Leukocytosis in Cushing's syndrome persists post-surgical remission and could predict a lower remission prognosis in patients with Cushing's disease.

CONTEXT: Leukocytosis frequently noted in Cushing's syndrome (CS), along with other blood cell changes caused by direct and indirect cortisol effects.

OBJECTIVE

Assess baseline white blood cell (WBC) profile in CS patients compared to controls and WBC changes pre- and post-remission after surgical treatment for CS.

DESIGN

A comparative nationwide retrospective cohort study.

SETTING

Data from Clalit Health Services database.

PATIENTS: 297 patients (mean age 51 ± 16.1 years, 73.0% women) with CS and 997 age-, sex-, body mass index-, and socioeconomic status-individually matched controls. Ectopic CS or adrenal cancer patients were excluded.

MAIN OUTCOME MEASURE: Mean WBC, neutrophils, and neutrophil-to-lymphocyte ratio (NLR) two-years before and after pituitary or adrenal surgery. WBC and neutrophils are expressed as Kcells/µl.

RESULTS

At baseline, leukocytosis was observed in 21.5% of patients with CS vs. 8.9% of controls (P < 0.001). Patients with CS had significantly higher WBC (8.8 ± 2.88 vs. 7.54 ± 2.45, p < 0.0001), neutrophils (5.82 ± 2.38 vs. 4.48 ± 1.97, p < 0.0001), and NLR (3.37 ± 2.63 vs. 2.27 ± 1.86, p < 0.0001) compared to controls, regardless of pituitary or adrenal source of hypercortisolemia. Post-surgery, patients with CS experienced significant decreases in mean WBC (-0.57 ± 2.56, p < 0.0001), neutrophils (-0.84 ± 2.55, p < 0.0001), and NLR (-0.63 ± 2.7, p < 0.0001). Despite achieving disease remission, patients with CS still had higher WBC (8.11 ± 2.4 vs. 7.46 ± 2.17, p = 0.0004) and neutrophils (4.71 ± 2.10 vs. 4.41 ± 1.87, p = 0.03) compared to controls. Patients with CD and baseline leukocytosis had lower remission rate than those with normal WBC (36.7% vs. 63.9%, p = 0.01).

CONCLUSIONS

At diagnosis, CS patients have elevated WBC, neutrophils, and NLR compared to controls. Remission does not normalize WBC levels in all patients, and baseline leukocytosis predicts a poorer remission prognosis in CD.