Abstract: Objective To construct a Nomogram prediction model for spontaneous bacterial peritonitis (SBP) in liver cirrhosis (LC) based on biological indicators. Methods A total of 185 LC patients admitted to the Affiliated Hospital of Chengde Medical College from March 2023 to March 2024 were selected, and the incidence of SBP during hospitalization was evaluated. According to whether SBP occurs, the patients were divided into a SBP group and a non-SBP group. The general information and biological indicators of the patients at admission were compared between these two groups. Logistic regression analysis was used to identify the influencing factors of SBP in LC patients. Based on these factors, a nomogram prediction model for SBP in LC patients was constructed. The predictive value of the nomogram prediction model was evaluated using receiver operating characteristic (ROC) curves and decision curves (DCA) methods. Results The incidence of SBP during hospitalization in LC patients was 22.70%. At admission, age, proportion of diabetes, abdominal pain, fever, hepatic encephalopathy, hepatorenal syndrome, the proportion of Child-Pugh grade C, peripheral blood white blood cell count, total bilirubin (TBil), C-reactive protein (CRP), procalcitonin (PCT), and CD64 levels in SBP group were (62.1±7.4) years old, 35.71%, 21.43%, 33.33%, 14.29%, 9.52%, 47.62%, (5.08±1.26) 10⁹/L, (81.35±16.27) μmol/L, (9.06±1.82) mg/L, (0.49±0.12) ng/mL, and (11.63±3.85) ng/mL, respectively, which were higher than those of (56.9±6.8) years old, 13.99%, 8.39%, 16.08%, 2.80%, 1.40%, 23.08%, (4.31±1.15) 10⁹/L, (70.76±14.31) μmol/L, (7.43±1.69) mg/L, (0.31±0.10) ng/mL, (7.28±2.31) ng/mL in the non-SBP group. The albumin (Alb) and FIB levels were (30.06±5.41) g/L and (159.37±46.18) mg/L, respectively, which were lower than those of (35.17±6.84) g/L and (210.45±60.72) mg/L in the non-SBP group (P<0.05). At admission, age, diabetes, hepatic encephalopathy, Child-Pugh grade, Alb, TBil, CRP, PCT, CD64, FIB levels in peripheral blood were all the influencing factors of SBP in LC patients (P<0.05); A nomogram prediction model for the occurrence of SBP in LC patients was constructed based on the influencing factors. The AUC of the prediction model was 0.864 (95%CI=0.796~0.932), with a sensitivity of 83.33%, a specificity of 85.31%, and an accuracy of 86.26% for the occurrence of SBP in LC patients. The nomogram prediction model had a significant positive net benefit and good clinical utility in predicting SBP; the external evaluation results showed that the nomogram prediction model had a sensitivity of 84.00%, a specificity of 83.53%, and an accuracy of 83.64% in predicting SBP in LC patients. Conclusion The Nomogram prediction model for SBP in LC patients based on biological indicators has high predictive value and clinical efficacy, and can provide reliable clinical evidence for early identification of high-risk SBP patients in clinical practice.

Key words: Cirrhosis, Spontaneous bacterial peritonitis, Biological indicators, Nomogram, Prediction