Objective:To understand the clinical and pathogenic characteristics of sepsis at different sites of infection and to analyze the impact of different sites of infection,pathogenesis,and sources of infection acquisition on sequential organ dysfunction and prognosis of patients with sepsis.Methods:From January 2020 to June 2022,134 patients with sepsis admitted to the emergency ICU of the First Affiliated Hospital of Nanchang University were retrospectively analysed.The patients were divided into five groups according to the diagnosis of the site of infection by the patients’ sending samples and the receiving physicians: bloodstream infection group,lung infection group,abdominal infection group,urinary tract infection group and other groups,while other groups included central nervous system infection and skin soft tissue infection.The general clinical data and pathogenic findings of the patients were collected and counted,and the differences in general conditions and the distribution of pathogenic bacteria at different sites of infection were counted.Patients’ organ function indices were recorded,including respiratory function index(oxygenation index),coagulation function index(platelets,PT,APTT),liver function index(bilirubin,liver enzymes),cardiovascular function index(blood pressure,vasoactive drugs),renal function index(creatinine,urea nitrogen),central nervous function index(GCS score),and statistical analysis of the effect of different sites of infection,etiology and source of infection acquisition on sequential organ dysfunction.The correlation between SOFA score and WBC,PCT,IL-6,albumin and arterial blood lactate level was analysed.Patients were followed for 28 days and sepsis patients were divided into survival and mortality groups based on survival at 28 days.The relationship between site of infection and mortality was analysed using univariate analysis to find factors affecting sepsis prognosis and Cox regression for factors with p<0.1.Kaplan-Meier curves were used to compare survival between groups with different sites of infection.Results:The most common sites of infection in sepsis are respiratory tract,abdominal cavity,and urinary system.The proportion of females with urinary tract infections is higher than that of males,with statistical significance(P<0.05).In community-acquired infections,blood infections are mainly caused by Staphylococcus aureus,abdominal infections by Escherichia coli and Klebsiella pneumoniae,and urinary tract infections by Escherichia coli.The most common sites of hospital-acquired infections are respiratory and abdominal infections,with Gram-negative bacteria being the main pathogens,of which Acinetobacter baumannii has the highest proportion(49%),followed by Klebsiella pneumoniae(26%).The incidence and score of respiratory dysfunction were highest in pulmonary infections,while liver dysfunction was highest in abdominal infections,with statistical differences when compared with other groups(P<0.05).There was no statistically significant difference in the incidence and score of respiratory and liver dysfunction among other infection sites(P>0.05).The incidence of coagulation dysfunction was lower in pulmonary infections than in blood,abdominal,urinary,and other sites of infection,with statistical significance(P<0.05).The score of coagulation dysfunction was higher in blood infections than in pulmonary infections,with statistical significance(P<0.05).The incidence and score of neurological dysfunction were higher in pulmonary infections than in blood,urinary,and abdominal infections,with statistical significance(P<0.05).The incidence and score of cardiovascular and renal dysfunction showed no statistically significant differences among various infection sites(P>0.05).Sequential organ function impairment was higher in gram-negative than in gram-positive bacteria.Hospital-acquired infections have higher sequential organ function impairment than community-acquired infections.There is a positive correlation between SOFA score and PCT,IL-6,and lactate(P<0.01),while there is a negative correlation between SOFA score and albumin(P<0.01).There was no statistically significant difference in mortality between Grampositive and Gram-negative bacteria in community-acquired infections(P=0.788),but the mortality rate was higher in patients with healthcare-associated infections than in those with community-acquired infections alone(P=0.029).When comparing the 28-day mortality group and the survival group,the former had higher age,IL-6,creatinine,blood urea nitrogen,lactate levels,pulmonary infection incidence,APACHE II score,and SOFA score than the latter(P<0.05).Cox regression analysis showed that pulmonary infection was significantly associated with the highest mortality rate(P<0.05).Kaplan-Meier survival analysis showed that there were differences in survival rates among different infection sites,and the survival rate in pulmonary infections was the lowest,with statistical significance(P<0.05).Conclusion:1.The effect of different sites of infection,pathogenic bacteria and sources of infection acquisition on sequential organ dysfunction in sepsis is variable.2.PCT,IL-6,arterial lactate level and SOFA score are positively correlated,and albumin level and SOFA score are negatively correlated,which may reflect the severity of organ dysfunction in sepsis.3.The prognosis varies by site of infection in sepsis,and pulmonary infections have the worst prognosis and highest mortality. |