Diagnostic performance of plasma biomarkers in patients with acute intestinal ischaemia

Longitudinal analysis of serum intestinal fatty acid-binding protein in a patient with non-occlusive mesenteric ischemia following brachial plexus block-induced hypotension: a case study

Intestinal fatty acid-binding protein (I-FABP) is a promising biomarker for small-bowel ischemia including non-occlusive mesenteric ischemia (NOMI). A 75-year-old woman with diabetic nephropathy sustained a distal radius fracture. Two days later, she underwent a brachial plexus block to facilitate orthopedic surgery, which resulted in hypotension. Despite prompt fluid resuscitation and ephedrine administration, the patient developed abdominal pain. Contrast-enhanced computed tomography revealed hepatic portal venous gas, but no direct evidence of small-bowel ischemia. The gastrointestinal surgery team opted for cautious in-hospital observation overnight. Unfortunately, the patient's condition significantly worsened the following day, prompting an urgent laparotomy. Surgery confirmed ileal segment necrosis, macroscopically characterized by a distinctive geographic pattern. Retrospective analysis of stored serum samples using a human enzyme-linked immunosorbent assay demonstrated that I-FABP levels were moderately elevated (7.2 ng/mL) at the initial outpatient visit for the fracture, peaked (17.9 ng/mL) at the clinical onset of NOMI, and returned to normal (0.7 ng/mL) by postoperative day 2. Serum I-FABP levels correlated with the progression of NOMI, showing potential as an early detection marker. However, the longitudinal analysis of serum I-FABP also highlighted significant challenges of this biomarker, including the influence of renal function and the importance of sampling timing.

Nonocclusive Mesenteric Ischemia: A Review for Interventional Radiologists

Nonocclusive mesenteric ischemia (NOMI) is a condition characterized by segmental or discontinuous mesenteric ischemia and intestinal necrosis without an organic obstruction in the mesenteric vessels. Diagnosis is challenging, and early intervention is crucial for improving patient outcomes. Various factors such as background factors, symptoms, biomarkers, and imaging techniques contribute to the diagnosis. Ensuring an early diagnosis and prompt treatment is of paramount importance. Although studies reported on the effectiveness of intra-arterial vasodilator infusion therapy as an endovascular treatment, its future role remains uncertain. Therefore, this review primarily aimed to provide a comprehensive summary of the advancements in the current state of NOMI management, with a specific emphasis on the implementation of endovascular therapy.

Interventional Radiology in Treating Acute Mesenteric Arterial Occlusion: A Narrative Review

Acute mesenteric arterial occlusion, resulting from impaired blood flow in the superior mesenteric artery, is classified into embolism and thrombosis; both conditions lead to rapid intestinal ischemia, with a high mortality rate of >30% within 30 days. A multidisciplinary treatment approach, including prompt revascularization, necrotic intestinal tract resection, intensive postoperative care, and recurrence prevention, is crucial for managing acute mesenteric arterial occlusion. Recent meta-analyses have indicated that endovascular treatments result in lower bowel resection and mortality rates than open revascularization. As a minimally invasive treatment option, endovascular therapy can become prevalent in the aging population. Interventional radiologists who provide diagnostic imaging and endovascular procedures must understand the disease and play a central role in the treatment team.

A review of gut failure as a cause and consequence of critical illness

In critical illness, all elements of gut function are perturbed. Dysbiosis develops as the gut microbial community loses taxonomic diversity and new virulence factors appear. Intestinal permeability increases, allowing for translocation of bacteria and/or bacterial products. Epithelial function is altered at a cellular level and homeostasis of the epithelial monolayer is compromised by increased intestinal epithelial cell death and decreased proliferation. Gut immunity is impaired with simultaneous activation of maladaptive pro- and anti-inflammatory signals leading to both tissue damage and susceptibility to infections. Additionally, splanchnic vasoconstriction leads to decreased blood flow with local ischemic changes. Together, these interrelated elements of gastrointestinal dysfunction drive and then perpetuate multi-organ dysfunction syndrome. Despite the clear importance of maintaining gut homeostasis, there are very few reliable measures of gut function in critical illness. Further, while multiple therapeutic strategies have been proposed, most have not been shown to conclusively demonstrate benefit, and care is still largely supportive. The key role of the gut in critical illness was the subject of the tenth Perioperative Quality Initiative meeting, a conference to summarize the current state of the literature and identify key knowledge gaps for future study. This review is the product of that conference.

The Role of I-FABP, REG3α, sCD14-ST, and LBP as Indicators of GI Tract Injury in MODS Patients

Background/Objectives: The aim of this study was to evaluate potential biomarkers of bacterial translocation (lipopolysaccharide-binding protein (LBP) and soluble CD14 subtype (sCD14-ST)) and intestinal wall damage (intestinal fatty acid binding protein (I-FABP), Zonulin, and regenerating islet-derived protein-3α (REG3α)) in patients with multiple organ dysfunction syndrome (MODS). Methods: The study involved 327 patients divided into two groups: Group 1 comprised 227 patients with MODS (main group), while Group 2 comprised 100 patients with identical pathologies but without MODS (control group). To examine these biomarkers in the blood, venous blood was taken in the control group on the day of admission to the hospital, in patients with MODS on the first day of MODS staging, and later on Days 3 and 7 of its development. Levels of these markers in blood serum were determined by enzyme-linked immunosorbent assays according to the manufacturers' instructions. Results: In the control group, values of all the investigated markers were lower than in the group of MODS patients (p < 0.0001). In the main group, the mortality rate was 44.9% (n = 102). The values of sCD14-ST on Day 1 and of I-FABP and REG3α on Days 1 and 3 were higher in deceased MODS patients (p < 0.05), while LBP levels on Day 7 were conversely lower in the deceased patients (p = 0.006). SOFA and APACHE II scores were higher in the deceased patients (p < 0.0001). Conclusions: In MODS patients, the increased I-FABP, REG3α, and sCD14-ST but decreased LBP levels may indicate increased intestinal wall permeability and bacterial translocation, which may exacerbate the course of multiple organ dysfunction and increase the risk of mortality. Despite the limitations of this study, the studied potential biomarkers can be considered noteworthy candidates for identifying MODS patients at high risk of mortality.

Development and validation of a nomogram model to predict the risk of strangulated intestinal obstruction

To develop and validate a nomogram model for discriminating simple intestinal obstruction and strangulated intestinal obstruction, thus providing objective evidence for clinical decision-making. Following pre-established inclusion and exclusion criteria, a retrospective analysis was conducted on the clinical data of 560 patients diagnosed with intestinal obstruction who were admitted to the Emergency Surgery Department of the First Affiliated Hospital of Anhui Medical University between January 1, 2020, and December 31, 2022. The data was subsequently split into a training cohort (n = 393) and a validation cohort (n = 167) using a 7:3 ratio. To identify independent risk and protective factors associated with strangulated intestinal obstruction, a multivariate logistic regression analysis was employed. Based on the identified factors, a nomogram prediction model was constructed. The model's discriminatory ability was assessed using the receiver operating characteristic (ROC) curve, the area under the curve (AUC), and the corrected C-index. The Hosmer-Lemeshow test was utilized to evaluate the model's goodness of fit in both the training and validation cohorts. Calibration curves were generated to assess the model's accuracy in predicting the probability of strangulated intestinal obstruction. Finally, decision curve analysis (DCA) was performed to evaluate the model's potential clinical utility. Multivariate logistic regression analysis identified neutrophil percentage, peritoneal irritation sign, and abdominal fluid as independent risk factors for strangulated intestinal obstruction, while albumin emerged as an independent protective factor. These factors were incorporated into the nomogram, demonstrating high discrimination (AUC of 0.842[95%CI: 0.787-0.897] in the training set and 0.839 [95%CI: 0.742-0.937] in the validation set) and good calibration. The corrected C-index further supported the model's performance in the training (0.833) and validation (0.813) cohorts. The Hosmer-Lemeshow test results (p = 0.759 and p = 0.505, respectively) indicated a good model fit in both cohorts. Calibration curves confirmed the close agreement between the nomogram predictions and actual observations. Finally, DCA corroborated the model's net clinical benefit. The comprehensive nomogram developed in this study emerged as a promising and convenient tool for evaluating the risk of strangulated intestinal obstruction, thereby aiding clinicians in screening the high-risk population.

