Gastro-intestinal vascular emergencies

Exploring D-Lactate as a Biomarker for Acute Intestinal Necrosis in 2958 Patients: A Prospective Cross-Sectional Study

BACKGROUND

Timely diagnosis of acute intestinal necrosis (AIN) is lifesaving, but challenging due to unclear clinical presentation. D-lactate has been proposed as an AIN biomarker.

OBJECTIVES

We aimed to test the diagnostic performance in a clinical setting.

METHODS

We performed a cross-sectional prospective study, including all adult patients with acute referral to a single tertiary gastrointestinal surgical department during 2015-2016 and supplemented by enrollment of high-risk in-hospital patients suspected of having AIN during 2016-2019. AIN was verified intraoperatively, and D-lactate was analyzed using an automatic spectrophotometric set-up. A D-lactate cut-off for AIN was estimated using the receiver operating characteristic curve. The performance according to patient subgroups was estimated using the area under the receiver operating characteristic curve (AUC). Given the exploratory nature of this study, a formal power calculation was not feasible.

RESULTS

Forty-four AIN patients and 2914 controls were enrolled. The D-lactate cut-off was found to be 0.0925 mM. Due to lipemic interference, D-lactate could not be quantified in half of the patients, leaving 23 AIN patients and 1456 controls for analysis. The AUC for the diagnosis of AIN by D-lactate was 0.588 (95% confidence interval 0.475-0.712), with a sensitivity of 0.261 and specificity of 0.892. Analysis of high-risk patients showed similar results (AUC 0.579; 95% confidence interval 0.422-0.736).

CONCLUSION

D-lactate showed low sensitivity for AIN in both average-risk and high-risk patients. Moreover, lipemic interference precluded valid spectrophotometric assessment of D-lactate in half of the patients, further disqualifying the clinical utility of D-lactate as a diagnostic marker for AIN.

Therapeutic effect and study of human umbilical cord blood mononuclear cells in patients with ischaemic bowel disease

Ischaemic bowel disease (ICBD) is a group of intestinal ischaemia syndromes caused by various aetiologies of reduced intestinal blood flow or vascular occlusion. ICBD can present as abdominal pain, bloody stool, and diarrhoea. This disease often occurs in middle-aged and elderly individuals with cardiovascular and cerebrovascular diseases. The incidence of ischaemic bowel disease has been increasing for decades, and it is difficult to diagnose, resulting in rapid disease progression and a high mortality rate. Therefore, fully understanding this disease, improving the diagnosis rate of this disease, and finding appropriate treatment methods are urgently needed to improve the condition and prognosis of patients. Umbilical cord blood stem cells are accessible, have weak immunogenicity, and have various biological functions, such as angiogenesis, inflammation and immune regulation. Many studies have confirmed that cord blood stem cells can relieve ischaemia, and these cells have attracted tremendous amounts of attention in regenerative medicine in recent years. In this paper, we discuss the clinical characteristics of ICBD, analyse the characteristics of human umbilical cord blood mononuclear cells (HUCB-MNCs), and use its to treat ischaemic bowel disease. Additionally, we compare the clinical manifestations and related indicators before and after treatment to evaluate the efficacy and safety of these methods.

Correlation between white blood cell count and intestinal resection in patients with acute mesenteric vein thrombosis

OBJECTIVE

Acute mesenteric vein thrombosis (AMVT) is an acute abdominal disease with onset, rapid progression, and extensive intestinal necrosis that requires immediate surgical resection. The purpose of this study was to determine the risk factors for nosocomial intestinal resection in patients with AMVT.

METHODS

We retrospectively analysed 64 patients with AMVT diagnosed by CTA at the Affiliated Hospital of Kunming University of Science and Technology from January 2013 to December 2021. We compared patients who underwent intestinal resection (42 patients) with those who did not undergo intestinal resection (22 patients). The area under the ROC curve was evaluated, and a forest map was drawn.

RESULTS

Among the 64 patients, 6 (9.38%) had a fever, 60 (93.75%) had abdominal pain, 9 (14.06%) had a history of diabetes, 8 (12.5%) had a history of deep vein thrombosis (DVT), and 25 (39.06%) had ascites suggested by B ultrasound or CT after admission. The mean age of all patients was 49.86 ± 16.25 years. The mean age of the patients in the enterectomy group was 47.71 ± 16.20 years. The mean age of the patients in the conservative treatment group (without enterectomy) was 53.95 ± 15.90 years. In the univariate analysis, there were statistically significant differences in leukocyte count (P = 0.003), neutrophil count (P = 0.001), AST (P = 0.048), total bilirubin (P = 0.047), fibrinogen (P = 0.022) and DD2 (P = 0.024) between the two groups. The multivariate logistic regression analysis showed that admission white blood cell count (OR = 1.153, 95% CI: 1.039-1.280, P = 0.007) was an independent risk factor for intestinal resection in patients with AMVT. The ROC curve showed that the white blood cell count (AUC = 0.759 95% CI: 0.620-0.897; P = 0.001; optimal threshold: 7.815; sensitivity: 0.881; specificity: 0.636) had good predictive value for emergency enterectomy for AMVT.

CONCLUSIONS

Among patients with AMVT, patients with a higher white blood cell count at admission were more likely to have intestinal necrosis and require emergency enterectomy. This study is helpful for clinicians to accurately determine whether emergency intestinal resection is needed in patients with AMVT after admission, prevent further intestinal necrosis, and improve the prognosis of patients.

Acute mesenteric ischemia: A case report

Acute mesenteric ischemia is a rare life-threatening diagnostic and therapeutic emergency. Lack of clinical and biological specificity makes the diagnosis difficult. Imaging, particularly computed tomography can help confirm the diagnosis. An underlying cause is identified in about 30%-70% of cases and should always be sought. We report a case of a 51-year-old man with chronic alcoholic liver disease admitted to the emergency department for abdominal pain. Computed tomography showed mesenteric venous thrombosis with signs of small bowel ischemia and cirrhosis with portal hypertension. Through this observation, we describe the imaging aspects of mesenteric ischemia and emphasize the necessity of seeking underlying pathological condition.

Could CT finding of gas in the sole mesenteric artery be a sign of a severe acute ischemia? Presentation of a rare fatal case and a literature review

Contrast-enhanced abdominal CT is the gold standard for the diagnosis of acute mesenteric ischemia (AMI). CT findings include several anomalies like bowel wall thickening, thinning, attenuation, decreased enhancement, dilated fluid-filled loops, pneumatosis, and portal venous gas. A rare case of gas found only in the superior mesenteric artery (SMA) is presented. A contrast-enhanced CT scan was performed in emergency on an 80-year-old man with vague and diffuse abdominal pain, which showed findings of occlusive AMI. Gas was found in the context of the SMA and its branches, but not in the mesenteric and portal veins. The patient underwent emergency surgery but he died the next day in the intensive care unit for complications. The rare CT finding of gas in SMA during an AMI should be considered a radiological sign of irreversible intestinal damage: surgical prompt intervention is needed, even if the mortality rate is high.

Management of acute mesenteric ischaemia: Results of a worldwide survey

BACKGROUND

Acute mesenteric ischaemia (AMI) is a condition with high mortality. This survey assesses current attitudes and practices to manage AMI worldwide.

METHODS

A questionnaire survey about the practices of diagnosing and managing AMI, endorsed by several specialist societies, was sent to different medical specialists and hospitals worldwide. Data from individual health care professionals and from medical teams were collected.

RESULTS

We collected 493 individual forms from 71 countries and 94 team forms from 34 countries. Almost half of respondents were surgeons, and most of the responding teams (70%) were led by surgeons. Most of the respondents indicated that diagnosis of AMI is often delayed but rarely missed. Emergency revascularisation is often considered for patients with AMI but rarely in cases of transmural ischaemia (intestinal infarction). Responses from team hospitals with a dedicated special unit (14 team forms) indicated more aggressive revascularisation. Abdominopelvic CT-scan with intravenous contrast was suggested as the most useful diagnostic test, indicated by approximately 90% of respondents. Medical history and risk factors were thought to be more important in diagnosis of AMI without transmural ischaemia, whereas for intestinal infarction, plasma lactate concentrations and surgical exploration were considered more useful. In elderly patients, a palliative approach is often chosen over extensive bowel resection. There was a large variability in anticoagulant treatment, as well as in timing of surgery to restore bowel continuity.

