Coexistence of diabetes and phosphofructokinase deficiency.

OBJECTIVE

To report the first case of coexisting diabetes mellitus and phosphofructokinase deficiency.

METHODS

We describe a 50-year-old woman who had a history of diabetes mellitus, muscle weakness, and mild hemolysis. Phosphofructokinase deficiency was diagnosed with use of the ischemic forearm exercise test and magnetic resonance spectroscopy during exercise.

RESULTS

The presence of phosphofructokinase deficiency affected the methods of follow-up and choices of diabetes therapy. Insulin therapy was avoided because insulin may exacerbate muscle weakness by suppressing production of free fatty acids. Strenuous exercise had to be avoided as well because it may induce myoglobinuria in patients with phosphofructokinase deficiency. Glycosylated hemoglobin measurements could not be used because they were falsely low (from hemolysis), and other indicators of long-term glycemic control were utilized instead.

CONCLUSION

Diabetes mellitus and phosphofructokinase deficiency can coexist. In such cases, choices of diabetes therapy and methods of monitoring of glycemic control must be adjusted to account for the presence of phosphofructokinase deficiency.