The Eosinophil Count Tends to Be Negatively Associated with Levels of Serum Glucose in Patients with Adrenal Cushing Syndrome

BACKGROUND Cushing syndrome is characterized by glucose intolerance, cardiovascular disease, and an enhanced systemic inflammatory response caused by chronic exposure to excess cortisol. Eosinopenia is frequently observed in patients with adrenal Cushing syndrome, but the relationship between the eosinophil count in peripheral blood and indicators of glucose level in patients with adrenal Cushing syndrome has not been determined. METHODS A retrospective study was undertaken of the clinical and laboratory findings of 40 patients diagnosed with adrenal Cushing syndrome at Chungnam National University Hospital from January 2006 to December 2016. Clinical characteristics, complete blood cell counts with white blood cell differential, measures of their endocrine function, description of imaging studies, and pathologic findings were obtained from their medical records. RESULTS Eosinophil composition and count were restored by surgical treatment of all of the patients with adrenal Cushing disease. The eosinophil count was inversely correlated with serum and urine cortisol, glycated hemoglobin, and inflammatory markers in the patients with adrenal Cushing syndrome. CONCLUSION Smaller eosinophil populations in patients with adrenal Cushing syndrome tend to be correlated with higher levels of blood sugar and glycated hemoglobin. This study suggests that peripheral blood eosinophil composition or count may be associated with serum glucose levels in patients with adrenal Cushing syndrome.