[Diffuse large B-cell lymphoma expressing high-level glyceraldehyde 3-phosphate dehydrogenase complicated with hypoglycemia].

A 69-year-old male patient was referred to our hospital for further examination of hypoglycemia, splenomegaly, and para-aortic lymphadenopathy. The patient was diagnosed with diffuse large B-cell lymphoma (DLBCL) by para-aortic lymph node biopsy. Hypoglycemia was refractory to glucose supplementation but improved shortly after chemotherapy. This situation suggested that hypoglycemia was caused by lymphoma. We compared the expression levels of glyceraldehyde 3-phosphate dehydrogenase, a glycolytic enzyme whose expression is positively correlated with the glycolytic activity of cells, between the current case and two cases of DLBCL without hypoglycemia to explore the possibility that hypoglycemia was due to intense glucose consumption by lymphoma cells through their high glycolytic activity. Results revealed substantially higher expression levels of glyceraldehyde 3-phosphate dehydrogenase in the current case than in DLBCL without hypoglycemia, suggesting that the glycolytic pathway was enhanced in the current case. These results implied that intense glucose consumption by lymphoma cells through their high glycolytic activity causes hypoglycemia.