Platelets in inflammatory bowel disease: clinical, pathogenic, and therapeutic implications

Platelet-to-lymphocyte percentage ratio for assessing disease activity and predicting therapeutic outcomes in ulcerative colitis

AIMS

Disease activity assessment and treatment outcome prediction are crucial in the patient management of ulcerative colitis (UC); yet the significance of platelet-to-lymphocyte percentage ratio (PLpR) remains unknown, which was investigated in this study.

METHODS

We used data from three clinical trials: ACT 1, PURSUIT, and UNIFI. In total, 7,614 endoscopic procedures and 1,365 patients were included for assessing severity and predicting outcome, respectively. The primary outcome was endoscopic remission, defined as a Mayo endoscopic score of 0. The diagnostic capacity of PLpR was evaluated by the area under the receiver operating characteristic curve (AUC) while multivariable logistic regression was employed to assess the prognostic power of PLpR.

RESULTS

PLpR showed higher AUCs than C-reactive protein in identifying endoscopic remission (P < 0.001) and improvement (P < 0.001). Besides, combining PLpR with fecal calprotectin enhanced the power to distinguish disease activity. In therapeutic outcome analyses, higher PLpR level indicated worse long-term outcomes. PLpR ≥ 1016.7 predicted a lower likelihood of endoscopic remission (OR: 0.50 [95 % CI: 0.39-0.65]; P < 0.001), endoscopic improvement (OR: 0.45 [95 % CI: 0.36-0.57]; P < 0.001), clinical remission (OR: 0.50 [95 % CI: 0.39-0.62]; P < 0.001), histologic improvement (OR: 0.50 [95 % CI: 0.31-0.79]; P = 0.004), and histologic-endoscopic mucosal improvement (OR: 0.42 [95 % CI: 0.27-0.66]; P < 0.001). Moreover, PLpR added the prognostic value to C-reactive protein, fecal calprotectin, clinical and endoscopic scores to predict long-term outcomes.

CONCLUSION

PLpR could be a promising biomarker for monitoring disease activity and predicting long-term therapeutic outcomes in UC.

Abnormal platelet parameters in inflammatory bowel disease: a systematic review and meta-analysis

BACKGROUND

Platelet dysfunction plays a critical role in the pathogenesis of inflammatory bowel disease (IBD). Despite clinical observations indicating abnormalities in platelet parameters among IBD patients, inconsistencies persist, and these parameters lack standardization for diagnosis or clinical assessment.

METHODS

A comprehensive search was conducted in the PubMed, Embase, Web of Science, and Cochrane Library databases for relevant articles published up to December 16th, 2023. A random-effects model was employed to pool the weighted mean difference (WMD) and 95% confidence interval (95% CI) of platelet count (PLT), mean platelet volume (MPV), platelet distribution width (PDW), and plateletcrit (PCT) between IBD patients and healthy controls, and subgroup analyses were performed.

RESULTS

The meta-analysis included 79 articles with 8,350 IBD patients and 13,181 healthy individuals. The results revealed significantly increased PLT and PCT levels (WMD: 69.910, 95% CI: 62.177, 77.643 109/L; WMD: 0.046%, 95% CI: 0.031%, 0.061%), and decreased MPV levels (WMD: -0.912, 95% CI: -1.086, -0.739 fL) in IBD patients compared to healthy individuals. No significant difference was found in PDW between the IBD and control groups (WMD: -0.207%, 95% CI: -0.655%, 0.241%). Subgroup analysis by disease type and disease activity showed no change in the differences for PLT, PCT, and MPV in the ulcerative colitis and Crohn's disease groups, as well as the active and inactive groups. Notably, the active group exhibited significantly lower PDW levels than the control group (WMD: -1.138%, 95% CI: -1.535%, -0.741%).

CONCLUSIONS

Compared with healthy individuals, IBD patients display significantly higher PLT and PCT and significantly lower MPV. Monitoring the clinical manifestations of platelet abnormalities serves as a valuable means to obtain diagnostic and prognostic information. Conversely, proactive measures should be taken to prevent the consequences of platelet abnormalities in individuals with IBD.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42023493848.

Analysis of the risk of future gastrointestinal surgery in Crohn's disease with stricture

BACKGROUND

Stricture in patients with Crohn's disease (CD) carries a high risk of CD-related surgery in the course of the disease. The aim of this study was to assess the rate of occurrence of CD-related surgery and to determine baseline risk factors predicting subsequent surgery in this patient group.

METHODS

Patients registered with stricturing CD were included. All baseline and follow-up data were collected retrospectively. Patients attended the clinic for follow-up at week 14 to assess their response to infliximab (IFX). CD-related surgery was the observational endpoint. Univariate and multivariate Cox regression analyses were used.

RESULTS

A total of 123 patients with stricturing CD were included in this study. The cumulative risk of CD-related surgery for years 1-5 after diagnosis was 18.0%, 26.7%, 32.6%, 40.7%, and 46.4%, respectively. Prior gastrointestinal (GI) surgery, low body mass index (BMI), and high platelet count might be risk factors for future CD-related surgery. With 97 participants treated by IFX, prior GI surgery and primary non-response (PNR) to IFX correlated with future CD-related surgery.

CONCLUSION

Prior GI surgery, BMI, and platelet counts were related to future CD-related surgery. Patients who were PNR to IFX had a higher risk of CD-related surgery in the future.

Serum Amyloid A as a Potential Biomarker in Inflammatory Bowel Diseases, Especially in Patients with Low C-Reactive Protein

The acute phase protein Serum Amyloid A (SAA) is synthesised by the liver in response to inflammatory stimuli. Previous studies have revealed that SAA may be a better biomarker of disease activity in inflammatory bowel disease (IBD) compared to C-reactive protein (CRP). This retrospective monocentric study evaluated whether SAA correlates with biomarkers like faecal calprotectin (FC), CRP, the Neutrophil to Lymphocyte ratio (NLR), the platelet count and clinical disease activity of IBD patients. Serum samples from the IBD outpatient clinic of the University Hospital Heidelberg were analysed for SAA concentrations if an FC concentration measurement was available from ±14 days to collection of the serum sample. Three hundred and six serum samples from 265 patients (166 with Crohn's disease, 91 with ulcerative colitis and 8 with IBD unclassified) met the inclusion criteria. There was a significant positive correlation between SAA and FC, CRP, NLR, platelet count and the Simple Clinical Colitis Activity Index (SCCAI). The cut-off for SAA serum concentration at 4.55 mg/L achieved a sensitivity of 57.5% and a specificity of 69.7% for the detection of active inflammation in IBD. SAA may be used as an additional biomarker in the disease monitoring strategy of IBD patients, especially in patients with low CRP concentrations.

Gut Microbiome-Generated Phenylacetylglutamine from Dietary Protein is Associated with Crohn's Disease and Exacerbates Colitis in Mouse Model Possibly via Platelet Activation

OBJECTIVES

Our aims were to better understand the interplay of diet and gut microbiota in Crohn's disease [CD], taking advantage of a new-onset treatment-naïve CD cohort. We focus on phenylacetylglutamine [PAGln], a diet-derived meta-organismal prothrombotic metabolite.

DESIGN

We collected faecal and serum samples from a CD cohort [n = 136] and healthy controls [n = 126] prior to treatment, and quantified serum PAGln using LC-MS/MS. Diet was assessed using food-frequency questionnaires. Mice [C57BL/6] were fed high/low-protein diets and administered dextran sodium sulphate [DSS] to examine plasma PAGly, thrombosis potential, and colitis severity. PAGly or saline was administered to DSS-induced colitis mice, and colitis severity and colonic tissue gene expression were examined. P-selectin and CD40L expression were determined in human platelet-rich plasma [n = 5-6] after exposure to platelet agonists following PAGln priming. Bioinformatic analysis and bacterial culturing identified the main contributor of PAGln in CD.

RESULTS

PAGln, a meta-organismal prothrombotic metabolite, is associated with CD. Administration of PAGly exacerbated colitis in a mouse model and upregulated coagulation-related biological processes. Antiplatelet medicine, dipyridamole, attenuated PAGly-enhanced colitis susceptibility. PAGln enhanced platelet activation and CD40L expression in platelet-rich plasma ex vivo. Further study revealed that high dietary protein intake and increased abundance of phenylacetic acid [PAA]-producing Proteobacteria mediated by phenylpyruvate decarboxylase act in concert to cause the elevated PAGln levels in CD patients.

CONCLUSION

Taken together, ppdc-carrying Proteobacteria-generated PAGln from dietary protein is associated with CD and exacerbates colitis possibly via platelet-induced coagulation and inflammation These results suggest that PAGln is a potential early diagnostic marker and therapeutic target of CD.

Platelet/Albumin ratio and plateletcrit levels are potential new biomarkers for assessing endoscopic inflammatory bowel disease severity

BACKGROUND

Endoscopy is currently recognized as the gold standard for assessing inflammatory bowel disease (IBD) severity. However, because the procedure is costly and invasive, endoscopy is not suitable for frequently monitoring intestinal inflammation. In this study, our aim was to identify noninvasive, low cost, and convenient biomarkers for identifying endoscopic IBD activity.

METHODS

In total, 246 patients with IBD (131 with Ulcerative colitis (UC) and 115 with Crohn's disease (CD)) and 369 healthy controls were recruited for this retrospective study. IBD activity was evaluated using endoscopic and clinical examinations. The potential of several inflammatory biomarkers, including platelets (PLT), plateletcrit (PCT), albumin (ALB), highly sensitive C-reactive protein (hs-CRP), erythrocyte sedimentation rate (ESR), and platelet-to-albumin ratio (PLT/ALB) to assess endoscopic IBD activity was evaluated using receiver operating characteristic (ROC) analyses.

