Is D-dimer a predictor of strangulated intestinal hernia?

The Efficiency of Serum Biomarkers in Predicting the Clinical Outcome of Patients with Mesenteric Ischemia during Follow-Up: A Systematic Review

The initial clinical manifestation of acute mesenteric ischemia poses a diagnostic challenge, often leading to delays in identification and subsequent surgical intervention, contributing to adverse outcomes. Serum biomarkers, offering insights into the underlying pathophysiology, hold promise as prognostic indicators for acute mesenteric ischemia. This systematic review comprehensively explores the role of blood biomarkers in predicting clinical outcomes during follow-up for patients with mesenteric ischemia. A thorough literature search across the PubMed, Cochrane Library, and EMBASE databases yielded 33 relevant publications investigating the efficacy of serum biomarkers in predicting outcomes for mesenteric ischemia. Numerous studies underscore the utility of blood biomarkers in swiftly and accurately differentiating between causes of mesenteric ischemia, facilitating a prompt diagnosis. Elevated levels of specific biomarkers, particularly D-dimers, consistently correlate with heightened mortality risk and poorer clinical outcomes. While certain serum indicators exhibit substantial potential in associating with mesenteric ischemia, further research through rigorous human trials is imperative to enhance their consistent predictive ability during the follow-up period. This study underscores the diagnostic and prognostic significance of specific biomarkers for mesenteric ischemia, emphasizing the necessity for standardized procedures in future investigations.

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.

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.

Haematological inflammatory markers for indicating ischemic bowel in patients with incarcerated abdominal wall hernias

PURPOSE

To reveal the clinical significance of preoperative haematological inflammatory markers in the diagnosis of abdominal wall hernias with strangulation.

METHODS

The data of 200 patients who underwent surgery for incarcerated hernia were retrospectively analysed. The patients were grouped into three groups; Group 1; only surgical reduction and hernia repair, Group 2; small bowel resection and Group 3; omentum resection. Age, gender, hernia type, the presence of radiological bowel obstruction and preoperative complete blood count data were obtained. Neutrophil-leukocyte ratio (NLR), lymphocyte-monocyte ratio (LMR), platelet-lymphocyte ratio (PLR), haematological inflammatory index (HII) and systemic immune-inflammation index (SII) values were calculated.

RESULTS

The study was consisted of; Group 1: 119 patients (59.5%), Group 2: 46 patients (23%) and Group 3: 35 patients (17.5%). Advanced age (p = 0.001), female gender (p = 0.036), incisional hernias (p =  < 0.001) and the presence of bowel obstruction (p =  < 0.001) were found to be statistically significant in terms of strangulation. NLR, PLR and SII values were significantly higher in Group 2 compared to Group 1, and PLR values were significantly higher in Group 2 compared with Group 3 (p < 0.05).

CONCLUSION

The preoperative elevated NLR, PLR and SII values may indicate strangulation and possible intestinal resection, in incarcerated abdominal wall hernias.

Algorithm for management of an incarcerated inguinal hernia in the emergency settings with manual reduction. Taxis, the technique and its safety

BACKGROUND

An acute inguinal hernia remains a common emergency surgical condition worldwide. While emergency surgery has a major role to play in treatment of acute hernias, not all patients are fit for emergency surgery, nor are facilities for such surgery always available. Taxis is the manual reduction of incarcerated tissues from the hernia sack to its natural compartment, and can help delay the need for surgery from days to months. The aim of this study was to prepare a safe algorithm for performing manual reduction of incarcerated inguinal hernias in adults.

METHODS

Medline, Scopus, Ovid and Embase were searched for papers related to emergency inguinal hernias and manual reduction. In addition, the British National Formulary and Safe Sedation Practice for Healthcare Procedures: Standards and Guidance were reviewed.

RESULTS

A safe technique of manual reduction of an acute inguinal hernia, called GPS (Gentle, Prepared and Safe) Taxis, is described. It should be performed within 24 h from the onset of a painful irreducible lump in groin, and when concomitant symptoms and signs of bowel strangulation are absent. Conscious sedation guidelines should be followed. The most popular drug combination is of intravenous morphine and short-acting benzodiazepine, both titrated carefully for optimal and safe effect. The dose of drugs must be individualised, and the smallest effective dosage should be used to avoid oversedation. Following successful taxis, the patient should undergo a short period of observation. Urgent surgery can be undertaken during the same admission or up to several weeks later.