CONCLUSIONS

Delayed diagnosis of AMI is common despite wide availability of an adequate imaging modality, i.e. CT-scan. Large variability in treatment approaches exists, indicating the need for updated guidelines. Increased awareness and knowledge of AMI may improve current practice until more robust evidence becomes available. Adherence to the existing guidelines may help in improving differences in treatment and outcomes.

High risk and low prevalence diseases: Mesenteric ischemia

INTRODUCTION

Mesenteric ischemia is a rare, frequently misdiagnosed, serious condition that carries with it a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of mesenteric ischemia, including presentation, diagnosis, and management in the emergency department (ED) based on current evidence.

DISCUSSION

Mesenteric ischemia is an abdominal vascular emergency that includes superior mesenteric arterial embolism, arterial thrombosis, venous mesenteric ischemia, and non-occlusive mesenteric ischemia. It is associated with a variety of risk factors including older age, cardiovascular disease, hypercoagulable state, and end-stage renal disease. The presentation depends on the underlying pathophysiology. While arterial embolic disease may present with sudden, severe pain, the early stages of the disease and other forms can present with vague symptoms, including generalized abdominal pain, weight loss, vomiting, and diarrhea. Laboratory testing can suggest the disease with leukocytosis and elevated lactate, but normal values should not be used to exclude the diagnosis. The imaging modality of choice is triple phase computed tomography with non-contrast, arterial, and delayed phases. The initial ED management includes fluid resuscitation, symptomatic therapy, broad-spectrum antibiotics, and anticoagulation. Emergent consultation with a multidisciplinary team including diagnostic and interventional radiologists and cardiovascular and general surgeons is necessary for definitive treatment.

CONCLUSIONS

An understanding of mesenteric ischemia can assist emergency clinicians in diagnosing and managing this disease.

Adenosine A1 receptor agonism protection mechanism in intestinal ischemia/reperfusion injury via activation of PI3K/Akt signaling

Intestinal ischemia/reperfusion (I/R) injury is a common clinical problem with a high mortality rate, resulting from loss of blood flow to an intestinal segment. Adenosine serves a protective role in intestinal I/R injury; however, its potential mechanism is not completely understood. The present study aimed to investigate the protective effects of adenosine A₁ receptor (A₁R) agonists CPA and LUF6941 and whether their mechanisms are associated with the PI3K/Akt signaling pathway. To simulate intestinal I/R injury, a cell oxygen-glucose deprivation/reoxygenation (OGD/R) model was established and the human colon cancer cell line (Caco-2) was incubated with A₁R agonists before OGD/R treatment. The viability of Caco-2 cells was detected by PI and Cell Counting Kit-8 assay, apoptosis was detected using flow cytometry and western blotting was used to analyze protein expression levels of PI3K, Akt and p53 in Caco-2 cells. A₁R agonist pretreatment protected Caco-2 cells against OGD/R-induced cell damage and activated PI3K/Akt signaling. Additionally, apoptosis was inhibited by downregulating phosphorylation of p53 protein, as evidenced by increased cell viability. These findings suggested that A₁R agonists decreased OGD/R damage in Caco-2 cells, which may be due to their anti-apoptotic effects and activation of the PI3K/Akt/p53 signal pathway.

Acute mesenteric ischemia: updated guidelines of the World Society of Emergency Surgery

Acute mesenteric ischemia (AMI) is a group of diseases characterized by an interruption of the blood supply to varying portions of the intestine, leading to ischemia and secondary inflammatory changes. If untreated, this process may progress to life-threatening intestinal necrosis. The incidence is low, estimated at 0.09-0.2% of all acute surgical admissions, but increases with age. Although the entity is an uncommon cause of abdominal pain, diligence is required because if untreated, mortality remains in the range of 50%. Early diagnosis and timely surgical intervention are the cornerstones of modern treatment to reduce the high mortality associated with this entity. The advent of endovascular approaches in parallel with modern imaging techniques is evolving and provides new treatment options. Lastly, a focused multidisciplinary approach based on early diagnosis and individualized treatment is essential. Thus, we believe that updated guidelines from World Society of Emergency Surgery are warranted, in order to provide the most recent and practical recommendations for diagnosis and treatment of AMI.

Effects of Lycopene Attenuating Injuries in Ischemia and Reperfusion

Tissue and organ ischemia can lead to cell trauma, tissue necrosis, irreversible damage, and death. While intended to reverse ischemia, reperfusion can further aggravate an ischemic injury (ischemia-reperfusion injury, I/R injury) through a range of pathologic processes. An I/R injury to one organ can also harm other organs, leading to systemic multiorgan failure. A type of carotenoid, lycopene, has been shown to treat and prevent many diseases (e.g., rheumatoid arthritis, cancer, diabetes, osteoporosis, male infertility, neurodegenerative diseases, and cardiovascular disease), making it a hot research topic in health care. Some recent researches have suggested that lycopene can evidently ameliorate ischemic and I/R injuries to many organs, but few clinical studies are available. Therefore, it is essential to review the effects of lycopene on ischemic and I/R injuries to different organs, which may help further research into its potential clinical applications.

Mesenteric Ischemia and Its Need for Timely Recognition and Management

Mesenteric ischemia is a fatal vascular emergency of the small intestine which, if not diagnosed and treated in time, has a very high mortality rate. Presenting with nonspecific symptoms such as abdominal pain, nausea, constipation, tachycardia, and gastrointestinal bleeds, it can masquerade as other causes of acute abdomen, particularly bowel obstruction. Ideal laboratory tests and markers are still lacking due to complexity in bowel's anatomy, physiology, blood supply, and drainage. We report 10 cases of mesenteric ischemia presented in our center with their demography, laboratory findings, approach to diagnosis, and treatment along with their outcomes at discharge. Out of the ten cases, six cases presented with signs and symptoms of acute bowel obstruction without passage of stool and one with passage of black stool. These seven patients underwent laparotomy, while the remaining three cases who either presented with milder symptoms or refused surgical interventions were managed conservatively. All patients were diagnosed with either acute or chronic mesenteric ischemia based on their operative and/or radiographic findings.

Role of the antioxidant pathway in the healing of peptic ulcers induced by ischemia-reperfusion in male and female rats treated with Eugenia punicifolia

Ischaemia and reperfusion (I/R)-induced gastrointestinal disorders are caused by free radicals, resulting in organ damage and functional disarrangement. This study aimed to investigate the healing effects of hydroalcoholic extracts from the leaves of Eugenia punicifolia (Kunth) DC. (HEEP) in male and female Wistar rats with I/R-induced peptic injuries, and the role of antioxidants in improving this response. After I/R-induced gastric and duodenal injuries, male and female [intact (INT) and ovariectomized (OVZ)] rats were orally treated with HEEP for 6 days. Biochemical analysis was used to determine the catalase (CAT), superoxide dismutase (SOD), and myeloperoxidase (MPO) activities, as well as malondialdehyde and reduced glutathione levels, to measure the gastric and duodenal healing process. Six days of HEEP treatment significantly decreased the I/R-induced gastric [male (73.68%), INT (52.83%), and OVZ (43.13%)] and duodenal damage [male (57.03%), INT (56.04%), and OVZ (54.83%)] in all groups. In OVZ rats, the healing effect of HEEP occurred because of the increased activity of SOD (2x) and CAT (1.16x) in the gastric mucosa. In the duodenal mucosa of INT rats, the extract reduced MPO (20.83%) activity. The 6-day HEEP treatment improved the healing of I/R-induced peptic ulcer injury, with the system acting differently in males and females. The antioxidant system is an important component of the HEEP activity during post-I/R mucosal recovery. This result revealed the importance of antioxidant compounds in minimizing the severity of I/R-related events.

