To explore the clinical significance of combined detection of serum prothrombin fragment 1+ 2 (F_{1+ 2}), beta-thromboboglobulin (β-TG), thrombomodulin (TM) and D-Dimer (D-D) in the early diagnosis of cerebral infarction.

The case group selected 125 cases from the patients who were diagnosed as cerebral infarction in neurology department of the Gaotang County People's Hospital from January 2015 to June 2017. The patients with cerebral infarction were grouped according to the sizes of head CT or MRI lesions. There were 42 cases in the large infarction group, 40 cases in the middle infarction group and 43 cases in the small infarction group. According to the National Institutes of Health (NIHSS) score on the degree of nerve function defect: there were 26 cases in the severe group, 55 cases in the moderate group and 44 cases in the mild group. Fifty cases of health check-up outpatient were selected as control group. The levels of F_{1+ 2}, β-TG, TM and D-D were measured by double antibody sandwich enzyme-linked immunosorbent assay (ELISA). A single factor variance analysis was used to compare the levels of coagulation molecules among different groups, and the values of each index in the early diagnosis of cerebral infarction were compared under the receiver operating characteristic (ROC) curve (AUC).

The serum levels of F_{1+ 2}, β-TG, TM and D-D were statistically significant in the coutrol group, small infarct group, middle infarct group and large infarct group (F=62.42, 43.26, 56.73, 22.34; P<0.01). The serum levels of F_{1+ 2} [small infarct group (2.67±0.24)nmol/L, middle infarct group (2.84±0.26)nmol/L, large infarct group (3.19±0.30)nmol/L], β-TG[small infarct group (61.83±5.64)μg/L, middle infarct group (73.68±6.47)μg/L, large infarct group (81.32±7.75)μg/L], TM [small infarct group (67.40±5.82)μg/L, middle infarct group (74.84±6.37)μg/L, large infarct group (85.72±7.64)μg/L] and D-D [small infarct group (2 541.10±226.24)μg/L, middle infarct group (2 658.38±232.01)μg/L, large infarct group (2 724.47±256.35)μg/L] in each group were higher than those in control group [(0.27±0.02)nmol/L, (3.74±0.32)μg/L, (5.75±0.45)μg/L, (106.10±81.24)μg/L], the differences were statistically significant [small infarct group (q=18.62, 23.45, 12.76, 28.56; P<0.01), middle infarct group(q=19.59, 25.67, 13.83, 31.21; P<0.01), large infarct group(q=21.24, 26.38, 14.12, 31.97; P<0.01)] .The serum levels of F_{1+ 2} [mild group (2.42±0.21)nmol/L, moderate group (2.77±0.25)nmol/L, severe group (2.98±0.27)nmol/L], β-TG [mild group (62.34±6.02)μg/L, moderate group (78.17±6.94)μg/L, severe group (80.76±7.62)μg/L], TM [mild group (71.93±6.34)μg/L, moderate group (76.72±7.18)μg/L, severe group (88.94±8.62)μg/L], D-D [mild group (2 583.37±237.04)μg/L, moderate group (2 667.46±249.33)μg/L, severe group (2 749.29±260.15)μg/L] were higher than those in the control group [mild group (q=16.58, 21.22, 12.37, 21.64; P<0.01), moderate group (q=18.32, 24.67, 16.44, 25.73; P<0.01), severe group (q=22.47, 32.53, 19.59, 34.65; P<0.01)]. There were no significant differences in the levels of serum F_{1+ 2}, β-TG, TM and D-D in the case groups(P>0.05). The sensitivity and specificity of F_{1+ 2} were 78.51% and 86.73%. The sensitivity and specificity of β-TG were 82.62%, 85.74%. The sensitivity and specificity of TM were 92.84%, 86.22%. The sensitivity and specificity of D-D were 67.46%, 80.81%. The sensitivity and specificity of F_{1+ 2}, β-TG, TM and D-D were 96.32%, 98.63%. The ROC curves of the single item of F_{1+ 2}, β-TG, TM and D-D were 0.854, 0.823, 0.876, 0.781, and the AUC of TM curve was the largest.

The combined determination of serum F_{1+ 2}, β-TG, TM and D-D levels can provide an experimental basis for early diagnosis of cerebral infarction.