Section 2 Diagnosis

**23**

**Chapter 2**

**Abstract**

**1. Introduction**

Challenges with Point-Of-Care

Tests (POCT) for Celiac Disease

Current screening test for celiac disease involves blood test in centralized pathol-

ogy laboratories, typically performing enzyme-linked immune-sorbent assays (ELISA) to detect specific celiac disease antibodies. Most of the current available celiac disease antibody tests detect anti-gliadin (AGA), anti-endomysial (EMA), anti-transglutaminase (tTG), or deamidated gluten peptide (DGP) antibodies from serum or whole blood samples. It requires blood collection from untreated celiac patients, which is often invasive and inconvenient. There is a rapid growth in demand for noninvasive celiac tests for the early and fast diagnosis of celiac disease to help potential celiac patients obtain results and take corresponding actions. Over the last decade, several point-of-care tests (POCT) have been introduced to the market, but these tests have not been widely accepted by clinicians. Moreover, the 2009 NICE guideline CG 86 recommended that self-tests and/or POCT for celiac disease should not be used as a substitute for laboratory-based tests. Here, we provide a background on the evolution of POCT for celiac disease. We discuss general principle of operation for the known commercial kits as well as the use of various antigens and antibodies in different tests developed over the years. Finally, we discuss challenges for future research directions in celiac disease POCTs.

**Keywords:** celiac disease, point-of-care tests, lateral flow test, immunoassays

Celiac disease is defined as a lifelong condition as a result of ingestion of gluten among genetically susceptible people that can be relieved by the introduction of gluten-free diet; the condition relapses with gluten intake [1]. Recent studies show that it is prevalent around the world, covering from the western world, such as Europe and America, to Oceania, Africa, and Asia. The number of celiac sufferers increases, doubling its number every two decades [2]. The symptoms vary at a wide range, from flatulence, constipation, anorexia, irregular bowel habits, and irritability to numbness in limbs, foggy mind, diarrhea, and depression [3]. Therefore, it is hard to recognize the condition and deliver the diagnosis. In fact, almost 90% of celiac patients remain undiagnosed, due to the nonspecific or absent symptoms over a long period [4]. Thereby, it is of paramount significance to achieve the early-stage diagnosis of celiac disease that can lead to improving the patients' quality of life. The current gold standard of celiac disease diagnosis, which has been also developed in a much earlier period, is to observe the small intestine atrophy obtained

*Huan Wu, Michael Wallach and Olga Shimoni*