Prostaglandin E-major urinary metabolites as a new biomarker for acute mesenteric ischemia

BACKGROUND

Acute mesenteric ischemia (AMI) is an emergent vascular disease caused by cessation of the blood supply to the small intestine. Despite advances in the diagnosis, intervention, and surgical procedures, AMI remains a life-threatening condition. Prostaglandin E2 major urinary metabolite (PGE-MUM), the urinary metabolite of prostaglandin E2, is known to be stable in urine and has been suggested to be a valuable biomarker for intestinal mucosal inflammation, such as ulcerative colitis. We therefore investigated whether or not PGE-MUM levels reflect the degree of ischemia in an intestinal ischemia-reperfusion model.

METHODS

Male rats were used to establish a superior mesenteric artery occlusion (SMAO) group, in which the superior mesenteric artery was clamped, and a sham group. The clamping times in the SMAO group were either 30 minutes or 60 minutes, and reperfusion times were either 3 hours or 6 hours, after which PGE-MUM values were measured.

RESULTS

The histological injury score of the SMAO (30-minute ischemia and 6-hour reperfusion group, 1.8 ± 0.4; 60-minute ischemia and 6-hour reperfusion group, 4.7 ± 0.5) and were significantly greater than that of the sham group (0.4 ± 0.7, p < 0.05). The PGE-MUM levels in the SMAO group (30-minutes ischemia and 6-hour reperfusion group, 483 ± 256; 60-minutes ischemia and 6-hour reperfusion group, 889 ± 402 ng/mL) were significantly higher than in the sham group (30-minute and 6-hour observation group, 51 ± 20; 60-minute and 6-hour observation group, 73 ± 32 ng/mL; p < 0.05). Furthermore, the PGE-MUM value was corrected by the concentration of urinary creatinine (Cr). The PGE-MUM/urinary Cr levels in the SMAO group were also significantly higher than in the sham group ( p < 0.05).

CONCLUSION

We found that intestinal ischemia-reperfusion increased urinary PGE-MUM levels depending on the ischemic time. This suggests the potential utility of PGE-MUM as a noninvasive marker of intestinal ischemia.

Is there a faster and easier method for assessing the severity of acute mesenteric ischemia?

Acute mesenteric ischemia (AMI) is a potentially fatal abdominal emergency. The estimation of the severity of AMI is of great importance since changes in disease severity may have different impacts on the treatment options. This study aims to define laboratory and radiological parameters that can successfully predict the severity of AMI. Data from 100 patients who were treated conservatively and underwent an operation with a diagnosis of AMI between the years 2010 and 2019 were reviewed. The patients were divided into 3 groups as those treated with a conservative approach (group 1), those with partial intestinal ischemia (group 2), and those with complete intestinal ischemia (group 3) according to the pathology results. Laboratory findings of the patients were recorded and matched with radiological findings. The white blood cell (WBC) count, neutrophil (NEUT) count, neutrophil/lymphocyte ratio, and C-reactive protein/albumin ratios were the considered distinctive parameters for distinguishing the third group from the first group. However, the same result cannot be applied to the first and the second groups since only the WBC and NEUT counts showed distinctive performance. The measurement of neutrophil/lymphocyte ratio, WBC, NEUT, and albumin levels can be used to predict the severity of AMI. We believe that evaluating these laboratory parameters will greatly prevent possible morbidity and mortality in the patient. Also, we were able to observe that the parameters used in predicting AMI severity can be verified with rapid and low-cost radiological imaging techniques.

Developing and validating a nomogram for early predicting the need for intestinal resection in pediatric intussusception

Purpose

Develop and validate a nomogram for predicting intestinal resection in pediatric intussusception suspecting intestinal necrosis.

Patients & methods

Children with intussusception were retrospectively enrolled after a failed air-enema reduction in the outpatient setting and divided into two groups: the intestinal resection group and the non-intestinal resection group. The enrolled cases were randomly selected for training and validation sets with a split ratio of 3:1. A nomogram for predicting the risk of intestinal resection was visualized using logistic regression analysis with calibration curve, C-index, and decision curve analysis to evaluate the model.

Results

A total of 547 cases were included in the final analysis, of which 414 had non-intestinal necrosis and 133 had intestinal necrosis and underwent intestinal resection. The training set consisted of 411 patients and the validation cohort included 136 patients. Through forward stepwise regression, four variables (duration of symptoms, C-reaction protein, white blood cells, ascites) were selected for inclusion in the nomogram with a concordance index 0.871 (95% confidence interval: 0.834-0.908).

Conclusion

We developed a nomogram for predicting intestinal resection in children with intussusception suspecting intestinal necrosis after a failed air-enema based on multivariate regression. This nomogram could be directly applied to facilitate predicting intestinal resection in pediatric intussusception suspecting necrosis.

[Epidemiology and diagnostics of mesenteric ischemia]

BACKGROUND

Mesenteric ischemia is a life-threatening condition with a complex etiology and diagnostics.

OBJECTIVE

Etiology, incidence, symptoms, and diagnostics of acute and chronic mesenteric ischemia.

MATERIAL AND METHODS

Literature search via PubMed with a focus on studies on the epidemiology and diagnostics of mesenteric ischemia and analysis of existing international guidelines.

RESULTS

The incidence of acute mesenteric ischemia is given as 0.63-12.9 per 100,000 people per year. There are no sufficiently reliable figures for chronic mesenteric ischemia, but an incidence of up to 3 per 100,000 inhabitants per year is generally assumed. The three-phase computed tomography has the highest diagnostic specificity and sensitivity.

CONCLUSION

In the presence of risk factors acute and chronic mesenteric ischemia should be considered as differential diagnoses in the presence of abdominal pain using three-phase computed tomography.

The Diagnostic Value of Biomarkers in Acute Mesenteric Ischaemia Is Insufficiently Substantiated: A Systematic Review

OBJECTIVE

There is an urgent need for accurate biomarkers to support timely diagnosis of acute mesenteric ischaemia (AMI) and thereby improve clinical outcomes. With this systematic review, the aim was to substantiate the potential diagnostic value of biomarkers for arterial occlusive AMI.

DATA SOURCES

The Pubmed, Embase, and the Cochrane Library electronic databases were searched.

REVIEW METHODS

A systematic review of the literature has been conducted to define the potential diagnostic value of biomarkers for arterial occlusive AMI. All studies including ≥ 10 patients describing biomarkers for macrovascular occlusive AMI between 1950 and 17 February 2023 were identified within the Pubmed, Embase, and the Cochrane Library electronic databases. There were no restrictions to any particular study design, but letters and editorials were excluded. The QUADAS-2 tool was used for the critical appraisal of quality. The study protocol was registered on Prospero (CRD42021254970).

RESULTS

Fifty of 4334 studies were eligible for inclusion in this review. Ninety per cent of studies were of low quality. A total of 60 biomarkers were identified, with 24 in two or more studies and 15 in five or more studies. There was variation in reported units, normal range, and cut off values. Meta-analysis was not possible due to study heterogeneity. Biomarkers currently recommended by the European Journal of Vascular and Endovascular Surgery, European Society for Trauma and Emergency Surgery 2016, and World Society of Emergency Surgery 2017 guidelines also had heterogeneous low quality data for use in the diagnosis of AMI.

CONCLUSION

This systematic review demonstrates high heterogeneity and low quality of the available evidence on biomarkers for arterial occlusive AMI. No clinical conclusions can be drawn on a biomarker or combination of biomarkers for patients suspected of arterial occlusive AMI. Restraint is advised when rejecting or determining AMI solely based on biomarkers.

The Impact of Biomarkers on the Early Detection of Acute Mesenteric Ischemia

BACKGROUND

acute mesenteric ischemia (AMI) is a life-threatening condition that is caused by inadequate blood flow through the mesenteric vessel and is related to high mortality rates due to systemic complications. This study aims to systematically review the available literature concerning the major findings of possible biomarkers for early detection of acute mesenteric ischemia in the human population.

METHODS

studies that measured the performance of biomarkers during acute mesenteric ischemia were identified with the search of PubMed, Embase, Medline, and Cochrane library.

