Histologic features in an autoimmune gastritis patient with hypergastrinemia: Call for a grading system for G cell hyperplasia

Abstract

Abstract Introduction/Objective Autoimmune gastritis (AG) is characterized by oxyntic glands destruction, metaplasia, enterochromaffin-like endocrine cell abnormality and G-cell hyperplasia with hypergastrinemia. The gastrin level can be extraordinarily high in certain cases to justify suspicion of Zollinger-Ellison syndrome. We herein report one such case and discuss clinical implication of a grading system for G-cell hyperplasia to correlate histology with gastrin levels. Methods/Case Report The patient was a symptomatic 65 year-old female with hypergastrinemia (2,068 pg/mL), negative abdomen/pelvis CT scan, positive anti-intrinsic factor and anti-parietal cell antibodies. Under esophagogastroduodenoscopy, biopsies were obtained from gastric cardia, fundus, corpus, incisura angularis, and antrum. Morphology and immunostains confirmed autoimmune gastritis. Diffuse linear pattern G-cell hyperplasia was evident in antrum and incisura angularis, counting up to 200 G-cells per linear millimeter. One study defined G-cell hyperplasia as >140 gastrin-positive cells per linear millimeter while another proposed a 2-tier stratification, i.e., simple hyperplasia (4-5 cells for each gland) and linear hyperplasia (continuous chain-like distribution of G-cells). Such scoring, however, was largely qualitative and fell short in delineating the extent of G-cell hyperplasia and correlation with gastrinemia. Results (if a Case Study enter NA) NA Conclusion Lack of G-cell grading system hindered our unequivocal determination of the G-cell hyperplasia as underlying or contributing cause of hypergastrenemia. The unique features of our case highlighted the necessity for installing a practical grading system that incorporates G-cell density, pattern (linear vs. nodular), extent of involved areas, other features of AG to correspond to gastrin level. With accumulation of clinical information, one such grading system is feasible and will improve our knowledge and patient care.