Advantages of serum pepsinogen A combined with gastrin or pepsinogen C as first-line analytes in the evaluation of suspected cobalamin deficiency: a study in patients previously not subjected to gastrointestinal surgery.

Abstract

Since there is a significant overlap in serum cobalamin concentrations between healthy and cobalamin-deficient individuals, we wanted to compare two different principles for use as supplementary tests to serum cobalamin concentration in patients with suspected cobalamin malabsorption and deficiency. Clinical study of consecutive patients. The catchment area of Sahlgrenska University Hospital, Göteborg. A total of 112 patients with suspected cobalamin deficiency who had not previously undergone gastrointestinal surgery. Gastroduodenoscopy with biopsies taken from the gastric body and the duodenum, Schilling test, and measurement of serum methylmalonic acid (MMA), total homocysteine (Hcy), pepsinogens A and C, and gastrin. Number of patients with gastric body atrophy identified with the combination of MMA and Hcy, and pepsinogen A combined with pepsinogen C or gastrin. About 95% of the patients with severe gastric body atrophy had abnormal concentrations of serum pepsinogen A and/or gastrin or pepsinogen A/C ratio, whereas 65% had abnormal metabolite concentrations. Serum pepsinogen A combined with pepsinogen C identified 100%, and combined with gastrin 88%, of the patients with gastric body atrophy and elevated metabolite tests, and 67 and 75%, respectively, of those who had not yet developed elevated metabolite tests. Pepsinogen A, combined with pepsinogen C or gastrin, should be the first option in evaluating patients with suspected cobalamin deficiency who have not previously undergone gastrointestinal surgery.