CONCLUSIONS

Taxis is a benign/non-invasive method for patients with an acute, non-strangulated inguinal hernias. It likely reduces the risk and complications of anaesthesia and surgery in the emergency settings. GPS Taxis should be considered as first line treatment in the majority of patients presenting with an acute inguinal hernia when existing bowel infarction is unlikely.

The Diagnostic Value of Coagulation Indicators and Inflammatory Markers in Distinguishing Between Strangulated and Simple Intestinal Obstruction

BACKGROUND

Intestinal obstruction with strangulation can be life-threating, and it is critical to make an accurate and timely diagnosis for emergency surgery.

OBJECTIVE

This was aimed to investigate the value of coagulation indicators and inflammatory markers in distinguishing between strangulated and simple intestinal obstruction.

MATERIALS AND METHODS

Fifty-four patients with intestinal obstruction were retrospectively studied. The correlation between coagulation indicators and inflammatory markers with intestinal obstruction was analyzed. Receiver operating characteristic curves were created to assess their ability in discriminative diagnosis.

RESULTS

Levels of fibrinogen (Fib), C-reactive protein (CRP), neutrophil ratio, and D-Dimer were significantly greater, while thrombin time was significantly shorter in strangulated intestinal obstruction compared with simple intestinal obstruction. Furthermore, Fib levels in the necrosis subgroup of strangulated intestinal obstruction were significantly higher than those in the ischemia subgroup and simple intestinal obstruction group. The areas under the receiver operating characteristic curve were 0.58 for white blood cells, 0.78 for CRP, and 0.80 for Fib. Using the optimal cutoff values of Fib (3.71 g/L) and CRP (14.54 mg/L), the sensitivity, specificity, positive predictive value, and negative predictive value in discriminating between strangulated intestinal obstruction and simple intestinal obstruction were 51.43%, 100%, 100%, and 52.78% for Fib, and 56.25%, 94.44%, 94.74%, and 54.84% for CRP, respectively.

CONCLUSIONS

Fib and CRP demonstrate good performance in predicting strangulation and are indicative of intestinal necrosis and ischemia. The combination of this coagulation indicator and inflammatory marker holds potential for better discrimination between strangulated and simple intestinal obstruction.

Predictors of ischemic bowel in patients with incarcerated hernias

PURPOSE

Diagnosing intestinal strangulation in the setting of incarcerated hernias remains challenging. Hyponatremia has been identified as a predictor of necrotizing soft tissue infections and gangrenous cholecystitis. We hypothesized that hyponatremia could predict bowel ischemia in patients with incarcerated hernias.

METHODS

Medical records for 163 patients with incarcerated hernias over a 5-year period were reviewed. Preoperative clinical, laboratory, and radiologic findings and final intraoperative diagnosis were collected.

RESULTS

Thirty-six patients (22.1%) had ischemic bowel requiring resection. Univariate analysis identified multiple significant variables including lower serum sodium (p = 0.002), lower bicarbonate (p = 0.04), elevated glucose (p = 0.0002), elevated white blood cell count (p = 0.001), and skin changes (p = 0.001). In a multivariable model, skin changes were associated with an odds ratio for ischemia of 3.3 (1.3-8.6 p = 0.02). Sodium of less than 135 had an odds ratio for ischemia of 3.9 (1.7-9.1, p = 0.004).

CONCLUSION

Hyponatremia should raise suspicion for underlying strangulated bowel and prompt urgent exploration in patients with incarcerated hernias.

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.

Secondary peritonitis: principles of diagnosis and intervention

Secondary peritonitis accounts for 1% of urgent or emergent hospital admissions and is the second leading cause of sepsis in patients in intensive care units globally. Overall mortality is 6%, but mortality rises to 35% in patients who develop severe sepsis. Despite the dramatic growth in the availability and use of imaging and laboratory tests, the rapid diagnosis and early management of peritonitis remains a challenge for physicians in emergency medicine, surgery, and critical care. In this article, we review the pathophysiology of peritonitis and its potential progression to sepsis, discuss the utility and limitations of the physical examination and laboratory and radiographic tests, and present a paradigm for the management of secondary peritonitis.

