Non-invasive Screening of Autoimmune Atrophic Gastritis in Asymptomatic Subjects by Serological Biomarker Test (GastroPanel®).

BACKGROUND/AIM: To estimate the prevalence of autoimmune atrophic gastritis (AAG) in the Russian Federation, a systematic screening of asymptomatic healthy adults by non-invasive biomarker testing was conducted. The aim was i) To test the validity of non-invasive serological screening for AAG; ii) to establish the prevalence of AAG among asymptomatic adults. PATIENTS AND METHODS: Altogether, 1,283 asymptomatic, healthy adults (mean age: 38 years) were screened by GastroPanel® test. Those with a biomarker profile indicating AG (n=46) were invited for further examinations; 21 consented to gastroscopy with biopsies classified using the Updated Sydney System and Operative Link to Gastric Atrophy. Blood tests included parietal cell, intrinsic factor and thyroid peroxidase antibodies, and analysis of vitamin B12 and iron. RESULTS: Gastroscopy and biopsies confirmed AG in 20 of the individuals. Parietal cell, intrinsic factor and thyroid peroxidase antibodies were present in five, one and eight individuals, respectively. AAG-associated co-morbidities (iron deficiency and pernicious anemia) were diagnosed in 10 out of 21. The final diagnosis of AAG was made in 15 out of 1,283 subjects (1.2%), of whom four were Helicobacter pylori-positive. When corrected for verification bias (non-attendees in the confirmatory tests; n=25), the adjusted prevalence of AAG was 2.6% (33/1,283). CONCLUSION: AAG prevalence of 2.6% is among the highest reported using non-invasive tests. GastroPanel® is an optimal screening tool, providing the first link in the diagnostic protocol leading to the final diagnosis of this condition. The role of Helicobacter pylori as a trigger of AAG cannot be ruled out.

Quality and best practice in medical laboratories: specific requests for autoimmunity testing.

Special conditions associated with laboratory autoimmune testing are not well compatible with recent developments in regulatory frameworks such as EN/ISO 15189 accreditation or in vitro diagnostic medical device regulation (IVD-R). In addition, international recommendations, guidelines and disease criteria are poorly defined with respect to requirements on autoantibody testing. Laboratory specialists from Austria, Belgium, Croatia, Estonia, Finland, France, Germany, Greece, Hungary, Italy, Norway, Poland, Portugal, South Africa, Spain, Sweden, Switzerland, and The Netherlands collected information, reported national experience, and identified quality issues in relation to autoantibody testing that require consensus on interpretation of the regulatory frameworks and guidelines. This process has been organized by the European Autoimmunity Standardisation Initiative (EASI). By identifying the critical items and looking for a consensus, our objective was to define a framework for, in particular, EN/ISO accreditation purposes. Here, we present a review of current publications and guidelines in this field to unify national guidelines and deliver in this way a European handout on quality control and accreditation for laboratories involved in autoantibody testing. We focus on quality items that can be checked during accreditation visits. Despite various local varieties, we encountered an overwhelming dedication to quality assurance in all contributing countries.