Exploring the Diagnostic Spectrum of Children with Raised Faecal Calprotectin Levels

Faecal calprotectin (FC) is a marker of gut inflammation. The cause and relevance of raised FC in children outside the context of established inflammatory bowel disease (IBD) have had minimal attention. This study aimed to address this by carrying out a retrospective study on children with abnormal FC tests aged 4-17 years without established IBD in the South Island, New Zealand. Abnormal FC results were stratified: 51-249 μg/g, 250-499 μg/g, and 500+ μg/g, and participants were categorised into diagnostic groups. Data were collected on symptoms and diagnostic tests. Three-hundred and ten children had abnormal index FC results, with a mean age of 12.9 years, and a 55% proportion of females. The median FC was 125 μg/g; 71% had levels 51-249 μg/g and 21% had levels 500+ μg/g. Of those with FC 500+ μg/g, 89% either had infectious diarrhoea or were diagnosed with IBD at the time of, or subsequent to, the index FC. Alarm symptoms did not delineate between groups with FC 500+ μg/g. Abnormalities in platelet levels, abdominal ultrasound, and colonoscopy were more frequent for children diagnosed with IBD. Repeat FC test levels were significantly reduced except for those subsequently diagnosed with IBD. Abnormal FC levels for the majority were below the level indicative of mucosal inflammation. Repeat FC testing could play an important role in distinguishing between diagnoses.

Calprotectin as a new inflammatory marker of abdominal aortic aneurysm: A pilot study

INTRODUCTION

Abdominal aortic aneurysm (AAA) is a relevant clinical problem due to the risk of rupture of progressively dilated infrarenal aorta. It is characterized by degradation of elastic fibers, extracellular matrix, and inflammation of the arterial wall. Though neutrophil infiltration is a known feature of AAA, markers of neutrophil activation are scarcely analyzed; hence, the main objective of this study.

METHODS

Plasma levels of main neutrophil activation markers were quantified in patients with AAA and a double control group (CTL) formed by healthy volunteers (HV) and patients with severe atherosclerosis submitted for carotid endarterectomy (CE). Calprotectin, a cytoplasmic neutrophil protein, was quantified, by Western blot, in arterial tissue samples from patients with AAA and organ donors. Colocalization of calprotectin and neutrophil elastase was assessed by immunofluorescence.

RESULTS

Plasma calprotectin and IL-6 were both elevated in patients with AAA compared with CTL (p ⩽ 0.0001) and a strong correlation was found between both molecules (p < 0.001). This difference was maintained when comparing with HV and CE for calprotectin but only with HV for IL-6. Calprotectin was also elevated in arterial tissue samples from patients with AAA compared with organ donors (p < 0.0001), and colocalized with neutrophils in the arterial wall.

CONCLUSIONS

Circulating calprotectin could be a specific AAA marker and a potential therapeutical target. Calprotectin is related to inflammation and neutrophil activation in arterial wall and independent of other atherosclerotic events.

Elevated NET, Calprotectin, and Neopterin Levels Discriminate between Disease Activity in COVID-19, as Evidenced by Need for Hospitalization among Patients in Northern Italy

Coronavirus disease 2019 (COVID-19) displays clinical heterogeneity, but little information is available for patients with mild or very early disease. We aimed to characterize biomarkers that are useful for discriminating the hospitalization risk in a COVID-19 cohort from Northern Italy during the first pandemic wave. We enrolled and followed for four weeks 76 symptomatic SARS-CoV-2 positive patients and age/sex-matched healthy controls. Patients with mild disease were discharged (n.42), and the remaining patients were hospitalized (n.34). Blood was collected before any anti-inflammatory/immunosuppressive therapy and assessed for soluble C5b-9/C5a, H3-neutrophil extracellular traps (NETs), calprotectin, and DNase plasma levels via ELISA and a panel of proinflammatory cytokines via ELLA. Calprotectin and NET levels discriminate between hospitalized and non-hospitalized patients, while DNase negatively correlates with NET levels; there are positive correlations between calprotectin and both NET and neopterin levels. Neopterin levels increase in patients at the beginning of the disease and do so more in hospitalized than non-hospitalized patients. C5a and sC5b-9, and other acute phase proteins, correlate with neopterin, calprotectin, and DNase. Both NET and neopterin levels negatively correlate with platelet count. We show that calprotectin, NETs, and neopterin are important proinflammatory parameters potentially useful for discriminating between COVID-19 patients at risk of hospitalization.

