CAUSES for anacidity in various forms of gastric disease have constituted the basis for numerous studies, and different conclusions have been reached. Such studies go back many years. Among the earlier workers were Ewald,1 who observed complete anacidity in the presence of total atrophy of the gastric mucosa, and Einhorn,2 who recognized anacidity as a functional nervous disorder. Martius3 visualized it as a congenital defect.
Among the more outstanding proponents of chronic gastritis as the major cause of true anacidity were Faber4 and his co-workers. Faber determined that ranges of gastric acidity coincided excellently with anatomic changes observable through anatomic investigations of gastritis. "Anacidity is certainly a natural consequence in the severe atrophic forms, but in the less advanced cases we cannot estimate the degree of secretion disturbance from the anatomic picture."
That other influences may be involved as causes in some cases of true achlorhydria
GUISS LW, STEWART FW. HISTOLOGIC BASIS FOR ANACIDITY IN GASTRIC DISEASE. Arch Surg. 1948;57(5):618-623. doi:10.1001/archsurg.1948.01240020627002