To observe the changes of spleen volume in patients with acute cerebral infarction, and to explore the relationship between the spleen volume and platelet reactivity, inflammatory factors′ lymphocyte subsets.

This is a case control study. Thirty patients with acute cerebral infarction from January 2017 to June 2017 in Department of Neurology, Weihai Municipal Hospital were included. The spleen volume, arachidonic acid-induced maximum platelet aggregation ratio (AA-MAR), interferon gamma (IFN-γ) and lymphocyte subsets of patients were monitored in 24 hours of stroke, at 48 hours of stroke, at four days of stroke and at seven days of stroke. Twenty patients without acute cerebral infarction with the same baseline data were selected as the control group, to determine the baseline of spleen volume, AA-MAR, IFN-γ and lymphocyte subsets. A t test was used to describe the changes of spleen volume, AA-MAR, IFN-γ and lymphocyte subsets at different time points, and Pearson′s correlation analysis was used to estimate the relationship between the spleen volume and these variables.

Compared with the control group ((120.12±10.28) cm³), the patients with acute cerebral infarction in 24 hours of stroke ((117.48±7.93) cm³) and at 48 hours of stroke ((111.61±9.21) cm³) had smaller spleen volume (t=-2.142, P<0.05; t=-2.790, P<0.01), whereas at four days ((121.31±8.16) cm³) and seven days of stroke ((126.11±10.31) cm³) had bigger spleen volume (t=2.242, P<0.05; t=2.762, P<0.01), with the spleen volume decreased first and increased later. Compared with the control group, the patients with acute cerebral infarction had more AA-MAR (control group: 20.97%±8.21%; 24 h: 31.86%±9.54%, t=3.165, P<0.01; 48 h: 41.38%±8.55%, t=3.254, P<0.01; 4 d: 35.34%±8.15%, t=3.203, P<0.01; 7 d: 29.38%±10.46%, t=2.494, P<0.05) and IFN-γ(pg/L, control group: 15.21±5.21; 24 h: 29.75±4.57, t=3.262, P<0.01; 48 h: 43.37±12.15, t=3.304, P<0.01; 4 d: 40.44±9.86, t=3.291, P<0.01; 7 d: 20.93±5.51, t=2.417, P<0.05) at different time points, with the most AA-MAR at 48 hours of onset, and the most IFN-γ at four days of stroke. Compared with the control group, the patients with acute cerebral infarction had more T₄, B lymphocytes and natural killer lymphocytes at the four time points, while the level of T₈ lymphocytes did not show statistically significant difference even though also increased at the four time points. The correlation analysis results showed that in patients with acute cerebral infarction, the level of AA-MAR (r=-0.397, P<0.05; r=-0.515, P<0.01; r=-0.382, P<0.05) and IFN-γ (r=-0.408, P<0.05; r=-0.479, P<0.01; r=-0.378, P<0.05) was negatively corelated with the spleen volume in 24 hours of onset, at 48 hours of stroke and at four days of stroke; the level of T₄, B and natural killer lymphocytes were negatively corelated with the spleen volume in 24 hours of stroke and at 48 hours of stroke.

After the acute cerebral infarction onset, the spleen volume tends to reduce and then increases, the levels of platelet reactivity, inflammatory factors and lymphocyte subsets are correlated with the spleen volume, and the spleen may aggravate the brain injury by releasing platelets inflammatory factors and lymphocyte subsets.

Stroke; Spleen; Platelet aggregation; Interferon-gamma; Lymphocytes