Severe Combined Vitamin B12 and Folate Deficiency Presenting With Features Suggestive of Hemolytic Anemia in Two Long-Term Proton Pump Inhibitor Users: A Case Report - Cureus

What the report says

Cureus published a case report describing two middle-aged women who had been using proton pump inhibitors long term and presented with severe, symptomatic macrocytic anemia. According to the report’s abstract, both patients had combined vitamin B12 and folate deficiency and laboratory abnormalities that resembled hemolytic anemia, including very high lactate dehydrogenase levels. The authors framed the cases as an example of how megaloblastic anemia can create diagnostic uncertainty when its biochemical profile overlaps with hemolysis.

The central clinical issue is that vitamin B12 and folate deficiencies disrupt red blood cell production, often producing large, immature blood cells and sometimes causing ineffective blood-cell formation within the bone marrow. That process can raise markers such as LDH and may mimic the pattern physicians look for when evaluating red-cell destruction, potentially complicating the initial workup.

The report links the cases to prolonged proton pump inhibitor use, but the limited publicly available text does not provide the patients’ full medication histories, treatment course, or outcomes. In general medical understanding, long-term acid suppression has been associated with impaired vitamin B12 absorption in some patients because stomach acid helps release B12 from food; folate deficiency may have separate nutritional, gastrointestinal, medication-related, or other causes.

The case report matters because proton pump inhibitors are widely used for acid-related disorders, and severe vitamin deficiency can be missed if clinicians focus only on a hemolysis-like laboratory pattern. The authors’ presentation supports considering nutritional deficiencies in patients with macrocytic anemia and hemolysis-suggestive biomarkers, especially when long-term medication use or other risk factors are present.