Transmural Intestinal Necrosis Research Articles

Irreversible Transmural Intestinal Necrosis in Acute Mesenteric Ischemia: Retrospective Cohort Study from a High-Volume Hospital.

Background: Owing to the low incidence rate and nonspecific symptoms of acute mesenteric ischemia (AMI), the identification and prediction of irreversible transmural intestinal necrosis (ITIN) and extensive bowel resection (≥100 cm) (EBR) are difficult and critical. This study aimed to investigate the risk factors for ITIN and EBR in patients with AMI. Methods: The clinical data of 254 AMI patients were retrospectively analyzed. Furthermore, the incidence of ITIN and EBR were set as dependent variables, and relevant risk factors were screened using univariate and multivariate logistic regression analyses. The comparisons of surgical characteristics and postoperative recovery outcomes between the EBR and control group were also conducted. Results: The presence of hemorrhagic (odds ratio [OR] = 28.356, P < .001) or other types ascites (OR = 13.051, P = .003), peritonitis (OR = 8.463, P = .005), intestinal diameter >2.35 cm (OR = 5.493, P = .020), and serum creatinine (CREA) >95 μmol/L (OR = 4.866, P = .048) were identified as independent risk factors for ITIN in patients with AMI. In addition, serum C-reactive protein (CRP) >15 mg/L (OR = 38.023, P = .006), and CREA >100 μmol/L (OR = 6.248, P = .035) were proved to be independently associated with EBR for ITIN cases. Compared to the control group, EBR significantly increased the likelihood of requiring enterostomy (P = .001), blood transfusion (P = .002), and transfer to intensive care unit (P = .016), while also prolonging the recovery time for intestinal function (P = .014). Conclusions: The presence of ascites, peritonitis, intestinal diameter >2.35 cm, and serum CREA >95 μmol/L were independently correlated with ITIN for AMI cases, while serum CRP >15 mg/L and CREA >100 μmol/L independently increased the risk of EBR.

Factors that may affect the outcome of acute occlusive mesenteric ischemia. A single-center study

BackgroundAcute mesenteric ischemia is a rare but lethal disease. Acute occlusive mesenteric ischemia consists of mesenteric artery embolism, mesenteric artery thrombosis, and mesenteric vein thrombosis. This study aimed to investigate the factors that may affect the outcome of acute occlusive mesenteric ischemia.MethodsData from acute occlusive mesenteric ischemia patients admitted between May 2016 and May 2022 were reviewed retrospectively. Patients were divided into 2 groups according to whether complications(Clavien‒Dindo ≥ 2) occurred within 6 months of the first admission. Demographics, symptoms, signs, laboratory results, computed tomography angiography features, management and outcomes were analyzed.Results59 patients were enrolled in this study. Complications(Clavien‒Dindo ≥ 2) occurred within 6 months of the first admission in 17 patients. Transmural intestinal necrosis, peritonitis, white blood cell count, percentage of neutrophils, percentage of lymphocytes, neutrophil-to-lymphocyte ratio, lactate dehydrogenase, creatine kinase isoenzyme, cardiac troponin I, laparoscopic exploration rate, open embolectomy rate, enterostomy rate, length of necrotic small bowel, length of healthy small bowel, surgical time and intraoperative blood loss differed significantly between groups. Creatine kinase isoenzyme (OR = 1.415, 95% CI: 1.060–1.888) and surgical time (OR = 1.014, 95% CI: 1.001–1.026) were independent risk factors associated with complications(Clavien‒Dindo ≥ 2).ConclusionsOur analysis suggests that acute occlusive mesenteric ischemia patients with a creatine kinase isoenzyme level greater than 2.22 ng/mL or a surgical time longer than 156 min are more likely to experience complications’(Clavien‒Dindo ≥ 2) occurrence within 6 months of the first admission.

