Anemia and hematinic deficiencies in gastric parietal cell antibody-positive and -negative oral mucosal disease patients with microcytosis

Background/Purpose Microcytosis is defined as mean corpuscular volume (MCV) < 80 fL. This study assessed the anemia statuses and hematinic deficiencies in 30 patients with gastric parietal cell antibody-positive microcytosis (GPCA+/microcytosis) and 210 patients with GPCA-negative microcytosis (GPCA−/microcytosis). Methods We measured and compared the mean red blood cell (RBC) count, MCV, and RBC distribution width (RDW), as well as blood levels of hemoglobin, iron, vitamin B12, folic acid, and homocysteine among the aforementioned patient groups and 240 healthy controls. Results Compared with GPCA−/microcytosis, the positive counterparts presented with a lower mean serum vitamin B12 level (marginal significance), significantly higher mean RDW and serum homocysteine level, and significantly greater frequencies of vitamin B12 deficiency and high homocysteine level. GPCA−/microcytosis patients had significantly greater frequencies of hemoglobin, iron, vitamin B12, and folic acid deficiencies and of RBC count > 5 × 10 ¹² /L than healthy controls. Moreover, 19 of 30 GPCA+/microcytosis patients and 143 of 210 GPCA−/microcytosis patients had anemia, with iron deficiency anemia being the most common type, followed by thalassemia trait-induced anemia and microcytic anemia due to other causes. Conclusion We conclude that GPCA in microcytosis patients' sera may have caused significantly lower mean vitamin B12 level as well as significantly higher mean RDW and serum homocysteine level in our GPCA+/microcytosis patients than in GPCA−/microcytosis patients. Herein, iron deficiency anemia was the most common type of anemia in anemic GPCA+/microcytosis and GPCA−/microcytosis patients.