Objective To explore the diagnostic value of serum C-reactive protein(CRP),serum amyloid A(SAA)and procalcitonin(PCT)combined with lactate dehydrogenase(LDH)and adenosine deaminase(ADA)in cerebrospinal fluid for elderly patients with central nervous system infection and their differential significance for different infection types.Methods A total of 97 elderly patients with central nervous system infection were enrolled as the infection group,including 31 cases with tuberculous meningitis(tuberculous meningitis group),36 cases with suppurative meningitis(suppurative meningitis group)and 30 cases with viral meningitis(viral meningitis group).A total of 97 patients with normal laboratory examination indexes who were treated due to primary headache during the same period were enrolled as the control group.The samples of fasting elbow venous blood were collected in the early morning of the next day after admission,and the serum was isolated to detect CRP and SAA levels.When consultation,lumbar puncture was performed to collect cerebrospinal fluid for the detection of LDH and ADA levels.The differences in above indexes were compared between groups,and diagnostic efficiency of each index and combined detection for central nervous system infection in elderly was analyzed by receiver operating characteristic(ROC)curves.Results The serum levels of CRP,SAA and PCT,and LDH and ADA in cerebrospinal fluid were higher in the infection group than those in the control group(P＜0.05).ROC curve analysis showed that the area under the curve(AUC)values of serum CRP,SAA and PCT,and cerebrospinal fluid LDH and ADA,and combined detection in the diagnosis of central nervous system infection were all>0.70(P＜0.05),showing good predictive efficiency and diagnostic efficiency,and the diagnostic efficacy of combined detection was the best.The cut-off values of serum CRP,SAA and PCT,cerebrospinal fluid LDH and ADA were 6.32 mg/L,33.86 mg/L,2.81 μg/L,33.53 U/L and 1.99 U/L,respectively.The serum levels of CRP,SAA and PCT were the highest in the suppurative meningitis group,while which were the lowest in the viral meningitis group.The cerebrospinal fluid levels of LDH and ADA were the highest in the tuberculous meningitis group,while which were the lowest in the viral meningitis group(P＜0.05).Conclusion The combined detection of serum CRP,SAA and cerebrospinal fluid PCT and LDH has certain diagnostic value for elderly central nervous system infection,which is beneficial to identify infection types.

Objective To explore the diagnostic value of serum C-reactive protein(CRP),serum amyloid A(SAA)and procalcitonin(PCT)combined with lactate dehydrogenase(LDH)and adenosine deaminase(ADA)in cerebrospinal fluid for elderly patients with central nervous system infection and their differential significance for different infection types.Methods A total of 97 elderly patients with central nervous system infection were enrolled as the infection group,including 31 cases with tuberculous meningitis(tuberculous meningitis group),36 cases with suppurative meningitis(suppurative meningitis group)and 30 cases with viral meningitis(viral meningitis group).A total of 97 patients with normal laboratory examination indexes who were treated due to primary headache during the same period were enrolled as the control group.The samples of fasting elbow venous blood were collected in the early morning of the next day after admission,and the serum was isolated to detect CRP and SAA levels.When consultation,lumbar puncture was performed to collect cerebrospinal fluid for the detection of LDH and ADA levels.The differences in above indexes were compared between groups,and diagnostic efficiency of each index and combined detection for central nervous system infection in elderly was analyzed by receiver operating characteristic(ROC)curves.Results The serum levels of CRP,SAA and PCT,and LDH and ADA in cerebrospinal fluid were higher in the infection group than those in the control group(P＜0.05).ROC curve analysis showed that the area under the curve(AUC)values of serum CRP,SAA and PCT,and cerebrospinal fluid LDH and ADA,and combined detection in the diagnosis of central nervous system infection were all>0.70(P＜0.05),showing good predictive efficiency and diagnostic efficiency,and the diagnostic efficacy of combined detection was the best.The cut-off values of serum CRP,SAA and PCT,cerebrospinal fluid LDH and ADA were 6.32 mg/L,33.86 mg/L,2.81 μg/L,33.53 U/L and 1.99 U/L,respectively.The serum levels of CRP,SAA and PCT were the highest in the suppurative meningitis group,while which were the lowest in the viral meningitis group.The cerebrospinal fluid levels of LDH and ADA were the highest in the tuberculous meningitis group,while which were the lowest in the viral meningitis group(P＜0.05).Conclusion The combined detection of serum CRP,SAA and cerebrospinal fluid PCT and LDH has certain diagnostic value for elderly central nervous system infection,which is beneficial to identify infection types.