoring for asymptomatic individuals rather than an immediate gluten-free diet.
Monitoring and Future Considerations
Individuals diagnosed with potential celiac disease require ongoing monitoring due to the risk of progression to active celiac disease. The probability of developing overt celiac disease while on a gluten-containing diet is low in children with potential celiac disease; one study indicated only 13% developed active celiac disease over 10 years. Factors that might influence this progression include persistent positive antibody levels, especially tTG2 and EMA, during follow-up. Regular follow-up appointments are important, often involving continued monitoring of symptoms and antibody levels through serologic tests.
While antibody levels may take months to normalize even with a gluten-free diet, they are still used in monitoring. A gluten-free diet is generally not immediately recommended for asymptomatic individuals, as it may not prevent progression. However, if new or worsening symptoms develop, or if subsequent biopsies show villous atrophy, a gluten-free diet would be considered. Long-term management focuses on individualized decisions, considering the presence of symptoms and the risk of progression.