Is Intestinal Cell Death in Necrotising Enterocolitis Assorted and Multifarious? A Special Focus on Risk Factors and Their Pathogenic Mechanisms

Necrotising enterocolitis (NEC) is a serious gastrointestinal clinical disorder primarily affecting preterm newborns. It is characterised by a wider histological spectrum, ranging from mild mucosal injury, microvascular thrombosis, and localised necrosis, to transmural intestinal necrosis. In the most severe form, it can be fatal, with complications such as intestinal perforation, peritonitis, and sepsis. Medical management is not clinically efficacious except in mild and self-limiting cases, as it is only focused on symptomatic treatment. Intestinal cell death is regarded as a crucial nascent cellular event in the pathogenesis of NEC that leads to a leaky intestinal barrier, as well as local and systemic inflammation. Therefore, cellular events that besiege intestinal cell death in NEC should be understood in a meticulous and precise manner. This review provides an extensive overview of the different types of cell death in NEC, including apoptosis, necrosis, autophagy, necroptosis, and pyroptosis. This is critically important as it helps us to comprehend the downstream signalling events that play a vital role in the initiation and progression of disease in NEC. Pertinent research studies performed in this regard would unravel novel molecular targets that could form the basis for drafting innovative therapeutic agents for optimising clinical outcomes in NEC.

Is Intestinal Cell Death in Necrotising Enterocolitis Assorted and Multifarious? A Special Focus on Risk Factors and Their Pathogenic Mechanisms

Necrotising enterocolitis (NEC) is a serious gastrointestinal clinical disorder primarily affecting preterm newborns. It is characterised by a wider histological spectrum, ranging from mild mucosal injury, microvascular thrombosis, and localised necrosis, to transmural intestinal necrosis. In the most severe form, it can be fatal, with complications such as intestinal perforation, peritonitis, and sepsis. Medical management is not clinically efficacious except in mild and self-limiting cases, as it is only focused on symptomatic treatment. Intestinal cell death is regarded as a crucial nascent cellular event in the pathogenesis of NEC that leads to a leaky intestinal barrier, as well as local and systemic inflammation. Therefore, cellular events that besiege intestinal cell death in NEC should be understood in a meticulous and precise manner. This review provides an extensive overview of the different types of cell death in NEC, including apoptosis, necrosis, autophagy, necroptosis, and pyroptosis. This is critically important as it helps us to comprehend the downstream signalling events that play a vital role in the initiation and progression of disease in NEC. Pertinent research studies performed in this regard would unravel novel molecular targets that could form the basis for drafting innovative therapeutic agents for optimising clinical outcomes in NEC.

Transmural ischemic bowel necrosis in a patient with Kabuki syndrome: a case report

Kabuki syndrome (KS) is a rare genetic disorder in which mutations in the KMT2D or KDM6A genes result in a wide spectrum of clinical manifestations including development and growth delay; intellectual dysfunction; craniofacial dysmorphism; and various systemic structural and functional defects. We present the case of a 16-year-old male, diagnosed with KS in his infancy. He presented with acute diffuse abdominal pain, accompanied by distension, nausea and clinical data suggestive of intestinal obstruction. After radiological confirmation, focal intestinal necrosis was identified on exploratory surgery, so he underwent intestinal resection and ileostomy in shotgun. The final diagnosis was transmural intestinal ischemic necrosis with acute inflammatory process and serofibrinous peritonitis.

Radiological predictive factors of transmural intestinal necrosis in acute mesenteric ischemia: systematic review and meta-analysis.

Transmural intestinal necrosis (TIN) is related to high mortality in patients with acute mesenteric ischemia (AMI). Radiological predictive factors of TIN in AMI remains controversial. This study aimed to identify the CT-based predictive factors of TIN in AMI. EMBASE and PUBMED were searched for publications predicting TIN using radiological features. Quality Assessment of Diagnostic Accuracy Studies-2 was used to assess the methodological quality of individual studies. Data were presented in terms of diagnostic odds ratio (DOR), sensitivity, specificity, and 95% confidence interval (CI). The random-effects models were used for the meta-analysis. Eleven studies including 1037 cases with AMI were considered. The meta-analysis showed that bowel wall thinning (DOR = 13.10; 95% CI: 3.71, 46.25), decreased or absent bowel wall enhancement (DOR = 5.77; 95% CI: 2.95, 11.30), bowel dilation (DOR = 3.23; 95% CI: 2.03, 5.15), pneumatosis intestinalis (DOR = 5.78; 95% CI: 2.24, 14.95), porto-mesenteric venous gas (DOR = 5.36; 95% CI: 2.14, 13.40), and arterial occlusive AMI (DOR = 2.66; 95% CI: 1.53, 4.63) were risk factors for predicting TIN. Bowel wall thinning and porto-mesenteric venous gas displayed high specificity to diagnose TIN (98%, 95%, respectively). The subgroup analysis showed that decreased or absent bowel wall enhancement (DOR = 8.23; 95% CI: 4.67, 14.51) and bowel dilation (DOR = 3.14; 95% CI: 1.55, 6.39) were predictors of TIN in venous occlusive AMI, which were not related to TIN in arterial-origin AMI. For predicting TIN, there are specific radiological features. The radiological predictors of TIN may differ according to the various causes of AMI. Future primary studies should further evaluate the relationships between radiological signs and TIN based on different etiologies. • Bowel wall thinning, decreased or absent bowel wall enhancement, bowel dilation, pneumatosis intestinalis, porto-mesenteric venous gas, and arterial occlusive AMI were risk factors for predicting TIN. • Decreased or absent bowel wall enhancement and bowel dilation were predictors of TIN in venous occlusive AMI, which were not related to TIN in arterial-origin AMI.