RESULTS

PLT/ALB ratio, PLT, ALB, and hs-CRP levels were correlated with Mayo scores in UC patients, while PCT, PLT, fibrinogen (FIB), PLT/ALB ratio, hs-CRP, and ESR levels were correlated with Simple Endoscopic Scores for CD (SES-CD) in CD patients. ROC analyses showed that the area under the curve (AUC) value for the PLT/ALB ratio (0.705) was greater than hs-CRP (0.607) and ESR (0.552) values in UC patients. The AUC value for PCT (0.779) was greater than hs-CRP (0.698) and ESR (0.746) values in CD patients.

CONCLUSION

PLT/ALB ratio and PCT biomarkers were the most appropriate of all tested inflammatory biomarkers for assessing endoscopic IBD activity in UC and CD patients, respectively.

A different way to diagnosis acute appendicitis: machine learning

<b><br>Indroduction:</b> Machine learning is a branch of artificial intelligence based on the idea that systems can learn from data, identify patterns, and make decisions with minimal human intervention.</br> <b><br>Aim:</b> Our aim is to predict acute appendicitis, which is the most common indication for emergency surgery, using machine learning algorithms with an easy and inexpensive method.</br> <b><br>Materials and methods:</b> Patients who were treated surgically with a prediagnosis of acute appendicitis in a single center between 2011 and 2021 were analyzed. Patients with right lower quadrant pain were selected. A total of 189 positive and 156 negative appendectomies were found. Gender and hemogram were used as features. Machine learning algorithms and data analysis were made in Python (3.7) programming language.</br> <b><br>Results:</b> Negative appendectomies were found in 62% (n = 97) of the women and in 38% (n = 59) of the men. Positive appendectomies were present in 38% (n = 72) of the women and 62% (n = 117) of the men. The accuracy in the test data was 82.7% in logistic regression, 68.9% in support vector machines, 78.1% in k-nearest neighbors, and 83.9% in neural networks. The accuracy in the voting classifier created with logistic regression, k-nearest neighbor, support vector machines, and artificial neural networks was 86.2%. In the voting classifier, the sensitivity was 83.7% and the specificity was 88.6%.</br> <b><br>Conclusions:</b> The results of our study show that machine learning is an effective method for diagnosing acute appendicitis. This study presents a practical, easy, fast, and inexpensive method to predict the diagnosis of acute appendicitis.</br>.

The diagnostic role of preoperative blood tests in complicated appendicitis: A feasible approach to surgical decision

Background

An accurate diagnosis and timely surgical intervention have significant importance in noncomplicated appendicitis (NCA) and complicated appendicitis (CA). Therefore, any factor that helps in the prediction of CA also contributes to suitable treatment options.

Aim

This retrospective study aimed to identify any relationship between acute appendicitis (AA) and preoperative blood test levels and whether these parameters can differentiate between NCA and CA patients.

Patients and Methods

A database of 201 appendectomies and 100 control healthy patients was analyzed between 2019 and 2022. Patients were divided into three groups: NCA without peritonitis or phlegmonous appendicitis as group 1; CA with perforated, necrotizing appendicitis with peritonitis as group 2; and the healthy control group (CG) as group 3. White blood cell (WBC), platelet distribution width (PDW), mean platelet volume (MPV), red cell distribution width (RDW), creatine kinase (CK), and bilirubin levels were collected from the patients and compared statistically between the groups.

Results

Age, WBC, and PDW levels were set as predictive in the differential diagnosis of CA as a result of receiver operating characteristic (ROC) analysis. The multivariate analysis demonstrated that age (OR: 1.023; 95% CI: 1.000-1.045; P = 0.04), male sex (OR: 3.718; 95% CI: 1.501-9.213; P = 0.005), WBC levels (OR: 1.000; 95% CI: 1.000-1.000; P = 0.002), and PDW levels (OR: 2.129; 95% CI: 1.301-3.484; P = 0.003) were independently associated with CA.

Conclusion

Age, higher WBC count, and PDW levels are valuable in differentiating the diagnosis of CA from NCA, and this could be a feasible approach for surgical decisions.

GLP-1 Receptor Agonists in Obese Patients with Inflammatory Bowel Disease: from Molecular Mechanisms to Clinical Considerations and Practical Recommendations for Safe and Effective Use

PURPOSE OF REVIEW

To discuss current literature and provide practical recommendations for the safe and effective use of glucagon-like peptide 1 receptor agonists (GLP-1 RA) in people with inflammatory bowel disease (IBD) and type 2 diabetes (T2D) and/or obesity. The molecular mechanisms that justify the potential benefits of GLP-1 RA in IBD and the links between IBD, obesity, and cardiovascular disease are also discussed.

RECENT FINDINGS

Preliminary data suggest that GLP-1 RA can modulate crucial pathways in the pathogenesis of IBD, such as chronic inflammation circuits, intestinal tight junctions, and gut microbiome dysbiosis, setting the stage for human trials to investigate the role of these agents in the treatment of IBD among people with or without diabetes and obesity. However, gastrointestinal side effects related to GLP-1 RA need appropriate clinical management to mitigate risks and maximize the benefits of therapy in people with IBD. GLP-1 RA originally emerged as drugs for the treatment of hyperglycemia and are currently licensed for the management of T2D and/or overweight/obesity. However, their wealth of pleiotropic actions soon raised expectations that they might confer benefits on non-metabolic disorders. Future studies are expected to clarify whether GLP-1 RA deserve an adjunct place in the arsenal of drugs against IBD.

Evaluation of the performance of simple laboratory parameters used in the diagnosis of acute appendicitis

Background

Acute appendicitis (AA) is one of the most common emergency surgery.

Aim

To evaluate the performance of laboratory parameters used in the diagnosis of AA.

Subjects and Methods

There were two groups. In both groups, leukocyte (WBC), neutrophil, lymphocyte count, neutrophil/lymphocyte ratio (NLR), mean platelet volume (MPV), red cell distribution width (RDW), and platelet distribution width (PDW) values were examined in complete blood count (CBC). In addition, serum bilirubin (total bilirubin and direct bilirubin) values were examined. All laboratory parameters studied were compared to evaluate their diagnostic performance.

Results

A total of 128 people were in the AA group and 122 people were in the healthy group (control). WBC count, neutrophil count, NLR, total bilirubin, direct bilirubin, and PDW values were significantly higher in the AA group than in the control group (P value <0.05). Lymphocyte counts and MPV values in the AA group were significantly lower than in the control group (P value <0.05). The sensitivity and selectivity of the WBC and neutrophil counts in AA were 95.13%, 89.34%, 94.53%, and 93.44%, respectively. The sensitivity and selectivity of the total bilirubin values were 59.38% and 73.77%, respectively. Area under the ROC curve (AUC) values within 95% confidence interval were over 0.900 for neutrophil count, WBC count, direct bilirubin, NLR, and PDW values. AUC values for total bilirubin, lymphocyte count, RDW, and MPV values were below 0.700.

Conclusions

Diagnostic performances of the laboratory parameters were determined as follows: neutrophil count > WBC count > direct bilirubin = NLR = PDW > total bilirubin = lymphocyte count = RDW = MPV.

Platelet, Mean Platelet Volume and Platelet Distribution Width Levels Might Be a Promising Marker for the Prediction of Disease Severity, Mucosal Healing and Steroid Dependence in Patients With Ulcerative Colitis

BACKGROUND/AIMS

In this study, we aimed to determine the value of mean platelet (PLT) volume (MPV), PLT and PLT distribution width (PDW) levels as a marker in the prediction of mucosal healing (MH), steroid resistance (SR) and steroid dependence (SD) in newly diagnosed moderate and severely active patients with ulcerative colitis (UC), who did not receive medical treatment before.

PATIENTS/METHODS

Two hundred forty-nine patients with severely or moderately active UC and 50 healthy subjects were enrolled in the study after retrospective analysis. Disease severity and MH of UC were determined according to the Mayo Score. According to the results of remission induction therapy, the patients were divided into two groups: Group 1; MH positive and Group 2; MH negative. UC patients with clinical remission (CR) but without MH were divided into two subgroups SD and non-SD during their follow-up. These two groups and subgroups were compared for variables.

RESULTS

42.6% of patients with UC had severe disease activation. 44.6% of patients with UC had pancolitis. After remission induction therapy, CR was observed in 84.3% of patients with UC. MH rate was 53.0%. SR rate was 15.7% and the SD rate was 16.1%. A strong positive correlation was observed between C reactive protein (CRP), PLT and Mayo score in the activation period (r=0.835 and p<0.001; r=0.883 and p<0.001; respectively). A strong negative correlation was observed between mean PLT volume (MPV), PDW levels and Mayo score (r=-0.905 and p<0.001; r=-0.805 and p<0.001; respectively). According to the receiver operating characteristic curve (ROC) analysis, PLT had a sensitivity of 42.4% and a specificity of 22.7% in the prediction of MH at a cut-off value of 266.5x10³/µL. MPV had a sensitivity of 83.5% and a specificity of 73.5% in the prediction of MH at a cut-off value of 8.05 fL. PDW had a sensitivity of 88.6% and a specificity of 84.5% in the prediction of MH at a cut-off value of 2.95 fL. PLT was determined with 92.5% sensitivity and 86.8% specificity in the prediction of SD at a cut-off value of 287.0x10³/µL. MPV had a sensitivity of 86.8% and a specificity of 67.5% in the prediction of SD at a cut-off value of 7.95 fL. PDW had a sensitivity of 73.7% and a specificity of 72.5% in the prediction of SD at a cut-off value of 12.55 fL.

