RBP4 and Cushing syndrome due to macronodular adrenal hyperplasia: We found that the concentration of fetuin A was lower, while FABP4 and RBP4 concentrations were higher in Cushing’s syndrome compared to controls [156.4 ± 60.0 μg/ml vs 260.7 ± 49.6 μg/ml; 79.8 (35.2-156.1) ng/ml vs 27.9 (17.1-36.7) ng/ml and 34 (30-37.7) mg/l vs 25.8 (23.6-27.7) mg/l, respectively].