Evaluation of reticulocyte hemoglobin for assessment of anemia in rheumatological disorders

OBJECTIVE: The aim of this study was to evaluate the role of reticulocyte hemoglobin (Ret He) estimation in subtyping of anemia and to find the correlation of Ret He with the severity of anemia. METHODS: Ninety-four patients with rheumatic diseases with anemia were enrolled. Blood samples were taken to determine various parameters. Patients were divided into three groups: iron deficiency anemia, anemia of chronic disease with iron deficiency and anemia of chronic disease depending on the iron status and inflammatory markers. Analysis of variance and Pearson correlation coefficient were used. Receiver operating characteristic analysis was used to evaluate the accuracy of the parameters in differentiating anemia. RESULTS: Statistically significant differences among groups were seen with regard to parameters such as erythrocyte sedimentation rate, C-reactive protein, serum ferritin, total iron binding capacity, transferrin saturation, transferrin receptor protein, soluble transferrin receptor/log ferritin and Ret He. Ret He correlates with the subtype of anemia in patients with rheumatic disorders but it does not correlate with the severity of anemia. Soluble transferrin receptor/log ferritin, Ret He and serum ferritin values were the best parameters to differentiate between various groups. Ret He (pg) values of 26.5, while serum ferritin levels (µg/L) of 178 were highly sensitive and specific for iron deficiency anemia, anemia of chronic disease with iron deficiency and anemia of chronic disease groups, respectively. CONCLUSION: In cost constraints settings, a simple investigation like Ret He alone or with serum ferritin can help us to diagnose and differentiate between the different types of anemia accompanying rheumatological disorders without doing other serum iron studies and expensive tests like transferrin receptor protein which are not readily available.