CONCLUSIONS

There was a positive correlation between PLT levels and Mayo score, and a negative correlation between Mayo score and MPV or PDW levels. We think that PLT, MPV and PDW levels may be promising markers in the evaluation of disease activation/remission and severity. We believe that PLT, MPV and PDW levels will be determinative especially in the exclusion of SD, for UC patients with CR but without MH.

Assessment of the utility of platelet indices to diagnose clinical benign prostatic hyperplasia in dogs

Introduction

Platelet indices changes in severely ill people and in dogs with inflammation are compatible findings. This study aimed to compare platelet indices between dogs with clinical benign prostatic hyperplasia (BPH) and healthy controls. Additionally, to determine whether there is a correlation between the relative prostatic size (S _rel) and the platelet indices in BPH dogs.

Methods

Thirty-five adult intact male dogs of different breeds were allocated to the experimental groups: dogs with clinical BPH (groups A; n = 24; median age of 6 years; the median weight of 8.50 kg) and healthy dogs (group B; n = 11; median age 5.50 years; the median weight of 7.00 kg) based on physical examination, clinical signs, and S _rel detected by ultrasonographic findings. The individual prostatic volume (IPV) was divided by the expected prostatic volume (EPV) to determine the relative prostatic size in dogs over 4 years old. Platelet indices were compared between the two groups, and a correlation between S _rel and these indices was calculated.

Results

The median S _rel of dogs in group A was significantly higher (P = 0.001), and the mean plateletcrit (PCT) was significantly lower (P = 0.003) compared with those in group B. S _rel showed a significant negative correlation with PLT and PCT (r = -0.388; P = 0.02 and r = -0.402; P = 0.01). Receiver operating characteristic (ROC) analysis showed PLT and PCT thresholds for estimating S _rel > 1 with 75% and 87.5% sensitivity and 71.82 and 63.64% specificity.

Discussion

The findings of this study support the use of platelet indices like PLT and PCT to detect clinical BPH in dogs. However, more research is needed to confirm their utility in conjunction with other previously described diagnostic factors.

Effects of acute inflammation on platelet indices: An experimental study

Background and objective: It is well known that inflammation may affect the platelets. However, there are inconsistencies between the results of observational studies investigating changes in platelet indices in inflammatory conditions. This study aimed to investigate the possible effects of acute inflammation on platelet indices in plantar inflammation model in rats. Methods: A total of 10 rats, 5 in each group, were used in the study. Lambda-carrageenan and saline were applied subcutaneously to the right hind paw of the rats in the inflammation group and in the control group, respectively. Six hours after the administration, blood samples were taken from femoral arteries and femoral veins, and platelet indices were measured by a hematology analyzer. In addition, plantar tissue samples belonging to the control and inflammation groups were evaluated histopathologically. Results: On histopathological examination, no pathological condition was observed in the control group, while there were changes consistent with acute inflammation in the lambda-carrageenan-injected group. There was no significant difference in terms of platelet indices between both the arterial and vein samples and between the control and inflammation groups. Conclusions: Our results suggest that platelet indices cannot be used in the diagnosis of acute inflammatory conditions. However, in our opinion, these findings must not be interpreted as that acute inflammation does not affect platelet number and volume. Instead, we believe that it may be more appropriate to say that acute inflammation does not produce a quantitatively significant change in platelet indices due to the combination of the opposite effects.

Development and validation of a nomogram to predict indolent course in patients with ulcerative colitis: a single-center retrospective study

Background

The natural disease course for patients with ulcerative colitis (UC) is heterogeneous and few data are available on the indolent course of UC and its related factors. We aimed to develop and validate a nomogram to predict indolent course in patients with UC.

Methods

Data of patients diagnosed with UC in the First Affiliated Hospital of Sun Yat-sen University (Guangzhou, China) between April 2007 and February 2021 were retrospectively analysed. Indolent course was defined as a disease course without need for strict interventions (steroids, immunomodulators, biological agents, hospitalization, or surgery therapy) during the follow-up period. The whole cohort was randomly divided into training set and validation set. The nomogram was constructed in the training set based on the results of univariate and multivariate Cox regression analyses. The performance of the nomogram was assessed by the concordance index (C-index), area under the receiver-operating characteristic curve (AUC), and calibration plots. In addition, we internally validated the nomogram via the bootstrap method and the validation set.

Results

Of 969 treatment-naive patients with UC, 771 (79.6%) had an indolent course after diagnosis. Of these, 313 patients were included in the development and validation of the nomogram. The nomogram incorporating age, disease activity, C-reactive protein, and platelet count showed good calibration and discrimination. The C-index was 0.759 (0.741 in bootstrap validation) and the AUC at 2, 4, and 6 years was 0.767, 0.782, and 0.775, respectively. The nomogram performed well when applied to the validation set.

Conclusion

A majority of patients with UC had an indolent course after diagnosis. The nomogram developed in this study might be useful in therapeutic decision-making and follow-up management for patients with UC.

Platelets as Key Factors in Inflammation: Focus on CD40L/CD40

Platelets are anucleate cytoplasmic fragments derived from the fragmentation of medullary megakaryocytes. Activated platelets adhere to the damaged endothelium by means of glycoproteins on their surface, forming the platelet plug. Activated platelets can also secrete the contents of their granules, notably the growth factors contained in the α-granules, which are involved in platelet aggregation and maintain endothelial activation, but also contribute to vascular repair and angiogenesis. Platelets also have a major inflammatory and immune function in antibacterial defence, essentially through their Toll-like Receptors (TLRs) and Sialic acid-binding immunoglobulin-type lectin (SIGLEC). Platelet activation also contributes to the extensive release of anti- or pro-inflammatory mediators such as IL-1β, RANTES (Regulated on Activation, Normal T Expressed and Secreted) or CD154, also known as the CD40-ligand. Platelets are involved in the direct activation of immune cells, polynuclear neutrophils (PNNs) and dendritic cells via the CD40L/CD40 complex. As a general rule, all of the studies presented in this review show that platelets are capable of covering most of the stages of inflammation, primarily through the CD40L/CD40 interaction, thus confirming their own role in this pathophysiological condition.

Inflammatory Indexes for Assessing the Severity and Disease Progression of Ulcerative Colitis: A Single-Center Retrospective Study

BACKGROUND

Active and severe ulcerative colitis (UC) and non-response to 5-aminosalicylic acid (5-ASA) are related to poor outcomes and should be accurately identified. Several integrated inflammatory indexes are potentially useful to assess the disease severity in patients with acute or critical diseases but are underexplored in patients with UC.

METHODS

Patients with UC consecutively admitted to our hospital between January 2015 and December 2020 were retrospectively grouped according to the activity and severity of UC and response to 5-ASA. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), systemic immune-inflammation index (SII), neutrophil-to-platelet ratio (NPR), platelet-to-albumin ratio (PAR), C-reactive protein-to-albumin ratio (CAR), and C-reactive protein-to-lymphocyte ratio (CLR) were calculated. The areas under receiver operating characteristic curves (AUC) were calculated.

RESULTS

Overall, 187 patients with UC were included, of whom 151 were active, 55 were severe, and 14 were unresponsive to 5-ASA. The active UC group had significantly higher NLR, PLR, SII, and PAR levels. SII had the greatest predictive accuracy for active UC, followed by PLR, PAR, and NLR (AUC = 0.647, 0.641, 0.634, and 0.626). The severe UC group had significantly higher NLR, PLR, SII, PAR, CAR, and CLR levels. CLR had the greatest predictive accuracy for severe UC, followed by CAR, PLR, SII, NLR, and PAR (AUC = 0.732, 0.714, 0.693, 0.669, 0.646, and 0.63). The non-response to the 5-ASA group had significantly higher CAR and CLR levels. CAR had a greater predictive accuracy for non-response to 5-ASA than CLR (AUC = 0.781 and 0.759).

CONCLUSION

SII, CLR, and CAR may be useful for assessing the severity and progression of UC, but remain not optimal.

Case controlled study on diagnostic predictive value of inflammatory markers of complete blood count in pregnant women with acute appendicitis

The aim of this study is to evaluate and compare the diagnostic ability of platelet-related parameters and white cell-based parameters in pregnant women with appendicitis. This is a retrospective case-controlled study. Women aged between 18 and 50-years-old who had undergone appendectomy between January 2010 and January 2021 were enrolled in the study. Age, pathological diagnosis and relevant laboratory parameters were recorded for each patient. Gestational characteristics were recorded for pregnant patients. There were 58 pregnant and 1171 non-pregnant women enrolled. Pregnant women with acute appendicitis were significantly younger (p < .0001, d= -0.532), had significantly lower PLT (p = .002, d= -0.428) and ALC (p = .033, d= -.304) levels but had significantly higher MPV (p = .004, d = .415) levels than non-pregnant counterparts. In pregnant women, only MPV was the independent predictor of acute appendicitis (OR: 1,952). MPV cut-off value of 9,6 fL provided 63,5% sensitivity, 67,7% specificity, 94,2% PPV and 17,3% NPV whereas 10 fL provided 55,8% sensitivity, 100% specificity, 100% PPV and 21,4% NPV for acute appendicitis in pregnant women. Therefore, MPV might be useful for diagnosing acute appendicitis in pregnant women.Impact statementWhat is already known on this subject? In pregnant women, counts and percentages of white blood cells and neutrophils are known to be independent predictors of acute appendicitis. Meanwhile, physiologic leukocytosis of gestation is a challenge for interpretation of these parameters. Platelets and related markers are, as well, predictive for inflammatory processes in the human body.What do the results of this study add? The role of platelet-related markers in the diagnosis of acute appendicitis in pregnant women has not been studied previously. The results of the present study indicate that in pregnant women, changes in mean platelet volume might be an independent predictor of acute appendicitis.What are the implications of these findings for clinical practice and/or further research? Further similar large-scale case-controlled or cohort studies are required to validate the present results. In pregnant women with abdominal pain, the use of mean platelet volume as a biomarker could reduce negative laparotomy rates. A mean platelet volume is a useful tool for diagnosing acute appendicitis in pregnant women and provides helpful guidance for clinicians dealing with these patients in the emergency room.