Low ALT Is Associated with IBD and Disease Activity: Results from a Nationwide Study

Background: Sarcopenia is underdiagnosed in patients with inflammatory bowel disease (IBD). Low alanine transaminase (ALT) is associated with sarcopenia. We evaluated the association between low ALT and the presence of IBD and disease activity. Methods: Data were collected from a national Israeli health insurer cohort comprising 976,615 patients. Patients with a diagnosis of IBD were compared to healthy controls. After exclusion of patients with liver disease, ALT > 40 IU/L and age < 18, a total of 233,451 patients were included in the analysis. Low ALT was defined as <10 IU/L. Results: Low ALT was more common amongst patients with IBD than in healthy controls (7.76% vs. 5.7% p < 0.001). Low ALT was found in 148 (7.9%) of the patients with CD and 69 (6.9%) of the patients with UC. For CD, low ALT was associated with increased fecal calprotectin (FC) and CRP (223.00 μg/mg [63.45-631.50] vs. 98.50 [31.98-324.00], p < 0.001, 9.10 mg/L [3.22-19.32] vs. 3.20 [1.30-8.30], p < 0.001) and decreased albumin and hemoglobin (3.90 g/dL [3.60-4.20] vs. 4.30 [4.00-4.50], p < 0.001,12.20 g/dL [11.47-13.00] vs. 13.60 [12.60-14.70], p < 0.001). For UC, low ALT was associated with higher FC and CRP (226.50 μg/mg [143.00-537.00] vs. 107.00 [40.85-499.50], p = 0.057, 4.50 mg/L [1.90-11.62] vs. 2.30 [1.00-6.20], p < 0.001) and with lower albumin and hemoglobin (4.00 g/dL [3.62-4.18] vs. 4.30 [4.10-4.40], p < 0.001, 12.40 g/dL [11.60-13.20] vs. 13.60 [12.60-14.60], p < 0.001). These findings remained consistent following multivariate regression and in a propensity score-matched cohort. Conclusions: Low ALT is more common in patients with IBD and is associated with biochemical disease activity indices.

Continuous Monitoring of CRP, IL-6, and Calprotectin in Inflammatory Bowel Disease Using a Perspiration-Based Wearable Device

BACKGROUND

Wearable sensor devices represent a noninvasive technology to continuously track biomarkers linked to inflammatory bowel disease (IBD). We assessed the inflammatory markers associated with IBD in human perspiration.

METHODS

Participants with IBD were monitored for 40 to 130 minutes with a proprietary wearable sensor device used to measure C-reactive protein, interleukin-6, and calprotectin. Sensor response using electrochemical impedance spectroscopy and serum samples were measured on the same day. The Mann-Whitney test was used to analyze the relationship between active and remission IBD in serum and perspiration, classified according to endoscopic reports and serum biomarker levels. Asynchronously collected fecal calprotectin from a subset of the population was similarly analyzed.