RESULTS

from a total of 654 articles, 46 articles examining 14 different biomarkers were filtered, falling within our inclusion criteria. Intestinal fatty acid-binding protein (I-FABP) was the most commonly researched biomarker regarding AMI, with sensitivity ranging from 61.5% to 100% and specificity ranging from 40% to 100%. The second most commonly researched biomarker was D-dimer, with a sensitivity of 60-100% and a specificity of 18-85.71%. L-lactate had a sensitivity of 36.6-90.91% and a specificity of 64.29-96%. Several parameters within the blood count were examined as potential markers for AMI, including NLR, PLR, MPV, RDW, DNI, and IG. Citrulline, interleukin 6 (IL-6), and procalcitonin (PCT) were the least-researched biomarkers.

CONCLUSION

different biomarkers showed different accuracies in detecting AMI. I-FABP and D-dimer have been the most researched and shown to be valuable in the diagnosis of AMI, whereas L-lactate could be used as an additional tool. Ischemia-modified albumin (IMA), alpha glutathione S-transferase (αGST), interleukin 6 (IL-6), and citrulline showed potential use in their respective studies. However, further research needs to be done on larger sample sizes and with controls to reduce bias. Several studies showed that neutrophil-lymphocyte ratio (NLR), platelet-lymphocyte ratio (PLR), mean platelet volume (MPV), red-cell distribution width (RDW), delta neutrophil index (DNI), and immature granulocytes (IGs) might be useful, as well at the same time be widely distributed and affordable in combination with other markers presenting higher specificity and sensitivity.

Exosomal circEZH2_005, an intestinal injury biomarker, alleviates intestinal ischemia/reperfusion injury by mediating Gprc5a signaling

Intestinal ischemia/reperfusion (I/R) injury is a severe clinical condition without optimal diagnostic markers nor clear molecular etiological insights. Plasma exosomal circular RNAs (circRNAs) are valuable biomarkers and therapeutic targets for various diseases, but their role in intestinal I/R injury remains unknown. Here we screen the expression profile of circRNAs in intestinal tissue exosomes collected from intestinal I/R mice and identify circEZH2_005 as a significantly downregulated exosomal circRNA. In parallel, circEZH2_005 is also reduced in the plasma of clinical cardiac surgery patients who developed postoperative intestinal I/R injury. Exosomal circEZH2_005 displays a significant diagnostic value for intestinal injury induced by I/R. Mechanistically, circEZH2_005 is highly expressed in intestinal crypt cells. CircEZH2_005 upregulation promotes the proliferation of Lgr5+ stem cells by direct interaction with hnRNPA1, and enhanced Gprc5a stability, thereby alleviating I/R-induced intestinal mucosal damage. Hence, exosomal circEZH2_005 may serve as a biomarker for intestinal I/R injury and targeting the circEZH2_005/hnRNPA1/Gprc5a axis may be a potential therapeutic strategy for intestinal I/R injury.

Diagnostic accuracy of biomarkers to detect acute mesenteric ischaemia in adult patients: a systematic review and meta-analysis

BACKGROUND

Acute mesenteric ischaemia (AMI) is a disease with different pathophysiological mechanisms, leading to a life-threatening condition that is difficult to diagnose based solely on clinical signs. Despite widely acknowledged need for biomarkers in diagnosis of AMI, a broad systematic review on all studied biomarkers in different types of AMI is currently lacking. The aim of this study was to estimate the diagnostic accuracy of all potential biomarkers of AMI studied in humans.

METHODS

A systematic literature search in PubMed, The Cochrane Library, Web of Science and Scopus was conducted in December 2022. Studies assessing potential biomarkers of AMI in (at least 10) adult patients and reporting their diagnostic accuracy were included. Meta-analyses of biomarkers' sensitivity, specificity, and positive and negative likelihood ratios were conducted. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines were followed, and the study quality was assessed with the QUADAS-2 tool.

RESULTS

Seventy-five studies including a total of 9914 patients assessed 18 different biomarkers in serum/plasma and one in urine (each reported in at least two studies), which were included in meta-analyses. None of the biomarkers reached a conclusive level for accurate prediction. The best predictive value overall (all studies with any type and stage of AMI pooled) was observed for Ischaemia-modified albumin (2 studies, sensitivity 94.7 and specificity 90.5), interleukin-6 (n = 4, 96.3 and 82.6), procalcitonin (n = 6, 80.1 and 86.7), and intestinal fatty acid-binding protein (I-FABP) measured in serum (n = 16, 73.9 and 90.5) or in urine (n = 4, 87.9 and 78.9). In assessment of transmural mesenteric ischaemia, urinary I-FABP (n = 2, 92.3 and 85.2) and D-dimer (n = 3, 87.6 and 83.6) showed moderate predictive value. Overall risk of bias was high, mainly because of selected study populations and unclear timings of the biomarker measurements after onset of symptoms. Combinations of biomarkers were rarely studied, not allowing meta-analyses.

CONCLUSIONS

None of the studied biomarkers had sufficient sensitivity and specificity to diagnose AMI, although some biomarkers showed moderate predictive accuracy. Future studies should focus on timing of measurements of biomarkers, distinguishing between early stage and transmural necrosis, and between different types of AMI. Additionally, studies on combinations of biomarkers are warranted. PROSPERO registration: CRD42022379341.

Exploring I-FABP, endothelin-1 and L-lactate as biomarkers of acute intestinal necrosis: a case-control study

OBJECTIVE

Acute intestinal necrosis (AIN) is a disease with devastating high mortality. AIN due to obstructed arterial blood flow has a blurred clinical presentation. Timely diagnosis is paramount, and a blood-based biomarker is warranted to increase patient survival. We aimed to assess intestinal fatty acid binding protein (I-FABP) and endothelin-1 as diagnostic biomarkers for AIN. To our knowledge, this is the first study exploring endothelin-1 in AIN patients from a general surgical population.

DESIGN

We conducted a single-centre nested case-control study comparing acutely admitted AIN patients to age- and sex-matched non-AIN patients during 2015-2016. I-FABP and endothelin-1 were analysed using an enzyme-linked immunosorbent assay. L-lactate levels were also measured in all patients. Cut-offs were estimated using receiver operator characteristic curves, and the diagnostic performance was estimated using the area under the receiver operator characteristic curve (AUC).

RESULTS

We identified 43 AIN patients and included 225 matched control patients. Median levels of I-FABP, endothelin-1 and L-lactate were 3550 (IQR: 1746-9235) pg/ml, 3.91 (IQR: 3.33-5.19) pg/ml and 0.92 (IQR: 0.74-1.45) mM in AIN patients and 1731 (IQR: 1124-2848) pg/ml, 2.94 (IQR: 2.32-3.82) pg/ml and 0.85 (IQR: 0.64-1.21) mM in control patients, respectively. The diagnostic performances of endothelin-1 and of I-FABP + endothelin-1 combined were moderate. Endothelin-1 alone revealed an AUC of 0.74 (0.67; 0.82). The sensitivity and specificity of endothelin-1 were 0.81 and 0.64, respectively.

CONCLUSION

I-FABP and endothelin-1 are promising biomarkers for AIN, with moderate diagnostic performance compared with the commonly used biomarker L-lactate.

PREREGISTRATION

ClinicalTrials.gov: NCT05665946.

Dysfunction of the intestinal physical barrier in the intestinal inflammation of tongue sole, Cynoglossus semilaevis, induced by Shewanella algae infection

Bacterial intestinal inflammation occurs frequently in cultured fish. However, research on the dysfunction of the intestinal physical barrier in fish intestinal inflammation is scarce. In this study, intestinal inflammation in tongue sole Cynoglossus semilaevis was induced by Shewanella algae and the intestinal permeability was investigated. Gene expression patterns in inflammatory factors, tight junction molecules, and keratins 8 and 18 in the intestines were further explored. Histological examinations of the middle intestines showed that S. algae induced pathological lesions of intestinal inflammation and significantly increased the total number of mucous cells (p < 0.01). Ultrastructural observation in the middle intestines showed that intercellular spaces between epithelial cells were significantly wider in infected fish compared with the control (p < 0.01). The positive result of fluorescence in situ hybridization confirmed the presence of S. algae in the intestine. Enhanced Evans blue exudation and increased levels of serum d-lactate and intestinal fatty acid binding protein were suggestive of increased intestinal barrier permeability. The mRNA levels of four pro-inflammatory cytokines, namely IL-6, IL-8, IL-β, and TNF-α, were significantly increased after S. algae infection at most tested time points (p < 0.01 or p < 0.05), while there was an alternating increasing and decreasing trend in the gene expression patterns of IL-10, TGF-β, TLR-2, AP-1, and CASP-1. The mRNA expression of tight junction molecules (claudin-1, claudin-2, ZO-1, JAM-A, and MarvelD3) and keratins 8 and 18 in the intestines was significantly decreased at 6, 12, 24, 48, or 72 h post infection (p < 0.01 or p < 0.05). In conclusion, S. algae infection induced intestinal inflammation accompanied by increased intestinal permeability in tongue sole, and tight junction molecules and keratins were probably associated with the pathological process.