Colonoscopy-related colonic ischemia

Colonoscopy is a risk factor for colon ischemia. The colon is susceptible to ischemia due to its minor blood flow compared to other abdominal organs; the etiology of colon ischemia after colonoscopy is multifactorial. The causative mechanisms include splanchnic circulation impairment, bowel preparation, drugs used for sedation, bowel wall ischemia due to insufflation/barotrauma, and introduction of the endoscope. Gastroenterologists must be aware of this condition and its risk factors for risk minimization, early diagnosis, and proper treatment.

Severe acute ischemic colitis: What is the place of endoscopy in the management strategy?

Background and study aims  Ischemic colitis (IC) is potentially lethal. Clinical and biology information and results of computed tomography (CT) scan and/or colonoscopy are used to assess its severity. However, decision-making about therapy remains a challenge. Patients and methods  This was a retrospective, single-center study between 2006 and 2015. Patients with severe IC who underwent endoscopic evaluation were included. The aims were to determine outcomes depending on endoscopic findings and assess the role of endoscopy in the management. Results  A total of 71 patients were included (men = 48 (68%), mean age = 71 ± 13 years). There was hemodynamic instability in 29 patients (41 %) and severity signs on CT scan in 18 (38 %). Twenty-nine patients (41 %) underwent surgery and 24 (34 %) died. The endoscopic grades were: 15 grade 1 (21 %), 32 grade 2 (45 %), and 24 grade 3 (34%). Regarding patients with grade 3 IC, 55 % had hemodynamic instability, 58 % had severity signs on CT scan, 68 % underwent surgery, and 55 % died. The decision to perform surgery was based on hemodynamic status in 62 % of cases, CT scan data in 14 %, endoscopic findings in 10 %, and other in 14 %. Colectomy was more frequent in patients with grade 3 IC ( P  < 0.05). A mismatch between mucosal aspect (necrosis) and serous (normal) was observed in 13 patients (46 %). Risk factors for colectomy in univariate analysis were aortic aneurysm surgery, hemodynamic instability, no colic enhancement on CT scan, and endoscopic grade 3. Risk factors for mortality in multivariate analysis were hemodynamic instability, colectomy, and Charlson score > 5 ( P  < 0.05). Conclusions  This study suggests a low impact of endoscopy on surgical decision making. Hemodynamic instability was the first indication for colectomy. A discrepancy between endoscopic mucosal (necrosis) and surgical serous (normal) aspects was frequently noted.

Potentially Functional microRNA-mRNA Regulatory Networks in Intestinal Ischemia-Reperfusion Injury: A Bioinformatics Analysis

Background

Intestinal ischemia-reperfusion (II/R) injury is a common clinical complication associated with high mortality, for which microRNA (miRNA) drives potentially its pathophysiological progression. MiRNAs regulate different messenger RNAs (mRNAs). However, the regulatory network between miRNAs and mRNAs in intestinal ischemia-reperfusion injury is elusive.

Methods

We analyzed the different expression of mRNAs and miRNAs in intestinal tissues from patients from three groups (arterial group (group A), venous group (group V), control group (group C)). Common differentially expressed (Co-DE) miRNAs and differentially expressed mRNAs were acquired via concerned analyses among the three groups. Co-DE mRNAs were shared parts of target mRNAs and differentially expression mRNAs. Cytoscape was employed to construct the regulatory network between miRNAs and mRNAs. Gene Ontology (GO) analysis and the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway depicted the functions and potential pathway associated with Co-DE mRNAs. Using the STRING and Cytoscape, we found critical mRNAs in the protein–protein interaction (PPI) network.

Results

The miRNA-mRNA network comprised 8 Co-DE miRNAs and 140 Co-DE mRNAs. Of note, 140 Co-DE mRNAs were targets of these 8 miRNAs, and their roles were established through the functional exploration via GO analysis and KEGG analysis. PPI network and Cytoscape revealed COL1A2, THY1, IL10, MMP2, SERPINH1, COL3A1, COL14A1, and P4HA1 as the top 8 key mRNAs.

Conclusion

This study has demonstrated a miRNA-mRNA regulatory network in intestinal ischemia-reperfusion injury, and explored the key mRNAs and their potential functions. These findings could provide new insight into prognostic markers and therapeutic targets for patients with intestinal ischemia-reperfusion injury in clinical practice.

Accuracy of citrulline, I-FABP and D-lactate in the diagnosis of acute mesenteric ischemia

Early diagnosis of acute mesenteric ischemia (AMI) remains a clinical challenge, and no biomarker has been consistently validated. We aimed to assess the accuracy of three promising circulating biomarkers for diagnosing AMI-citrulline, intestinal fatty acid-binding protein (I-FABP), and D-lactate. A cross-sectional diagnostic study enrolled AMI patients admitted to the intestinal stroke center and controls with acute abdominal pain of another origin. We included 129 patients-50 AMI and 79 controls. Plasma citrulline concentrations were significantly lower in AMI patients compared to the controls [15.3 μmol/L (12.0-26.0) vs. 23.3 μmol/L (18.3-29.8), p = 0.001]. However, the area under the receiver operating curves (AUROC) for the diagnosis of AMI by Citrulline was low: 0.68 (95% confidence interval = 0.58-0.78). No statistical difference was found in plasma I-FABP and plasma D-lactate concentrations between the AMI and control groups, with an AUROC of 0.44, and 0.40, respectively. In this large cross-sectional study, citrulline, I-FABP, and D-lactate failed to differentiate patients with AMI from patients with acute abdominal pain of another origin. Further research should focus on the discovery of new biomarkers.

Dual Pathology: A Rare Association in Surgical Acute Abdomen

Among the causes of acute surgical abdomen intestinal perforation and mesenteric ischemia are some of the leading causes of morbidity and mortality. Gastric perforation has a mortality rate of 20-30% and mesenteric ischemia has a mortality of 60%. The presence of both pathologies in the same patient at the same time is a rare association and very few cases have been reported till now. This association has been described in cases of polyarteritis nodosa. Here we are presenting our case in which no such vascular pathology was identified. We have tried to hypothesize the reason behind this rare association.

A rapid preliminary prediction model for intestinal necrosis in acute mesenteric ischemia: a retrospective study

BACKGROUND

Acute mesenteric ischemia (AMI) is a life-threatening condition. However, there is no accurate method to predict intestinal necrosis in AMI patients that may facilitate early surgical intervention. This study thus aimed to explore a simple and accurate model to predict intestinal necrosis in patients with AMI.

METHODS

A single-center retrospective study was performed on the data of 132 AMI patients treated between October 2011 and June 2020. The patients were divided into the intestinal necrosis and non-intestinal necrosis groups. The clinical characteristics and laboratory data were analyzed by univariate analysis, and the variables with statistical significance were further analyzed by multivariate logistic regression analysis. The independent predictors of intestinal necrosis were determined and a logistic prediction model was established. Finally, the accuracy, sensitivity, and specificity of the model in predicting intestinal necrosis were evaluated.

RESULTS

Univariate analysis showed that white blood cell (WBC) count, blood urea nitrogen (BUN) level, neutrophil ratio, prothrombin time (PT), and LnD-dimer were associated with intestinal necrosis. According to logistic regression multivariate analysis, WBC count, BUN level and LnD-dimer were independent predictors of intestinal necrosis. These parameters were used to establish a clinical prediction model of intestinal necrosis (CPMIN) as follows: model score = 0.349 × BUN (mmol/L) + 0.109 × WBC × 109 (109/L) + 0.394 × LnD - Dimer (ug/L) - 7.883. The area under the receiver operating characteristics (ROC) curve of the model was 0.889 (95% confidence interval: 0.833-0.944). Model scores greater than - 0.1992 predicted the onset of intestinal necrosis. The accuracy, specificity, and sensitivity of the model were 82.6%, 78.2%, and 88.3%, respectively. The proportion of intestinal necrosis in the high-risk patient group (CPMIN score ≥ - 0.1992) was much greater than that in the low-risk patient group (CPMIN score < - 0.1992; 82.7% vs. 15.0%, p < 0.001).

