Measurement of erythrocyte creatine might be useful for diagnosing latent hemolysis.

OBJECTIVES

Whereas HbA1c values are low relative to glycemia in patients with hemolytic anemia, including compensatory anemia, low HbA1c levels along with negative results for conventional hemolysis indicators have been reported in patients with latent hemolysis. Conversely, glycated albumin (GA) is a glycemic control indicator unaffected by hemolysis. Erythrocyte creatine (EC) is a hemolysis indicator that reflects the mean age of red blood cells (M). We recently reported a formula for obtaining M based on EC. The present study examined the usefulness of EC measurements and M calculated with EC for diagnosing latent hemolysis.

MATERIALS AND METHODS

Two patients with latent hemolysis and low HbA1c values relative to glycemia were investigated, while controls comprised 214 patients (including patients with hemolysis and/or type 2 diabetes mellitus). HbA1c was expressed in International Federation of Clinical Chemistry and Laboratory Medicine (IFCC) units (iA1c). GA/iA1c ratios, reticulocyte counts, EC, and M in patients with latent hemolysis were compared to non-hemolysis, compensatory hemolysis, and hemolytic anemia patients.

RESULTS

Both reticulocyte counts and haptoglobin levels were within reference ranges in patients with latent hemolysis. GA/iA1c ratios and EC were higher than reference values in patients with latent hemolysis, and M values were 41.6 and 48.4 days, respectively, shorter than the reference range (49.1-66.8 days).

CONCLUSIONS

EC measurement and M values calculated on the basis of EC might be useful for diagnosing latent hemolysis.