A laboratory score in the diagnosis of autoimmune atrophic gastritis: a prospective study.

Several biomarkers have been proposed for the diagnosis of autoimmune atrophic gastritis (AAG), but at the present there is no appropriate testing strategy for the disease. The aim of this study was to develop and validate a laboratory score able to address the diagnosis of AAG in a general practice setting. We prospectively evaluated a number of serum biomarkers (vitamin B12, mean corpuscular volume, hemoglobin, gastrin, and chromogranin A levels) in a case-control population and built 2 biochemical scores, the first with all the parameters [Global Score (GS)], and the second as the best statistical combination of them [Simple Score (SS)]. In the second phase we validated the score that proved to be more efficient on a random population referred to our center (Gastroenterology Outpatient Clinic). Both models turned out to be reliable in detecting patients with suspected AAG, showing excellent accuracy [area under the receiver operating curve (AUC-ROC) 0.94; 95% confidence interval (CI), 0.91-0.97 for GS and AUC-ROC 0.93; 95% CI, 0.89-0.86 for SS]. The SS proved to be more convenient because of its accessibility and availability in a general setting and its low cost. The validation of the SS showed a sensitivity of 85.7% (95% CI, 57.2-98.2) and a specificity of 83.7% (95% CI, 74.2-90.89). Herein, we describe 2 nonexpensive and reliable score models, particularly the SS, that can be applied in daily medical practice for identifying patients potentially affected by AAG.