RESULTS

A total of 33 subjects were enrolled. Expression of calprotectin was significantly elevated in the active cohort compared with the remission cohort in perspiration (P < .05; median = 906.69 ng/mL; active 95% confidence interval [CI], 466.0-1833 ng/mL; remission 95% CI, 328.4-950.8 ng/mL), serum (median = 1860.82 ng/mL; active 95% CI, 1705-2985 ng/mL; remission 95% CI, 870.2-1786 ng/mL), and stool (P < .05; median = 126.74 µg/g; active 95% CI, 77.08-347.1 µg/g; remission 95% CI, 5.038-190.4 µg/g). Expression of CRP in perspiration and serum was comparable between the active and remission cohorts (perspiration: P > .05; median = 970.83 pg/mL; active 95% CI, 908.7-992 pg/mL; remission 95% CI, 903.3-991.9 pg/mL; serum: median = 2.34 µg/mL; active 95% CI, 1.267-4.492 µg/mL; remission 95% CI, 1.648-4.287 µg/mL). Expression of interleukin-6 in perspiration was nonsignificant in the active cohort compared with the remission cohort and was significantly elevated in serum (perspiration: P < .05; median = 2.13 pg/mL; active 95% CI, 2.124-2.44 pg/mL; remission 95% CI, 1.661-2.451 pg/mL; serum: median = 1.15 pg/mL; active 95% CI, 1.549-3.964 pg/mL; remission 95% CI, 0.4301-1.257 pg/mL). Analysis of the linear relationship between perspiration and serum calprotectin (R2 = 0.7195), C-reactive protein (R2 = 0.615), and interleukin-6 (R2 = 0.5411) demonstrated a strong to moderate relationship across mediums.

CONCLUSIONS

We demonstrate the clinical utility of perspiration as a noninvasive medium for continuous measurement of inflammatory markers in IBD and find that the measures correlate with serum and stool markers across a range of disease activity.

The association between drugs and repeated treatment with budesonide in patients with microscopic colitis: a retrospective observational study

Background

Smoking and the use of non-steroidal anti-inflammatory drugs (NSAIDs) acetylsalicylic acid (ASA), proton pump inhibitors (PPIs), serotonin reuptake inhibitors (SSRIs), and statins have been associated with microscopic colitis (MC).

Objectives

We investigated whether these factors were associated with repeated budesonide treatments in patients diagnosed with MC.

Design

Retrospective observational study.

Methods

All patients with a histologically verified diagnosis of MC at our clinic between the years 2006 and 2022 were identified. Baseline factors and drugs prescribed before and after diagnosis were registered. The influence of risk factors on the odds of having a prescription of oral budesonide and the odds of having a second course of budesonide was studied.

Results

Patients with MC (n = 183) with a mean age of 62.3 years [standard deviation (SD): 13.3 years] were followed for a median of 5 years (25th-75th percentile 4-10 years) after diagnosis. In all, 138 patients (75%) had at least one prescription of budesonide after diagnosis, and 90 patients (49%) had at least one clinical relapse treated with budesonide. Patients who had been prescribed NSAIDs within 1 year before clinical relapse had higher odds for clinical relapse [odds ratio (OR): 3.70, 95% confidence interval (CI): 1.06-12.9] but there was no increased risk for clinical relapse for the use of ASA (OR: 0.99, 95% CI: 0.39-2.90), PPIs (OR: 1.09, 95% CI: 0.45-2.63), SSRI (OR: 1.41, 95% CI: 0.82-2.44), or statins (OR: 0.83, 95% CI: 0.35-1.99). No association was seen between being a smoker and/or being prescribed NSAID, ASA, PPI, SSRI, and statins at baseline and the odds of having a prescription of oral budesonide within 1 year after diagnosis.

Conclusion

The risk of being prescribed a second course of budesonide is associated with receiving a prescription of NSAIDs but not with the use of ASA, PPIs, SSRIs, and statins.

Plasma calprotectin and new-onset type 2 diabetes in the general population: a prospective cohort study

BACKGROUND

Systemic inflammation plays a pivotal role in the development of type 2 diabetes (T2D). Here we hypothesized that circulating levels of calprotectin, a myeloid cell-derived biomarker of inflammation, is associated with the development of new-onset T2D in the general population.

METHODS

A total of 4,815 initially non-diabetic participants of the Prevention of Renal and Vascular ENd-stage Disease (PREVEND), a prospective population-based cohort study, were assessed for plasma levels of calprotectin at baseline. Circulating levels of calprotectin were investigated for potential associations with the risk of new-onset T2D, defined as a fasting plasma glucose level ≥7.0 mmol/l, a random plasma glucose level ≥11.1 mmol/l, a self-reported physician-based diagnosis of T2D, the use of glucose-lowering drugs, or any combinations thereof.