CONCLUSION

The CPMIN can effectively predict intestinal necrosis and guide early surgical intervention to improve patient prognosis. Patients with AMI who are classified as high-risk should be promptly treated with surgery to avoid the potential complications caused by delayed operation. Patients classified as low-risk group can receive non-surgical treatment. This model may help to lower the morbidity and mortality from AMI. However, this model's accuracy should be validated by larger sample size studies in the future.

A clinical approach to acute mesenteric ischemia

PURPOSE OF REVIEW

To summarize current evidence on acute mesenteric ischemia (AMI) in critically ill patients, addressing pathophysiology, definition, diagnosis and management.

RECENT FINDINGS

A few recent studies showed that a multidiscipliary approach in specialized centers can improve the outcome of AMI. Such approach incorporates current knowledge in pathophysiology, early diagnosis with triphasic computed tomography (CT)-angiography, immediate endovascular or surgical restoration of mesenteric perfusion, and damage control surgery if transmural bowel infarction is present. No specific biomarkers are available to detect early mucosal injury in clinical setting. Nonocclusive mesenteric ischemia presents particular challenges, as the diagnosis based on CT-findings as well as vascular management is more difficult; some recent evidence suggests a possible role of potentially treatable stenosis of superior mesenteric artery and beneficial effect of vasodilator therapy (intravenous or local intra-arterial). Medical management of AMI is supportive, including aiming of euvolemia and balanced systemic oxygen demand/delivery. Enteral nutrition should be withheld during ongoing ischemia-reperfusion injury and be started at low rate after revascularization of the (remaining) bowel is convincingly achieved.

SUMMARY

Clinical suspicion leading to tri-phasic CT-angiography is a mainstay for diagnosis. Diagnosis of nonocclusive mesenteric ischemia and early intestinal injury remains challenging. Multidisciplinary team effort may improve the outcome of AMI.

NLRX1/FUNDC1/NIPSNAP1-2 axis regulates mitophagy and alleviates intestinal ischaemia/reperfusion injury

OBJECTIVES

Mitophagy is considered to be a key mechanism in the pathogenesis of intestinal ischaemic reperfusion (IR) injury. NOD-like receptor X1 (NLRX1) is located in the mitochondria and is highly expressed in the intestine, and is known to modulate ROS production, mitochondrial damage, autophagy and apoptosis. However, the function of NLRX1 in intestinal IR injury is unclear.

MATERIALS AND METHODS

NLRX1 in rats with IR injury or in IEC-6 cells with hypoxia reoxygenation (HR) injury were measured by Western blotting, real-time PCR and immunohistochemistry. The function of NLRX1-FUNDC1-NIPSNAP1/NIPSNAP2 axis in mitochondrial homeostasis and cell apoptosis were assessed in vitro.

RESULTS

NLRX1 is significantly downregulated following intestinal IR injury. In vivo studies showed that rats overexpressing NLRX1 exhibited resistance against intestinal IR injury and mitochondrial dysfunction. These beneficial effects of NLRX1 overexpression were dependent on mitophagy activation. Functional studies showed that HR injury reduced NLRX1 expression, which promoted phosphorylation of FUN14 domain-containing 1 (FUNDC1). Based on immunoprecipitation studies, it was evident that phosphorylated FUNDC1 could not interact with the mitophagy signalling proteins NIPSNAP1 and NIPSNAP2 on the outer membrane of damaged mitochondria, which failed to launch the mitophagy process, resulting in the accumulation of damaged mitochondria and epithelial apoptosis.

CONCLUSIONS

NLRX1 regulates mitophagy via FUNDC1-NIPSNAP1/NIPSNAP2 signalling pathway. Thus, this study provides a potential target for the development of a therapeutic strategy for intestinal IR injury.

Etiology and Management of Pediatric Intestinal Failure: Focus on the Non-Digestive Causes

Background: Intestinal failure (IF) is defined as reduction in functioning gut mass below the minimal amount necessary for adequate digestion and absorption. In most cases, IF results from intrinsic diseases of the gastrointestinal tract (digestive IF) (DIF); few cases arise from digestive vascular components, gut annexed (liver and pancreas) and extra-digestive organs or from systemic diseases (non-digestive IF) (NDIF). The present review revised etiology and treatments of DIF and NDIF, with special focus on the pathophysiological mechanisms, whereby NDIF develops. Methods: We performed a comprehensive search of published literature from January 2010 to the present by selecting the following search strings: “intestinal failure” OR “home parenteral nutrition” OR “short bowel syndrome” OR “chronic pseudo-obstruction” OR “chronic intestinal pseudo-obstruction” OR “autoimmune enteropathy” OR “long-term parenteral nutrition”. Results: We collected overall 1656 patients with well-documented etiology of IF: 1419 with DIF (86%) and 237 with NDIF (14%), 55% males and 45% females. Among DIF cases, 66% had SBS and among NDIF cases 90% had malabsorption/maldigestion. Conclusions: The improved availability of diagnostic and therapeutic tools has increased prevalence and life expectancy of rare and severe diseases responsible for IF. The present review greatly expands the spectrum of knowledge on the pathophysiological mechanisms through which the diseases not strictly affecting the intestine can cause IF. In view of the rarity of the majority of pediatric IF diseases, the development of IF Registries is strongly required; in fact, through information flow within the network, the Registries could improve IF knowledge and management.

Predictors and risk factors for intestinal necrosis in patients with mesenteric ischemia

Background

Mesenteric ischemia results in blood flow that is insufficient to meet metabolic demands and subsequent dysfunction of visceral organs, including arterial obstruction and venous thrombosis. Sustained mesenteric ischemia exhausts the ability of capillaries to provide oxygen and initiate an inflammatory reaction, and eventually leads to intestinal mucosal necrosis, a serious and potentially life-threatening condition. Therefore, it is essential that the predictors and risk factors for intestinal necrosis in patients with mesenteric thrombus are explored.

Methods

This study retrospectively enrolled 41 patients with mesenteric ischemia (including mesenteric vein embolism, mesenteric artery thrombosis, and portal vein thrombosis) who were admitted to the Department of Gastrointestinal Surgery, Beijing Tsinghua Changgung Hospital between May 2016 and October 2019; of the patients, 18 were further diagnosed with intestinal necrosis. Comparisons of symptoms, computed tomography angiography (CTA) features, and laboratory examination results were performed between mesenteric ischemia patients with and without intestinal necrosis.

Results

White blood cell count showed an excellent predictive ability for intestinal necrosis in patients with mesenteric ischemia, with an area under the receiver operating characteristic (ROC) curve of 0.772 (P=0.009). The four CTA features [pneumatosis (P=0.016), intestinal swelling (P=0.006), ascitic fluid (P<0.001), and decreased intestinal wall enhancement (P=0.004)] differed significantly between patients with and without intestinal necrosis. Peritonitis showed a strong association with intestinal necrosis (P=0.006) in the univariate analysis, and multivariate analysis further showed their association [odds ratio (OR): 8.53; 95%CI: 1.46-49.81; P=0.017].

Conclusions

White blood cell count is a potential predictor of intestinal necrosis. Peritonitis is a possible risk factor for intestinal necrosis in patients with mesenteric ischemia. A multi-center prospective study with a larger sample size needs to be performed to further investigate these findings.

Bowel ischemia and gangrene-primary true enterolith

Enterolithiasis, or presence of stone concretions in the gastrointestinal tract, is an important but relatively uncommon clinical condition that has recently gained significant attention with advances in the gastrointestinal field. Here, we present a case of an old male having features of bowel Ischemia and gangrene formation. Patient underwent exploratory laparotomy and there was a presence of inflamed Gut with a perforation just one and half feet away from IC junction and an obstruction was also identified by following the dilated bowel loops distally, palpation revealed a hard stone and enterotomy incision at the site delivered a stone. Following it, resection of thickened mesentery was done and loop ileostomy was made. The most important prognostic factor in such cases relies on time interval between onset of symptoms and definitive treatment. By improving the awareness and early recognition of mesenteric ischemia will lead to improved survival in the condition.

