Do all the patients with gastric parietal cell antibodies have pernicious anemia?

Objective This study evaluated whether all the patients with serum gastric parietal cell antibody ( GPCA ) positivity had pernicious anemia ( PA ). Materials and Methods The blood hemoglobin ( H b), iron, and vitamin B 12 concentrations, and mean corpuscular volume ( MCV ) in 124 GPCA ‐positive patients were measured and compared with the corresponding data in 124 age‐ and sex‐matched healthy controls. PA was defined by World Health Organization ( WHO ) as having an H b concentration < 13 g dl −1 for men and < 12 g dl −1 for women, an MCV ≥ 100 fl, and a serum vitamin B 12 level < 200 pg ml −1 . Results We found that 20, 25, and 20 GPCA ‐positive patients had deficiencies of H b (men < 13 g dl −1 , women < 12 g dl −1 ), iron (<60 μg dl −1 ), and vitamin B12 (<200 pg ml −1 ), respectively. Moreover, 16 GPCA ‐positive patients had abnormally high MCV (≥100 fl). GPCA‐positive patients had a significantly higher frequency of H b, iron, or vitamin B 12 deficiency and of abnormally high MCV (all P‐ values < 0.001) than healthy controls. However, only 12.9% of 124 GPCA ‐positive patients were diagnosed as having PA by the WHO definition. Conclusion Only 12.9% of GPCA‐positive patients are discovered to have PA by the WHO definition.