Relationship of superior mesenteric artery thrombus density with transmural intestinal necrosis on multidetector computed tomography in acute mesenteric ischemia.

Acute arterial occlusive mesenteric ischemia with transmural intestinal necrosis (TIN) is a fatal disease, which is difficult to diagnose on multidetector computed tomography (MDCT). The aim of the present study was to determine the relationship of superior mesenteric artery (SMA) thrombus density with TIN on MDCT in patients with acute mesenteric ischemia (AMI) due to SMA thromboembolism. In this retrospective study, 33 patients who underwent abdominal MDCT and angiography for AMI due to SMA thromboembolism were divided into two groups: the AMI with TIN group and the AMI without TIN group. We analyzed the relationships of clinical characteristics, qualitative MDCT signs, and SMA thrombus density with TIN. The SMA thrombus density was measured on non-contrast MDCT. Univariate and multivariate analyses were performed to determine the risk factors for predicting TIN. The diagnostic performances of risk factors were evaluated by receiver-operating characteristic (ROC) curve analysis. Of the patients with AMI enrolled in this study, 33.3% (11/33) were diagnosed with TIN. Peritonitis (P=0.042), bowel wall thinning (P=0.033), and pneumatosis/portomesenteric gas (P=0.010) were significantly associated with TIN. AMI patients with TIN exhibited a higher SMA thrombus density than AMI patients without TIN [41.2±6.1 vs. 34.2±3.0 Hounsfield unit (HU), P=0.003]. Multivariate analysis showed that SMA thrombus density was an independent predictor of TIN [P=0.044, hazard ratio (HR): 1.82, 95% confidence interval (CI): 1.02-3.25]. For diagnosing AMI with TIN, the area under the ROC curve (AUC) of SMA thrombus density (0.83) was larger than those of peritonitis (0.68), bowel wall thinning (0.66), and pneumatosis/portomesenteric gas (0.71). In patients with AMI, erythrocyte-rich thrombus blocking the SMA trunk which has a higher density on MDCT is prone to the occurrence of TIN compared with erythrocyte-scarce thrombus with a lower density. SMA thrombus density could be an independent risk factor for TIN in patients with AMI due to SMA thromboembolism.

Predictors Of Transmural Intestinal Necrosis In Patients Presenting With Acute Mesenteric Ischemia On Computed Tomography.

Introduction: The purpose of the study is to identify the significant imaging predictors of transmural intestinal necrosis in patients with acute mesenteric ischemia (AMI). CT imaging has better performance for the diagnosis of bowel ischemia than clinical and laboratory workup. However, to our knowledge, very few studies have primarily evaluated imaging predictors of bowel necrosis.

Predictors of transmural intestinal necrosis in patients presenting with acute mesenteric ischemia on computed tomography.