Ischemic gastrointestinal complications of COVID-19: a systematic review on imaging presentation

Background

Limited data is available addressing gastrointestinal (GI) ischemia in coronavirus disease 2019 (COVID-19). We reviewed the clinical and radiologic features of GI ischemia and its related complications in thirty-one COVID-19 patients reported in literature.

Methods

A systematic literature review was performed using a search strategy on all studies published from January 1, 2020, to June 13, 2020, and updated on September 6, 2020, on databases from PubMed, Scopus, Embase, Web of Science, and Google Scholar. Every study with at least one presentation of COVID-19-related GI ischemia complication and one GI imaging finding was included.

Results

In total, twenty-two studies and thirty-one patients with the mean age of 59 ± 12.7 (age range: 28–80) years old were included, of which 23 (74.2%) patients were male, 7 (22.5%) female, and one unknown gender. The significant GI imaging findings include mesenteric arterial or venous thromboembolism, followed by small bowel ischemia. Nine patients (29%) presented with arterial compromise due to superior mesenteric thromboembolism, resulting in bowel ischemia. Also, 6 patients (19.3%) demonstrated occlusive thrombosis of the portal system and superior mesenteric vein. More than two-thirds of patients (20, 64.5%) required laparotomy and bowel resection. Eventually, five (16.1%) patients were discharged, of whom four cases (12.9%) readmitted. Five (16.1%) patients remained ICU hospitalized at the report time and 12 (38.7%) patients died.

Conclusion

Macrovascular arterial/venous thrombosis is identified in almost half of COVID-19 patients with bowel ischemia. Overall mortality in COVID-19 patients with GI ischemia and radiologically evident mesenteric thrombotic occlusion was 38.7% and 40%, retrospectively.

Molecular Mechanisms Underlying Intestinal Ischemia/Reperfusion Injury: Bioinformatics Analysis and In Vivo Validation

Background

Intestinal ischemia/reperfusion (I/R) injury is a serious clinical complication. This study aimed to explore the hub genes and pathways of intestinal I/R injury.

Material/Methods

GSE96733 from the GEO website was extracted to analyze the differentially expressed genes (DEGs) of intestinal I/R injured and sham-operated mice at 3 h and 6 h after surgery. The DAVID and STRING databases were used to construct functional enrichment analyses of DEGs and the protein–protein interaction (PPI) network. In Cytoscape software, cytoHubba was used to identify hub genes, and MCODE was used for module analysis. Testing by qRT-PCR detected the expression of hub genes in intestinal I/R injury. Western blot analysis detected the key proteins involved with the important pathways of intestinal I/R injury.

Results

IL-6, IL-10, CXCL1, CXCL2, and IL-1β were identified as critical upregulated genes, while IRF7, IFIT3, IFIT1, Herc6, and Oasl2 were identified as hub genes among the downregulated genes. The qRT-PCR testing showed the expression of critical upregulated genes was significantly increased in intestinal I/R injury (P<0.05), while the expression of hub downregulated genes was notably reduced (P<0.05). The proteins of CXCL1 and CXCR2 were upregulated following intestinal I/R injury (P<0.05) and the CXCL1/CXCR2 axis was involved with intestinal I/R injury.

Conclusions

The results of the present study identified IL-6, IL-10, CXCL1, CXCL2, IL-1β, IRF7, IFIT3, IFIT1, Herc6, and Oasl2 as hub genes in intestinal I/R injury and identified the involvement of the CXCL1/CXCR2 axis in intestinal I/R injury.

Aggravated intestinal ischemia‑reperfusion injury is associated with activated mitochondrial autophagy in a mouse model of diabetes

Numerous studies have reported that diabetes is associated with an increased susceptibility to cardiac ischemia- reperfusion injury; however, the mechanism underlying the role of diabetes during intestinal ischemia-reperfusion (IIR) has yet to be elucidated. The present study evaluated the intestinal pathological alterations and possible underlying mechanisms in a mouse model of type 1 diabetes mellitus with IIR. The effects of diabetes were investigated by assessing the histopathology, oxidative stress, inflammatory cytokine levels in intestine tissues and blood plasma, and protein expression levels of phosphatase and tensin homolog-induced putative kinase (PINK1), Parkin and the ratio of light chain 3B (LC3B) II/I. The results demonstrated that diabetes increased the Chiu's intestinal injury score, concentration of interleukin (IL)-1β, IL-6 and tumor necrosis factor (TNF)-α, and levels of oxidative stress. Furthermore, the alterations were more pronounced in the diabetes with IIR group. The expression levels of PINK1 and Parkin, as well as the ratio of LC3BII/I, were significantly upregulated in the IIR group compared with the Sham group. Diabetes activated PINK1 and Parkin, and increased the expression of LC3BII. Furthermore, transmission electron microscopy revealed that mitochondrial destruction and the number of autophagosomes was increased in the diabetic groups compared with the non-diabetic groups. Collectively, the results of the present study suggest that diabetes increased intestinal vulnerability to IIR by enhancing inflammation and oxidative stress. Furthermore, IIR was associated with overactivation of mitochondrial autophagy; therefore, the increased vulnerability to IIR-induced intestine damage due to diabetes may be associated with PINK1/Parkin-regulated mitochondrial autophagy.

Acute mesenteric ischaemia in refractory shock on veno-arterial extracorporeal membrane oxygenation

BACKGROUND

Acute mesenteric ischaemia is a severe complication in critically ill patients, but has never been evaluated in patients on veno-arterial extracorporeal membrane oxygenation (V-A ECMO). This study was designed to determine the prevalence of mesenteric ischaemia in patients supported by V-A ECMO and to evaluate its risk factors, as well as to appreciate therapeutic modalities and outcome.

METHODS

In a retrospective single centre study (January 2013 to January 2017), all consecutive adult patients who underwent V-A ECMO were included, with exclusion of those dying in the first 24 hours. Diagnosis of mesenteric ischaemia was performed using digestive endoscopy, computed tomography scan or first-line laparotomy.

RESULTS

One hundred and fifty V-A ECMOs were implanted (65 for post-cardiotomy shock, 85 for acute cardiogenic shock, including 39 patients after refractory cardiac arrest). Overall, median age was 58 (48-69) years and mortality 56%. Acute mesenteric ischaemia was suspected in 38 patients, with a delay of four (2-7) days after ECMO implantation, and confirmed in 14 patients, that is, a prevalence of 9%. Exploratory laparotomy was performed in six out of 14 patients, the others being too unstable to undergo surgery. All patients with mesenteric ischaemia died. Independent risk factors for developing mesenteric ischaemia were renal replacement therapy (odds ratio (OR) 4.5, 95% confidence interval (CI) 1.3-15.7, p=0.02) and onset of a second shock within the first five days (OR 7.8, 95% CI 1.5-41.3, p=0.02). Conversely, early initiation of enteral nutrition was negatively associated with mesenteric ischaemia (OR 0.15, 95% CI 0.03-0.69, p=0.02).

CONCLUSIONS

Acute mesenteric ischaemia is a relatively frequent but dramatic complication among patients on V-A ECMO.

Case report and systematic review of mesenteric artery by-pass for non-atherosclerotic mesenteric vascular disease

INTRODUCTION

Mesenteric artery re-vascularization using bypass or angioplasty is a standard of care in atherosclerotic mesenteric vascular disease. However, there are no certain guidelines for the management of non-atherosclerotic thrombophilic mesenteric vessel disease other than anti-coagulation.

CASE REPORT

We are reporting a case of a 36 years old lady with post-prandial angina and weight loss on the background of anti-phospholipid syndrome having tripple mesentric vessel occlusive disease who underwent 2 vessel aorto-mesenteric bypass. During the post-op course, patient had laparotomy with diversion ileostomy for ischemic perforation of the bowel. At present, after 6 weeks patient is recovering well with improved appetite and resolution of symptoms.

DISCUSSION

There are very few cases reported with acute on chronic mesenteric ischemia in England. Nikolas Melas et al. reported similar history in a 57 yrs old Caucasian female. Morbi AH2 highlights timely diagnosis of acute mesmeric ischemia in a 53 yrs old.

