*AG indicates evidence of chronic atrophic gastritis (low serum pepsinogen [,30 µg/L] in each instance with elevated serum gastrin [.100
pmol/L] in all except no. 8). In a series of 120 consecutive patients (J. Lindenbaum, unpublished data) with proven pernicious anemia (defined as
the presence of antibodies to intrinsic factor and unequivocal evidence of cobalamin deficiency), serum pepsinogen concentrations were less than
30 µg/L in 110 (90.9%), in contrast to 2.5% of 120 normal controls. In the remaining 10 patients with pernicious anemia, serum pepsinogen levels
varied from 30 to 70 µg/L, in the lower half of the normal range. Serum gastrin levels were greater than 100 pmol/L in 105 (87.5%) of the 120
patients with pernicious anemia, in contrast to none of the controls. PA indicates pernicious anemia (serum antibodies to intrinsic factor and low
pepsinogen in each instance, with elevated serum gastrin in all except no. 6); ?AG indicates serum pepsinogen 47 to 67 µg/L, with elevated serum
gastrin only in no. 18. OMEP indicates chronic omeprazole therapy for esophageal reflux; HIST indicates chronic H2-blocker therapy. Diet indicates
inadequate dietary protein intake. IR indicates prior ileal resection.
†Pre indicates pretreatment value; 4 mo indicates value after 4 months of oral cyanocobalamin at 2,000 µg/d.
‡Improved indicates dramatic improvement in neurologic symptoms and cleared indicates complete resolution of symptoms at 4 months.