Basic demographic characteristics and prevalence of comorbidities in acute mesenteric ischemia: a systematic review and proportional meta-analysis

PURPOSE

The aim of this systematic review and meta-analysis was to examine and assess the basic demographic characteristics and prevalence of comorbidities in acute mesenteric ischemia (AMI) and its various subtypes.

PATIENTS AND METHODS

A literature search was conducted by using the databases PubMed, EMBASE, and Google Scholar (to June 1, 2022). Random-effects or fixed-effects models were selected to pool means and proportions and their corresponding 95% confidence intervals (CI), based on heterogeneity between studies. The results of meta-analyses for basic demographic characteristics and prevalence (proportions) of each specific comorbidities of acute mesenteric ischemia (AMI) and its various subtypes were described.

RESULTS

Ninety-nine studies were included in the meta-analysis, including 17,103 patients with AMI. Furthermore, 7941 patients with subclass diagnoses of AMI were identified, including 3,239 patients with arterial occlusive mesenteric ischemia (AOMI), 2,977 patients with nonocclusive mesenteric ischemia (NOMI), and 1,725 patients with mesenteric venous thrombosis (MVT). As a surgical emergency, AMI is associated with older patients and a high likelihood of multisystem comorbidities. Comorbidities of AMI involved multiple systemic diseases, including cardiovascular disease, endocrine and metabolic diseases, kidney diseases, digestive diseases, respiratory diseases, cerebrovascular diseases, vascular diseases, and cancer.

CONCLUSION

The basic demographic characteristics and the prevalence of comorbidities of different subtypes of AMI are different. The management of comorbidities should be an essential part of improving the prognosis of AMI patients and may contribute to precise prevention of AMI.

A new clinical severity score for the management of acute small bowel obstruction in predicting bowel ischemia: a cohort study

BACKGROUND

Small bowel obstruction (SBO) is a common hospital admission diagnosis. Identification of patients who will require a surgical resection because of a nonviable small bowel remains a challenge. Through a prospective cohort study, the authors aimed to validate risk factors and scores for intestinal resection, and to develop a practical clinical score designed to guide surgical versus conservative management.

PATIENTS AND METHODS

All patients admitted for an acute SBO between 2004 and 2016 in the center were included. Patients were divided in three categories depending on the management: conservative, surgical with bowel resection, and surgical without bowel resection. The outcome variable was small bowel necrosis. Logistic regression models were used to identify the best predictors.

RESULTS

Seven hundred and thirteen patients were included in this study, 492 in the development cohort and 221 in the validation cohort. Sixty-seven percent had surgery, of which 21% had small bowel resection. Thirty-three percent were treated conservatively. Eight variables were identified with a strong association with small bowel resection: age 70 years of age and above, first episode of SBO, no bowel movement for greater than or equal to 3 days, abdominal guarding, C-reactive protein greater than or equal to 50, and three abdominal computer tomography scanner signs: small bowel transition point, lack of small bowel contrast enhancement, and the presence of greater than 500 ml of intra-abdominal fluid. Sensitivity and specificity of this score were 65 and 88%, respectively, and the area under the curve was 0.84 (95% CI: 0.80-0.89).

CONCLUSION

The authors developed and validated a practical clinical severity score designed to tailor management of patients presenting with an SBO.

Utility of Serum L-lactate in Identifying Ischemia in Acute Intestinal Obstruction: A Prospective Observational Study

Introduction In cases of intestinal obstruction, increasing luminal dilatation compromises bowel wall perfusion, eventually resulting in intestinal ischemia and bowel necrosis in advanced cases. Elevated L-lactate, as a biomarker of ischemia, may indicate the presence of bowel ischemia in cases of obstruction. The objective of this study was to evaluate the value of serum L-lactate measurement in predicting the presence of intraoperatively observed intestinal ischemia in patients with acute intestinal obstruction. Methods Patients diagnosed with acute intestinal obstruction were prospectively studied over an 18-month period. Serum L-lactate values were assayed twice: at the time of presentation and following appropriate fluid resuscitation. Receiver operating characteristic (ROC) curve analysis was applied to determine the predictive value of serum L-lactate in detecting intestinal ischemia. Results One hundred forty-four cases of intestinal obstruction were included in this study, of which 91 underwent operative intervention. Intestinal ischemia was identified in 52 cases and categorized intra-operatively as reversible (n = 33) and irreversible (n = 19). ROC analysis showed a good predictive value of serum L-lactate after fluid resuscitation for irreversible intestinal ischemia (area under the curve (AUC) = 0.884, 95% confidence interval (CI), 0.812-0.956). An L-lactate cut-off of 19.1 mg/dL following fluid resuscitation was determined to have a sensitivity of 89.5%, a specificity of 72.9%, a positive predictive value of 46.6%, and a negative predictive value of 96.3% for gangrenous bowel. Conclusion Serum L-lactate is a good predictive tool for identifying intestinal ischemia during the management of intestinal obstruction. Serum L-lactate after resuscitation showed better predictive value for ischemic bowel.

Fatty acid binding protein 1 (FABP1) and fatty acid binding protein 2 (FABP2) as a link between diabetic nephropathy and subclinical atherosclerosis in children and adolescents with type 1 diabetes

BACKGROUND

Diabetic nephropathy is a major cause of morbidity and mortality in type 1 diabetes mellitus (T1DM). Fatty acid binding proteins (FABP1 and FABP2) play a role in the development and progression of chronic kidney disease including type 2 diabetes mellitus.

AIM

We assessed serum FABP1 and FABP2 levels in children and adolescents with T1DM as potential markers for diabetic nephropathy and their relation to carotid intima media thickness (CIMT).

METHODS

Sixty patients with T1DM were divided into 2 groups according to the presence of nephropathy and compared with 30 healthy controls. CIMT, fasting blood glucose (FBG), hemoglobin A1c (HbA1c), urinary albumin creatinine ratio (UACR), fasting lipid profile and serum FABP1 and FABP2 levels were assessed.

RESULTS

FABP1 and FABP2 levels were significantly higher among type 1 diabetic patient with and without nephropathy compared with healthy controls with the highest levels among patients with nephropathy (p < 0.001). There were significant positive correlations between FABP1 and FABP2 and each of systolic blood pressure, CIMT, FBG, HbA1c and total cholesterol among T1DM patients. FABP1 was negatively correlated to glomerular filtration rate. Multivariable linear regression analysis showed that systolic blood pressure, CIMT, FBG and HbA1c were the significant independent variables related to FABP1 levels in type 1 diabetic patients with nephropathy. ROC curve analysis was performed to determine the cutoff value of FABP1 and FABP2 that could detect nephropathy.

CONCLUSION

FABP1 and FABP2 levels are elevated in children and adolescents with T1DM and could represent a link between diabetic nephropathy and subclinical atherosclerosis.

Biomarkers of Intestinal Injury in Colic

Biomarkers are typically proteins, enzymes, or other molecular changes that are elevated or decreased in body fluids during the course of inflammation or disease. Biomarkers pose an extremely attractive tool for establishing diagnoses and prognoses of equine gastrointestinal colic, one of the most prevalent causes of morbidity and mortality in horses. This topic has received increasing attention because early diagnosis of some forms of severe colic, such as intestinal ischemia, would create opportunities for rapid interventions that would likely improve case outcomes. This review explores biomarkers currently used in equine medicine for colic, including acute phase proteins, proinflammatory cytokines, markers of endotoxemia, and tissue injury metabolites. To date, no single biomarker has been identified that is perfectly sensitive and specific for intestinal ischemia; however, L-lactate has been proven to be a very functional and highly utilized diagnostic tool. However, further exploration of other biomarkers discussed in this review may provide the key to accelerated identification, intervention, and better outcomes for horses suffering from severe colic.