CONCLUSION

This case report is unique in a way that combined mesenteric ischemia and APS is a rare combination in a 36 years old. Mesenteric artery bypass is one of the possible solutions to thrombophilic mesenteric disease, however larger studies with longer follow up are needed.

European guidelines on chronic mesenteric ischaemia - joint United European Gastroenterology, European Association for Gastroenterology, Endoscopy and Nutrition, European Society of Gastrointestinal and Abdominal Radiology, Netherlands Association of Hepatogastroenterologists, Hellenic Society of Gastroenterology, Cardiovascular and Interventional Radiological Society of Europe, and Dutch Mesenteric Ischemia Study group clinical guidelines on the diagnosis and treatment of patients with chronic mesenteric ischaemia

Chronic mesenteric ischaemia is a severe and incapacitating disease, causing complaints of post-prandial pain, fear of eating and weight loss. Even though chronic mesenteric ischaemia may progress to acute mesenteric ischaemia, chronic mesenteric ischaemia remains an underappreciated and undertreated disease entity. Probable explanations are the lack of knowledge and awareness among physicians and the lack of a gold standard diagnostic test. The underappreciation of this disease results in diagnostic delays, underdiagnosis and undertreating of patients with chronic mesenteric ischaemia, potentially resulting in fatal acute mesenteric ischaemia. This guideline provides a comprehensive overview and repository of the current evidence and multidisciplinary expert agreement on pertinent issues regarding diagnosis and treatment, and provides guidance in the multidisciplinary field of chronic mesenteric ischaemia.

Pancreatic secretory trypsin inhibitor reduces multi-organ injury caused by gut ischemia/reperfusion in mice

Intestinal ischemia/reperfusion (I/R) injury occurs during transplantation, mesenteric arterial occlusion, trauma and shock, causing systemic inflammation, multiple organ dysfunction and high mortality. Pancreatic secretory trypsin inhibitor (PSTI), a serine protease inhibitor expressed in gut mucosa may function as a mucosal protective/repair peptide. We examined whether PSTI affected mesenteric I/R-induced injury. Hypoxia/normoxia (H/N) caused 50% drop in cell viability of AGS, RIE1 and Caco-2 cells but PSTI (10 μg/ml) given prior- or during-hypoxic period improved survival by 50% (p<0.01). Similarly, Caco-2 monolayers exposed to H/N had 300% increase in transepithelial permeability, PSTI truncated this by 50% (p<0.01). Mice underwent mesenteric I/R by clamping jejunum, causing severe mucosal injury, increased apoptotic markers and 3-fold increases in plasma IL-6, IL1β, TNFα, and tissue lipid peroxidation (MDA) and inflammatory infiltration (MPO) levels. Lungs showed similar significant injury and inflammatory infiltrate markers. Smaller increases in MDA and MPO were seen in kidney & liver. PSTI (20 mg/kg) reduced all injury markers by 50–80% (p<0.01). In vitro and in vivo studies showed PSTI reduced pro-apoptotic Caspase 3, 9 and Baxα levels, normalised Bcl2 and caused additional increases in HIF1α, VEGF and Hsp70 above rises caused by I/R alone (all p<0.01). PSTI also prevented reduction of tight junction molecules ZO1 and Claudin1 (all p<0.01) but did not affect increased ICAM-1 caused by I/R in gut or lung. PSTI may be a useful clinical target to prevent I/R injury.

The Roles of GABA in Ischemia-Reperfusion Injury in the Central Nervous System and Peripheral Organs

Ischemia-reperfusion (I/R) injury is a common pathological process, which may lead to dysfunctions and failures of multiple organs. A flawless medical way of endogenous therapeutic target can illuminate accurate clinical applications. γ-Aminobutyric acid (GABA) has been known as a marker in I/R injury of the central nervous system (mainly in the brain) for a long time, and it may play a vital role in the occurrence of I/R injury. It has been observed that throughout cerebral I/R, levels, syntheses, releases, metabolisms, receptors, and transmissions of GABA undergo complex pathological variations. Scientists have investigated the GABAergic enhancers for attenuating cerebral I/R injury; however, discussions on existing problems and mechanisms of available drugs were seldom carried out so far. Therefore, this review would summarize the process of pathological variations in the GABA system under cerebral I/R injury and will cover corresponding probable issues and mechanisms in using GABA-related drugs to illuminate the concern about clinical illness for accurately preventing cerebral I/R injury. In addition, the study will summarize the increasing GABA signals that can prevent I/R injuries occurring in peripheral organs, and the roles of GABA were also discussed correspondingly.

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.

Detection of Intestinal Tissue Perfusion by Real-Time Breath Methane Analysis in Rat and Pig Models of Mesenteric Circulatory Distress

OBJECTIVES

Methane (CH4) breath test is an established diagnostic method for gastrointestinal functional disorders. Our aim was to explore the possible link between splanchnic circulatory changes and exhaled CH4 in an attempt to recognize intestinal perfusion failure.

DESIGN

Randomized, controlled in vivo animal study.

SETTING

University research laboratory.

SUBJECTS

Anesthetized, ventilated Sprague-Dawley rats (280 ± 30 g) and Vietnamese minipigs (31 ± 7 kg).

INTERVENTIONS

In the first series, CH4 was administered intraluminally into the ileum before 45 minutes mesenteric ischemia or before reperfusion in non-CH4 producer rats to test the appearance of the gas in the exhaled air. In the porcine experiments, the superior mesenteric artery was gradually obstructed during consecutive, 30-minute flow reductions and 30-minute reperfusions achieving complete occlusion after four cycles (n = 6), or nonocclusive mesenteric ischemia was induced by pericardial tamponade (n = 12), which decreased superior mesenteric artery flow from 351 ± 55 to 182 ± 67 mL/min and mean arterial pressure from 96.7 ± 18.2 to 41.5 ± 4.6 mm Hg for 60 minutes.

MEASUREMENTS AND MAIN RESULTS

Macrohemodynamics were monitored continuously; RBC velocity of the ileal serosa or mucosa was recorded by intravital videomicroscopy. The concentration of exhaled CH4 was measured online simultaneously with high-sensitivity photoacoustic spectroscopy. The intestinal flow changes during the occlusion-reperfusion phases were accompanied by parallel changes in breath CH4 output. Also in cardiac tamponade-induced nonocclusive intestinal ischemia, the superior mesenteric artery flow and RBC velocity correlated significantly with parallel changes in CH4 concentration in the exhaled air (Pearson's r = 0.669 or r = 0.632, respectively).

CONCLUSIONS

we report a combination of in vivo experimental data on a close association of an exhaled endogenous gas with acute mesenteric macro- and microvascular flow changes. Breath CH4 analysis may offer a noninvasive approach to follow the status of the splanchnic circulation.

The interaction between CSE/H2S and the iNOS/NO-mediated resveratrol/poly(ethylene glycol)-poly(phenylalanine) complex alleviates intestinal ischemia/reperfusion injuries in diabetic rats

INTRODUCTION

The purpose of the experiment was to survey the therapeutic function of resveratrol (RES)-loaded poly(ethylene glycol)-poly(phenylalanine) (PEG-PPhe) on intestinal ischemia/reperfusion injury (II/RI) via the interaction between CSE/H₂S and iNOS/NO compared to free RES in diabetic rats.

METHODS

Diabetic rats were pretreated with 20 mg/kg of RES or the RES/PEG-PPhe complex and then subjected to 1 h of ischemia and 3 h of reperfusion. Blood and intestines were collected, intestinal pathological injury was estimated, and the contents of body weight, weights of different tissues, blood glucose, serum insulin, HOMA index, serum nitric oxide (NO) and serum sulfureted hydrogen (H₂S) were observed. The dry/wet intestine ratios, the activity of superoxide dismutase (SOD); the contents of methane dicarboxylic aldehyde (MDA), glutathione (GSH), H₂S, and NO; and the concentrations of inducible nitric oxide synthase (iNOS) and cystathionine-γ-lyase (CSE) were observed in the intestinal tissues.

