SERUM TRANSFERRIN RECEPTOR LEVELS IN PATIENTS UNDERGOING EVALUATION OF IRON STORES - CORRELATION WITH OTHER PARAMETERS AND OBSERVED VERSUS PREDICTED RESULTS

Serum transferrin receptor (sTfR) concentrations were measured in spec imens from 77 patients undergoing serum ferritin determination, and th e results correlated with serum ferritin, serum iron, serum total iron -binding capacity (TIBC) saturation, erythrocyte mean corpuscular volu me (MCV), and mean corpuscular haemoglobin (MCH), All parameters exhib ited the expected inverse correlation with sTfR; this correlation was statistically significant for all parameters except serum iron concent ration. The frequency with which iron deficiency (defined as absence o f stainable marrow iron) is observed in patients with particular ferri tin values in this centre was determined and used to estimate the expe cted number of iron deficient patients in the present study. In no set ting were significantly fewer sTfR levels, 3.05 mu g/ml observed than expected, However, significantly greater than expected numbers of elev ated sTfR values were observed in patients with serum ferritin > 220 m u g/l (P = 0.002). The results suggest that the sTfR lever is probably not useful as a single test for identification of iron deficiency in unselected patients.