2017 update of the WSES guidelines for emergency repair of complicated abdominal wall hernias

Emergency repair of complicated abdominal wall hernias may be associated with worsen outcome and a significant rate of postoperative complications. There is no consensus on management of complicated abdominal hernias. The main matter of debate is about the use of mesh in case of intestinal resection and the type of mesh to be used. Wound infection is the most common complication encountered and represents an immense burden especially in the presence of a mesh. The recurrence rate is an important topic that influences the final outcome. A World Society of Emergency Surgery (WSES) Consensus Conference was held in Bergamo in July 2013 with the aim to define recommendations for emergency repair of abdominal wall hernias in adults. This document represents the executive summary of the consensus conference approved by a WSES expert panel. In 2016, the guidelines have been revised and updated according to the most recent available literature.

Accuracy of using serum D-dimer for diagnosis of acute intestinal ischemia: A meta-analysis

OBJECTIVE

The purpose of this meta-analysis is to comprehensively assess the accuracy of serum D-dimer for the diagnosis of acute intestinal ischemia.

METHODS

Diagnostic studies of D-dimer for accurate diagnosis of acute intestinal ischemia were extracted from 6 databases, and prospective and retrospective studies that provided adequate data on sensitivity and specificity were included here. Sensitivity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were calculated. The overall diagnostic performance of D-dimer was assessed by plotting a summary receiver operating characteristic curve (SROC) and calculating the area under the curve (AUC).

RESULTS

A total of 1300 patients with suspected acute intestinal ischemia from 12 studies met the inclusion criteria. The combined sensitivity, specificity, PLR, NLR, and DOR were 0.94 (95% CI: 0.87-0.97), 0.50 (95% CI: 0.40-0.61), 1.9 (95% CI: 1.5-2.3), 0.12 (95% CI: 0.05-0.26), and 16 (95% CI: 7-39), respectively. The AUC was 0.81 (95% CI: 0.78-0.84).

CONCLUSION

The results of this meta-analysis suggested that plasma D-dimer detection might be a useful means of identifying patients with acute intestinal ischemia of the abdomen.

D-dimer as an early marker of severity in patients with acute superior mesenteric venous thrombosis

No early serum marker of disease severity contributes to the treatment decision-making process of acute superior mesenteric venous thrombosis (ASMVT). This study aims to assess the value of serum D-dimer level in the first 3 days after admission as a severity marker of ASMVT patients. From May 2010 to June 2014, 50 consecutive patients of ASMVT were enrolled in this observational study. The serum D-dimer level was measured on a daily basis during the first 3 days after admission as well as other laboratory-testing parameters, clinical score, and outcome variables recorded during the same period. The maximum and mean D-dimer values were analyzed and compared with other potential markers for prediction of multiple-organ dysfunction syndrome (MODS) and short-bowel syndrome (SBS). The correlation of D-dimer level with other potential severity markers and inflammation parameters were also studied. Both maximum and mean D-dimer level during the first 3 days of admission were significantly higher in patients with several clinical variables such as death within 30 days, bowel resection, sepsis, abdominal compartment syndrome, MODS, and SBS. In addition, serum D-dimer level showed precise prediction for MODS and SBS, greater than L-lactate and intestinal-type fatty acid-binding protein (I-FABP). The D-dimer level was correlated well with L-lactate, I-FABP, and APACHE II score on the first 3 days of admission. Poor correlation of D-dimer level and inflammation parameters, white blood cell count, and C-reactive protein level, was detected. D-dimer level could be an effective, early, and specific serum marker indicating the clinical evolution and outcome of ASMVT.

Diagnostic performance of plasma biomarkers in patients with acute intestinal ischaemia

BACKGROUND

The aim of this study was to evaluate the use of intestinal fatty acid binding protein (I-FABP) and traditional biomarkers in the early diagnosis of acute intestinal ischaemia of different causes.

METHODS

I-FABP, white blood cell (WBC) count, C-reactive protein, base deficit, lactate, lactate dehydrogenase, aspartate aminotransferase, creatine kinase and D-dimer were measured prospectively in consecutive patients suspected of having acute intestinal ischaemia. Biomarker levels were compared in patients with vascular and non-vascular ischaemia.