A multicentric prospective observational study of diagnosis and prognosis features in ICU mesenteric ischemia: the DIAGOMI study

BACKGROUND

Non-occlusive mesenteric ischemia (NOMI) is a challenging diagnosis and is associated with extremely high mortality in critically ill patients, particularly due to delayed diagnosis and when complicated by intestinal necrosis. Plasma citrulline and intestinal-fatty acid binding protein (I-FABP) have been proposed as potential biomarkers, but have never been studied prospectively in this setting. We aimed to investigate diagnostic features, the accuracy of plasma citrulline and I-FABP to diagnose NOMI and intestinal necrosis as well as prognosis.

METHODS

We conducted a prospective observational study in 3 tertiary ICU centers in consecutive patients with NOMI suspicion defined by at least two inclusion criteria among: new-onset or worsening circulatory failure, gastrointestinal dysfunction, biological signs and CT-scan signs of mesenteric ischemia. Diagnosis features and outcomes were compared according to NOMI, intestinal necrosis or ruled out diagnosis using stringent classification criteria.

RESULTS

Diagnosis of NOMI was suspected in 61 patients and confirmed for 33 patients, with intestinal necrosis occurring in 27 patients. Clinical digestive signs, routine laboratory results and CT signs of mesenteric ischemia did not discriminate intestinal necrosis from ischemia without necrosis. Plasma I-FABP was significantly increased in presence of intestinal necrosis (AUC 0.83 [0.70-0.96]). A threshold of 3114 pg/mL showed a sensitivity of 70% [50-86], specificity of 85% [55-98], a negative predictive value of 58% [36-93] and a positive predictive value 90% [67-96] for intestinal necrosis diagnosis. When intestinal necrosis was present, surgical resection was significantly associated with ICU survival (38.5%), whereas no patient survived without necrosis resection (HR = 0.31 [0.12-0.75], p = 0.01).

CONCLUSION

In critically ill patients with NOMI, intestinal necrosis was associated with extremely high mortality, and increased survival when necrosis resection was performed. Elevated plasma I-FABP was associated with the diagnosis of intestinal necrosis. Further studies are needed to investigate plasma I-FABP and citrulline performance in less severe forms of NOMI.

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.

l-lactate kinetics after abdominal aortic surgery and intestinal ischemia - An observational cohort study

BACKGROUND

Postoperative intestinal ischemia is a severe complication in abdominal aortic surgery. Early diagnosis is needed for adequate and timely treatment. We studied the postoperative kinetics of l-lactate in vascular patients to assess its value as a marker for early postoperative intestinal ischemia detection.

MATERIAL AND METHODS

We performed a prospective non-randomized single-center observational cohort study in eighty elective patients, fifty operated on for abdominal aortic aneurysm (AAA) and thirty for aortoiliac occlusive disease (AIOD). Serum l-lactate was measured preoperatively, intraoperatively, and postoperatively at defined timepoints up to postoperative day 7. Intestinal ischemia was detected using MRI enterocolography. We have used univariate logistic regression and receiver operating characteristics curves for the evaluation of marker accuracy.

RESULTS

We recorded 6 cases of postoperative intestinal ischemia (7.5%), five non-transmural and one transmural. Two patients died because of this complication (mortality 33%). The comparison of AAA and AIOD cohorts showed a significant difference in l-lactate levels at one intraoperative timepoint, which was attributable to procedure differences. The only preoperative factor associated with higher l-lactate levels at some timepoints was chronic kidney disease. Patients suffering postoperative intestinal ischemia had elevated serum l-lactate levels at multiple timepoints. The most accurate timepoint for diagnosis was 24 h after the declamping of the vascular reconstruction (DC24H), the second was 10 min after declamping. Sensitivity, specificity, positive and negative predictive values at timepoint DC24H were 100%, 82%, 32%, and 100%, respectively.

CONCLUSION

Serum l-lactate levels might help in the early detection of postoperative intestinal ischemia after aortic surgery if proper timepoints are used. Cutoff values need to be established in large-scale prospective studies.

Acute Mesenteric Ischemia in COVID-19 Patients

Acute mesenteric ischemia is a rare but extremely severe complication of SARS-CoV-2 infection. The present review aims to document the clinical, laboratory, and imaging findings, management, and outcomes of acute intestinal ischemia in COVID-19 patients. A comprehensive search was performed on PubMed and Web of Science with the terms "COVID-19" and "bowel ischemia" OR "intestinal ischemia" OR "mesenteric ischemia" OR "mesenteric thrombosis". After duplication removal, a total of 36 articles were included, reporting data on a total of 89 patients, 63 being hospitalized at the moment of onset. Elevated D-dimers, leukocytosis, and C reactive protein (CRP) were present in most reported cases, and a contrast-enhanced CT exam confirms the vascular thromboembolism and offers important information about the bowel viability. There are distinct features of bowel ischemia in non-hospitalized vs. hospitalized COVID-19 patients, suggesting different pathological pathways. In ICU patients, the most frequently affected was the large bowel alone (56%) or in association with the small bowel (24%), with microvascular thrombosis. Surgery was necessary in 95.4% of cases. In the non-hospitalized group, the small bowel was involved in 80%, with splanchnic veins or arteries thromboembolism, and a favorable response to conservative anticoagulant therapy was reported in 38.4%. Mortality was 54.4% in the hospitalized group and 21.7% in the non-hospitalized group (p < 0.0001). Age over 60 years (p = 0.043) and the need for surgery (p = 0.019) were associated with the worst outcome. Understanding the mechanisms involved and risk factors may help adjust the thromboprophylaxis and fluid management in COVID-19 patients.

Association between enterocyte injury and fluid balance in patients with septic shock: a post hoc exploratory analysis of a prospective observational study

Background

The required fluid volume differs among patients with septic shock. Enterocyte injury caused by shock may increase the need for fluid by triggering a systematic inflammatory response or an ischemia-reperfusion injury in the presence of intestinal ischemia/necrosis. This study aimed to evaluate the association between enterocyte injury and positive fluid balance in patients with septic shock.

Methods

This study was a post hoc exploratory analysis of a prospective observational study that assessed the association between serum intestinal fatty acid-binding protein, a biomarker of enterocyte injury, and mortality in patients with septic shock. Intestinal fatty acid-binding protein levels were recorded on intensive care unit admission, and fluid balance was monitored from intensive care unit admission to Day 7. The association between intestinal fatty acid-binding protein levels at admission and the infusion balance during the early period after intensive care unit admission was evaluated. Multiple linear regression analysis, with adjustments for severity score and renal function, was performed.

Results

Overall, data of 57 patients were analyzed. Logarithmically transformed intestinal fatty acid-binding protein levels were significantly associated with cumulative fluid balance per body weight at 24 and 72 h post-intensive care unit admission both before (Pearson’s r = 0.490 [95% confidence interval: 0.263–0.666]; P < 0.001 and r = 0.479 [95% confidence interval: 0.240–0.664]; P < 0.001, respectively) and after (estimate, 14.4 [95% confidence interval: 4.1–24.7]; P = 0.007 and estimate, 26.9 [95% confidence interval: 11.0–42.7]; P = 0.001, respectively) adjusting for severity score and renal function.

Conclusions

Enterocyte injury was significantly associated with cumulative fluid balance at 24 and 72 h post-intensive care unit admission. Enterocyte injury in patients with septic shock may be related to excessive fluid accumulation during the early period after intensive care unit admission.

Non-occlusive mesenteric ischemia: Diagnostic challenges and perspectives in the era of artificial intelligence

Acute mesenteric ischemia (AMI) is a severe condition associated with poor prognosis, ultimately leading to death due to multiorgan failure. Several mechanisms may lead to AMI, and non-occlusive mesenteric ischemia (NOMI) represents a particular form of AMI. NOMI is prevalent in intensive care units in critically ill patients. In NOMI management, promptness and accuracy of diagnosis are paramount to achieve decisive treatment, but the last decades have been marked by failure to improve NOMI prognosis, due to lack of tools to detect this condition. While real-life diagnostic management relies on a combination of physical examination, several biomarkers, imaging, and endoscopy to detect the possibility of several grades of NOMI, research studies only focus on a few elements at a time. In the era of artificial intelligence (AI), which can aggregate thousands of variables in complex longitudinal models, the prospect of achieving accurate diagnosis through machine-learning-based algorithms may be sought. In the following work, we bring you a state-of-the-art literature review regarding NOMI, its presentation, its mechanics, and the pitfalls of routine work-up diagnostic exams including biomarkers, imaging, and endoscopy, we raise the perspectives of new biomarker exams, and finally we discuss what AI may add to the field, after summarizing what this technique encompasses.

