Abstract: Objective To explore the differences in diagnostic and treatment characteristics and prognosis in septic shock occurring in different locations in the pediatric intensive care unit (PICU). 
Methods A total of 203 children with septic shock in the PICU of a single center were retrospectively included and divided into the hospital-acquired septic shock group (hospital-acquired group, n=45) and the community-acquired septic shock group (community-acquired group, n=158). The differences in demographics, underlying diseases, infectious foci, treatment and prognosis between the two groups were compared, and the influencing factors for the prognosis of children with septic shock were analyzed. 
Results The hospital-acquired group had older age ［5.6(10.3) years vs. 2.1(6.8) years, and higher proportions of underlying diseases ［(62.2%(28/45) vs. 36.1%(57/158)］, malignant hematological/neoplastic diseases ［44.4%(20/45) vs. 18.9%(30/158)］ and bone marrow suppression after chemotherapy ［31.1%(14/45) vs. 1.8%(3/158)］ than the community-acquired group, showing significant differences (P＜0.05). In the hospital-acquired group, white blood cells ［1.42(10.61)×109/L］ and platelets ［26(133)×109/L］ were lower than those in the community-acquired group ［8.15(13.53)×109/L, 151(188)×109/L］, while C-reactive protein ［138(112) mg/L］ was higher than that in the community-acquired group ［64(95) mg/L］, suggesting significant differences (P＜0.05). In terms of infectious foci, the proportions of the respiratory tract and central nervous system as infectious foci in the hospital-acquired group were lower than those in the community-acquired group ［8.9%(4/45) vs. 29.1%(46/158), 6.7%(3/45) vs. 20.3%(32/158)］, and the proportion of bloodstream infection was higher than that in the community-acquired group ［35.5%(16/45) vs. 11.1%(23/158)］, showing significant differences (P＜0.05). The positive rate of fungi in the hospital-acquired group was higher than that in the community-acquired group ［8.9%(4/45) vs. 1.3%(2/158)］, showing significant differences (P＜0.05). The proportion of the use of two antimicrobial drugs in the community-acquired group was higher than that in the hospital-acquired group, the proportion of the use of three or more antimicrobial drugs in the hospital-acquired group was higher than that in the community-acquired group, and the proportion of anti-fungal drug use in the hospital-acquired group was higher than that in the community-acquired group, showing significant differences (P＜0.05). The proportion of brain dysfunction in the hospital-acquired group was higher than that in the community-acquired group ［17.7%(8/45) vs. 6.3%(10/158)］, the length of hospital stay was longer than that in the community-acquired group ［15(21) d vs. 11(17) d］, and the in-hospital mortality was higher than that in the community-acquired group ［31.1%(14/45) vs. 15.8%(25/158)］, showing significant differences (P＜0.05). Logistic regression analysis showed that hospital-acquired septic shock, combined malignant hematological/neoplastic diseases, pediatric sequential organ failure assessment score, lactic acid, platelets, activated partial thromboplastin time, international normalized ratio, invasive mechanical ventilation, use of vasoactive drugs and continuous blood purification were the influencing factors for the death of hospitalized children with septic shock (OR values=1.04, 2.42, 1.12, 1.20, 1.09, 0.48, 0.55, 0.22, 0.56 and 0.25). 
Conclusion Compared with children with community-acquired septic shock, children with hospital-acquired septic shock have a higher proportion of underlying diseases, a higher demand for anti-infective and vasoactive drugs, and a worse in-hospital prognosis. 

Key words: shock, septic, pathogens, prognosis