RESULTS

Two hundred and eight patients with a clinical suspicion of acute intestinal ischaemia were enrolled. Vascular intestinal ischaemia was diagnosed in 24 patients (11·5 per cent), non-vascular ischaemia in 62 (29·8 per cent) and non-ischaemic disease in 122 (58·7 per cent). The levels of most biomarkers (except WBC count and creatine kinase) were significantly higher in the vascular ischaemia group than in the other groups (P < 0·010). However, none of the biomarker levels differed between patients with non-vascular intestinal ischaemia and those with non-ischaemic disease. Receiver operating characteristic (ROC) curve analysis suggested that I-FABP was best at diagnosing vascular intestinal ischaemia (area under the curve 0·88).

CONCLUSION

Serum biomarkers may be useful in the diagnosis of vascular, but not non-vascular, intestinal ischaemia. Among them, I-FABP shows promise for detecting vascular ischaemia.

WSES guidelines for emergency repair of complicated abdominal wall hernias

Emergency repair of complicated abdominal hernias is associated with poor prognosis and a high rate of post-operative complications.A World Society of Emergency Surgery (WSES) Consensus Conference was held in Bergamo in July 2013, during the 2nd Congress of the World Society of Emergency Surgery with the goal of defining recommendations for emergency repair of abdominal wall hernias in adults. This document represents the executive summary of the consensus conference approved by a WSES expert panel.

Histidine decarboxylase is identified as a potential biomarker of intestinal mucosal injury in patients with acute intestinal obstruction

Various biomarkers currently used for the diagnosis of intestinal mucosal injury (IMI) in patients with acute intestinal obstruction have low sensitivity and specificity. In the present study, IMI, as indicated by the impaired expression of tight junction proteins, including zonula occludens-1, occludin and claudin-1, and inflammation were determined in colonic tissues of patients with 45 strangulated intestinal obstruction (STR-IO) and the adjacent "normal" colonic tissues of 35 patients with colon cancers by quantitative real-time polymerase chain reaction (QRT-PCR), Western blotting, immunohistochemistry and histological examination, respectively. Then, two-dimensional fluorescent difference gel electrophoresis coupled with linear trap quadrupole mass spectrometry was used to screen for potential biomarkers of IMI in the serum samples of 10 STR-IO, 10 simple intestinal obstruction (SIM-IO) and 10 normal healthy controls. A total of 35 protein spots were differentially expressed among the serum samples, and six of the proteins were identified as potential biomarkers. Among the six proteins, histidine decarboxylase (HDC) and ceruloplasmin (CP) were elevated significantly in patients with STR-IO, compared with patients with SIM-IO and healthy controls. Thus, HDC and CP were further validated by QRT-PCR, Western blotting, immunohistochemistry and enzyme-linked immunosorbent assay, respectively, in colonic tissues, serum and urine samples. Finally, the receiver operating characteristic curves were used to show the area under the curves of HDC, CP and several established biomarkers, followed by the determination of the appropriate cutoff values and their sensitivities and specificities. It was shown that for serum and urine, HDC levels achieved sensitivities and specificities compatible to or even greater than those of established biomarkers for the diagnosis of IMI in patients with acute intestinal obstruction, although further validation in a larger cohort is required.

Serum markers and intestinal mucosal injury in chronic gastrointestinal ischemia

BACKGROUND

Diagnosing chronic gastrointestinal ischemia (CGI) is a challenging problem in clinical practice. Serum markers for CGI would be of great diagnostic value as a non-invasive test method.

AIMS

This study investigated serum markers in patients with well-defined ischemia. Furthermore, intestinal mucosal injury was also evaluated in CGI patients.

METHODS

Consecutive patients suspected of CGI were prospectively enrolled and underwent a diagnostic work-up consisting of gastrointestinal tonometry and either CT or MR angiography. Blood samples for analysis of intestinal fatty acid-binding protein (I-FABP), D-dimer, lactate dehydrogenase (LDH), leucocyte counts, C-reactive protein (CRP), and L-lactate were drawn before and after a standard meal. Intestinal mucosal injury was assessed with glutamine, citrulline and arginine in blood samples and compared to a sugar absorption test (SAT). Test reproducibility was validated in healthy subjects.

