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

Background: 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.

Goals: 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.

Study: 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).

Results: 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).

Conclusions: 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.