Abstract
Risk stratification for spontaneous bacterial peritonitis (SBP) in patients with cirrhosis and ascites helps guide care. Existing prediction models, such as end-stage liver disease (MELD) score, are accurate but controversial in clinical practice. We developed and validated a practical user-friendly bedside tool for SBP risk stratification of patients with cirrhosis and ascites. Using classification and regression tree (CART) analysis, a model was developed for prediction of SBP in cirrhosis with ascites. The CART model was derived on data collected from 676 patients admitted from January 2007 to December 2009 retrospectively, and then was prospectively tested in another independent 198 inpatients between January 2010 and December 2010. The accuracy of CART model was evaluated using the area under the receiver operating characteristic curve. The performance of the model was further validated by comparing its predictive accuracy with that of the MELD score. Furthermore, the model was used to stratify SBP among patients with MELD scores under 15. CART analysis identified four variables for prediction of SBP: creatinine, total bilirubin, prothrombin time and white blood cell count, and three risk groups: low (2.0%), intermediate (27.5–33.3%) and high (60.6–86.4%) risk. The accuracy of CART model (0.881) exceeded that of MELD (0.791). Subjects in the intermediate risk and high risk groups had 22.21-fold (95% confident interval (CI), 9.98–49.45) and 173.50-fold (95% CI, 77.68–634.33) increased risk of SBP, respectively, comparing with the low risk group. Similar results were found when this risk stratification was applied to the validation cohort. Cirrhotic patients with ascites at low, intermediate, and high risk for SBP can be easily identified using CART model, which provides clinicians with a validated, practical bedside tool for SBP risk stratification.
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Abbreviations
- A/G:
-
Albumin/globulin ratio
- AKP:
-
Alkaline phosphatase
- ALT:
-
Alanine aminotransferase
- AST:
-
Aspartate aminotransferase
- AUROC:
-
Area under the receiver operating characteristic curve
- CART:
-
Classification and regression tree
- CI:
-
Confident interval
- GGT:
-
γ-Glutamyltransferase
- HBV:
-
Hepatitis B virus
- HE:
-
Hepatic encephalopathy
- INR:
-
International normalized ratio
- MELD:
-
Model of end-stage liver disease
- OR:
-
Odds ratio
- PT:
-
Prothrombin time
- s:
-
Second
- SBP:
-
Spontaneous bacterial peritonitis
- Scr:
-
Serum creatinine
- TB:
-
Total bilirubin
- WBC:
-
White blood cell
References
Altman DG, Vergouwe Y, Royston P, Moons KG (2009) Prognosis and prognostic research: validating a prognostic model. BMJ 338:b605
Andreu M, Sola R, Sitges-Serra A, Alia C, Gallen M, Vila MC, Coll S, Oliver MI (1993) Risk factors for spontaneous bacterial peritonitis in cirrhotic patients with ascites. Gastroenterology 104:1133–1138
Augustin S, Muntaner L, Altamirano JT, Gonzalez A, Saperas E, Dot J, Abu-Suboh M, Armengol JR, Malagelada JR, Esteban R et al (2009) Predicting early mortality after acute variceal hemorrhage based on classification and regression tree analysis. Clin Gastroenterol Hepatol 7:1347–1354
Campillo B, Dupeyron C, Richardet JP, Mangeney N, Leluan G (1998) Epidemiology of severe hospital-acquired infections in patients with liver cirrhosis: effect of long-term administration of norfloxacin. Clin Infect Dis 26:1066–1070
European Association for the Study of the Liver (2010) EASL clinical practice guidelines on the management of ascites, spontaneous bacterial peritonitis, and hepatorenal syndrome in cirrhosis. J Hepatol 53:397–417
Fasolato S, Angeli P, Dallagnese L, Maresio G, Zola E, Mazza E, Salinas F, Dona S, Fagiuoli S, Sticca A et al (2007) Renal failure and bacterial infections in patients with cirrhosis: epidemiology and clinical features. Hepatology 45:223–229
Fernandez J, Navasa M, Gomez J, Colmenero J, Vila J, Arroyo V, Rodes J (2002) Bacterial infections in cirrhosis: epidemiological changes with invasive procedures and norfloxacin prophylaxis. Hepatology 35:140–148