Many faces of acute bowel ischemia: overview of radiologic staging

Acute bowel ischemia (ABI) can be life threatening with high mortality rate. In spite of the advances made in diagnosis and treatment of ABI, no significant change has occurred in the mortality over the past decade. ABI is potentially reversible with prompt diagnosis. The radiologist plays a central role in the initial diagnosis and preventing progression to irreversible intestinal ischemic injury or bowel necrosis. The most single imaging findings described in the literature are either non-specific or only present in the late stages of ABI, urging the use of a constellation of features to reach a more confident diagnosis. While ABI has been traditionally categorized based on the etiology with a wide spectrum of imaging findings overlapped with each other, the final decision for patient's management is usually made on the stage of the ABI with respect to the underlying pathophysiology. In this review, we first discuss the pathologic stages of ischemia and then summarize the various imaging signs and causes of ABI. We also emphasize on the correlation of imaging findings and pathological staging of the disease. Finally, a management approach is proposed using combined clinical and radiological findings to determine whether the patient may benefit from surgery or not.

Colonic perforation following major burns: Experience from a burns center and a systematic review

BACKGROUND

Major burns complicated by stress ulceration and perforation of the stomach or duodenum is a recognized clinical phenomenon. Colonic perforation in burns patients is not common, and the overall incidence, diagnosis, intervention undertaken and mortality is incompletely described in the literature.

METHOD

We performed a systematic review of the literature on severe burns resulting in colonic perforation during the initial admission period. Relevant studies from January 1975 to June 2020 were retrieved from MEDLINE and EMBASE databases. Patient demographics, co-morbidities, total body surface area (TBSA) and anatomical region of burn, site of colonic perforation and management, nutrition, sepsis and microbiology, length of stay and overall outcome were extracted. We present a case series of five burns patients who had colonic perforations in our Specialist Burns Center.

RESULTS

We identified 54 studies, of which nine (two case series and seven case reports) met the inclusion criteria. Colonic perforation following burns was most common in middle-aged male patients with a proportion of patients having a history of mental health issues. In most cases, the TBSA associated with a colonic perforation was ≥30% (11/16 patients, 69%). Perforations mainly affected the right side of the colon (12/16 patients, 75%), usually occurring after the second week of admission (13/16 patients, 81%). Right-sided colonic perforations were associated with an increased mortality rate compared to left-sided perforations (42% vs 25%).

CONCLUSIONS

The current literature is mainly limited to case series and case reports and confirms that colonic perforations in burns patients are rare. Colonic perforations are related to the systemic effect of burn injuries including sepsis and gastrointestinal stasis. We have identified patients who are at higher risk of developing colonic perforations and have described the common findings in these patients. Through greater awareness early diagnosis and prompt intervention may be achieved to improve outcomes and reduce associated morbidity and mortality.

When is the right time to take an emergency surgery decision in Mechanical Intestinal Obstruction?

BACKGROUND

/Objective: Ischemia is a leading cause of morbidity in Mechanical Intestinal Obstruction (MIO) in which the timing of decisions of whether to proceed to surgical or conservative treatment is critical in emergency departments (ED). While advanced technological options are available, patients may be negatively affected by the application of contrast agents or radiation. The use of ultrasound is limited because of the air in the intestines does not allow a good field of vision. While biomarkers can be considered as a good alternative option at this point. In the present study we examine the effect of hemogram and blood gas parameters on early surgical decision-making in MIO patients.

METHOD

Involved in this observational prospective study were 264 patients diagnosed with MIO who presented to the Department of Emergency Medicine, Ataturk Research and Training Hospital, Katip Celebi University between February 2018 and February 2019. Contrast-enhanced tomography (CECT) and laboratory results of the patients were recorded. Pathology reports of the patients who underwent surgery were collected. Laboratory data were analyzed by comparing CECT and pathology reports.

RESULTS

In a ROC analysis of the laboratory values of the patients who were diagnosed with ileus, the sensitivity was calculated as 80% and the specificity was 57.7 in values above WBC>10.75 (10⁹/L), 96.6%, and the specificity was 31.1% in N/L > 2.9. For intestinal ischemia, the cut-off values were WBC> 12.6 and N/L > 3.2, Lactate >2.8 mmol/L and B.E < -3.6 mmol/L.

CONCLUSION

Diagnoses of ileus are based on the results examinations and imaging methods. More data are needed to support decisions on the timing of surgery in ED. WBC, N/L, Lactate and Base Excess indicate an ischemic segment. When the parameters are evaluated together, they strongly support early surgical decision-making regarding the treatment of intestinal ischemia.

Acute Mesenteric Infarction: The Chameleon of Acute Abdomen Evaluating the Quality of the Diagnostic Parameters in Acute Mesenteric Ischemia

INTRODUCTION/OBJECTIVE

Acute mesenteric ischemia (AMI) is difficult to diagnose. Since the established parameters have low sensitivity and specificity, the aim of this study is to analyze the diagnostic quality of the established parameters of AMI.

METHODS

All patients that underwent emergency surgery due to suspected diagnosis of mesenteric ischemia at the University Medical Center Hamburg-Eppendorf between 2008 and 2014 were evaluated. Overall, 275 patients were enrolled and pre-, intra- and postoperative data were evaluated.

RESULTS

In 200 patients, a mesenteric ischemia was confirmed intraoperatively, and 75 patients had no ischemia. Comparing these groups, the rate of patients with pH < 7.2 (25 vs. 12%; p = 0.021) and elevated mean CRP level (175 ± 117 mg/L vs. 139 ± 104 mg/L; p = 0.019) was significantly higher in ischemic patients. There was no significant difference in the level of preoperative lactate. Concerning abdominal CT scan, a sensitivity and specificity of 61 and 68%, respectively, was found.

CONCLUSION

New diagnostic parameters are needed. So far, explorative laparotomy is the only reliable diagnostic method to detect mesenteric infarction.

[Is acute mesenteric ischemia incurable situation? The current state of the problem]

Mortality rates in acute mesenteric ischemia remain at an extremely high level for many decades. Early diagnosis and selection of the optimal method of revascularization are among the ways to optimize tactics. The diagnostic study of choice is CT angiography. Its active and systemic use can help to detect ischemia at the reversible stage. The article examines in detail the indications for the application of this diagnostic study. The question of preference for the revascularization method remains debatable. The arguments of proponents of open and endovascular interventions on mesenteric vessels are presented. Other, still unresolved tactical issues are also considered, such as indications for re-operations and application of the principles of damage control tactics.

Hydrogen-rich saline protects intestinal epithelial tight junction barrier in rats with intestinal ischemia-reperfusion injury by inhibiting endoplasmic reticulum stress-induced apoptosis pathway

AIM

To investigate the effects of hydrogen-rich saline (HRS) on intestinal epithelial tight junction (TJ) barrier in rats with intestinal ischemia-reperfusion injury (IIRI).

MATERIALS AND METHODS

Thirty-two healthy male Sprague-Dawley (SD) rats were randomly divided into four groups (n = 8 each): Sham group, I/R group, HRS group and 4-PBA group. After 45 min of ischemia and 6 h of reperfusion, the rats were sacrificed to collect serum and ileum for detection. Hematoxylin and eosin (H&E) staining was used to observe the morphology of small intestine. The serum expression levels of intestinal fatty acid binding protein (IFABP), tumor necrosis factor-α (TNF-α), and interleukin-1β (IL-1β) were determined by enzyme linked immunosorbent assay (ELISA). Imunohistochemistry, immunofluorescence and Western blot were used to detect key proteins in intestinal epithelial TJs, ERS, and ERS-induced apoptosis, including occludin, zonula occludens-1 (ZO-1), glucose-regulated protein 78 (GRP78), X-box binding protein-1 (XBP1), C/EBP-homologous protein (CHOP) and caspase-3. Data was presented as mean ± SEM and compared using one-way ANOVA. A p-value <0.05 was considered significant.

