Elevated white blood cell counts in Cushing's disease: association with hypercortisolism

Glucocorticoid receptors are expressed in white blood cells (WBC’s) and are known to play a role in cell adhesion and WBC's recruitment from bone marrow. In Cushing's disease leukocytosis is frequently mentioned as laboratory finding. However, there is no data on the prevalence of this finding among patients, or correlation with disease severity.

To investigate the prevalence of leukocytosis in patients with Cushing's disease, alterations in other blood count parameters and correlation with degree of hypercortisolism.

Data of 26 patients diagnosed and followed for Cushing's disease at our clinic was reviewed. Two patients had disease relapse after complete remission and were studied as 2 separate events.

Of the 26 patients, 17 were women (71 %), with a mean age of 39.8 ± 12.7 years. Mean baseline WBC count was 10,500 ± 2,600 cells/μl and dropped to 8,400 ± 1,900 cells/μl (p < 0.05) after treatment, mean neutrophil count at baseline was 7,600 ± 2,600 cells/μl and dropped to 5,300 ± 1,700 cells/μl (p < 0.05), lymphocyte count was 2,000 ± 600 cells/μl and raised to 2,300 ± 600 cells/μl (p < 0.05), hemoglobin was 13.7 ± 1.2 g/dl and dropped to 12.8 ± 1.4 g/dl (p < 0.05), and platelet number did not change. Elevated WBC count was present in 11/28 cases (40 %). Those patients with normal baseline WBC (mean 9,000 ± 1,500 cells/μl) dropped also to 7,700 ± 1,300 cells/μl after treatment (p < 0. 05). There was a significant positive correlation between decrease in UFC secretion and change in WBC's following treatment (r = 0.67, p < 0.01).

Patients with Cushing's disease present with leukocytosis in approximately 40 % of cases. In most cases, including those without elevated baseline count, the WBC's decreased with disease remission, demonstrating the effect of glucocorticoids on these blood cells.