Predictive factors of positive blood culture in sepsis

Background Blood culture is one of methods to determine the microbial etiology of sepsis. but isolatin of organism is difficult because of low level of organism in blood or use of antibiotic .This study was conducted to evaluate predictive factors of positive blood culture in sepsis patients.
Materials & Methods This historical cohort study were done on 320 patients with sepsis during October 2014 to October 2015 who were admitted to the Kashan’s Shahid Beheshti Hospital. By investigation patient's medical records, demographic, clinical and laboratory data such as age, sex, history of hospitalization, temperature, blood pressure, tachycardia, tachypnea, C reactive protein (CRP )serum levels, white blood cell count, erythrocyte sedimentation rate(ESR) and outcomes were extracted. Chi square, Mann-Witney U and t-test were used in data analysis.
Results The mean age of patients in the group with positive cultures (case groups) was 67.93±12.12 years and in patients with negative culture (control group) was 64.67±13.87 years (p=0.03). The frequency of the underlying disease, recent hospitalization, hypotension and tachypnea in the case group was significantly more than control group. Logistic regression analysis showed that CRP serum levels, erythrocyte sedimentation rate and white blood cell counts in patients with sepsis are associated with blood culture results. Data was analyzed using the SPSS version 16 software.
Conclusion In this study difference between two group according to age,sex, nationality, mean temperature, tachycardia,loss of consciousness,and mortality was not significant but there was significant association between underlying disease,history of hospitaliztion,hypotension,tachpnea, CRP,ESR,WBC. And finally concluded that CRP,ESR,WBC was associated with posistve blood culture but this association was not between positive blood culture and mortality.