Anti-TNF-α Treatment Reduces the Baseline Procoagulant Imbalance of Patients With Inflammatory Bowel Diseases

BACKGROUND

Inflammatory bowel diseases (IBD) are characterized by an increased thrombosis risk of uncertain etiology. Coagulation derangement arising from inflammation may be a triggering factor. We hypothesized that strong inflammation inhibitors (eg, anti-tumor necrosis factor-α drugs) may affect coagulation.

METHODS

Forty patients with IBD were compared with 57 control patients for coagulation factors and endogenous thrombin potential (ETP), the latter being the most sensitive marker of in vivo pro- and anticoagulation balance. We measured ETP in the presence and absence of thrombomodulin (the physiologic protein C [PC] activator). Coagulation at different timepoints was also assessed for 28 of these patients during infliximab treatment.

RESULTS

The median ETP (nM thrombin × minutes) and range (minimum-maximum) were each higher in patients at baseline than in control patients in both the absence (2120 [1611-3041] vs 1865 [1270-2337]) and the presence (1453 [464-2522] vs 831 [104-1741]) of thrombomodulin. The ETP ratio (with/without thrombomodulin) was high at baseline (0.73 [0.21-0.90] vs 0.45 [0.07-0.85]). The ETP and ETP ratio declined during treatment and were significantly lower at the end than at baseline. Factor (F) VIII and fibrinogen, which were high at baseline, decreased during treatment and at the end were significantly lower than at baseline. The FVIII/PC ratio, which was high in patients at baseline, declined during treatment and at the end was lower than at baseline. C-reactive protein recorded at the end of treatment was lower than at baseline.

CONCLUSIONS

Patients with IBD have a procoagulant imbalance as shown by increased ETP at baseline. The ETP decreases during treatment with infliximab, which is related to decreased FVIII and FVIII/PC ratio. This effect is also related to the improvement of inflammation as shown by decreased fibrinogen and C-reactive protein.

Perioperative parenteral fish oil supplementation improves postoperative coagulation function and outcomes in patients undergoing colectomy for ulcerative colitis

OBJECTIVE

Ulcerative colitis (UC) is an independent risk factor for thromboembolism, especially during the perioperative period. This study aimed to determine the effects of perioperative parenteral nutrition (PN) supplemented with fish oil (FO) on coagulation function and postoperative outcomes in patients with UC.

METHODS

This retrospective cohort included 92 consecutive patients who underwent colectomy for UC. Postoperative coagulation indices and outcomes, including thromboelastography (TEG) findings and comprehensive complication index (CCI), were compared. The relative change in serum D-dimer (ΔD-dimer) levels and maximal amplitude (ΔMA) on TEG were also determined.

RESULTS

Patients receiving PN supplemented with FO (n = 48) had lower D-dimer (P = .036) levels on postoperative day (POD) 5 and a higher MA (P < 0.001) on POD 1 than those who did not receive it (n = 44). A lower ΔD-dimer level (P = .048) and ΔMA (P < 0.001) were also observed in patients receiving FO. The incidence of major postoperative complications (6.3 vs 22.7%; P = .017) and CCI (20.9 vs 23.4%; P = .044) were significantly lower in patients receiving FO. In multivariate analysis, FO (odds ratio, 0.231; 95% confidence interval, 0.055-0.971; P = .046) was a positive protector of major postoperative complications.

CONCLUSION

Perioperative PN supplemented with FO improved coagulation function and reduced major postoperative complications in patients with UC requiring colectomy. These results may provide cues in formulating management strategies for preventing thromboembolisms and postoperative complications in patients with UC.

Predictive Factors to Diagnose Appendicitis in Children in the Emergency Department

Introduction

The most common surgical condition in children is appendicitis. However, making a diagnosis can be difficult due to poor communication and difficulty in the physical examination.

Objective

This study aimed to determine the accurate clinical predictive factors for the diagnosis of appendicitis in children in the emergency department (ED).

Methods

A retrospective cohort study was conducted from January 2015 to December 2019. The electronic medical records were reviewed from 1043 pediatric patients younger than 15 years with the chief complaint of abdominal pain and were admitted to the ED during the study period. The patients were divided into either the appendicitis group or non-appendicitis group. The two groups were compared in terms of baseline characteristics, abdominal symptoms and signs, symptom durations, laboratory results, final diagnosis, treatment in the ED, ED disposition, morbidity, and mortality. The significant predictive factors for the diagnosis of appendicitis were examined using univariate and multivariate analyses by logistic regression.

Results

Predictive factors for the diagnosis of appendicitis in pediatric patients with abdominal pain were gradual increase in abdominal pain (odds ratio (OR) 3.38, 95% confidence interval (CI) 1.51–7.58), right lower quadrant abdominal tenderness (OR 21.07, 95% CI 9.12–48.67), presentation of peritoneal irritation signs (OR 12.57, 95% CI 5.28–29.92), and an absolute neutrophil count >75% (OR 4.68, 95% CI 2.3–9.51). The significant variables were used to develop a diagnostic predictive probability scoring system that ranged from 0.05 to 0.95. The receiver operating characteristic curve indicated a cut-off point of 0.089 to predict pediatric appendicitis with an area under the curve of 0.963.

Conclusion

The predictive factors for diagnosing appendicitis in children are useful in determining which children require surgical intervention. However, the clinical symptoms and physical examination of the abdomen continue to be the most important diagnostic tools for the diagnosis of appendicitis in children.

Thromboembolic and atherosclerotic cardiovascular events in inflammatory bowel disease: epidemiology, pathogenesis and clinical management

Inflammatory bowel disease (IBD) is associated with an increased risk of cardiovascular disease (CVD). The increased risk of CVD concerns an increased risk of venous thromboembolism (VTE), atherosclerotic cardiovascular disease (ASCVD) and heart failure (HF), at corresponding relative risks of 2.5, 1.2 and 2.0, respectively, as compared with the general population. Especially young patients under the age of 40 years run a relatively high risk of these complications when compared with the general population. Chronic systemic inflammation causes a hypercoagulable state leading to the prothrombotic tendency characteristic of VTE, and accelerates all stages involved during atherogenesis in ASCVD. Increased awareness of VTE risk is warranted in patients with extensive colonic disease in both ulcerative colitis and Crohn's disease, as well as during hospitalization, especially when patients are scheduled for surgery. Similarly, critical periods for ASCVD events are the 3 months prior to and 3 months after an IBD-related hospital admission. The increased ASCVD risk is not fully explained by an increased prevalence of traditional risk factors and includes pro-atherogenc lipid profiles with high levels of small dense low-density lipoprotein cholesterol particles and dysfunctional high-density lipoprotein cholesterol. Risk factors associated with HF are location and extent of inflammation, female sex, and age exceeding 40 years. A dose-dependent increase of overall CVD risk has been reported for corticosteroids. Immunomodulating maintenance therapy might reduce CVD risk in IBD, not only by a direct reduction of chronic systemic inflammation but possibly also by a direct effect of IBD medication on platelet aggregation, endothelial function and lipid and glucose metabolism. More data are needed to define these effects accurately. Despite accumulating evidence on the increased CVD risk in IBD, congruent recommendations to develop preventive strategies are lacking. This literature review provides an overview of current knowledge and identifies gaps in evidence regarding CVD risk in IBD, by discussing epidemiology, pathogenesis, and clinical management.

Hepatic mosaic enhancement pattern correlates with increased inflammatory activity and adverse therapeutic outcomes in patients with Crohn's disease

PURPOSE

This study aimed to evaluate the role of hepatic mosaic enhancement pattern (HMEP) on computed tomography images in the disease activity and therapeutic outcome of Crohn's Disease (CD).

METHODS

Twenty-five CD patients with HMEP comprised the HMEP group, and 25 CD patients without HMEP, who had a similar onset age, sex, and disease course with those in the HMEP group, comprised the non-HMEP group. No underlying liver/biliary disease was observed in any of the patients. Clinical characteristics, laboratory test results, Lémann index, and CD endoscopic index of severity (CDEIS) were compared between the groups using the Student t-, Mann-Whitney U, Chi square, or Fisher's exact tests. Patients received top-down, step-up, or traditional treatment during the follow-up period. After the 1-year follow-up, therapeutic outcomes (active inflammation [CDEIS > 3.5 if the endoscopic data were available, or C-reactive protein level > 5 mg/L if the endoscopic data were unavailable] or remission) were evaluated.

RESULTS

The occurrence rate of fistulas/abscesses was higher in the HMEP group (84%, 21/25) than in the non-HMEP group (48%, 12/25) with no statistical significance (P = 0.056). The HMEP group showed a higher C-reactive protein level (P = 0.001), erythrocyte sedimentation rate (P = 0.013), and blood platelet count (P = 0.005). There was no significant difference in therapeutic strategies between the groups (P = 0.509). The HMEP group showed a significantly lower remission ratio after anti-inflammatory treatment than the non-HMEP group (P = 0.045).

CONCLUSIONS

HMEP was correlated with increased inflammatory activity and adverse therapeutic outcomes in CD. This finding provided insights regarding novel markers of CD diagnosis and treatment.