RESULTS

Compared with rats in the I/R group, the Chiu score of ileum damage in the HRS group and 4-PBA group were lower. The levels of serum IFABP, TNF-α, and IL-1β were statistically significant among the groups. Increased expression of TJ proteins occludin and ZO-1 by reducing various parameters of ERS and ERS-induced apoptosis evidenced by down-regulation of the protein levels of GRP78, XBP1, CHOP and caspase-3 were shown in the HRS and 4-PBA groups.

CONCLUSION

HRS had potential protective effects on intestinal barrier in IIRI rats. This study suggested that inhibition of excessive ERS and ERS-induced apoptosis by HRS may reduce intestinal epithelial cells damage and maintain the integrity of intestinal epithelial TJ barrier in rats with IIRI.

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.

Comparison of diagnostic accuracy for nonocclusive mesenteric ischemia in models with biomarkers including intestinal fatty acid-binding protein in addition to clinical findings

BACKGROUND

Nonocclusive mesenteric ischemia (NOMI) is an acute and life-threatening gastrointestinal disorder, requiring rapid therapeutic intervention for ischemic bowel. However, its rapid detection remains challenging. This retrospective, observational study was aimed at comparing the diagnostic accuracy for NOMI in models of biomarkers, including intestinal fatty acid-binding protein (I-FABP), and clinical findings.

METHODS

All consecutive patients who presented to the emergency department of the study hospital with suspected NOMI were prospectively enrolled. Receiver operating characteristic analysis compared the diagnostic accuracy of I-FABP with traditional biomarkers (white blood cell count, C-reactive protein, lactate, creatine kinase, and D-dimer) alone and in combination with the baseline model established from clinical findings.

RESULTS

Of 96 patients with suspected NOMI, 25 (26.0%) were clinically diagnosed with NOMI. In-hospital mortality was higher in patients with NOMI than those with other conditions (56.0% vs. 4.2%, p < 0.001). Receiver operating characteristic analyses revealed that the I-FABP model had the highest area under the curve (0.805) in the diagnosis of NOMI, compared with other biomarkers. The diagnostic model of clinical findings including age, cardiovascular disease history, undergoing hemodialysis, hypotension, and consciousness disturbance in combination with I-FABP showed the best discrimination (area under the curve, 0.883), compared with other biomarkers. The bootstrap optimism estimate showed the lowest discrimination among the other models with other biomarkers (0.006).

CONCLUSION

The usefulness of I-FABP for final diagnosis of NOMI in patients with clinically suspected NOMI at the emergency department was internally validated. Further external validation study is warranted.

LEVEL OF EVIDENCE

Diagnostic test, level III.

The Role of Gastrointestinal-Related Fatty Acid-Binding Proteins as Biomarkers in Gastrointestinal Diseases

The fatty acid-binding proteins play a major role in intracellular transportation of long-chain fatty acids. Nine fatty acid-binding proteins have been identified, with each having individual tissue-specific functions in addition to regulation of fatty acids. This review focuses on the three fatty acid-binding proteins found in the gastrointestinal tract and discusses their role as diagnostic or disease monitoring markers in neonatal necrotizing enterocolitis, acute mesenteric ischemia, celiac disease, and inflammatory bowel disease. Of these three fatty acid-binding proteins, intestinal fatty acid-binding protein is of the most interest due to its exclusive expression in the gastrointestinal tract. The elevation of intestinal fatty acid-binding protein in blood and urine reflects enterocyte damage, regardless of the underlying cause. The short half-life of intestinal fatty acid-binding protein also means it is a relatively sensitive marker. In contrast, there is currently less evidence to support liver fatty acid-binding protein and ileal bile acid-binding protein as sensitive biomarkers in these conditions. More extensive studies with specific endpoints are required to validate the roles of these fatty acid-binding proteins in gastrointestinal diseases.

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.

FABP1 and FABP2 as markers of diabetic nephropathy

Background: Diabetes mellitus is the leading cause of diabetic nephropathy and a major public health issue worldwide. Approximately 20-30% of patients with type 2 diabetes mellitus (T2DM) have renal impairment. Fatty acid-binding protein 1 (FABP1) is expressed in renal proximal tubule cells and released into urine in response to hypoxia caused by decreased peritubular capillary blood flow, and FABP2 is responsible for the transport of free fatty acids in the intestinal endothelium cells. There is increasing evidence that FABP1 and FABP 2 play a role in the development and progression of chronic kidney disease. The aim of this study was to investigate the relation of circulating FABP1 and FABP2 levels to nephropathy in patients with T2DM. Methods: For this study, 268 subjects with T2DM who were enrolled in a disease management program were stratified according to urinary microalbumin and serum creatinine measurements. The plasma FABP1 and FABP2 concentrations were examined by enzyme-linked immunosorbent assay. Demographic and potential metabolic confounding factors were analyzed with logistic regression to calculate the effects of FABP1 and FABP2 levels on diabetic nephropathy. Results: The FABP1 and FABP2 levels increased in parallel with the advancement of diabetic nephropathy. Increasing concentrations of FABP1 and FABP2 were independently and significantly associated with diabetic nephropathy. Multiple logistic regression analysis revealed FABP1 and FABP2 as an independent association factor for diabetic nephropathy, even after full adjustment of known biomarkers. Furthermore, receiver operating characteristic curve analysis showed that a FABP1 level of >33.8 ng/mL and a FABP2 level of >2.8 ng/mL were associated with diabetic nephropathy. Conclusion: Our results suggest that FABP1 and FABP2 may be novel biomarkers of diabetic nephropathy.

ROLE OF LABORATORY METHODS IN INTEGRATED DIAGNOSTICS OF ACUTE MESENTERIAL ISCHEMIA

The aim of the review: to present literature data on the role of laboratory methods in the complex diagnosis of acute mesenteric ischemia. The main provisions. To search for scientific publications, we used the PubMed database, the RSCI, the Google Scholar search engine, as well as cited references. Articles relevant to the purpose of the review were selected for the period from 1999 to 2019 in the following terms: “acute mesenteric ischemia”, “pathogenesis”, “diagnosis”, “biomarkers”. Inclusion criteria were limited to acute arterial mesenteric ischemia. Acute mesenteric ischemia is an emergency condition caused by a sudden violation of the blood flow through the mesenteric vessels, which rapidly progresses to a heart attack of the intestinal wall and is accompanied by high mortality. Four main mechanisms of OMI are distinguished: embolism from the left parts of the heart or aorta, thrombosis of arteries or veins of the intestine, non-occlusive acute mesenteric ischemia (NOMI), due to vascular spasm. In this case, destructive disorders occur in the intestinal wall, starting from the mucous membrane to the serous, which leads to bacterial translocation and the development of a systemic inflammatory response syndrome. Early bowel revascularization is a key factor in reducing complications and mortality associated with it. However, in the initial stages of the disease has no specific signs, which complicate its diagnosis. The only way to detect mesenteric blood flow disorders is MSCT with angiography, and with non-occlusive lesions, mesenteric angiography, which in normal clinical practice is not always possible. Conclusion. It can be assumed that the use of laboratory methods will expand the range of diagnostic measures and will make it possible to conduct timely treatment aimed at restoring the mesenteric blood flow and improve the prognosis in patients with acute mesenteric ischemia.

Screening and combining serum biomarkers to improve their diagnostic performance in the detection of intestinal barrier dysfunction in patients after major abdominal surgery

Background

The aim of this prospective study was to screen and combine effective biomarkers to improve their diagnostic performance in detecting intestinal barrier dysfunction in patients after major abdominal surgery.

Methods

Patients undergoing major abdominal surgery were enrolled after signing informed consent in this study. The serum concentrations of α-GST, DAO, D-lactate, citrulline and I-FABP were detected 24 hours before and after surgery. The diagnostic performance of five biomarkers on intestinal barrier dysfunction was assessed using logistic regression models and receiver operating characteristic (ROC) curve analyses.