RESULTS

A significant reduction of weights of different tissues, blood glucose, pathological damage, dry/wet ratios, MDA, NO, iNOS expression and a significant increasement of body weight, serum insulin, HOMA index, SOD, GSH, H₂S, CSE expression were observed in both treatment groups. However, a greater reduction of weights of different tissues, blood glucose (7.49-13.49 mmol/L for 72 h vs. the control) and pathological damage, iNOS expression, dry/wet ratios (6.14 ± 0.29 vs. 8.51 ± 0.42), MDA (5.01 ± 0.71 nmol vs. 9.98 ± 0.67 nmol), NO (0.52 ± 0.09 μmol vs. 0.99 ± 0.08 μmol in intestinal tissue; 19.29 ± 0.89 μmol vs. 45.23 ± 1.17 μmol in serum) was observed in the RES/PEG-PPhe group relative to the I/R (P < 0.01 for all); a greater increasement of body weight, serum insulin, HOMA index, SOD (39.79±1.78 U vs. 11.84 ± 1.02 U), GSH (31.25 ± 1.19 mg vs. 10.13 ± 0.64 mg), H₂S (39.52 ± 1.32 nmol vs. 13.02 ± 1.03 nmol in intestinal tissue; 9.78 ± 0.79 μmol vs. 3.11 ± 0.85 μmol in serum), CSE expression was observed in the RES/PEG-PPhe group relative to the I/R (P < 0.01 for all). In addition, aminoguanidine (AMI, iNOS inhibitor) reduced I/R injury, and dl-propargylglycine (PAG, CSE inhibitor) increased I/R injury.

CONCLUSIONS

The interaction between CSE/H2S and the iNOS/NO-mediated resveratrol/poly(ethylene glycol)-poly(phenylalanine) complex alleviates intestinal ischemia/reperfusion injuries in diabetic rats.

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

OBJECTIVES

To identify treatments likely to prevent progression towards irreversible transmural intestinal necrosis (ITIN) in acute mesenteric ischemia (AMI).

METHODS

Prospective observational cohort study from a French intestinal stroke center. Multivariate analysis using a time-dependent Cox regression model.

RESULTS

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).

CONCLUSIONS

By decreasing luminal bacterial load and translocation, oral antibiotics in addition to early revascularization might reduce progression of AMI to ITIN.

Intestinal failure in adults: Recommendations from the ESPEN expert groups

BACKGROUND & AIMS

Intestinal failure (IF) is defined as "the reduction of gut function below the minimum necessary for the absorption of macronutrients and/or water and electrolytes, such that intravenous supplementation is required to maintain health and/or growth". Functionally, it may be classified as type I acute intestinal failure (AIF), type II prolonged AIF and type III chronic intestinal failure (CIF) The ESPEN Workshop on IF was held in Bologna, Italy, on 15-16 October 2017 and the aims of this document were to highlight the current state of the art and future directions for research in IF.

METHODS

This paper represents the opinion of experts in the field, based on current evidence. It is not a formal review, but encompasses the current evidence, with emphasis on epidemiology, classification, diagnosis and management.

RESULTS

IF is the rarest form of organ failure and can result from a variety of conditions that affect gastrointestinal anatomy and function adversely. Assessment, diagnosis, and short and long-term management involves a multidisciplinary team with diverse expertise in the field that aims to reduce complications, increase life expectancy and improve quality of life in patients.

CONCLUSIONS

Both AIF and CIF are relatively rare conditions and most of the published work presents evidence from small, single-centre studies. Much remains to be investigated to improve the diagnosis and management of IF and future studies should rely on multidisciplinary, multicentre and multinational collaborations that gather data from large cohorts of patients. Emphasis should also be placed on partnership with patients, carers and government agencies in order to improve the quality of research that focuses on patient-centred outcomes that will help to improve both outcomes and quality of life in patients with this devastating condition.

Overview of Link Between Inflammatory Bowel Disease and Cardiovascular Disease

Inflammation has been shown to play an increasingly important role in the pathogenesis of atherosclerosis and in precipitating thrombotic events. Inflammatory bowel disease (IBD) is a systemic inflammatory disorder with a wide range of extraintestinal manifestations including a clinically significant increase in the risk of venous thromboembolism compared to matched controls in several studies. The data for the association between IBD and ischemic heart disease are less clear; multiple population-based studies have shown both positive and negative associations between the 2 conditions. While the systemic inflammation should theoretically increase the risk for cardiovascular disease, inflammatory bowel also potentially provides a cardioprotective effect in several ways. Patients with IBD typically enter the healthcare system at an earlier age and experience a lower incidence of obesity, hypercholesterolemia, and hyperlipidemia. Given the complex interplay among the proatherogenic, prothrombogenic, and cardioprotective effects, IBD should be taken into consideration as a nontraditional risk factor for cardiovascular disease in specific subsets of patients.

Inhibition of ubiquitin-activating enzyme protects against organ injury after intestinal ischemia-reperfusion

Intestinal ischemia-reperfusion (I/R) occurs in various clinical settings, such as transplantation, acute mesenteric arterial occlusion, trauma, and shock. I/R injury causes severe systemic inflammation, leading to multiple organ dysfunction associated with high mortality. The ubiquitin proteasome pathway has been indicated in the regulation of inflammation, particularly through the NF-κB signaling pathway. PYR-41 is a small molecular compound that selectively inhibits ubiquitin-activating enzyme E1. A mouse model of intestinal I/R injury by clamping the superior mesenteric artery for 45 min was performed to evaluate the effect of PYR-41 treatment on organ injury and inflammation. PYR-41 was administered intravenously at the beginning of reperfusion. Blood and organ tissues were harvested at 4 h after reperfusion. PYR-41 treatment improved the morphological structure of gut and lung after I/R, as judged by hematoxylin and eosin staining. It also reduced the number of apoptotic terminal deoxynucleotidyl transferase dUTP nick end-labeling-positive cells and caspase-3 activity in the organs. PYR-41 treatment decreased the expression of proinflammatory cytokines IL-6 and IL-1β as well as chemokines keratinocyte chemoattractant and macrophage inflammatory protein-2 in the gut and lung, which leads to inhibition of neutrophils infiltrating into these organs. The serum levels of IL-6, aspartate aminotransferase, and lactate dehydrogenase were reduced by the treatment. The IκB degradation in the gut increased after I/R was inhibited by PYR-41 treatment. Thus, ubiquitination may be a potential therapeutic target for treating patients suffering from intestinal I/R. NEW & NOTEWORTHY Excessive inflammation contributes to organ injury from intestinal ischemia-reperfusion (I/R) in many clinical conditions. NF-κB signaling is very important in regulating inflammatory response. In an experimental model of gut I/R injury, we demonstrate that administration of a pharmacological inhibitor of ubiquitination process attenuates NF-κB activation, leading to reduction of inflammation, tissue damage, and apoptosis in the gut and lungs. Therefore, ubiquitination process may serve as a therapeutic target for treating patients with intestinal I/R injury.

[Modern treatment of mesenteric ischemia]

Acute mesenteric ischemia is a highly morbid affliction which requires urgent care. Acute mesenteric ischemia consists in an ischemia injury of the small bowel, secondary to vascular insufficiency, either occlusive (thrombosis, embolism, arterial, venous) or non-occlusive (low flow or vasospasm). Given that the superior mesenteric artery supplies the small bowel as well as the right part of the colon, any ischemic process involving the right colon should be considered an acute mesenteric ischemia until proven otherwise. Acute mesenteric ischemia should always be suspected in the setting of a sudden, unusual and intense abdominal pain requiring opioids. Chronic mesenteric ischemia can also be revealed by postprandial abdominal pain associated with significant weight loss. The clinical presentation of mesenteric ischemia is nonspecific. Thus, a suspected diagnosis must be confirmed by imaging usually consisting in an abdominal computed tomography scan. Imaging will also provide guidance with regards to treatment decision. Organ failure, serum lactate elevation as well as bowel loop dilationper imaging are predictive of irreversible intestinal necrosis. In the presence of any of these predictive factors, surgical management should be considered. The modern treatment of mesenteric ischemia in Intestinal Stroke Centers has allowed rates of resection-free survival in nearly two-thirds of patients. The management of mesenteric ischemia relies in a combination of: (1) a medical protocol including oral/enteral antibiotics; (2) the revascularization of viable bowel and (3) the surgical resection of necrosic, non viable intestinal tissue. The inception and development of Intestinal Stroke Centers has been the cornerstone of significantly improved management and survival rates as well as crucial asset in research, specifically in the field of biomarkers associated with early diagnosis.