Role of platelet indices as a biomarker for the diagnosis of acute appendicitis and as a predictor of complicated appendicitis: A meta-analysis

Introduction

Acute appendicitis is one of the most common surgical emergencies worldwide. Clinical scoring system systems have been developed to diagnose acute appendicitis, but insufficient to predict the complication. The amount of serum biomarkers elevates in response to acute inflammation, which could be beneficial for diagnostic tools. Accordingly, a meta-analysis was conducted to evaluate the efficacy of platelet indices, including mean platelet volume (MVP) and platelet distribution width (PDW) as potential biomarkers for the diagnosis of a diagnosis of acute appendicitis.

Material and methods

The dataset was defined by searching for articles published until December 2020 from PubMed, EMBASE, Google Scholar and the Cochrane database. The meta-analysis was performed using Review Manager Software version 5.4.1.

Results

The final analysis was made from 9 studies, including 3124 patients. The results demonstrated that lower MPV values was significantly associated with acute appendicitis (odds ratio (OR) = 0.81, 95% confidence interval (CI) = −1.51 to −0.11, P = 0.02), but not associated with complicated appendicitis by comparing it with the control (OR = −0.13,95% CI = −0.33 to −0.07, P = 0.19) and non-complicated appendicitis groups (OR = −0.13,95% CI = −0.30 to −0.04, P = 0.14). The present study failed to demonstrate the diagnostic value of PDW for the prediction of appendicitis and its complication.

Conclusion

The results of the meta-analysis strongly indicate that a lower MVP values could function as a marker for predicting the acute appendicitis.

•

Platelet play an important role in the response to systemic inflammation and sepsis.

•

Inflammatory process activated platelets destruction consequence in the release of small platelets into bloodstream.

•

This studycompared the association between the platelet indices and the diagnosis of acute appendicitis.

•

Lower mean platelet volume(MVP) is a significant diagnostic marker for acute appendicitis.

Predictive values of biochemical markers as early indicators for severe COVID-19 cases in admission

Aim: COVID-19 is a pandemic that causes high morbidity and mortality, especially in severe patients. In this study, we aimed to search and explain the relationship between biochemical markers, which are more common, easily available and applicable to diagnose and to stage the disease. Materials & methods: In this study, 609 patients were evaluated retrospectively. 11 biochemical parameters were included in analysis to explain the relationship with severity of disease. Results: Nearly, all the parameters that have been evaluated in this study were statistically valuable as a predictive parameter for severe disease. Areas under the curve of blood urea nitrogen (BUN)/albumin ratio (BAR), CALL score and lymphocyte/C-reactive protein ratio were 0.795, 0.778 and 0.770. The BAR and neutrophil/albumin ratios provide important prognostic information for decision-making in severe patients with COVID-19. Conclusion: High BAR and neutrophil/albumin ratios may be a better predictor of severity COVID-19 than other routinely used parameters in admission.

BODY IRON STATUS INDICATORS AND INFLAMMATION INDICATORS DURING INFLAMMATORY BOWEL DISEASE THERAPY IN CHILDREN AND ADOLESCENTES

BACKGROUND

The treatment of patients with inflammatory bowel disease (IBD) consists of the induction and maintenance remission of the disease. Iron status indicators would be useful for the diagnosis of iron deficiency anemia, whereas the inflammation indicators would be for the diagnosis of chronic disease anemia.

OBJECTIVE

To assess body iron status indicators and inflammation indicators during the treatment of IBD, consisted of conventional or infliximab therapy in children and adolescents.

METHODS

A case-control study of a sample of 116 individuals, of which 81 patients with IBD, 18 of them receiving conventional therapy, 20 infliximab therapy, and 43 who were in remission of the disease, and 35 healthy (control group) children and adolescents. Iron status and inflammation indicators were investigated at baseline, and 2 and 6 months of both therapies - conventional and infliximab.

RESULTS

The mean age was 12.1±4.3 years. At baseline, both groups - conventional therapy and infliximab - presented significant differences in most markers studied compared to the control group. After 2 months of conventional therapy, hemoglobin and serum iron levels were lower than those of the control group; and red cells distribution width (RDW), total iron-binding capacity, transferrin receptor/ferritin ratio, and interleukin-6 were higher than the control group. After 2 months of infliximab treatment, hemoglobin and serum iron levels were lower than those of the control group; and RDW, soluble transferrin receptor, soluble transferrin receptor/ferritin ratio, and interleukin-6 were higher than the control group. After 6 months of conventional therapy, hemoglobin and serum iron levels were lower than those of the control group, and RDW and interleukin-6 were higher than those of the control group. After 6 months of infliximab treatment, the hemoglobin and serum iron levels were lower than the control group, and RDW, soluble transferrin receptor, soluble transferrin receptor/ferritin ratio, erythrocyte sedimentation rate, and platelets were higher than the control group. Regarding patients under treatment for at least one year (remission group), all markers studied, except transferrin, were similar to the control group.

CONCLUSION

In conclusion, there were some contradictions among the different body iron status indicators and inflammation indicators at two and 6 months of treatment with conventional and infliximab therapy, however after one year of treatment, as shown by the remission group, all indicators studied, except transferrin, were similar to healthy children and adolescents.

Effective immune-inflammation index for ulcerative colitis and activity assessments

BACKGROUND

The inverse association between systemic immune-inflammation index (SII) and overall survival in tumors has been studied.

AIM

To evaluate the hematological indexes for assessing the activity of ulcerative colitis (UC).

METHODS

In this case-control study, 172 UC patients and healthy participants were included. Comparisons were made among groups of white blood cells, hemoglobin, platelets, neutrophils, lymphocytes, monocytes, SII, neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR). The relationship with hematological inflammation was verified by Spearman correlation analyses. The efficiency of SII, NLR, and PLR for distinguishing between UC and severe disease status was assessed by the receiver operator curve and logistic regression analyses.

RESULTS

The values of SII, NLR, and PLR were higher in UC patients than in controls (P < 0.001) and were positively correlated with the Mayo endoscopic score, extent, Degree of Ulcerative Colitis Burden of Luminal Inflammation (DUBLIN) score, and Ulcerative Colitis Endoscopic Index of Severity (UCEIS). The cut-off NLR value of 562.22 predicted UC with a sensitivity of 79.65% and a specificity of 76.16%. Logistic regression analysis revealed that patients with SII and NLR levels above the median had a significantly higher risk of UC (P < 0.05). Risk factors independently associated with DUBLIN ≥ 3 included SII ≥ 1776.80 [odds ratio (OR) = 11.53, P = 0.027] and NLR value of 2.67-4.23 (OR = 2.96, P = 0.047) on multivariate analysis. Compared with the first quartile, SII ≥ 1776.80 was an independent predictor of UCEIS ≥ 5 (OR = 18.46, P = 0.012).

CONCLUSION

SII has a certain value in confirming UC and identifying its activity.

Platelet-to-lymphocyte percentage ratio index: a simple non-invasive index to monitor the endoscopic activity in Crohn's disease

BACKGROUND

Recent evidence has shown that the complete blood count (CBC) is abnormal in patients with Crohn's disease (CD). We aimed to investigate an effective CBC parameter and explore its impact on disease activity in a large CD cohort.

METHODS

We performed a retrospective analysis of patients with established CD who underwent clinically indicated endoscopy at four tertiary centres in China between 2016 and 2020. Individual variables of the Simple Endoscopic Score for CD, CBC parameters, C-reactive protein (CRP) levels, erythrocyte sedimentation rate, and faecal calprotectin (FC) were independently reviewed by different investigators. The hold-out method was used to verify the predictive power of the established model.

RESULTS

Data from a total of 1388 endoscopic procedures performed for 882 eligible CD patients were available with routine blood parameters and related indicators. The model using platelet-to-lymphocyte percentage ratio (PLpR) had high accuracy for identifying patients in endoscopic remission (ER), with an area under the curve (AUC) of 0.785 [95% confidence interval (CI): 0.784-0.787], which was comparable with that for CRP (AUC: 0.775, 95% CI: 0.774-0.777). Notably, the AUC of PLpR was significantly higher than that of CRP in patients with colonic disease and with a history of surgery. Moreover, after combining the FC with PLpR, the AUC value of FC + PLpR increased up to 0.892 (95% CI: 0.890-0.894) for identifying ER.

CONCLUSIONS

We explored an index (PLpR) to identify CD patients in ER based on platelet and lymphocyte percentage from the CBC. PLpR helped evaluate the degree of disease activity and monitor the therapeutic response.

Laboratory Assessment of Disease Activity in Pediatric Patients with Inflammatory Bowel Disease: What’s New?

Laboratory tests are an integral part of both the diagnostic and follow-up algorithm of patients with inflammatory bowel disease (IBD). Their advantages over other non-invasive methods for assessing disease activity are greater objectivity than clinical activity indices and imaging studies. This review aims to analyze shortly the most common laboratory tests used to assess disease activity in pediatric patients with IBD. In addition to the conventional blood and serum markers that are not specific for gut inflammation, although routinely used, we also reviewed the established fecal markers such as calprotectin, lactoferrin, M2-pyruvate kinase, osteoprotegerin, HMGB1, chitinase 3-like 1, and the promising non-coding microRNA. In conclusion, neither marker is unique to the pediatric IBD. More clinical data are required to assess biomarkers’ full potential for diagnosis, management, and follow-up of pediatric IBD patients.

Inflammatory bowel disease and the risk of cardiovascular diseases

Inflammatory bowel disease (IBD) includes both ulcerative colitis and Crohn's disease, which are well recognised as chronic systemic and immune-mediated conditions that frequently involve extraintestinal manifestations. Although comorbidities have long been the subject of research in other chronic inflammatory diseases, this concept is also emerging in IBD. Many pathologies have been linked to IBD, including cardiovascular disease, which is the main cause of death in developed countries. IBD patients are at increased risk of conditions such as early atherosclerosis and myocardial infarction or venous thrombosis and pulmonary thromboembolism. The aim of this review is to make an approximation of the physiopathology of the different manifestations of cardiovascular disease in patients with IBD and how to prevent them.