RESULTS

Forty patients and nine healthy subjects were included. Ischemia was diagnosed in 32 patients (80%). I-FABP, leucocyte counts, LDH, CRP, glutamine, citrulline, arginine and SAT levels did not differ between patients with and without ischemia. L-lactate concentration showed a significant elevation in ischemia patients as compared to non-ischemia patients. In ischemia patients, D-dimer levels showed a significant elevation postprandially as compared to D-dimer levels at baseline. However, these ischemia patients did not show intestinal mucosal injury.

CONCLUSIONS

I-FABP, leucocyte counts, LDH and CRP levels are not clinically useful for the diagnosis of CGI. However, postprandial rises in L-lactate and D-dimer serum levels can serve as non-invasive indicators of CGI.

D-dimer in patients with suspected acute mesenteric ischemia

OBJECTIVES

The aims of this study were to assess the diagnostic value of D-dimer in patients with suspected acute mesenteric ischemia (AMI) and to evaluate the correlation between D-dimer levels and the severity of bowel necrosis.

METHODS

A prospective, noninterventional study of 67 patients with clinical suspicion of AMI was performed. Measurement of D-dimer levels was performed using a latex turbidimetric method.

RESULTS

Acute mesenteric ischemia was diagnosed in 23 patients (34.3%) and non-AMI in 44 patients (65.7%). Median D-dimer levels on admission were 6.24 microg fibrinogen equivalent units (FEU)/mL (range, 0.96-53.48 microg FEU/mL) in patients with AMI and 3.45 microg FEU/mL (range, 0.50-44.69 microg FEU/mL) in non-AMI patients (P = .064). D-dimer had poor discriminative value to differentiate the presence from the absence of AMI with an area under the receiver operating characteristic curve of 0.64 (95% confidence interval, 0.50-0.78). A serum D-dimer cutoff value of 1.0 microg FEU/mL had a sensitivity of 96%, a specificity of 18%, a positive likelihood ratio of 1.17, and a negative likelihood ratio of 0.24. Among patients with AMI verified at operation, 8 had resectable bowl necrosis and 9 had unresectable bowel necrosis. There was no difference in serum D-dimer levels between resectable and unresectable bowel necrosis (P = .665).

CONCLUSIONS

Detection of serum D-dimer could not help to differentiate patient with AMI from those with non-AMI. We did not find a correlation between serum D-dimer levels and the severity of AMI. However, measurement of D-dimer levels can be of value for a small decrease in the likelihood of AMI, when the result is low.

Systematic review and pooled estimates for the diagnostic accuracy of serological markers for intestinal ischemia

BACKGROUND

Intestinal ischemia is a potentially catastrophic abdominal emergency that presents a significant diagnostic challenge in the critical care setting. We performed a systematic review of the literature to define the diagnostic accuracy of serological markers of intestinal ischemia.

METHODS

Observational studies on the performance of markers of intestinal ischemia were identified within the MEDLINE and EMBASE electronic databases. All studies from which it was possible to derive true positive, false positive, false negative, and true negative results were included. A random-effects model was used to calculate the pooled estimates of diagnostic accuracy.

RESULTS

A total of 20 articles examining 18 different serological markers were identified that met the inclusion criteria. The global measures of test performance (diagnostic odds ratio and area under the summary receiver operating characteristic curve) for markers investigated in three or more studies were D-lactate (10.75 and 0.86, respectively), glutathione S-transferase (GST; 8.82 and 0.87, respectively), intestinal fatty-acid binding protein (i-FABP; 7.62 and 0.78, respectively), and D-dimer (5.77 and 0.53, respectively).

CONCLUSIONS

The performance of the currently available serological markers is suboptimal for routine clinical use, but novel markers of intestinal ischemia such as D-lactate, GST, and i-FABP may offer improved diagnostic accuracy. The early diagnosis of intestinal ischemia remains a challenge, and further research is required to identify improved serological markers and to demonstrate their clinical utility in the individual patient.

