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High natural killer cell number might identify stroke patients at risk of developing infections.

De Raedt S, De Vos A, Van Binst AM, De Waele M, Coomans D, Buyl R, De Keyser J - Neurol Neuroimmunol Neuroinflamm (2015)

Bottom Line: We found that the number of circulating natural killer (NK) cells within the first hours after stroke was higher in stroke patients who developed infections (mean 435 cells/mL; 95% confidence interval [CI] 321-588) than in stroke patients who did not develop infections (mean 236 cells/mL; 95% CI 186-300; p = 0.001).These findings all remained significant after adjustment for age and stroke volume.These findings need to be validated in larger studies.

View Article: PubMed Central - PubMed

Affiliation: Departments of Neurology (S.D.R., A.D.V., J.D.K.), Radiology (A.-M.V.B.), Hematology (M.D.W.), and Biostatistics and Medical Informatics (D.C., R.B.), Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (VUB), Brussels, Belgium; and Department of Neurology (J.D.K.), Universitair Medisch Centrum Groningen, the Netherlands.

ABSTRACT

Objective: To investigate early changes in leukocyte subsets and autonomic function as predictors of the development of poststroke infections.

Methods: We assessed the time course of leukocyte subsets in the blood of 59 patients with acute ischemic stroke. We divided the patients into 2 groups: those who developed infections during the first 7 days after stroke onset and those who did not. We measured urinary norepinephrine and epinephrine concentrations and pulse rate variability indices within 24 hours of admission.

Results: We found that the number of circulating natural killer (NK) cells within the first hours after stroke was higher in stroke patients who developed infections (mean 435 cells/mL; 95% confidence interval [CI] 321-588) than in stroke patients who did not develop infections (mean 236 cells/mL; 95% CI 186-300; p = 0.001). This was followed by a decrease in all lymphocyte subsets from admission to day 1, varying between 22% and 40%, which was not seen in patients without poststroke infection (mean increase varied between 2% and 23%; all p < 0.005). In the group that developed infections, pulse rate variability revealed a decreased high frequency component. These findings all remained significant after adjustment for age and stroke volume.

Conclusions: High circulating NK cell count within the first hours after ischemic stroke onset followed by a drop in all lymphocyte subsets identified patients who developed infections and may be caused by a sympathovagal imbalance with sympathetic overweight. These findings need to be validated in larger studies.

No MeSH data available.


Related in: MedlinePlus

Time course of C-reactive protein (CRP) and leukocyte subsets in patients with and without poststroke infections (PSI)Values are expressed as means ± 95% confidence interval. Solid lines show the time course of unadjusted means, dashed lines show the means assuming a 74-year-old with a stroke volume of 5 mL. The dotted line depicts the mean value in healthy individuals. *p < 0.05, **p < 0.01, ***p < 0.005, PSI vs no PSI, unadjusted/adjusted, t test (unadjusted), analysis of covariance (adjusted). NCRP (PSI): admission (adm) = 24, day 1 = 23, day 2 = 16, day 3 = 18, day 7 = 19; NCRP (no PSI): adm = 35, day 1 = 34, day 2 = 26, day 3 = 26, day 7 = 22; Nleukocyte subsets (PSI): adm = 24, day 1 = 21, day 2 = 20, day 3 = 19, day 7 = 17; Nleukocyte subsets (no PSI): adm = 34, day 1 = 32, day 2 = 29, day 3 = 30, day 7 = 22.
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Figure 1: Time course of C-reactive protein (CRP) and leukocyte subsets in patients with and without poststroke infections (PSI)Values are expressed as means ± 95% confidence interval. Solid lines show the time course of unadjusted means, dashed lines show the means assuming a 74-year-old with a stroke volume of 5 mL. The dotted line depicts the mean value in healthy individuals. *p < 0.05, **p < 0.01, ***p < 0.005, PSI vs no PSI, unadjusted/adjusted, t test (unadjusted), analysis of covariance (adjusted). NCRP (PSI): admission (adm) = 24, day 1 = 23, day 2 = 16, day 3 = 18, day 7 = 19; NCRP (no PSI): adm = 35, day 1 = 34, day 2 = 26, day 3 = 26, day 7 = 22; Nleukocyte subsets (PSI): adm = 24, day 1 = 21, day 2 = 20, day 3 = 19, day 7 = 17; Nleukocyte subsets (no PSI): adm = 34, day 1 = 32, day 2 = 29, day 3 = 30, day 7 = 22.

Mentions: PSI was associated with an increased CRP, increased neutrophil and monocyte counts, and a decreased lymphocyte count (figure 1). These associations remained after exclusion of outliers. After adjustment for age and stroke volume, increased CRP on days 2 and 3 and neutrophilic count on days 1, 2, and 3 remained significant (figure 1).