Predictive value of laboratory parameters in childhood migraine

Migraine is a neurovascular disease characterized by inflammation of the cerebral and extra cerebral vessels and appears in the form of attacks. Although the pathophysiology of migraine is not fully known, the data obtained because of long-term studies reliably support the presence of a potential relationship between migraine pathogenesis and platelet biology. The aim of this study was to investigate the effect of migraine on MPV and other blood parameters as well as the relationship between the hematologic parameters and characteristics of the headache and whether they possess diagnostic value as inflammation and platelet biology play a fundamental role in the disorder. The study group consisted of 56 patients who were followed up and treated with a diagnosis of migraine and 45 healthy patients. The median creatinine, CRP and TSH values of the children in the migraine group were found to be statistically significantly higher than the healthy control group. Serum iron levels of the migraine group were found to be statistically significantly lower than the control group. No statistically significant difference was found between the two groups in terms of MPV. However, when we examined only the patient group, we found MPV to be statistically significantly higher in girls. Increased MPV and decreased serum iron levels may be related to migraine. More comprehensive studies including a larger population are required to evaluate the specific parameters that may guide the follow-up and treatment of the disorder with simple tests to be used in routine practice and to elucidate the underlying pathophysiology.

Antiplatelet agents'-ticagrelol and eptifibatide-safety in experimental colitis in mice

BACKGROUND/AIMS

To evaluate the side effects of two antiplatelet agents - ticagrelor and eptifibatide - in mice with experimentally-induced inflammatory bowel disease.

METHODS AND MATERIAL

This study was designed as a controlled, animal, drug safety investigation. C57Bl/6 mice were used to establish the ulcerative colitis model by exposure to dextran sulfate sodium (DSS), and divided into three experimental groups: eptifibatide-treated (150 µg/day intraperitoneally; n = 10), ticagrelol-treated (1 mg/day via gastric tube; n = 10), and DSS-control (plain drinking water; n = 10). An unmodeled non-DSS group served as the experimental control. Complete blood count was taken for all mice at baseline (day 0, treatment initiation) and after four days of treatment. On day 4, all animals were sacrificed for autopsy. The primary outcome measure was bleeding, and the secondary outcomes were change in platelet count, hemoglobin level, and hematocrit level.

RESULTS

Neither ticagrelor nor eptifibatide treatment produced a significant effect on DSS colitis mice for the safety parameters measured. Platelet count and hemoglobin and hematocrit levels were statistically similar between the three DSS groups and the non-DSS control group (P > 0.05). Autopsy found no evidence of recent bleeding in liver, spleen, central nervous system or serous cavities.

CONCLUSION

The antiplatelet agents ticagrelor and eptifibatide were safe in DSS colitis mice, suggesting their potential in humans suffering from ulcerative colitis, and supporting future safety studies.

Platelet factor 4 is a biomarker for lymphatic-promoted disorders

Genetic or acquired defects of the lymphatic vasculature often result in disfiguring, disabling, and, occasionally, life-threatening clinical consequences. Advanced forms of lymphedema are readily diagnosed clinically, but more subtle presentations often require invasive imaging or other technologies for a conclusive diagnosis. On the other hand, lipedema, a chronic lymphatic microvascular disease with pathological accumulation of subcutaneous adipose tissue, is often misdiagnosed as obesity or lymphedema; currently there are no biomarkers or imaging criteria available for a conclusive diagnosis. Recent evidence suggests that otherwise-asymptomatic defective lymphatic vasculature likely contributes to an array of other pathologies, including obesity, inflammatory bowel disease, and neurological disorders. Accordingly, identification of biomarkers of lymphatic malfunction will provide a valuable resource for the diagnosis and clinical differentiation of lymphedema, lipedema, obesity, and other potential lymphatic pathologies. In this paper, we profiled and compared blood plasma exosomes isolated from mouse models and from human subjects with and without symptomatic lymphatic pathologies. We identified platelet factor 4 (PF4/CXCL4) as a biomarker that could be used to diagnose lymphatic vasculature dysfunction. Furthermore, we determined that PF4 levels in circulating blood plasma exosomes were also elevated in patients with lipedema, supporting current claims arguing that at least some of the underlying attributes of this disease are also the consequence of lymphatic defects.

Evaluation of platelet count, erythrocyte sedimentation rate and C-reactive protein levels in paediatric patients with inflammatory and infectious disease

Inflammatory and infectious diseases are the major causes of morbidity and mortality. The identification of markers for the assessment of disease activity and response to treatment can improve long-term prognosis. The aim of this study was to evaluate platelet count, C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR) among children with inflammatory and infectious disease. This cross-sectional study was conducted in the paediatric immunology and infectious units of Shahid Madani Hospital of Khorramabad. One hundred fifty children, half boys and half girls, with diagnoses of infectious and inflammatory diseases were included in the study. Platelet count, ESR and CRP were measured at the time of hospitalization and thereafter (recovery phase). A questionnaire including demographic information, diagnosis and paraclinical data was completed. At the time of hospitalization, all 150 children had abnormal ESR, 110 (73.3%) had abnormal CRP and 12 (92%) had alterations in platelet count. At the time of discharge, one patient (0.7%) had normal ESR, 132 (88%) had normal CRP and 140 patients (93.3%) had normal platelet count. At the time of discharge, we found a significant difference between the levels of CRP and platelets in girls. This study showed that CRP level is useful during treatment follow-up. Changes in platelet count are likely to be more prevalent in girls.

Evaluation of Physiological Parameters of Intestinal Sulfate-Reducing Bacteria Isolated from Patients Suffering from IBD and Healthy People

BACKGROUND

Inflammatory bowel diseases (IBDs) are multifactorial illnesses of the intestine, to which microorganisms are contributing. Among the contributing microorganisms, sulfate-reducing bacteria (SRB) are suggested to be involved in the process of bowel inflammation due to the production of hydrogen sulfide (H2S) by dissimilatory sulfate reduction. The aims of our research were to physiologically examine SRB in fecal samples of patients with IBD and a control group, their identification, the study of the process of dissimilatory sulfate reduction (sulfate consumption and H2S production) and biomass accumulation. Determination of biogenic elements of the SRB and evaluation of obtained parameters by using statistical methods were also included in the research. The material for the research consisted of 14 fecal samples, which was obtained from patients and control subjects.

METHODS

Microscopic techniques, microbiological, biochemical, biophysical methods and statistical analysis were included.

RESULTS

Colonies of SRB were isolated from all the fecal samples, and subsequently, 35 strains were obtained. Vibrio-shaped cells stained Gram-negative were dominant in all purified studied strains. All strains had a high percentage of similarity by the 16S rRNA gene with deposited sequences in GenBank of Desulfovibrio vulgaris. Cluster analysis of sulfate reduction parameters allowed the grouping of SRB strains. Significant (p < 0.05) differences were not observed between healthy individuals and patients with IBD with regard to sulfate reduction parameters (sulfate consumption, H2S and biomass accumulation). Moreover, we found that manganese and iron contents in the cell extracts are higher among healthy individuals in comparison to unhealthy individuals that have an intestinal bowel disease, especially ulcerative colitis.

CONCLUSIONS

The observations obtained from studying SRB emphasize differences in the intestinal microbial processes of healthy and unhealthy people.

A novel and simple machine learning algorithm for preoperative diagnosis of acute appendicitis in children

INTRODUCTION

There is a tendency toward nonoperative management of appendicitis resulting in an increasing need for preoperative diagnosis and classification. For medical purposes, simple conceptual decision-making models that can learn are widely used. Decision trees are reliable and effective techniques which provide high classification accuracy. We tested if we could detect appendicitis and differentiate uncomplicated from complicated cases using machine learning algorithms.

MATERIALS AND METHODS

We analyzed all cases admitted between 2010 and 2016 that fell into the following categories: healthy controls (Group 1); sham controls (Group 2); sham disease (Group 3), and acute abdomen (Group 4). The latter group was further divided into four groups: false laparotomy; uncomplicated appendicitis; complicated appendicitis without abscess, and complicated appendicitis with abscess. Patients with comorbidities and whose complete blood count and/or pathology results were lacking were excluded. Data were collected for demographics, preoperative blood analysis, and postoperative diagnosis. Various machine learning algorithms were applied to detect appendicitis patients.

RESULTS

There were 7244 patients with a mean age of 6.84 ± 5.31 years, of whom 82.3% (5960/7244) were male. Most algorithms tested, especially linear methods, provided similar performance measures. We preferred the decision tree model due to its easier interpretability. With this algorithm, we detected appendicitis patients with 93.97% area under the curve (AUC), 94.69% accuracy, 93.55% sensitivity, and 96.55% specificity, and uncomplicated appendicitis with 79.47% AUC, 70.83% accuracy, 66.81% sensitivity, and 81.88% specificity.

CONCLUSIONS

Machine learning is a novel approach to prevent unnecessary operations and decrease the burden of appendicitis both for patients and health systems.

LEVELS OF EVIDENCE

III.

Diagnostic utility of the neutrophil-platelet ratio as a novel marker of activity in patients with Ulcerative Colitis

Background

Ulcerative colitis (UC) is a chronic disease characterized by periods of activity and remission. The platelet, one of the main activators of neutrophils, contains Interleukin 8 (IL-8), a potent neutrophil chemo-attractant and P-selectin that induces excretion of superoxide in the neutrophils, forming platelet-neutrophil aggregates that are increased in individuals with active UC, hence an index of both cells could produce a monitoring tool. No previous studies have evaluated this ratio in UC.