D-dimer as a predictor of the need for laparotomy in patients with unclear non-traumatic acute abdomen. A preliminary study

OBJECTIVE

The acute onset of intense abdominal pain requires rapid evaluation, and since D-dimer level is reported to be useful in the diagnosis of patients with suspected acute superior mesenteric artery occlusion, our aim was to evaluate the value of D-dimer testing in the diagnosis of acute surgical abdomen with no precise diagnosis.

MATERIAL AND METHODS

Between July 2004 and June 2006, 93 patients with acute abdomen who required surgical exploration without precise diagnosis were admitted to this prospective clinical study. After surgery, the patients were divided into two groups: group 1 (n=52), patients who needed immediate laparotomy, and group 2 (n=41), patients without the need for laparotomy. Blood samples were taken to analyse D-dimer, white blood cell count and pH level. P-values of <0.05 were considered statistically significant.

RESULTS

There was a positive correlation between the plasma D-dimer level and leucocyte count. Leucocyte counts > 16,800/mm3 (p < 0.01) and D-dimer levels >4.7 microg FEU/mL were more sensitive (p < 0.001). Sensitivity was 97.6% and specificity 61.5% for D-dimer level, and 82.9% and 42.3%, respectively, for leucocyte count. Metabolic acidosis at admission was the most important factor for mortality (p < 0.001).

CONCLUSIONS

In a patient with acute abdomen without precise diagnosis, a D-dimer level above the cut-off value (4.7 microg fibrinogen equivalent units/mL) may be an indicator with high sensitivity for surgical pathology requiring laparotomy.

Diagnostic accuracy of plasma biomarkers for intestinal ischaemia

OBJECTIVE

Intestinal ischaemia is a life-threatening condition with high mortality, and the lack of accurate and readily available diagnostic methods often results in delay in diagnosis and treatment. The aim of this study was to investigate the accuracy of different plasma biomarkers in diagnosing intestinal ischaemia.

MATERIAL AND METHODS

Prospective inclusion of patients older than 50 years with acute abdomen admitted to hospital in Karlskrona, Sweden, between 2001 and 2003. Venous blood was sampled prior to any surgery and within 24 h from onset of pain. D-lactate, alpha glutathione S-transferase, intestinal fatty acid binding protein, creatine kinase B, isoenzymes of lactate dehydrogenase (LD) and alkaline liver phosphatase (ALP) were analysed. D-dimer was analysed using four different commercially available test kits.

RESULTS

In-hospital mortalities among patients with (n = 10) and without (n = 61) intestinal ischaemia were 40 % and 3 %, respectively (p = 0.003). D-dimer was associated with intestinal ischaemia (p = 0.001) independently of which assay was used. No patient presenting with a normal D-dimer had intestinal ischaemia. D-dimer >0.9 mg/L had a specificity, sensitivity and accuracy of 82 %, 60 % and 79 %, respectively. Total LD, isoenzymes of LD 1-4 and liver isoenzyme of ALP (ALP liver) were significantly higher in patients with intestinal ischaemia, and accuracies for LD 2 (cut-off 2.3 microkat/L) and ALP liver (cut-off 0.7 microkat/L) were 69 % and 66 %, respectively.

CONCLUSIONS

D-dimer may be used as an exclusion test for intestinal ischaemia, but lacks specificity. The other plasma biomarkers studied had insufficient accuracy for this group of patients. Further studies are needed.

D-dimer levels in the prediction of the degree of intestinal necrosis of etrangulated hernias in rats

PURPOSE

The aim of this study was to investigate the time-dependent relation between plasma D-dimer levels and the degree of intestinal necrosis and to compare these parameters with leukocyte counts in an experimental etrangulated hernia model in rats.

RESULTS

When the duration of intestinal ischemia was prolonged, serum D-dimer levels increased relative to the control group, with the difference being statistically significant at hour 2 (P = 0.027). In contrast, leukocyte counts in the 2- and 4-h strangulation group were higher that those of the control group, but the difference was not statistically significant (P = 0.625 and P = 0.846, respectively). However, in the 6-h strangulation group the levels of leukocytes were significantly higher that those of the control group (P = 0.015).

CONCLUSION

Serum D-dimer measurements may be used as a more valuable diagnostic parameter than leukocyte count in the early diagnosis of intestinal ischemia, including strangulated hernia.