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Published on: March 25, 2016
Diagnosis and outcome of 100 consecutive patients with extreme granulocytic leukocytosis
M T Reding1, J R Hibbs, V A Morrison
1Veterans Affairs Medical Center, Department of Medicine, University of Minnesota, Minneapolis 55417, USA.
Purpose:
To determine the clinical features, causes, and prognostic significance of extreme leukocytosis in adults.
Patients And Methods:
Medical records of 100 consecutive patients who presented at the Minneapolis Veterans Affairs Medical Center between March 1993 and January 1994 with more than 25,000 leukocytes/microL blood and with more than 50% granulocytes were reviewed. Demographic, clinical, and outcome information was recorded, and a cause of extreme leukocytosis was sought in each case.
Results:
Extreme leukocytosis was attributed to infection in 48 cases, advanced malignancy in 13 cases, hemorrhage in 9 cases, glucocorticoids in 8 cases, and other causes in 22 cases. Four patients had previously diagnosed conditions resulting in chronic leukocytosis. Higher leukocyte counts were associated with malignancy (chi2 for trend=12.5, P <0.002). Fever was more common in patients with infection (weighted rate ratio=3.7, 95% Confidence interval [CI]=2.2 to 6.2). Mortality was high overall (31%), and was greater in patients with noninfectious diagnoses compared with infected patients, an association which persisted after stratification by leukocyte count (weighted rate ratio=2.5, 95% CI=1.2 to 4.9).
Conclusion:
Clinicians should be aware that extreme leukocytosis with a predominance of granulocytes is associated with infection in only 48% of cases. The presence of fever increases the likelihood that infection is the cause. Mortality is high, particularly in patients without infection.