The purpose of this study was to identify the significant imaging predictors of transmural intestinal necrosis in patients with acute mesenteric ischemia (AMI). The medical records and CT imaging of 48 patients between 2011 and 2019 suspected of having AMI that underwent exploratory laparotomy with bowel resection and pathological confirmation of ischemic bowel injury were retrospectively reviewed. Using histopathology as a gold standard, various parameters related to vascular insufficiency and bowel injury were analyzed and correlated with outcome of ischemic bowel necrosis using nonparametric tests. Univariate analysis was performed using Fisher's exact test followed by binary logistic regression test for multivariate analysis. 48 Patients (19 females, 40%) with a median age of 68.5 years (IQR of 17 years) built our retrospective cohort. 26 (54%) patients were found to have transmural intestinal necrosis on histopathology (case group) whereas 22 (46%) patients had partial mucosal injury (control group). Pneumatosis intestinalis (p = 0.005, odd's ratio of 2.07-63.14) and severity (> 70% or complete occlusion) of vascular narrowing (p = 0.019, odd's ratio of 1.39-42.30) were identified as the most significant predictors of transmural ischemic necrosis on imaging. Dilatation of bowel did not approach the statistical significance on multivariate analysis although it was found significant on univariate analysis (p = 0.041). Pneumatosis intestinalis and severity of vascular luminal narrowing are the most important imaging predictors of transmural ischemic bowel necrosis in patients presenting with AMI. The presence of these findings on CT scan should raise high index of suspicion for irreversible transmural ischemic necrosis. In the absence of these factors, endovascular management might be beneficial.

Effects of Receptor for Advanced Glycation End-Products (RAGE) Signaling on Intestinal Ischemic Damage in Mice

Objective: Superior mesenteric artery ischemia and nonocclusive mesenteric ischemia are representative diseases of the vascular emergency known as irreversible transmural intestinal necrosis (ITIN). The receptor for advanced glycation end-products (RAGE) belongs to the immunoglobulin superfamily of extracellular ligands, which also includes high-mobility group box 1 (HMGB-1) and proteins of the S100 family. The HMGB-1 ligands have been implicated in the pathogenesis of various inflammatory disorders. This study was designed to investigate the relation between RAGE and ITIN in a murine acute intestinal ischemic model. Materials and Methods: ITIN was induced by clipping the cranial mesenteric artery and the peripheral blood vessels. Mucosal and blood samples were collected and analyzed by reverse-transcription PCR and immunohistochemistry for mucosal inflammation and levels of RAGE-related proteins. The influence of RAGE signaling on intestinal cell reproduction was investigated using the cell scratch test, an in vitro wound-healing assay. Finally, RAGE-related proteins and their respective inhibitors were administered intraperitoneally to ITIN model mice to determine their effects. Results: RAGE-expressing cells were located at the base of the intestinal crypts at day 0. As ITIN progressed, most of the damaged intestinal cells expressed RAGE, and ligands of RAGE such as HMGB-1, S100 A8/A9, and S100β were present in the crypt cells from the bottom to the top. The quantities of S100 A8/A9 and S100β were particularly high, above the levels found in other diseases. When S100 A8/A9 and S100β were applied to small intestinal epithelial cells in vitro, regeneration was significantly impeded. Inflammatory Gr1+ neutrophils and F4/80+ macrophages are involved in tissue ischemia. S100 A8/A9 enhances inflammatory myeloid cell influx. Conclusions: RAGE-related proteins are elevated in ITIN model mice and impede intestinal regeneration in vitro. RAGE-related proteins may be a new therapeutic target or a new marker for ITIN.

Predictive factors of intestinal necrosis in acute mesenteric ischemia

ObjectivesAcute mesenteric ischemia (AMI) is a gastrointestinal and vascular emergency in which the detection of patients requiring intestinal resection is mandatory.MethodsRegistered data of 55 consecutive patients admitted to our center between January 2010 and December 2016 that underwent an explorative laparotomy for a suspected diagnosis of irreversible transmural intestinal necrosis (ITIN) were analyzed. Demographic, clinical, laboratory and CT findings were statistically analyzed in order to search predictive factors of ITIN and their correlation to its clinical spectre.ResultsTobacco use was the most statistically significant (p<0.01) cardiovascular disease risk factor involved in ITIN. Among lab tests, Serum lactate levels ˃ 2mmol/L resulted in a statistically significant association with ITIN (p=0.0001). Organ failure (defined as Marshall score> 2) and the three main CT findings (decreased bowel wall enhancement, bowel loop dilation and demonstrated vessel occlusion) were strongly associated with ITIN (p values: 0.001, 0.007, 0.0013, 0.0005). Only serum lactate levels>2 mmol/L resulted as statistically significant as predictive factors of ITIN in multivariate analysis using logistic regression (OR 49.66 and p-value 0.0021).ConclusionOur univariate and multivariate analysis identified multiple factors (Serum lactate levels ˃ 2mmol/L, Organ failure, CT signs) that could suggest patients that require a surgical approach for ITIN.

