Celiac disease is a chronic, immune-mediated, systemic disorder caused by intolerance to gluten — a protein present in rye, barley, and wheat grains — that affects genetically predisposed individuals.
Due to its wide spectrum of clinical manifestations, celiac disease resembles a multisystemic disorder. Its most common gastrointestinal (GI) symptoms include chronic diarrhea, weight loss, and abdominal distention. However, celiac disease can also manifest in myriad extraintestinal symptoms, ranging from headache and fatigue to delayed puberty and psychiatric disorders, with differing presentations in children and adults.
To date, the only treatment is adopting a gluten-free diet (GFD). Although key to preventing persistent villous atrophy, the main cause of complications in celiac disease, lifelong adherence to GFD is challenging and may not resolve all clinical issues. These shortcomings have driven recent efforts to develop novel therapeutic options for patients with this disease.
Here are five things to know about celiac disease.
1. Rising Prevalence of Celiac Disease and Other Autoimmune Disorders Suggests Environmental Factors May Be at Play
Gluten was first identified as the cause of celiac disease in the 1950s. At that time, the condition was thought to be a relatively rare GI disease of childhood that primarily affected people of European descent, but it is now known to be a common disease affecting those of various ages, races, and ethnicities.
A 2018 meta-analysis found the pooled global prevalence of celiac disease was 1.4%. Incidence has increased by as much as 7.5% annually over the past several decades.
Increased awareness among clinicians and improved detection likely play a role in the trend. However, the growth in celiac disease is consistent with that seen for other autoimmune disorders, according to a 2024 update of evidence surrounding celiac disease. Shared environmental factors have been proposed as triggers for celiac disease and other autoimmune diseases and appear to be influencing their rise, the authors noted. These factors include migration and population growth, changing dietary patterns and food processing practices, and altered wheat consumption.
2. No-Biopsy Diagnosis Is Accepted for Children and Shows Promise for Adults
It is estimated that almost 60 million people worldwide have celiac disease, but most remain undiagnosed or misdiagnosed, or they experience significant diagnostic delays.
Prospective data indicate that children with first-degree relatives with celiac disease are at a significantly higher risk of developing the condition, which should prompt screening efforts in this population.
The 2023 updated guidelines from the American College of Gastroenterology (ACG) state that serology testing plays a central role in screening. This commonly involves serological testing for positive serological markers of the disease, including immunoglobulin A (IgA), anti-tissue transglutaminase IgA (tTG-IgA), anti-deamidated gliadin peptide, or endomysial antibodies.
To confirm diagnosis, clinicians have relied on intestinal biopsy since the late 1950s. The ACG still recommends esophagogastroduodenoscopy with multiple duodenal biopsies for confirmation of diagnosis in both children and adults with suspicion of celiac disease. However, recent years have seen a shift toward a no-biopsy approach.
For more than a decade in Europe, a no-biopsy approach has been established practice in pediatric patients, for whom the burden of obtaining a histological confirmation is understandably greater. Most guidelines now permit children to be diagnosed with celiac disease in the absence of a biopsy under specific circumstances (eg, characteristic symptoms of celiac disease and tTG-IgA levels > 10 times the upper limit of normal). The ACG guidelines state that “this approach is a reasonable alternative to the standard approach to a [celiac disease] diagnosis in selected children.”
The ACG does not recommend a no-biopsy approach in adults, noting that, in comparison with children, there is a relative lack of data indicating that serology is predictive in this population. However, it does recognize that physicians may encounter patients for whom a biopsy diagnosis may not be safe or practical. In such cases, an “after-the-fact” diagnosis of likely celiac disease can be given to symptomatic adult patients with a ≥ 10-fold elevation of tTG-IgA and a positive endomysial antibody in a second blood sample.
A 2024 meta-analysis of 18 studies involving over 12,103 adult patients from 15 countries concluded that a no-biopsy approach using tTG-IgA antibody levels ≥ 10 times the upper limit of normal was highly specific and predictive of celiac disease.