Goal

To evaluate the clinical utility of the Neutrophil-Platelet (NeuPla) ratio in patients with UC.

Study

A total of 158 patients with a diagnosis of UC. This index was based on the ratio between platelets and the neutrophil differential in blood count. The activity was classified using Mayo endoscopic sub-score, histological (Riley score) and for clinical was used the Truelove-Witts, Montreal, Mayo and Yamamoto-Furusho scores.

Results

The correlation of the NeuPla ratio with activity scales were significant (P <0.05). An optimal cut-off point to classify patients with clinical activity was 14.94 with a sensitivity 87.95% and specificity 63.5 and endoscopy activity with a cut-off 14.64 with a sensibility of 70.5% and specificity of 61.8%.

Conclusions

The NeuPla ratio showed an adequate diagnostic utility to identify UC patients with clinical and endoscopy activity without the use of invasive studies like a colonoscopy or expensive fecal biomarkers such as calprotectin and have a better diagnostic performance in comparison to other serum biomarkers (C reactive protein, erythrocyte sedimentation rate and albumin).

Platelets can reflect the severity of Crohn's disease without the effect of anemia

OBJECTIVES

Anemia and changes in platelets (PLT) are common in inflammatory bowel disease (IBD). In our study, we aimed to verify whether PLT count can independently reflect the severity of IBD.

METHODS

In our hospital, 137 Crohn's Disease (CD), 69 Ulcerative colitis (UC) patients, and 412 healthy controls were included to compare the differences in PLT count. In addition, the effect of anemia, C-reactive protein (CRP), age, CD activity index (CDAI) or Mayo on PLTs was also analyzed. If PLTs independently affected CD or UC, we used the receiver operating characteristic (ROC) curve to verify the diagnostic value and obtain the cut-off value of PLT.

RESULTS

CD and UC patients had higher PLT than controls (p<0.001, p<0.001; respectively). In CD patients, the results showed that patients with anemia (P<0.01), Iron Deficiency Anemia (IDA) (p<0.001), CRP≥8 mg/L (p=0.046), and CDAI≥150 (p<0.001) had higher PLT, while in UC patients, those with anemia (p=0.018), CRP≥8 mg/L (p=0.045), and Mayo≥3 (p=0.029) had higher PLT. Univariate analysis showed that CDAI was positively correlated with PLT count (p<0.001), while hemoglobin (p=0.001) and age (p<0.001) were negatively correlated with PLT in CD. In UC patients, Mayo (p=0.001) and CRP (p<0.001) were positively correlated with PLT, while hemoglobin (p=0.002) was negatively correlated. Finally, by linear stepwise multivariate analysis, we clarified the positive relationship between PLT and CD (p<0.001) by eliminating the interference of hemoglobin, and determined the cut-off value of PLT as 298×109/L. For UC, we did not obtain similar results.

CONCLUSIONS

PLT can be an indicator of disease severity in CD, while there is a lack of evidence regarding this finding in UC.

Platelet hyaluronidase-2 regulates the early stages of inflammatory disease in colitis

Platelets are specialized cells essential for hemostasis that also function as crucial effectors capable of mediating inflammatory and immune responses. These sentinels continually survey their environment and discriminate between homeostatic and danger signals such as modified components of the extracellular matrix. The glycosaminoglycan hyaluronan (HA) is a major extracellular matrix component that coats the vascular lumen and, under normal conditions, restricts access of inflammatory cells. In response to tissue damage, the endothelial HA matrix enhances leukocyte recruitment and regulates the early stages of the inflammatory response. We have shown that platelets can degrade HA from the surface of activated endothelial cells via the enzyme hyaluronidase-2 (HYAL2) and that HYAL2 is deficient in platelets isolated from patients with inflammatory bowel disease (IBD). Platelets are known to be involved in the pathogenesis of several chronic disease states, including IBD, but they have been largely overlooked in the context of intestinal inflammation. We therefore wanted to define the mechanism by which platelet HYAL2 regulates the inflammatory response during colitis. In this study, we provide evidence that HA catabolism is disrupted in human intestinal microvascular endothelial cells isolated from patients with IBD. Furthermore, mice deficient in HYAL2 are more susceptible to an acute model of colitis, and this increased susceptibility is abrogated by transfusion of HYAL2-competent platelets. Finally, we show that platelets, via HYAL2-dependent degradation of endothelial HA, regulate the early stages of inflammation in colitis by limiting leukocyte extravasation.

Novel Leucocyte/Thrombocyte Apheresis for Induction of Steroid-Free Remission in Ulcerative Colitis: A Controlled Randomized Pilot Study

BACKGROUND AND AIMS

In active ulcerative colitis [UC] refractory to mesalazine, escalation to either steroids or immunosuppression is common practice. The efficacy and safety of alternative escalation therapy with a novel leukocyte apheresis device were studied.

METHODS

This was a prospective, randomized, controlled multicentre pilot study comparing leukocyte apheresis with prednisolone in refractory UC (disease activity index [DAI] ≥ 4 and ≤8). Group A received weekly apheresis over five consecutive weeks. Group P received oral prednisolone 40 mg/day tapered to 0 mg at week 6. The primary end point was steroid-free clinical remission [DAI ≤ 2] at week 12. Clinical response was also analysed.

RESULTS

Twenty-four patients were enrolled, 13 of whom were randomized into group A and 11 into group P. Clinical remission off steroids at week 12 was achieved in 3/12 patients [25.0%] with apheresis and 2/10 [20.0%] with prednisolone [p = 1.0]. The response rate after 12 weeks was 75.0% in group A and 50.0% in group P. Mean DAI scores improved in both treatment groups [p = 0.008]. C-reactive protein decreased from 6.0 ± 5.3 to 3.8 ± 3.7 mg/L at 12 weeks in group A and increased from 5.2 ± 6.0 to 6.3 ± 7.9 mg/mL in group P. Both treatments were well tolerated. No unexpected serious adverse events were seen in group A. In group P one symptomatic infection with Clostridium difficile occurred.

CONCLUSIONS

In patients with active UC refractory to mesalazine a novel leukocyte apheresis showed promising results. A comparison with prednisolone revealed similar therapeutic effectivity and excellent safety, providing the chance to escalate without systemic steroids.

The formyl peptide fMLF primes platelet activation and augments thrombus formation

Essentials The role of formyl peptide receptor 1 (FPR1) and its ligand, fMLF, in the regulation of platelet function, hemostasis, and thrombosis is largely unknown. Fpr1-deficient mice and selective inhibitors for FPR1 were used to investigate the function of fMLF and FPR1 in platelets. N-formyl-methionyl-leucyl-phenylalanine primes platelet activation and augments thrombus formation, mainly through FPR1 in platelets. Formyl peptide receptor 1 plays a pivotal role in the regulation of platelet function.

BACKGROUND

Formyl peptide receptors (FPRs) play pivotal roles in the regulation of innate immunity and host defense. The FPRs include three family members: FPR1, FPR2/ALX, and FPR3. The activation of FPR1 by its high-affinity ligand, N-formyl-methionyl-leucyl-phenylalanine (fMLF) (a bacterial chemoattractant peptide), triggers intracellular signaling in immune cells such as neutrophils and exacerbates inflammatory responses to accelerate the clearance of microbial infection. Notably, fMLF has been demonstrated to induce intracellular calcium mobilization and chemotaxis in platelets that are known to play significant roles in the regulation of innate immunity and inflammatory responses. Despite a plethora of research focused on the roles of FPR1 and its ligands such as fMLF on the modulation of immune responses, their impact on the regulation of hemostasis and thrombosis remains unexplored.

OBJECTIVE

To determine the effects of fMLF on the modulation of platelet reactivity, hemostasis, and thrombus formation.

METHODS

Selective inhibitors for FPR1 and Fpr1-deficient mice were used to determine the effects of fMLF and FPR1 on platelets using various platelet functional assays.

RESULTS

N-formyl-methionyl-leucyl-phenylalanine primes platelet activation through inducing distinctive functions and enhances thrombus formation under arterial flow conditions. Moreover, FPR1 regulates normal platelet function as its deficiency in mouse or blockade in human platelets using a pharmacological inhibitor resulted in diminished agonist-induced platelet activation.

CONCLUSION

Since FPR1 plays critical roles in numerous disease conditions, its influence on the modulation of platelet activation and thrombus formation may provide insights into the mechanisms that control platelet-mediated complications under diverse pathological settings.