Fernandez J, Navasa M, Planas R, Montoliu S, Monfort D, Soriano G, Vila C, Pardo A, Quintero E, Vargas V et al (2007) Primary prophylaxis of spontaneous bacterial peritonitis delays hepatorenal syndrome and improves survival in cirrhosis. Gastroenterology 133:818–824
Gayatri AA, Suryadharma IG, Purwadi N, Wibawa ID (2007) The relationship between a model of end stage liver disease score (MELD score) and the occurrence of spontaneous bacterial peritonitis in liver cirrhotic patients. Acta Med Indones 39:75–78
Ghassemi S, Garcia-Tsao G (2007) Prevention and treatment of infections in patients with cirrhosis. Best Pract Res Clin Gastroenterol 21:77–93
Guarner C, Sola R, Soriano G, Andreu M, Novella MT, Vila MC, Sabat M, Coll S, Ortiz J, Gomez C, Balanzo J (1999) Risk of a first community-acquired spontaneous bacterial peritonitis in cirrhotics with low ascitic fluid protein levels. Gastroenterology 117:414–419
Khan J, Pikkarainen P, Karvonen AL, Makela T, Peraaho M, Pehkonen E, Collin P (2009) Ascites: aetiology, mortality and the prevalence of spontaneous bacterial peritonitis. Scand J Gastroenterol 44:970–974
Kurosaki M, Sakamoto N, Iwasaki M, Sakamoto M, Suzuki Y, Hiramatsu N, Sugauchi F, Yatsuhashi H, Izumi N (2011) Pretreatment prediction of response to peginterferon plus ribavirin therapy in genotype 1 chronic hepatitis C using data mining analysis. J Gastroenterol 46:401–409
Lee JM, Han KH, Ahn SH (2009) Ascites and spontaneous bacterial peritonitis: an Asian perspective. J Gastroenterol Hepatol 24:1494–1503
Llach J, Rimola A, Navasa M, Gines P, Salmeron JM, Gines A, Arroyo V, Rodes J (1992) Incidence and predictive factors of first episode of spontaneous bacterial peritonitis in cirrhosis with ascites: relevance of ascitic fluid protein concentration. Hepatology 16:724–727
Loomba R, Wesley R, Bain A, Csako G, Pucino F (2009) Role of fluoroquinolones in the primary prophylaxis of spontaneous bacterial peritonitis: meta-analysis. Clin Gastroenterol Hepatol 7:487–493
Malinchoc M, Kamath PS, Gordon FD, Peine CJ, Rank J, ter Borg PC (2000) A model to predict poor survival in patients undergoing transjugular intrahepatic portosystemic shunts. Hepatology 31:864–871
Obstein KL, Campbell MS, Reddy KR, Yang YX (2007) Association between model for end-stage liver disease and spontaneous bacterial peritonitis. Am J Gastroenterol 102:2732–2736
Runyon BA (2009) Management of adult patients with ascites due to cirrhosis: an update. Hepatology 49:2087–2107
Sola E, Gines P (2010) Renal and circulatory dysfunction in cirrhosis: current management and future perspectives. J Hepatol 53:1135–1145
Wu BU, Johannes RS, Sun X, Tabak Y, Conwell DL, Banks PA (2008) The early prediction of mortality in acute pancreatitis: a large population-based study. Gut 57:1698–1703
Acknowledgments
This work was supported by grants from the Scientific Research Foundation of Wenzhou, Zhejiang Province, China (H20090014, Y20090269), Health Bureau of Zhejiang Province (2010KYB070), Research Foundation of Education Bureau of Zhejiang Province (Y201009942) Natural Science Foundation of Shandong Province (ZR2010HQ040), Independent Innovation Foundation of Shandong University (IIFSDU, 2010TS013) and Project of New Century 551 Talent Nurturing in Wenzhou.
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K.-Q. Shi and Y.-C. Fan are co-first author.
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Supplementary Table 1
Subgroup analysis of the patients with the MELD score (DOC 28 kb)
Supplementary Fig. 1
Predictors of SBP and risk stratification for the validation cohort. Terminal subgroups of patients discriminated by the analysis were numbered from one to six. PT prothrombin time, SBP spontaneous bacterial peritonitis, Scr serum creatinine, TB total bilirubine, WBC white blood cell (TIFF 976 kb)
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Shi, KQ., Fan, YC., Ying, L. et al. Risk stratification of spontaneous bacterial peritonitis in cirrhosis with ascites based on classification and regression tree analysis. Mol Biol Rep 39, 6161–6169 (2012). https://doi.org/10.1007/s11033-011-1432-8
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DOI: https://doi.org/10.1007/s11033-011-1432-8