Neutralization of Osteopontin Ameliorates Acute Lung Injury Induced by Intestinal Ischemia-Reperfusion

Intestinal ischemia-reperfusion (I/R) is associated with acute respiratory distress syndrome. Osteopontin (OPN), a glycoprotein secreted from immune-reactive cells, plays a deleterious role in various inflammatory diseases. Considering OPN as a pro-inflammatory molecule, we hypothesize that the treatment with its neutralizing antibody (anti-OPN Ab) protects mice against intestinal I/R-induced acute lung injury (ALI). Intestinal I/R was induced in mice by superior mesenteric artery occlusion with a vascular clip. After 45 min of occlusion, the clip was removed and anti-OPN Ab (25 μg/mouse) or normal IgG isotype control (25 μg/mouse) was immediately administrated intravenously. Blood, small intestine, and lung tissues were collected at 4 h after reperfusion for various analyses. After intestinal I/R, mRNA and protein levels of OPN were significantly induced in the small intestine, lungs, and blood relative to sham-operated animals. Compared with the IgG control group, treatment of anti-OPN Ab significantly reduced plasma levels of pro-inflammatory cytokine and chemokine (IL-6 and MIP-2) and organ injury markers (AST, ALT, and LDH). The histological architecture of the gut and lung tissues in anti-OPN Ab-treated intestinal I/R-induced mice showed significant improvement versus the IgG control mice. The lung inflammation measured by the levels of IL-6, IL-1β, and MIP-2 was also significantly downregulated in the anti-OPN Ab-treated mice as compared with the IgG control mice. Besides, the lung MPO and neutrophil infiltration in anti-OPN Ab-treated mice showed significant reduction as compared with the IgG control animals. In conclusion, we have demonstrated beneficial outcomes of anti-OPN Ab treatment in protecting against ALI, implicating a novel therapeutic potential in intestinal I/R.

Open Abdomen Improves Survival in Patients With Peritonitis Secondary to Acute Superior Mesenteric Artery Occlusion

BACKGROUND

Damage control surgery and open abdomen (OA) have been extensively used in the severe traumatic patients. However, there was little information when extended to a nontrauma setting. The purpose of this study was to evaluate whether the liberal use of OA as a damage control surgery adjunct improved the clinical outcome in acute superior mesenteric artery occlusion patients.

STUDY DESIGN

A single-center, retrospective cohort review was performed in a national tertiary surgical referral center.

RESULTS

Forty-four patients received OA (OA group) and 65 patients had a primary fascial closure (non-OA group) after diagnosed as peritonitis secondary to acute superior mesenteric artery occlusion from January, 2005 to June, 2016. Revascularization was achieved through endovascular aspiration embolectomy, open embolectomy, or percutaneous stent. No difference of bowel resection length was found between groups in the first emergency surgery. However, more non-OA patients (35.4%) required a second-look enterectomy to remove the residual bowel ischemia than OA patients (13.6%, P<0.05). OA was closed within a median of 7 days (4 to 15 d). There was a mean of 134 cm residual alive bowel in OA, whereas 96 cm in non-OA. More non-OA patients suffered from intra-abdominal sepsis (23.1% vs. 6.8%, P<0.01), intra-abdominal hypertension (31% vs. 0, P<0.01), and acute renal failure (53.8% vs. 31.8%, P<0.05) than OA group after surgery. Short-bowel syndrome occurred infrequently in OA than non-OA patients (9.1% vs. 36.9%, P<0.01). OA significantly decreased the 30-day (27.3% vs. 52.3%, P<0.01) and 1-year mortality rate (31.8 % vs. 61.5%, P<0.01) compared with non-OA group.

CONCLUSIONS

Liberal use of OA, as a damage control adjunct avoided the development of intra-abdominal hypertension, reduced sepsis-related complication, and improved the clinical outcomes in peritonitis secondary to acute SMA occlusion.

Diagnosis biomarkers in acute intestinal ischemic injury: so close, yet so far

Acute intestinal ischemic injury (i3) is a life-threatening condition with disastrous prognosis, which is currently difficult to diagnose at the early stages of the disease; a rapid diagnosis is mandatory to avoid irreversible ischemia, extensive bowel resection, sepsis and death. The overlapping protein expression of liver and gut related to the complex physiopathology of the disease, the heterogeneity of the disease and its relative rarity could explain the lack of a useful early biochemical marker of i3. Apart from non-specific biological markers of thrombosis, hypoxia inflammation, and infection, several more specific biomarkers in relation with the gut barrier dysfunction, the villi injury and the enterocyte mass have been used in the diagnosis of acute i3. It includes particularly D-lactate, intestinal fatty acid-binding protein (FABP) and citrulline. Herein, we will discuss leading publications concerning these historical markers that point out the main limitations reagrding their use in routine clinical practice. We will also introduce the first and limited results arising from omic studies, underlying the remaining effort that needs to be done in the field of acute i3 biological diagnosis, which remains a challenge.

Acute mesenteric ischemia: guidelines of the World Society of Emergency Surgery

Acute mesenteric ischemia (AMI) is typically defined as a group of diseases characterized by an interruption of the blood supply to varying portions of the small intestine, leading to ischemia and secondary inflammatory changes. If untreated, this process will eventuate in life threatening intestinal necrosis. The incidence is low, estimated at 0.09–0.2% of all acute surgical admissions. Therefore, although the entity is an uncommon cause of abdominal pain, diligence is always required because if untreated, mortality has consistently been reported in the range of 50%. Early diagnosis and timely surgical intervention are the cornerstones of modern treatment and are essential to reduce the high mortality associated with this entity. The advent of endovascular approaches in parallel with modern imaging techniques may provide new options. Thus, we believe that a current position paper from World Society of Emergency Surgery (WSES) is warranted, in order to put forth the most recent and practical recommendations for diagnosis and treatment of AMI. This review will address the concepts of AMI with the aim of focusing on specific areas where early diagnosis and management hold the strongest potential for improving outcomes in this disease process.

Some of the key points include the prompt use of CT angiography to establish the diagnosis, evaluation of the potential for revascularization to re-establish blood flow to ischemic bowel, resection of necrotic intestine, and use of damage control techniques when appropriate to allow for re-assessment of bowel viability prior to definitive anastomosis and abdominal closure.

Europium-Doped Cerium Oxide Nanoparticles Limit Reactive Oxygen Species Formation and Ameliorate Intestinal Ischemia-Reperfusion Injury

Accumulating evidence suggests that ischemia-reperfusion-induced injury is associated with the formation of reactive oxygen species (ROS). This study demonstrates the therapeutic effectiveness of novel europium-doped cerium oxide nanoparticles (Eu-doped Ceria NPs) as ROS scavengers in a mouse model of intestinal ischemia-reperfusion-induced injury. An increased production of superoxide radicals is detected in the intestine throughout the ischemia stage and again after initiating reperfusion. These changes in superoxide radical formation are associated with the induction of inflammatory cytokines in the intestine. This study further shows that Eu-Ceria NPs exhibit superoxide scavenging activity in vitro. Importantly, administration of Eu-Ceria NPs into the intestinal lumen during the onset of ischemia effectively blocks superoxide accumulation, reduces the expression of IL-1b, and ameliorates the intestinal pathology. These results suggest that early increased production of ROS during the ischemia-reperfusion promotes intestinal pathology and that mucosal delivery of Eu-Ceria NPs may be a potential therapeutic approach to block ROS accumulation and ameliorate the severity of intestinal disease.

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

OBJECTIVES

To identify predictive factors for irreversible transmural intestinal necrosis (ITIN) in acute mesenteric ischemia (AMI) and establish a risk score for ITIN.

METHODS

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.

RESULTS

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.

CONCLUSIONS

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.