Leukocyte Count and Intracerebral Hemorrhage Expansion.
Acute leukocytosis is a well-established response to intracerebral hemorrhage (ICH). Leukocytes, because of their interaction with platelets and coagulation factors, may in turn play a role in hemostasis. We investigated whether admission leukocytosis was associated with reduced bleeding after acute ICH.



Consecutive patients with primary ICH were prospectively collected from 1994 to 2015 and retrospectively analyzed. We included subjects with a follow-up computed tomographic scan available and automated complete white blood cell count performed within 48 hours from onset. Baseline and follow-up hematoma volumes were calculated with semiautomated software, and hematoma expansion was defined as volume increase >30% or 6 mL. The association between white blood cell count and ICH expansion was investigated with multivariate logistic regression.



A total of 1302 subjects met eligibility criteria (median age, 75 years; 55.8% men), of whom 207 (15.9%) experienced hematoma expansion. Higher leukocyte count on admission was associated with reduced risk of hematoma expansion (odds ratio for 1000 cells increase, 0.91; 95% confidence interval, 0.86-0.96; P=0.001). The risk of hematoma expansion was inversely associated with neutrophil count (odds ratio, 0.90; 95% confidence interval, 0.85-0.96; P=0.001) and directly associated with monocyte count (odds ratio, 2.71; 95% confidence interval, 1.08-6.83; P=0.034). There was no association between lymphocyte count and ICH expansion (odds ratio, 0.96; 95% confidence interval, 0.79-1.17; P=0.718).



Higher admission white blood cell count is associated with lower risk of hematoma expansion. This highlights a potential role of the inflammatory response in modulating the coagulation cascade after acute ICH.
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston. amorotti@mgh.harvard.edu.
Andrea
A
Morotti
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Chia-Ling
CL
Phuah
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Christopher D
CD
Anderson
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Michael J
MJ
Jessel
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Kristin
K
Schwab
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Alison M
AM
Ayres
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Alessandro
A
Pezzini
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Alessandro
A
Padovani
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
M Edip
ME
Gurol
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Anand
A
Viswanathan
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Steven M
SM
Greenberg
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Joshua N
JN
Goldstein
From the Neurology Unit, Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy (A.M., A. Pezzini, A. Padovani); Division of Neurocritical Care and Emergency Neurology, Department of Neurology (A.M., C.-L.P., C.D.A., M.J.J., J.N.G., J.R.), Hemorrhagic Stroke Research Center (A.M., C.-L.P., C.D.A., M.J.J., K.S., A.A., M.E.G., A.V., S.M.G., J.N.G., J.R.), and Department of Emergency Medicine (J.N.G.), Massachusetts General Hospital, Boston.
Jonathan
J
Rosand
D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D006406:Hematoma / Q000097:blood; D006801:Humans; D020300:Intracranial Hemorrhages / Q000097:blood* / Q000000981:diagnostic imaging; D007958:Leukocyte Count; D007964:Leukocytosis / Q000097:blood / Q000209:etiology; D008297:Male; D008875:Middle Aged; D009000:Monocytes; D009504:Neutrophils; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D012737:Sex Factors; D014057:Tomography, X-Ray Computed
hematoma expansion; inflammation; intracerebral hemorrhage; leukocytes; monocytes; neutrophils