Predictors of Acute Transmural Intestinal Necrosis in Acute Mesenteric Ischemia: A Single-center Retrospective Study

Introduction: Acute mesenteric ischemia (AMI) is a rare life-threatening condition, especially for the patients with intestinal transmural necrosis. However, the optimal time of surgical intervention was controversial. As a series study, the current study aimed to identify the predictors for transmural intestinal necrosis (TIN) facilitating the decision making in patients with AMI. Methods: Records of patients with AMI in the period of January 2010 to January 2017 were reviewed in a national gastrointestinal referral center in China. The data of patients including clinical parameters, laboratory examinations and radiologic investigations were analyzed to identify predictors for TIN using binary logistic regression analysis. Results: A total of 158 patients (108 (68.4%) men; median age 59 (50-67) years) were included. The types of AMI were 32.9% in arterial and 67.1% in venous cases. According to the results of pathological assessment and follow-up, sixty-one patients completed conservative treatment successfully, whereas 97 patients required exploratory laparotomy. On laparotomy, superficial ischemic lesions were seen in 8 patients, and intestinal stricture were identified in 27 patients. Overall, 62 were TIN and 96 patients were non-TIN. The 1-year mortality for TIN versus non-TIN was 29% and 2.1%, with an overall mortality of 12.7%. The significant independent predictors for TIN were procalcitonin >0.5ug/L (OR: 3.752(1.619∼8.639); P=0.002), free intraperitoneal fluid (OR: 4.178(1.753∼9.954); P=0.001) and pneumatosis intestinalis (OR: 8.184(3.203∼20.909); P< 0.001) on CT imaging. Area under the receiver operating characteristics curve for the diagnosis of TIN was 0.844 (95% CI: 0.777-0.910) depending on the number of predictive factors. Conclusion: Patients with transmural intestinal necrosis had a significant high mortality rate (above 10-fold) for AMI. We identified the independent predictors for TIN were procalcitonin >0.5ug/L, free intraperitoneal fluid and pneumatosis intestinalis on CT imaging.Close monitoring could help discriminate AMI patients developed transmural intestinal necrosis and in urgent need for bowel resection from those who can be managed with conservative measures. Disclosure: Nothing to disclose

Relative factors of transmural intestinal necrosis in acute superior mesenteric vein thrombosis

Objective: To examine the relative factors of transmural intestinal necrosis (TIN) during multidisciplinary stepwise management facilitating the decision making in patients with acute superior mesenteric vein thrombosis (ASMVT). Methods: Clinical data of patients with ASMVT admitted to Department of General Surgery, Jinling Hospital from January 2009 to June 2017 were reviewed retrospectively. There were 52 males and 37 females, aging (45.9 ± 12.6) years (range: 20 to 69 years). According to the postoperative pathological results and follow-up, the patients were divided into TIN group (n=31) and non-TIN group (n=58, including 18 cases of intestinal stricture). The related factors were compared between ASMVT patients with TIN and patients without TIN by univariate analysis using t test, U test and χ(2) test accordingly, and factors with statistically significance were subsequently submitted to binary Logistic regression analysis. The predictive value and cut-off point of factors were evaluated by receiver operator characteristic (ROC) curve and area under the curve. Results: In univariate analysis, smoking, hypertension, peritonitis, white blood cell count,haemoglobin, international normalized ratio, blood albumin, thrombosis of superior mesenteric branches vein, free intraperitoneal fluid, decrease of bowel wall enhancement and pneumatosis intestinalis were TIN risk factors (all P<0.05). According to the binary Logistic regression analysis, white blood cell count (OR=1.093, 95%CI: 1.010 to 1.182, P=0.027), thrombosis of the superior mesenteric branches vein (OR=11.519, 95%CI: 1.906 to 69.615, P=0.008), pneumatosis intestinalis (OR=11.140, 95%CI: 2.360 to 52.585, P=0.002) were independent relative factors of TIN in patients with AMI, and the area under the ROC curve of the above factors and predictive model was 0.759 (95%CI: 0.647 to 0.871), 0.745 (95%CI: 0.641 to 0.848), 0.737 (95%CI: 0.621 to 0.854), 0.909 (95%CI: 0.847 to 0.971), respectively. The cutoff value of white blood cell count was 18.1 × 10(9)/L. Conclusion: White blood cell levels, superior mesenteric vein branch thrombosis and pneumatosis intestinalis are independent predictors of TIN in ASMVT.

