Endocrine Abstracts

Background

Suspicion of Cushing´s syndrome (CS) is usually suggested by non-specific clinical data. Chronic hypercortisolism associates changes in white blood cell count (WBC), essentially a higher count with relative lymphopenia. Our purpose is to investigate the prevalence of these findings among a local series of patients with Cushing’s syndrome before and after the hypercortisolism revertion to assess the diagnostic value of these parameters in order to decide who must be evaluated for the disease.

Methods

Data from 34 patients, who underwent surgery for Cushing´s syndrome in our center from 2004 to 2020, were reviewed. The diagnosis of CS was made on the basis of standard clinic and analytical criteria. Urinary free cortisol (UFC), cortisol after 1 mg of dexamethasone (Nugent´s test), and morning cortisol concentrations were collected. WBC baseline parameters were gathered from the blood test preceding diagnosis and 1 month after surgery. We defined relative lymphopenia as <20.5% of WBC, and absolute lymphopenia as < 1300/µL, whereas relative neutrophilia encompassed neutrophils > 65% of WBC, and absolute neutrophilia > 5000/µL.

Results

26 out of the 34 patients were women, and mean age was 49.4 years (range 19-87). The mean baseline UFC levels was 494.8 ± 891.2 µg/24h, Nugent´s test was 24.6 ± 25.8 µg/dl and mean morning cortisol level was 27.2 ± 18.6 mcg/dl. 17 patients had CS due to adrenal causes, 13 were found a pituitary adenoma and 4 an ectopic ATCH production. 76% patients with CS had a relative lymphopenia (mean: 15%) and only 26.4% an absolute lymphopenia. In 82% and 91% patients we found a high absolute (mean: 7065 ± 4958/µl) and relative (mean: 73.8%) neutrophil count respectively. Only 2/34 patients did not have any WBC alterations. After treatment we found an improvement in all WBC lineages with only 11, 7% of patients presenting relative lymphopenia (mean: 34%), 2, 9% absolute lymphopenia (mean: 2927 ± 1720/µl), 44% absolute neutrophilia (mean: 5322 ± 6374 cel/µl), 11, 7% relative neutrophilia (mean: 50%). Results also revealed a correlation between the WBC changes and the markers of CS severity, including UFC and morning serum cortisol.

Conclusions

WBC count may be a useful tool to suggest the evaluation for Cushing´s syndrome in patients with clinical unspecific symptoms like the association of diabetes and abdominal obesity. Specifically as a parameter with negative predictive value in the absence of any WBC alterations.