RESULTS

Median plasma calprotectin levels were 0.49 [0.35-0.69] mg/l. Plasma calprotectin levels were significantly associated with the risk of new-onset T2D (hazard ratio [HR] per doubling 1.42 [95% confidence interval: 1.22-1.66], P<0.001). The association remained independent of adjustment for age and sex (HR 1.34 [95%CI: 1.14-1.57], P<0.001), but not after further adjustment for potentially confounding factors (HR 1.11 [95% CI: 0.90-1.37], P=0.326), with adjustment for hyperlipidemia and high-sensitivity C-reactive protein explaining the loss of significance. Stratified analyses showed significant effect modification by hypertension, history of cardiovascular disease and HOMA-IR (Pinteraction≤0.001 for each), with higher HRs in individuals without hypertension, without history of cardiovascular disease and with below-median HOMA-IR.

CONCLUSIONS

Elevated plasma levels of calprotectin are associated with a higher risk of developing T2D in the general population and may represent a moveable inflammatory biomarker. This association, however, does not represent a direct effect, and seems dependent on hyperlipidemia and systemic inflammation.

Do Alarmins Have a Role in Multiple Myeloma?

Objective

Calprotectin (CLP), S100A6, and High Mobility Group Nucleosome-Binding Protein 1 (HMGN1), known as alarmins, are involved in the pathogenesis of many tumors. In this study, we aimed to inve stigate the relationship of serum CLP, S100A6, and HMGN1 levels with clinical and laboratory findings in Multiple Myeloma (MM) patients and their role in the pathogenesis of MM.

Materials and Methods

We measured serum CLP, S100A6, and HMGN1 levels in 55 newly diagnosed patients and 32 healthy controls (HC).

Results

We determined significantly decreased serum CLP, S100A6 ve HMGN1 levels in MM patients compared to HC (p=0.012, p=0.001, p=0.030, respectively). ROC analysis was used to determine a diagnostic cut-off value for serum CLP, S100A6 and HMGN1; the cut off value for CLP was <98 ng/ml (AUC = 0.663, 95% CI 0.554-0.761, p=0.009), S100A6 was <1174.5 pg/ml (AUC = 0.706, 95% CI 0.598-0.799, p=0.001), and HMGN1 was <440.18 pg/ml (AUC = 0.640, 95% CI 0.530-0.740, p:0.03). CLP level was found to be statistically significantly in light chain MM patients ( 91.58±22.57) higher than in heavy chain MM patients (79.42±15.83) (p=0.03). A negative correlation was observed between CLP and M protein, IgG, globulin, and beta 2 microglobulin (correlation coefficient: -0,361; -0,370; -0,279; -0,300, p=0,024, p=006, p=0,04, p=0,0033).

Conclusion

In this study, we found that serum CLP, S100A6, and HMGN1 levels were statistically lower in newly diagnosed MM patients compared to HC. These results suggest that CLP may binds to the paraprotein produced by heavy chain MM in the blood and therefore its blood levels are found to be low. Additionally, low levels of HMGN1, which is involved in DNA repair, suggest that HMGN1 may contribute to the complex genetic abnormalities found in MM.

Elevated level of circulating calprotectin correlates with severity and high mortality in patients with COVID-19

BACKGROUND

Patients with coronavirus disease-2019 (COVID-19) are characterized by hyperinflammation. Calprotectin (S100A8/S100A9) is a calcium- and zinc-binding protein mainly secreted by neutrophilic granulocytes or macrophages and has been suggested to be correlated with the severity and prognosis of COVID-19.

AIM

To thoroughly evaluate the diagnostic and prognostic utility of calprotectin in patients with COVID-19 by analyzing relevant studies.

METHODS

PubMed, Web of Science, and Cochrane Library were comprehensively searched from inception to August 1, 2023 to retrieve studies about the application of calprotectin in COVID-19. Useful data such as the level of calprotectin in different groups and the diagnostic efficacy of this biomarker for severe COVID-19 were extracted and aggregated by using Stata 16.0 software.