Outcomes and clinical characteristics of transmural intestinal necrosis in acute mesenteric ischemia

Background: Acute mesenteric ischemia (AMI) is a rare life-threatening condition, especially for the patients with transmural intestinal necrosis (TIN). However, the optimal time for surgical intervention is controversial. As a series study, this study aimed to identify the outcomes and clinical characteristic of patients with TIN.Methods: Clinical data of 158 patients with AMI from January 2010 to December 2017 were retrospectively analyzed in a national gastrointestinal referral center in China to confirm the outcomes and identify predictors for TIN.Results: According to the results of pathological assessment and follow-up, 62 patients were TIN and 96 were non-TIN. Patients with TIN have a higher mortality and incidence of severe complications. The significant independent predictors for TIN were arterial lactate level (OR: 4.76 [2.29 ∼ 9.89]), free intraperitoneal fluid (OR: 9.49 [2.56 ∼ 35.24]) and pneumatosis intestinalis (OR: 7.08 [1.68 ∼ 29.82]) in computed tomography (CT) scan imaging. The overall area under the receiver operating characteristics (ROC) curve of the model was 0.934 (95% confidence interval: 0.893 ∼ 0.974). Using ROC curve, the cutoff value of arterial lactate level predicting the onset of TIN was 2.65 mmol/L.Conclusions: Patients concomitant with TIN manifest a higher risk of poor prognosis. The three predictors for TIN were arterial lactate level >2.65 mmol/L, free intraperitoneal fluid and pneumatosis intestinalis. Close monitoring these predictors would help identify AMI patients developed TIN and in urgent need for bowel resection.

