Is There a Role for Duodenal Bulb Biopsies in Celiac Disease Diagnostics?

Diagnosis of Seronegative and Ultrashort Celiac Disease

In its conventional form, celiac disease (CeD) is characterized by both positive serology and flat villi in the duodenum, and is well known by gastroenterologists and general practitioners. The aim of this review was to shed light on 2 neglected and not yet well-defined celiac phenotypes, that is, seronegative and ultrashort CeD. Seronegative CeD can be suspected in the presence of flat villi, positive HLA-DQ2 and/or HLA-DQ8, and the absence of CeD antibodies. After ruling out other seronegative enteropathies, the diagnosis can be confirmed by both clinical and histologic improvements after 1 year of a gluten-free diet. Ultrashort CeD is characterized by the finding of flat villi in the duodenal bulb in the absence of mucosal damage in the distal duodenum and with serologic positivity. Data on the prevalence, clinical manifestations, histologic lesions, genetic features, and outcome of seronegative and ultrashort CeD are inconclusive due to the few studies available and the small number of patients diagnosed. Some additional diagnostic tools have been developed recently, such as assessing intestinal transglutaminase 2 deposits, flow cytometry technique, microRNA detection, or proteomic analysis, and they seem to be useful in the identification of complex cases. Further cooperative studies are highly desirable to improve the knowledge of these 2 still-obscure variants of CeD.

Diagnosis of Celiac Disease: Taking a Bite Out of the Controversy

Celiac disease is a common autoimmune disorder of the small intestine, triggered by an immunological response to the gluten present in wheat, barley, and rye in individuals who are genetically at risk. A key to reducing the complications of this disease is early diagnosis, preferably in childhood, and consuming a lifelong gluten-free diet once diagnosis is confirmed. Yet, the diagnosis of celiac disease is often considerably delayed, exposing patients to needless suffering and morbidity. It is also difficult to confirm histologically if dietary gluten has been restricted prior to obtaining a diagnostic biopsy, a significant problem given the current growing popularity of gluten-free diets. Furthermore, failure to understand or follow current guidelines means physicians may recommend patients commence the gluten-free diet before initiating referral to a gastroenterologist. Finally, adding further confusion, pediatric guidelines in Europe support a diagnosis based on serology rather than on histology, whereas those based in North America do not. The purpose of this review is to discuss these issues and other controversies in the diagnosis of celiac disease and to consider ways to optimize diagnosis across the lifespan.