RESULTS

Fifteen studies were brought into this meta-analysis. First, the pooled standardized mean differences (SMDs) were used to estimate the differences in the levels of circulating calprotectin between patients with severe and non-severe COVID-19. The results showed an overall estimate of 1.84 (95% confidence interval [CI]: 1.09-2.60). Diagnostic information was extracted from 11 studies, and the pooled sensitivity and specificity of calprotectin for diagnosing severe COVID-19 were 0.75 (95% CI: 0.64-0.84) and 0.88 (95% CI: 0.79-0.94), respectively. The AUC was 0.89 and the pooled DOR was 18.44 (95% CI: 9.07-37.51). Furthermore, there was a strong correlation between elevated levels of circulating calprotectin and a higher risk of mortality outcomes in COVID-19 patients (odds ratio: 8.60, 95% CI: 2.17-34.12; p < 0.1).

CONCLUSION

This meta-analysis showed that calprotectin was elevated in patients with severe COVID-19, and this atypical inflammatory cytokine might serve as a useful biomarker to distinguish the severity of COVID-19 and predict the prognosis.

Fecal dysbiosis and inflammation in intestinal-specific Cftr knockout mice on regimens preventing intestinal obstruction

Chronic intestinal inflammation is a poorly understood manifestation of cystic fibrosis (CF), which may be refractory to ion channel CF transmembrane conductance regulator (CFTR) modulator therapy. People with CF exhibit intestinal dysbiosis, which has the potential for stimulating intestinal and systemic inflammation. CFTR is expressed in organ epithelia, leukocytes, and other tissues. Here, we investigate the contribution of intestinal epithelium-specific loss of Cftr [iCftr knockout (KO)] to dysbiosis and inflammation in mice treated with either of two antiobstructive dietary regimens necessary to maintain CF mouse models [polyethylene glycol (PEG) laxative or a liquid diet (LiqD)]. Feces collected from iCftr KO mice and their wild-type (WT) sex-matched littermates were used to measure fecal calprotectin to evaluate inflammation and to perform 16S rRNA sequencing to characterize the gut microbiome. Fecal calprotectin was elevated in iCftr KO relative to WT mice that consumed either PEG or LiqD. PEG iCftr KO mice did not show a change in α diversity versus WT mice but demonstrated a significant difference in microbial composition (β diversity) with included increases in the phylum Proteobacteria, the family Peptostreptococcaceae, four genera of Clostridia including C. innocuum, and the mucolytic genus Akkermansia. Fecal microbiome analysis of LiqD-fed iCftr KO mice showed both decreased α diversity and differences in microbial composition with increases in the Proteobacteria family Enterobacteriaceae, Firmicutes families Clostridiaceae and Peptostreptococcaceae, and enrichment of Clostridium perfringens, C. innocuum, C. difficile, mucolytic Ruminococcus gnavus, and reduction of Akkermansia. It was concluded that epithelium-specific loss of Cftr is a major driver of CF intestinal dysbiosis and inflammation with significant similarities to previous studies of pan Cftr KO mice.NEW & NOTEWORTHY Chronic intestinal inflammation is a manifestation of cystic fibrosis (CF), a disease caused by loss of the anion channel CF transmembrane conductance regulator (CFTR) that is expressed in many tissues. This study shows that intestinal epithelial cell-specific loss of CFTR [inducible Cftr knockout (KO)] in mice is sufficient to induce intestinal dysbiosis and inflammation. Experiments were performed on mice consuming two dietary regimens routinely used to prevent obstruction in CF mice.

Plasma NGAL levels in stable kidney transplant recipients and the risk of allograft loss

BACKGROUND

The objective of this study was to investigate the utility of neutrophil gelatinase-associated lipocalin (NGAL) and calprotectin (CPT) to predict long-term graft survival in stable kidney transplant recipients (KTR).

METHODS

A total of 709 stable outpatient KTR were enrolled >2 months post-transplant. The utility of plasma and urinary NGAL (pNGAL, uNGAL) and plasma and urinary CPT at enrollment to predict death-censored graft loss was evaluated during a 58-month follow-up.

