Beyond symptomatology: A comparative analysis of unilateral and bilateral macronodular mild autonomous cortisol secretion

Objective

To investigate the clinical, laboratory findings and signal intensity index (SII) on magnetic resonance imaging (MRI) of patients with bilateral and unilateral macronodular mild autonomous cortisol secretion (MACS).

Patients and Measurements

Clinical and laboratory findings of 81 patients with MACS were examined from retrospective records. SII of adenomas and internodular areas were evaluated by MRI. The unilateral group included patients with an adrenal macronodule (≥1 cm) in a single adrenal gland, while the bilateral group included patients with at least one macronodule in both adrenal glands.

Results

In total, 46 patients were in the unilateral (57%), while 35 (43%) patients were in the bilateral groups. The dehydroepiandrosterone sulphate (DHEA-S) level was lower in the unilateral than in the bilateral group (p < .001). The presence of type 2 diabetes mellitus (T2DM), glycosylated haemoglobin (HbA1c) and low-density lipoprotein (LDL) concentrations were higher in the bilateral group (p < .05). However, no significant difference was detected in terms of adrenocorticotropic hormone (ACTH) and overnight 1 mg dexamethasone suppression test (DST) between the two groups (p > .05). There was no difference in SII between adenomas within the same patient, as well as between the unilateral and bilateral groups (p > .05). Logistic regression analysis based on the differentiation between unilateral and bilateral macronodular MACS demonstrated that DHEA-S, HbA1c and LDL concentrations were associated factors.

Conclusion

DHEA-S levels may not be as suppressed in patients with bilateral macronodular MACS as compared to those with unilateral adenoma. T2DM and hypercholesterolaemia have a higher frequency in bilateral patients. However, ACTH, overnight 1 mg DST and SII may not provide additional information for differentiation of bilaterality and unilaterality.