Development and validation of a five-factor score for prediction of pathologic pneumatosis

BACKGROUND: The significance of pneumatosis intestinalis (PI) remains challenging. While certain clinical scenarios are predictive of transmural ischemia, risk models to assess the presence of pathologic PI are needed. The aim of this study was to determine what patient factors at the time of radiographic diagnosis of PI predict the risk for pathologic PI. METHODS: We conducted a retrospective cohort study examining patients with PI from 2010 to 2016 at a multicenter hospital network. Multivariate logistic regression was used to develop a predictive model for pathologic PI in a derivation cohort. Using regression-coefficient–based methods, the final multivariate model was converted into a five-factor–based score. Calibration and discrimination of the score were then assessed in a validation cohort. RESULTS: Of 305 patients analyzed, 102 (33.4%) had pathologic PI. We identified five factors associated with pathologic PI at the time of radiographic diagnosis: small bowel PI, age 70 years or older, heart rate 110 bpm or greater, lactate of 2 mmol/L or greater, and neutrophil-lymphocyte ratio 10 or greater. Using this model, patients in the validation cohort were assigned risk scores ranging from 0 to 11. Low-risk patients were categorized when scores are 0 to 4; intermediate, score of 5 to 6; high, score of 7 to 8; and very high risk, 9+. In the validation cohort, very high-risk patients (n = 17; 18.1%) had predicted rates of pathologic pneumatosis of 88.9% and an observed rate of 82.4%. In contrast, patients labeled as low risk (n = 37; 39.4%) had expected rates of pathologic pneumatosis of 1.3% and an observed rate of 0%. The model showed excellent discrimination (area under the curve, 0.90) and good calibration (Hosmer-Lemeshow goodness-of-fit, p = 0.37). CONCLUSION: Our score accurately stratifies patient risk of pathologic pneumatosis. This score has the potential to target high-risk individuals for expedient operation and spare low-risk individuals invasive interventions.