Megaloblastic anemia: role of gastric acid in cobalamin malabsorption


"Case Study"

American Journal of BioMedicine  Volume 3, Issue 1, pages14-21, January 2015

Volker Durand; Scott D. Nugues; Joseph Cirach; Maruyama Kondo


Vitamin B12 deficiency is common, and most cases are clinically subtle. We present a case of 75-year-old Indian man with chronic symptoms of gastroesophageal reflux on treatment with antisecretory and H2 antagonist’s medications over 5-years. During last 5-months he had severe vitamin B12 deficiency (serum vitamin B12 18pmol/L, Hb 54 g/L, MCV 108 fL, Platelet 84×109/L). Serum folate was within the normal range at 5.1 ng/mL, and serum creatinine was slightly elevated at 1.5 mg/dL, methylmalonic acid and homocysteine were elevated as a part of vitamin B12-dependent enzyme activity. Further, patient complain from signs and symptoms of B12 deficiency anemia: fatigue, muscle weakness, loss of appetite/weight loss, diarrhea, ataxia, myelopathy and responded well to parenteral vitamin B12 replacement therapy. Based on this evidence, we concluded that patients taking antisecretory and H2 antagonist’s medications for extended periods of time, should be monitored for vitamin B12 status. However, appropriate therapy can lead to complete recovery in up to two-thirds of patients treated.

Keywords: Gastroesophageal reflux; Vitamin B12; antisecretory; H2 antagonist

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