Platelet-Specific Deletion of Cyclooxygenase-1 Ameliorates Dextran Sulfate Sodium-Induced Colitis in Mice

Inflammatory bowel disease (IBD) is associated with an increased risk for thromboembolism, platelet activation, and abnormalities in platelet number and size. In colitis, platelets can extravasate into the colonic interstitium. We generated a mouse with a specific deletion of cyclooxygenase (COX)-1 in megakaryocytes/platelets [(COX-1 conditional knockout (cKO)] to clarify the role of platelet activation in the development of inflammation and fibrosis in dextran sodium sulfate (DSS)-induced colitis. The disease activity index was assessed, and colonic specimens were evaluated for histologic features of epithelial barrier damage, inflammation, and fibrosis. Cocultures of platelets and myofibroblasts were performed. We found that the specific deletion of COX-1 in platelets, which recapitulated the human pharmacodynamics of low-dose aspirin, that is, suppression of platelet thromboxane (TX)A₂ production associated with substantial sparing of the systemic production of prostacyclin, resulted in milder symptoms of colitis, in the acute phase, and almost complete recovery from the disease after DSS withdrawal. Reduced colonic accumulation of macrophages and myofibroblasts and collagen deposition was found. Platelet-derived TXA₂ enhanced the ability of myofibroblasts to proliferate and migrate in vitro, and these effects were prevented by platelet COX-1 inhibition or antagonism of the TXA₂ receptor. Our findings allow a significant advance in the knowledge of the role of platelet-derived TXA₂ in the development of colitis and fibrosis in response to intestinal damage and provide the rationale to investigate the potential efficacy of the antiplatelet agent low-dose aspirin in limiting the inflammatory response and fibrosis associated with IBD. SIGNIFICANCE STATEMENT: Inflammatory bowel disease (IBD) is characterized by the development of a chronic inflammatory response, which can lead to intestinal fibrosis for which currently there is no medical treatment. Through the generation of a mouse with specific deletion of cyclooxygenase-1 in megakaryocytes/platelets, which recapitulates the human pharmacodynamics of low-dose aspirin, we demonstrate the important role of platelet-derived thromboxane A₂ in the development of experimental colitis and fibrosis, thus providing the rationale to investigate the potential efficacy of low-dose aspirin in limiting the inflammation and tissue damage associated with IBD.

Smart Model to Distinguish Crohn’s Disease from Ulcerative Colitis

Inflammatory bowel diseases (IBD) is a term referring to chronic and recurrent gastrointestinal disease. It includes Crohn’s disease (CD) and ulcerative colitis (UC). It is undeniable that presenting features may be unclear and do not enable differentiation between disease types. Therefore, additional information, obtained during the analysis, can definitely provide a potential way to differentiate between UC and CD. For that reason, finding the optimal logistic model for further analysis of collected medical data, is a main factor determining the further precisely defined decision class for each examined patient. In our study, 152 patients with CD or UC were included. The collected data concerned not only biochemical parameters of blood but also very subjective information, such as data from interviews. The built-in logistics model with very high precision was able to assign patients to the appropriate group (sensitivity = 0.84, specificity = 0.74, AUC = 0.93). This model indicates factors differentiating between CD and UC and indicated odds ratios calculated for significantly different variables in these two groups. All obtained parameters of the model were checked for statistically significant. The constructed model was able to be distinguish between ulcerative colitis and Crohn’s disease.

Can Platelet Indices Reduce Negative Appendectomy Rates?

Introduction

The role of whole blood count parameters in the diagnosis of diseases in which inflammatory processes play a role is one of the more frequently mentioned topics in the literature in recent years. Studies of acute appendicitis have also been carried out in this regard, but studies focused on platelet parameters are few and contradictory. We aimed to investigate the role of mean platelet volume (MPV) and platelet distribution width (PDW) in the diagnosis of acute appendicitis.

Materials and methods

We retrospectively screened the medical records of patients older than 15 years who had an appendectomy from January 2012 to January 2015 at a training hospital in Kocaeli, Turkey. Patients were divided into three groups according to their pathology results: non-appendicitis (Group 1), uncomplicated appendicitis (Group 2), and complicated appendicitis (Group 3). We calculated the sensitivity, specificity, positive and negative predictive values, the likelihood ratios in the diagnosis of appendicitis for white blood cell (WBC), neutrophil count, c-reactive protein (CRP), MPV, and PDW values were calculated.

Results

There were no significant differences in the MPV between Group 1 (n = 39; 7.89 ± 1.32 fL), Group 2 (n = 119; 7.80 ± 1.19 fL), and Group 3 (n = 89; 7.70 ± 0.80 fL; p = 0.141). Also, we found no significant differences in PDW between Group 1 (117.38% ± 1.17), Group 2 (17.17% ± 1.04), and Group 3 (17.12% ± 0.64; p = 0.228).

Conclusions

Only nine of the 208 patients whose pathology reports confirmed appendicitis had healthy values for both CRP and WBC. Many factors affect MPV and PDW. Therefore, platelet indices are not useful markers in diagnosing acute appendicitis.

Cardiovascular Manifestations of Inflammatory Bowel Disease: Pathogenesis, Diagnosis, and Preventive Strategies

Inflammatory bowel disease (IBD) refers to a group of chronic inflammatory diseases that targets mainly the gastrointestinal tract. The clinical presentation of IBD includes both gastrointestinal manifestations and extraintestinal manifestations (EIM). The reported cardiovascular manifestations in IBD patients include pericarditis, myocarditis, venous and arterial thromboembolism, arrhythmias, atrioventricular block, heart failure, endocarditis, valvulopathies, and Takayasu arteritis. The aim of this article is to review the available literature about the possible pathogenic mechanisms and determine preventive measures capable of reducing the incidence and severity of the cardiovascular manifestations. In IBD patients, the incidence of cardiovascular manifestations is low, but higher than that in the general population. Therefore, clinicians should pay attention to any new modification that might indicate cardiovascular involvement in IBD patients, and they should consider chronic inflammatory diseases in patients with cardiac conditions without an evident cause. Considering the role of inflammation in the development of cardiovascular manifestations, the management should include prevention of flares and maintenance of remission for as long as possible. Preventive measures should also include active screening and strict control of the cardiovascular risk factors in all IBD patients.

Management of elderly ulcerative colitis in Japan

Japan has the largest aging society, where many elderly people have intractable diseases including ulcerative colitis (UC). Along with the increasing total number of UC patients, the number of elderly UC patients has also been increasing and will continue to do so in the future. Although the clinical features and natural history of UC in the elderly have many similarities with UC in the non-elderly population, age-specific concerns including comorbidities, immunological dysfunction, and polypharmacy make the diagnosis and management of elderly UC challenging compared to UC in non-elderly patients. Based on increasing data related to elderly UC patients from Japan, as well as other countries, we reviewed the epidemiology, clinical course, differential diagnosis, management of comorbidities, surveillance, medical therapy, and surgery of UC in the elderly.

A Simple Noninvasive Score Predicts Disease Activity and Deep Remission in Ulcerative Colitis

Background

There is a need to use noninvasive markers in refining the management of ulcerative colitis to reduce the number of unnecessary colonoscopies, which facilitates the follow-up of activity and the response to treatment.

Aim

Postulation of a sensitive, specific, simple and noninvasive score to monitor disease activity in ulcerative colitis.

Methods

A case-control study was conducted: 168 patients with ulcerative colitis, 40 healthy individuals, and 60 patients for validation. Patients were divided into new diagnosis (n = 50), clinical remission (n = 60), and relapse (n = 58). The main outcome measures if the score correlates with clinical, endoscopic and histopathological characteristics and if it correlates with deep remission.

Results

A scoring system was established composed of lactoferrin at a cutoff of 148.5 μg/mL, neutrophil lymphocyte ratio at a cutoff of 2.35, erythrocyte sedimentation rate at the first hour at a cutoff of 29.5 mm/h, C-reactive protein at a cutoff of 3.85 mg/L, mean platelet volume at a cutoff of 8.8 fL, fecal white blood cells at a cutoff of 9 cells/HPF, and fecal red blood cells at a cutoff of 6 cells/HPF. A score ≥5 can detect 94% of cases of UC as determined by the receiver operating characteristic curve with a sensitivity of 94% and a specificity 100%, AUC 0.92, SE 0.05, p = 0.001, 95% CI 0.82-1.1. In the validation group, it identified severely affected patients with a sensitivity of 95% and a specificity of 85.7%.

Conclusions

This easily applied and reproducible noninvasive activity score showed high performance in predicting disease activity and deep remission in ulcerative colitis.

Diagnostic Markers for Nonspecific Inflammatory Bowel Diseases

The nonspecific inflammatory bowel diseases (IBD) represent a heterogeneous group of chronic inflammatory disorders of the gastrointestinal tract, and Leśniowski-Crohn's disease (CD) and ulcerative colitis (UC) are among the two major clinical forms. Despite the great progress in understanding the pathogenesis of these diseases, their etiology remains unclear. Genetic, immune, and environmental factors are thought to play a key role. The correct diagnosis of nonspecific inflammatory bowel diseases as well as the determination of disease activity, risk stratification, and prediction of response to therapy still relies on a multidisciplinary approach based on clinical, laboratory, endoscopic, and histologic examination. However, considerable effort has been devoted to the development of an accurate panel of noninvasive biomarkers that have increased diagnostic sensitivity and specificity. Laboratory biomarkers useful in differentiating IBD with functional disorders and in evaluating disease activity, prognosis, and treatment selection for IBD are presented in this study.

Mouse Platelet Ral GTPases Control P-Selectin Surface Expression, Regulating Platelet-Leukocyte Interaction

OBJECTIVE

RalA and RalB GTPases are important regulators of cell growth, cancer metastasis, and granule secretion. The purpose of this study was to determine the role of Ral GTPases in platelets with the use of platelet-specific gene-knockout mouse models.

APPROACH AND RESULTS

This study shows that platelets from double knockout mice, in which both GTPases have been deleted, show markedly diminished (≈85% reduction) P-selectin translocation to the surface membrane, suggesting a critical role in α-granule secretion. Surprisingly, however, there were only minor effects on stimulated release of soluble α- and δ-granule content, with no alteration in granule count, morphology, or content. In addition, their expression was not essential for platelet aggregation or thrombus formation. However, absence of surface P-selectin caused a marked reduction (≈70%) in platelet-leukocyte interactions in blood from RalAB double knockout mice, suggesting a role for platelet Rals in platelet-mediated inflammation.

CONCLUSIONS

Platelet Ral GTPases primarily control P-selectin surface expression, in turn regulating platelet-leukocyte interaction. Ral GTPases could therefore be important novel targets for the selective control of platelet-mediated immune cell recruitment and inflammatory disease.