Studies on the Pathogenesis of the Anemia of Hypothyroidism

The blood of 11 adult hypothyroid patients was labeled with radioactive chromium51. The affinity of the erythrocytes for radiochromium in vitro was 54.5 per cent on the average, and the apparent half-life of Cr51-labeled erythrocytes in vivo was 13.8 days—results distinctly different from the normal values of 80 per cent and 24 days previously established in our laboratory. The frequency of anemia in hypothyroidism may be due to the shortened life span of the erythrocytes.