Results

Thirty-nine patients with major abdominal surgery were enrolled in and successfully completed this study. ROC analysis revealed that the sensitivities of D-lactate, citrulline and I-FABP were very high (0.91, 0.91 and 1.00, respectively), but the specificities of these biomarkers were less than 0.70. The sensitivity of DAO was very low [0.25; 95% confidence interval (CI), 0.05-0.57], but its specificity was high (0.92; 95% CI, 0.75-0.99). The accuracies of D-lactate and I-FABP were very high, and the areas under the curves (AUCs) of the biomarkers were 0.84 (95% CI, 0.68-0.93) and 0.81 (95% CI, 0.65-0.92), respectively. Different combinations of five biomarkers were also analysed. The sensitivity, specificity and AUC values of the combination of I-FABP, citrulline and D-lactate were 1.00, 0.74 and 0.89, respectively. These results were similar to those derived from the combination of α-GST, DAO, D-lactate, citrulline and I-FABP (P=1.000).

Conclusions

The combination of serum D-lactic acid, citrulline and I-FABP greatly improved the diagnostic performance for identifying intestinal barrier dysfunction in patients after major abdominal surgery.

Association between endotoxemia and enterocyte injury and clinical course in patients with gram-positive septic shock: A posthoc analysis of a prospective observational study

Endotoxemia often occurs in patients with gram-positive infections. The possible mechanism is thought to be bacterial translocation after enterocyte hypoperfusion injury. However, the association between endotoxemia and enterocyte injury among patients with gram-positive septic shock has never been assessed. The aim of this study was to evaluate the association between endotoxemia and enterocyte injury in gram-positive septic shock patients and to evaluate the association among endotoxemia, subsequent clinical course, and other related factors.This was a posthoc analysis of a prospective observational study that evaluated the capability of intestinal fatty acid-binding protein (I-FABP), an indicator of enterocyte injury, to predict mortality. Among 57 patients in septic shock, those whose causative microorganisms were gram positive were included. The correlation between endotoxin activity (EA), which indicates endotoxemia, and I-FABP levels upon admission to the intensive care unit (ICU), the clinical course, and other related factors were evaluated.A total of 21 patients were examined. One-third of the patients presented with high EA levels at the time of ICU admission. However, there was no significant correlation between EA and I-FABP levels (Spearman ρ = 0.002, P = .993). Additionally, high EA levels were not associated with abdominal complications after ICU admission or mortality. Similarly, high EA levels were not associated with severity scores, inotropic scores, or lactate levels upon ICU admission, which were previously reported to be factors related to high EA levels.In this posthoc analysis, no correlation was observed between endotoxemia and enterocyte injury among patients in gram-positive septic shock. Additionally, high EA levels were not associated with the clinical course and reported factors related to endotoxemia. Although our results need to be validated in a large prospective cohort study, hypoperfusion enterocyte injury might not be a cause of endotoxemia in these patients. Thus, if there is no correlation between EA and I-FABP levels, other mechanisms that induce high EA levels among patients with gram-positive septic shock should be elucidated.

Surgical considerations for neonates with necrotizing enterocolitis

Necrotizing enterocolitis (NEC) is a potentially devastating condition that preferentially affects premature and low birth weight infants, with approximately half requiring acute surgical intervention. Surgical consult should be considered early on, and deterioration despite maximal medical therapy or the finding of pneumoperitoneum are the strongest indications for emergent surgical intervention. There is no clear consensus on the optimal surgical approach between peritoneal drainage and laparotomy; the best course of action likely depends on the infant's comorbidities, hemodynamic status, size, disease involvement, and available resources. Patients who develop surgical NEC are at a significant risk for morbidity and mortality, with long-term complications including short bowel syndrome, growth failure, and neurodevelopmental impairment. Further research into strategies that optimize outcomes following surgery for NEC in the neonatal intensive care unit and long-term are paramount.

Association Between Macroscopic Tongue Ischemia and Enterocyte Injury and Poor Outcome in Patients With Septic Shock: A Preliminary Observational Study

A correlation between sublingual and intestinal mucosa microcirculation, and ischemic necrosis of the tongue as a sign of poor prognosis has been reported. However, an association between tongue ischemia and intestinal health and subsequent outcome has never been studied. This preliminary prospective observational study evaluated the association between macroscopic tongue ischemia and enterocyte injury and poor outcome in patients with septic shock. In this study, 57 adults with septic shock on mechanical ventilators were enrolled. Macroscopic tongue ischemia upon intensive care unit (ICU) admission was assessed by two independent intensivists. We used intestinal fatty-acid binding protein (I-FABP) as a biomarker of enterocyte injury and evaluated the association with tongue ischemia. Demographic variables, risk factor data, and 28-day mortality information were also collected. Compared with patients with normal tongues (n = 45), those with ischemic tongues (n = 12) had a significantly higher Acute Physiology and Chronic Health Evaluation II score (29.0 [25.0-34.0] vs. 36.5 [30.5-44.5], P = 0.017), lactate level (2.8 [2.0-5.0] vs. 9.3 [4.5-10.6], P = 0.002), and I-FABP level (1.9 [0.8-4.0] vs. 54.4 [19.5-159.3], P < 0.001) and the all-cause 28-day mortality was significantly higher (7% vs. 83%, P < 0.001). In conclusion, macroscopic tongue ischemia at ICU admission was associated with enterocyte injury and poor outcome in patients with septic shock. Although there is a disadvantage in that assessment of the tongue was subjective, tongue ischemia could be used to gauge the severity of intestinal injury and to estimate poor outcome in the clinical setting.

Biochemical markers of acute intestinal ischemia: possibilities and limitations

Acute intestinal ischemia is a relative rare abdominal emergency, associated with considerably high morbidity and mortality rates. Although the conventional diagnostic approach to acute intestinal ischemia entails a preliminary evaluation of signs and symptoms, followed by radiological and laboratory investigations, a definitive diagnosis is can usually be made after laparotomy, which still remains the gold standard diagnostic (and therapeutic) procedure. Several potential laboratory biomarkers have been investigated over the past decades, but none of these seems to reach a suitable diagnostic accuracy for an early and reliable diagnosis of intestinal ischemia. The aim of this narrative review is to provide an overview on traditional laboratory tests for diagnosing acute intestinal ischemia (i.e., complete blood count, D-dimer, blood gas analysis, total lactic acid, C-reactive protein and procalcitonin), and summarize current evidence regarding some emerging and potentially useful biomarkers such as D-lactate, intestinal fatty acid-binding protein (I-FABP), ischemia modified albumin (IMA), α-glutathione S-transferase (α-GST), interleukin-6 (IL-6), citrulline and smooth muscle protein of 22 kDa (SM22). Among the various tests, D-lactate, IMA and I-FABP are perhaps the most promising, since they are characterized by optimal sensitivity and relatively good specificity, early kinetics, and can be measured with assays suited for a rapid diagnosis.

Acute mesenteric ischaemia: a pictorial review

Abstract

Acute mesenteric ischaemia (AMI) is an uncommon cause of acute hospital admission with high mortality rates (50–90%) that requires early diagnosis and treatment. With the increase in average life expectancy, AMI represents one of the most threatening abdominal conditions in elderly patients. Untreated, AMI will cause mesenteric infarction, intestinal necrosis, an overwhelming inflammatory response and death. Early intervention can reverse this process leading to a full recovery, but the diagnosis of AMI is difficult. The failure to recognise AMI before intestinal necrosis has developed is responsible for the high mortality of the disease. Unfortunately, common CT findings in bowel ischaemia are not specific. Therefore, it is often a combination of nonspecific clinical, laboratory and radiological findings that helps most in the correct interpretation of CT findings. The purpose of this article is to provide an overview of the anatomy, physiology of mesenteric perfusion and discussions of causes, pathogenesis and CT findings in various types of acute bowel ischaemia. Familiarity with various imaging features of mesenteric injury is essential to make a timely diagnosis that will lead to improved patient outcomes.

Teaching Points

• AMI is a potentially life-threatening disorder whose prognosis depends on early recognition, accurate diagnosis and timely intervention.

• Arterial inflow occlusion due to thrombosis or embolisation is the most common cause of AMI.

• Four aetiological types of AMI have been associated with different characteristics and risk factors (EAMI, TAMI, VAMI and NOMI).

• Physical examination and laboratory findings are not sensitive or specific for diagnosing AMI; therefore, MDCT is still the first-line imaging method in suspected AMI.

• Although a number of scoring systems for prognosis have been proposed, these have not been validated in large-scale studies.