Research Paper|Volume 12, Issue 9|pp 8702—8709

A novel method for calculating mean erythrocyte age using erythrocyte creatine

Masashi Kameyama¹, Masafumi Koga², Toshika Okumiya³

¹Department of Diagnostic Radiology, Tokyo Metropolitan Geriatric Hospital and Institute of Gerontology, Tokyo, Japan
²Department of Internal Medicine, Hakuhokai Central Hospital, Hyogo, Japan
³Department of Biomedical Laboratory Sciences, Faculty of Health Sciences, Kumamoto University, Kumamoto, Japan

Received: February 23, 2020Accepted: April 20, 2020Published: May 11, 2020

Copyright © 2020 Kameyama et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY 3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Abstract

Estimating the lifespan of erythrocytes is useful for the differential diagnosis of anemia. However, measuring the lifespan of erythrocytes was very difficult; therefore, it was seldom measured. Erythrocyte creatine (EC) decreases reflecting erythrocyte age. We developed a method to obtain mean erythrocyte age (M_RBC) from EC.

We reanalyzed the previously published data from 21 patients with hemolytic anemia, which included EC and the half-life of ⁵¹Cr.

M_RBC and log_e EC showed excellent significant linearity (r = −0.9475, p < 0.001), proving that it could be treated as a mono-exponential relationship within the studied range (EC: 1.45 – 11.76 μmol/g Hb). We established an equation to obtain M_RBC (days) from EC (μmol/g Hb): M_RBC = −22.84log_e EC + 65.83.

This equation allowed calculation of M_RBC based on EC which has practical applications such as the diagnosis of anemia.