Estimation of serum acid proteases at pH 1.8 and pH 3.5 in patients with duodenal ulcer, gastric ulcer and gastric carcinoma.

Using a simple hemoglobin method on the basis of Anson-Mirsky's method, acid protease levels in serum were measured at pH 1.8 (pepsin) and pH 3.5 (gastricsin) in 18 healthy controls and 14 patients with duodenal ulcer, 19 patients with gastric ulcer and 18 patients with gastric cancer. Though acid protease activity in pH 1.8 in duodenal ulcer has a tendency to show a little higher level than healthy controls, there is no significant difference in acid protease levels between controls and each of three diseases.