The severity of AKI was evaluated according to the RIFLE classification system in which patients were stratified into normal, risk, injury, and failure groups. Broad-spectrum L-165,041 antibiotics were administered within 1 hour of the onset of septic shock, which is the standard of care in the ICUs where the current study was conducted. The antibiotics were adjusted based on clinical responses and drug susceptibility profiles of bacterial cultures. In addition, all patients were given a physiological dose of corticosteroid for refractory hypotension. Comparisons of demographic characteristics were carried out using chi-squared or Fisher��s exact tests for categorical variables and two-tailed independent t-test or Mann-Whitney U test for continuous variables. A multivariate Cox proportional hazards regression model with forward stepwise selection procedures was used to identify the risk factors for 28-day mortality. Binary logistic regression analysis was performed to determine independent variables associated with the development of concomitant AKI. Age, gender, comorbitities, and serum sex hormones levels were included in univariate analysis. A p value of less than 0.1 in the univariate analysis was required for a variable to be entered into the multivariate analysis model. For survival analysis, patients were stratified into subgroups according to serum sex hormone levels. The Kaplan-Meier method was used to estimate survival time and the development of new AKI, and the log-rank test was used to compare mortality between subgroups of patients. Censored analysis was used because observation stopped after a patient was dead or was discharged from the hospital. Receiver operating characteristic curves were constructed to determine the predictive abilities of sex hormone levels for survival and the presence of AKI. A p value of less than 0.05 was considered Thapsigargin statistically significant for all tests. Statistical analysis was performed using a statistical software package. In the present study, we found that serum estradiol and progesterone levels significantly increased in non-survivors of pneumonia-related septic shock patients. In multivariate cox regression model, only serum estradiol level was independent predictors for 28-day mortality. We also demonstrated the additive value of estradiol in combination with APACHE II scores for 28- day mortality prediction.