DIAGNOSTIC ACCURACY OF SERUM FERRITIN AND SOLUBLE SERUM TRANSFERRIN RECEPTOR, TAKING BONE MARROW IRON STAIN AS A GOLD STANDARD FOR IRON DEFICIENCY ANEMIA IN HETEROGENOUS GROUP OF PATIENTS
Objective: To determine the diagnostic accuracy of serum ferritin and soluble serum transferrin receptor (sTfR), taking bone marrow iron stain as a gold standard for iron deficiency anaemia in heterogeneous group of patients.
Study Design: Cross-sectional diagnostic accuracy study.
Place and Duration of Study: Department of Diagnostic, Combined Military Hospital Lahore, from Mar to Aug 2020.
Methodology: A total of 55 adult patients, of both genders, undergoing bone marrow examination for any reason were enrolled. Patients with known hemolytic condition (sickle cell anemia, megaloblastic anemia), taking erythropoietin/iron supplements, transfused red cell concentrate (RCC) recently or undergoing chemotherapy were excluded. Age, gender, clinical history and results of bone marrow examination, complete blood count (CBC), serum Ferritin and C-reactive protein (CRP) were recorded.
Results: Serum ferritin was found to be less sensitive (28%) but more specific (100%) for reflecting reduced bone marrow iron stores as compared to sTfR (sensitivity: 60%, specificity: 96.6%). sTfR had highest likelihood ratio (15) and diagnostic accuracy (80%). On Receiver Operator Characteristic (ROC) graph Transferrin index (AUC=0.908) showed maximum accuracy, followed by Ferritin (AUC=0.884) and sTfR (AUC=0.879).
Conclusion: Serum soluble transferring receptor (sTfR) and transferrin index has advantage over serum ferritin alone in predicting the bone marrow iron stores and differentiating iron deficiency anemia from anemia of chronic disease.