3132 Machine Learning for Prediction of Pathologic Pneumatosis Intestinalis Using CT Scans

OBJECTIVES/SPECIFIC AIMS: This retrospective study aims to create and train machine learning models using a radiomic-based feature extraction method for two classification tasks: benign vs. pathologic PI and operation of benefit vs. operation not needed. The long-term goal of our study is to build a computerized model that incorporates both radiomic features and critical non-imaging clinical factors to improve current surgical decision-making when managing PI patients. METHODS/STUDY POPULATION: Searched radiology reports from 2010-2012 via the UPMC MARS Database for reports containing the term “pneumatosis” (subsequently accounting for negations and age restrictions). Our inclusion criteria included: patient age 18 or older, clinical data available at time of CT diagnosis, and PI visualized on manual review of imaging. Cases with intra-abdominal free air were excluded. Collected CT imaging data and an additional 149 clinical data elements per patient for a total of 75 PI cases. Data collection of an additional 225 patients is ongoing. We trained models for two clinically-relevant prediction tasks. The first (referred to as prediction task 1) classifies between benign and pathologic PI. Benign PI is defined as either lack of intraoperative visualization of transmural intestinal necrosis or successful non-operative management until discharge. Pathologic PI is defined as either intraoperative visualization of transmural PI or withdrawal of care and subsequent death during hospitalization. The distribution of data samples for prediction task 1 is 47 benign cases and 38 pathologic cases. The second (referred to as prediction task 2) classifies between whether the patient benefitted from an operation or not. “Operation of benefit” is defined as patients with PI, be it transmural or simply mucosal, who benefited from an operation. “Operation not needed” is defined as patients who were safely discharged without an operation or patients who had an operation, but nothing was found. The distribution of data samples for prediction task 2 is 37 operation not needed cases and 38 operation of benefit cases. An experienced surgical resident from UPMC manually segmented 3D PI ROIs from the CT scans (5 mm Axial cut) for each case. The most concerning ~10-15 cm segment of bowel for necrosis with a 1 cm margin was selected. A total of 7 slices per patient were segmented for consistency. For both prediction task 1 and prediction task 2, we independently completed the following procedure for testing and training: 1.) Extracted radiomic features from the 3D PI ROIs that resulted in 99 total features. 2.) Used LASSO feature selection to determine the subset of the original 99 features that are most significant for performance of the prediction task. 3.) Used leave-one-out cross-validation for testing and training to account for the small dataset size in our preliminary analysis. Implemented and trained several machine learning models (AdaBoost, SVM, and Naive Bayes). 4.) Evaluated the trained models in terms of AUC and Accuracy and determined the ideal model structure based on these performance metrics. RESULTS/ANTICIPATED RESULTS: Prediction Task 1: The top-performing model for this task was an SVM model trained using 19 features. This model had an AUC of 0.79 and an accuracy of 75%. Prediction Task 2: The top-performing model for this task was an SVM model trained using 28 features. This model had an AUC of 0.74 and an accuracy of 64%. DISCUSSION/SIGNIFICANCE OF IMPACT: To the best of our knowledge, this is the first study to use radiomic-based machine learning models for the prediction of tissue ischemia, specifically intestinal ischemia in the setting of PI. In this preliminary study, which serves as a proof of concept, the performance of our models has demonstrated the potential of machine learning based only on radiomic imaging features to have discriminative power for surgical decision-making problems. While many non-imaging-related clinical factors play a role in the gestalt of clinical decision making when PI presents, we have presented radiomic-based models that may augment this decision-making process, especially for more difficult cases when clinical features indicating acute abdomen are absent. It should be noted that prediction task 2, whether or not a patient presenting with PI would benefit from an operation, has lower performance than prediction task 1 and is also a more challenging task for physicians in real clinical environments. While our results are promising and demonstrate potential, we are currently working to increase our dataset to 300 patients to further train and assess our models. References DuBose, Joseph J., et al. “Pneumatosis Intestinalis Predictive Evaluation Study (PIPES): a multicenter epidemiologic study of the Eastern Association for the Surgery of Trauma.” Journal of Trauma and Acute Care Surgery 75.1 (2013): 15-23. Knechtle, Stuart J., Andrew M. Davidoff, and Reed P. Rice. “Pneumatosis intestinalis. Surgical management and clinical outcome.” Annals of Surgery 212.2 (1990): 160.

Oral Antibiotics Reduce Intestinal Necrosis in Acute Mesenteric Ischemia: A Prospective Cohort Study.

To identify treatments likely to prevent progression towards irreversible transmural intestinal necrosis (ITIN) in acute mesenteric ischemia (AMI). Prospective observational cohort study from a French intestinal stroke center. Multivariate analysis using a time-dependent Cox regression model. Between 2009 and 2015, 67 patients with AMI were included. ITIN occurred in 34% of patients and mortality was 13%. Oral antibiotics was independently associated with a decreased risk of ITIN (HR: 0.16 (95% CI = 0.03-0.62); p = 0.01). By decreasing luminal bacterial load and translocation, oral antibiotics in addition to early revascularization might reduce progression of AMI to ITIN.

GW29-e1908 Clinical risk factors for transmural intestinal necrosis in acute mesenteric venous thrombosis

GW29-e1908 Clinical risk factors for transmural intestinal necrosis in acute mesenteric venous thrombosis

Predictive Factors of Intestinal Necrosis in Acute Mesenteric Ischemia: Prospective Study from an Intestinal Stroke Center.