RESULTS

Among biomarkers, pNGAL showed the best predictive ability for graft loss and was the only biomarker with an area under the curve (AUC) > 0.7 for graft loss within 5 years. Patients with graft loss within 5 years (n = 49) had a median pNGAL of 304 [interquartile range (IQR) 235-358] versus 182 (IQR 128-246) ng/mL with surviving grafts (P < .001). Time-dependent receiver operating characteristic analyses at 58 months indicated an AUC for pNGAL of 0.795, serum creatinine-based Chronic Kidney Disease Epidemiology Collaboration estimated glomerular filtration rate (eGFR) had an AUC of 0.866. pNGAL added to a model based on conventional risk factors for graft loss with death as competing risk (age, transplant age, presence of donor-specific antibodies, presence of proteinuria, history of delayed graft function) had a strong independent association with graft loss {subdistribution hazard ratio (sHR) for binary log-transformed pNGAL [log2(pNGAL)] 3.4, 95% confidence interval (CI) 2.24-5.15, P < .0001}. This association was substantially attenuated when eGFR was added to the model [sHR for log2(pNGAL) 1.63, 95% CI 0.92-2.88, P = .095]. Category-free net reclassification improvement of a risk model including log2(pNGAL) in addition to conventional risk factors and eGFR was 54.3% (95% CI 9.2%-99.3%) but C-statistic did not improve significantly.

CONCLUSIONS

pNGAL was an independent predictor of renal allograft loss in stable KTR from one transplant center but did not show consistent added value when compared with baseline predictors including the conventional marker eGFR. Future studies in larger cohorts are warranted.

Trends in Faecal Zonulin Concentrations in Paediatric Patients with Celiac Disease at Baseline and on a Gluten-Free Diet: Exploring Correlations with Other Faecal Biomarkers

Celiac disease (CeD) is an autoimmune condition triggered by gluten in genetically predisposed individuals, affecting all ages. Intestinal permeability (IP) is crucial in the pathogenesis of CeD and it is primarily governed by tight junctions (TJs) that uphold the intestinal barrier's integrity. The protein zonulin plays a critical role in modulating the permeability of TJs having emerged as a potential non-invasive biomarker to study IP. The importance of this study lies in providing evidence for the usefulness of a non-invasive tool in the study of IP both at baseline and in the follow-up of paediatric patients with CeD. In this single-centre prospective observational study, we explored the correlation between faecal zonulin levels and others faecal and serum biomarkers for monitoring IP in CeD within the paediatric population. We also aimed to establish reference values for faecal zonulin in the paediatric population. We found that faecal zonulin and calprotectin values are higher at the onset of CeD compared with the control population. Specifically, the zonulin levels were 347.5 ng/mL as opposed to 177.7 ng/mL in the control population (p = 0.001), while calprotectin levels were 29.8 μg/g stool compared to 13.9 μg/g stool (p = 0.029). As the duration without gluten consumption increased, a significant reduction in faecal zonulin levels was observed in patients with CeD (348.5 ng/mL vs. 157.1 ng/mL; p = 0.002), along with a decrease in the prevalence of patients with vitamin D insufficiency (88.9% vs. 77.8%). We conclude that faecal zonulin concentrations were higher in the patients with active CeD compared with healthy individuals or those following a gluten-free diet (GFD). The significant decrease in their values over the duration of the GFD suggests the potential use of zonulin as an additional tool in monitoring adherence to a GFD.

The drug-survival of low-dose thioguanine in patients with inflammatory bowel disease: a retrospective observational study

Background

Thiopurines are commonly used to treat inflammatory bowel disease but withdrawal due to side effects are common. Thioguanine has been suggested to be better tolerated than conventional thiopurines.

Objectives

We studied drug-survival of low dose of thioguanine in real-life clinical practice in comparison to conventional thiopurines.

Design

Retrospective observational study.