High natural killer cell number might identify stroke patients at risk of developing infections.

De Raedt S, De Vos A, Van Binst AM, De Waele M, Coomans D, Buyl R, De Keyser J - Neurol Neuroimmunol Neuroinflamm (2015)

Time course of C-reactive protein (CRP) and leukocyte subsets in patients with and without poststroke infections (PSI)Values are expressed as means ± 95% confidence interval. Solid lines show the time course of unadjusted means, dashed lines show the means assuming a 74-year-old with a stroke volume of 5 mL. The dotted line depicts the mean value in healthy individuals. *p < 0.05, **p < 0.01, ***p < 0.005, PSI vs no PSI, unadjusted/adjusted, t test (unadjusted), analysis of covariance (adjusted). NCRP (PSI): admission (adm) = 24, day 1 = 23, day 2 = 16, day 3 = 18, day 7 = 19; NCRP (no PSI): adm = 35, day 1 = 34, day 2 = 26, day 3 = 26, day 7 = 22; Nleukocyte subsets (PSI): adm = 24, day 1 = 21, day 2 = 20, day 3 = 19, day 7 = 17; Nleukocyte subsets (no PSI): adm = 34, day 1 = 32, day 2 = 29, day 3 = 30, day 7 = 22.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4335818&req=5

Figure 1: Time course of C-reactive protein (CRP) and leukocyte subsets in patients with and without poststroke infections (PSI)Values are expressed as means ± 95% confidence interval. Solid lines show the time course of unadjusted means, dashed lines show the means assuming a 74-year-old with a stroke volume of 5 mL. The dotted line depicts the mean value in healthy individuals. *p < 0.05, **p < 0.01, ***p < 0.005, PSI vs no PSI, unadjusted/adjusted, t test (unadjusted), analysis of covariance (adjusted). NCRP (PSI): admission (adm) = 24, day 1 = 23, day 2 = 16, day 3 = 18, day 7 = 19; NCRP (no PSI): adm = 35, day 1 = 34, day 2 = 26, day 3 = 26, day 7 = 22; Nleukocyte subsets (PSI): adm = 24, day 1 = 21, day 2 = 20, day 3 = 19, day 7 = 17; Nleukocyte subsets (no PSI): adm = 34, day 1 = 32, day 2 = 29, day 3 = 30, day 7 = 22.
Mentions: PSI was associated with an increased CRP, increased neutrophil and monocyte counts, and a decreased lymphocyte count (figure 1). These associations remained after exclusion of outliers. After adjustment for age and stroke volume, increased CRP on days 2 and 3 and neutrophilic count on days 1, 2, and 3 remained significant (figure 1).

Bottom Line: We found that the number of circulating natural killer (NK) cells within the first hours after stroke was higher in stroke patients who developed infections (mean 435 cells/mL; 95% confidence interval [CI] 321-588) than in stroke patients who did not develop infections (mean 236 cells/mL; 95% CI 186-300; p = 0.001).These findings all remained significant after adjustment for age and stroke volume.These findings need to be validated in larger studies.

View Article: PubMed Central - PubMed

Affiliation: Departments of Neurology (S.D.R., A.D.V., J.D.K.), Radiology (A.-M.V.B.), Hematology (M.D.W.), and Biostatistics and Medical Informatics (D.C., R.B.), Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel (VUB), Brussels, Belgium; and Department of Neurology (J.D.K.), Universitair Medisch Centrum Groningen, the Netherlands.

ABSTRACT

Objective: To investigate early changes in leukocyte subsets and autonomic function as predictors of the development of poststroke infections.

Methods: We assessed the time course of leukocyte subsets in the blood of 59 patients with acute ischemic stroke. We divided the patients into 2 groups: those who developed infections during the first 7 days after stroke onset and those who did not. We measured urinary norepinephrine and epinephrine concentrations and pulse rate variability indices within 24 hours of admission.

Results: We found that the number of circulating natural killer (NK) cells within the first hours after stroke was higher in stroke patients who developed infections (mean 435 cells/mL; 95% confidence interval [CI] 321-588) than in stroke patients who did not develop infections (mean 236 cells/mL; 95% CI 186-300; p = 0.001). This was followed by a decrease in all lymphocyte subsets from admission to day 1, varying between 22% and 40%, which was not seen in patients without poststroke infection (mean increase varied between 2% and 23%; all p < 0.005). In the group that developed infections, pulse rate variability revealed a decreased high frequency component. These findings all remained significant after adjustment for age and stroke volume.

Conclusions: High circulating NK cell count within the first hours after ischemic stroke onset followed by a drop in all lymphocyte subsets identified patients who developed infections and may be caused by a sympathovagal imbalance with sympathetic overweight. These findings need to be validated in larger studies.

No MeSH data available.


Related in: MedlinePlus