To identify predictive factors for irreversible transmural intestinal necrosis (ITIN) in acute mesenteric ischemia (AMI) and establish a risk score for ITIN. This single-center prospective cohort study was performed between 2009 and 2015 in patients with AMI. The primary outcome was the occurrence of ITIN, confirmed by specimen analysis in patients who underwent surgery. Patients who recovered from AMI with no need for intestinal resection were considered not to have ITIN. Clinical, biological and radiological data were compared in a Cox regression model. A total of 67 patients were included. The origin of AMI was arterial, venous, or non-occlusive in 61%, 37%, 2% of cases, respectively. Intestinal resection and ITIN concerned 42% and 34% of patients, respectively. Factors associated with ITIN in multivariate analysis were: organ failure (hazard ratio (HR): 3.1 (95% confidence interval (CI): 1.1-8.5); P=0.03), serum lactate levels >2 mmol/l (HR: 4.1 (95% CI: 1.4-11.5); P=0.01), and bowel loop dilation on computerized tomography scan (HR: 2.6 (95% CI: 1.2-5.7); P=0.02). ITIN rate increased from 3% to 38%, 89%, and 100% in patients with 0, 1, 2, and 3 factors, respectively. Area under the receiver operating characteristics curve for the diagnosis of ITIN was 0.936 (95% CI: 0.866-0.997) depending on the number of predictive factors. We identified three predictive factors for irreversible intestinal ischemic injury requiring resection in the setting of AMI. Close monitoring of these factors could help avoid unnecessary laparotomy, prevent resection, as well as complications due to unresected necrosis, and possibly lower the overall mortality.

Giant Lambl’s excrescence: a rare incidental finding at autopsy

An 88 year old man collapsed unexpectedly while being transported to a medical examination due to suspected bronchopulmonary infection. Additionally, he had complained of diffuse abdominal pain several hours prior to his death. Resuscitation efforts were unsuccessful and he was pronounced dead at the scene. Due to the unexpected nature of his death, the deceased was referred for postmortem evaluation. His past medical history included chronic obstructive pulmonary disease and ischemic heart disease. Postmortem examination showed unremarkable external findings, except for palpably fractured ribs caused by closed chest compressions performed during attempted resuscitation. Internal examination revealed segmental intestinal infarction secondary to acute occlusion of the superior mesenteric artery by thrombus superimposed upon severe atherosclerosis. Macroscopically, the infarcted section of the intestine appeared gangrenous, edematous, and diffusely dark-purple in color. Sectioning of the heart revealed a small, sea anemone-like structure on the surface of the tricuspid valve measuring 1.2 cm in diameter (Figs. 1, 2). In addition, further autopsy findings included diffuse peritonitis and mild intraperitoneal hemorrhage. Microscopic examination of the aforementioned endocardial structure with hematoxylin-eosin (Fig. 3a, b), Movat’s pentachrome (Fig. 3c), and Masson’s trichrome stains showed fragments of gelatinous, arborescent tissue covered by hyperplastic endothelial cells. All of these structures were composed predominantly of a myxoid stroma with occasional elastic fibers and small amounts of collagen, typical of a papillary fibroelastoma. The cause of death was transmural intestinal necrosis caused by acute arterial thrombotic occlusion sustained as the result of severe mesenteric atherosclerosis.

Necrotizing enterocolitis. Results of surgery

From 1975 to 1991, 132 patients with necrotizing enterocolitis (NEC) were treated at the Department of Pediatric Surgery in Graz. Two of 49 conservatively treated patients died (4%), 1 of these was not operated upon due to complex additional malformations, and the other, a baby with 860 g birth weight (BW), could not be resuscitated sucessfully. Eighty-three patients were treated operatively, 78% with intestinal resection and exteriorization of the bowel. The mean gestational age (GA) was 36 weeks, the mean BW 2,400 g. Nearly all the patients had a medical history of one or more of the well-known predisposing risk factors; 65% had an intestinal perforation at laparotomy, 25% a transmural intestinal necrosis, and 10% pneumatosis or hemorrhagic inflammation of the intestine. Overall mortality in operated patients was 21.7% (n = 18), including 4 deaths in patients with total intestinal necrosis. There were 12 operative deaths, mainly due to progressive septicemia or total intestinal necrosis, and 6 late deaths due to infection, congenital heart disease, or cerebral disease. The mortality declined from 34% before 1985 to 7.7% after 1985 and 6.3% in the last 5 years of this study. Thirty operative complications consisted chiefly of late stenoses, ileus, or late anastomotic complications. Among these patients, only 1 with septicemia after ileostomy closure died. In contrast, all major nonoperative complications caused death, primarily due to infectious problems with septicemia. Mature granulocytes at admission were significantly higher among operated survivors (42.9% vs 23.0%) and represented a valuable predictor of patient survival. In conclusion, despite some differences in this population group with respect to the literature (higher GA and BW), the results show a definite increase in survival, reaching more than 90% of operated patients with NEC.