Endocrine Abstracts

Background: The circulating inflammatory markers and cytokines are associated with unfavorable cardiovascular and metabolic outcomes in patients with primary hypertension. Few reports demonstrated that some adrenal tumors can produce various markers of inflammation, acute phase protein and cytokines, contributing to hemodynamic and metabolic disturbances.

Objective: We aimed to study the differences in the levels of inflammatory parameters and interleukin-6 (IL-6) in adrenal tumors, and their effects to clinical presentations and outcomes.

Methods: We prospectively collected the data of 20 patients with primary aldosteronism (PA), 20 patients with pheochromocytoma (PHEO), 8 patients with mild autonomous cortisol excess and 8 patients with non-functioning adrenal adenoma in Siriraj hospital. The demographic and clinical data, radiographic finding, hormonal status, intraoperative and postoperative outcomes, and follow-up data were evaluated in this study. Inflammatory markers (complete blood count, c-reactive protein (CRP), prealbumin) and IL-6 were measured in all patients, and compared between each group.

Results: Patients with PHEO had significantly higher IL-6 levels than those with other adrenal tumors (4.4 vs 2 pg/ml, P=0.003). 8/20 (40%) of patients with PHEO had elevated of IL-6 than normal reference range. Of these patients with IL-6 secreting PHEO, 50% had history of unexplained fever, 88% had weight loss, and all patients had anemia. Only two patients with PA had mild elevation of IL-6, and no systemic inflammatory manifestation was demonstrated in these patients. Median size of IL-6 secreting PHEOs were larger than non-IL-6 secreting PHEO (11 cm vs 5.4 cm, P=0.1). Patients with PHEO had lowest prealbumin levels (P=0.004). No significant difference in CRP levels and white blood count levels was found among adrenal tumors. Diabetes was seen in 13(65%) patients with PHEO and significantly higher than other groups (P<0.001). Hospital length of stay after surgical resection was significantly longer in patients with IL-6 secreting PHEO (20 days vs 8 days, P=0.008). Postoperatively, IL-6 levels gradually returned to normal.

Conclusions: Adrenal tumors, especially PHEO, had the elevation of inflammatory markers and IL-6, and subsequently produced systemic inflammatory response and increased postoperative complications.