Erythrocyte survival in children as studied by labeling with stable 50Cr

The survival of 50Cr- and 51Cr-labeled autologous and/or homologous erythrocytes was compared simultaneously in eight pediatric patients and one adult. 50Cr, a stable, nonradioactive nuclide, had values comparable to those of standard radioactive 51Cr labeling. The data also demonstrated the capability of 50Cr-51Cr labeling to reveal differences in survival between two populations of erythrocytes monitored simultaneously in the same individual. The technique permitted the use of the nonradioactive isotope in volumes of blood that are appropriate for the pediatric age group.