Methods

All patients born 1956 and later, and who at least once started thiopurine treatment between 2006 and 2022 were included. A medical chart review was performed that noted drug-survival for every thiopurine treatment attempt. The Mantel-Cox rank test was used to test differences in drug-survival for different thiopurines. Blood chemistry analysis and faecal calprotectin levels were registered for the first 5 years of treatment.

Results

In the study population, there was 379 initiated thiopurine treatments (210 for Crohn's disease and 169 for ulcerative colitis) in 307 patients with inflammatory bowel disease (IBD). Low-dose thioguanine (median dose 11 mg; 25-75th percentile 7-19 mg) had been initiated in 31 patients. Overall, when including all thiopurine attempts, thioguanine had the longest drug-survival [Mantel-Cox rank test: thioguanine versus azathioprine p = 0.014; thioguanine versus 6-mercaptopurine (6-MP) p < 0.001]. For second-line thiopurine treatment thioguanine had longer drug-survival than 6-MP (Mantel-Cox rank test: p = 0.006). At 60 months, 86% of the patients who started low-dose thioguanine were still on treatment compared to 42% of the patients who started 6-MP (p = 0.022). The median 6-thioguanine nucleotide levels in patients treated with thioguanine was 364 pmol/8 × 108. Patients on thioguanine treatment showed significantly lower values of median mean corpuscular volume at follow-up than patients treated with azathioprine and 6-MP. Patients treated with 6-MP showed significantly lower levels of FC in the third year of treatment compared to patient treated with azathioprine (59 versus 109 µg/g; p = 0.023), but there was no significant difference in FC levels for thioguanine compared to azathioprine (50 versus 109 µg/g; p = 0.33).

Conclusion

Treatment with a low dose of thioguanine is well-tolerated in patients with IBD and had a significantly higher drug-survival than conventional thiopurines.

Measurement of Calprotectin and PTH in the Amniotic Fluid of Early Second Trimester Pregnancies and Their Impact on Fetuses with Growth Disorders: Are Their Levels Related to Oxidative Stress?

Background: During the early stages of human fetal development, the fetal skeleton system is chiefly made up of cartilage, which is gradually replaced by bone. Fetal bone development is mainly regulated by the parathyroid hormone parathormone (PTH) and PTH-related protein, with specific calprotectin playing a substantial role in cell adhesion and chemotaxis while exhibiting antimicrobial activity during the inflammatory osteogenesis process. The aim of our study was to measure the levels of PTH and calprotectin in early second trimester amniotic fluid and to carry out a comparison between the levels observed among normal full-term pregnancies (control group) and those of the groups of embryos exhibiting impaired or enhanced growth. Methods: For the present prospective study, we collected amniotic fluid samples from pregnancies that underwent amniocentesis at 15 to 22 weeks of gestational age during the period 2021-2023. Subsequently, we followed up on all pregnancies closely until delivery. Having recorded fetal birthweights, we then divided the neonates into three groups: small for gestational age (SGA), appropriate for gestational age (AGA), and large for gestational age (LGA). Results: In total, 64 pregnancies, including 14 SGA, 10 LGA, and 40 AGA fetuses, were included in our study. Both substances were detected in early second trimester amniotic fluid in both groups. Concentrations of calprotectin differed significantly among the three groups (p = 0.033). AGA fetuses had a lower mean value of 4.195 (2.415-6.425) IU/mL, whereas LGA fetuses had a higher mean value of 6.055 (4.887-13.950) IU/mL, while SGA fetuses had a mean value of 5.475 (3.400-9.177) IU/mL. Further analysis revealed that only LGA fetuses had significantly higher calprotectin concentrations compared to AGA fetuses (p = 0.018). PTH concentration was similar between the groups, with LGA fetuses having a mean value of 13.18 (9.51-15.52) IU/mL, while SGA fetuses had a mean value of 14.18 (9.02-16.00) IU/mL, and AGA fetuses had similar concentrations of 13.35 (9.05-15.81) IU/mL. The differences in PTH concentration among the three groups were not statistically significant (p = 0.513). Conclusions: Calprotectin values in the amniotic fluid in the early second trimester were higher in LGA fetuses compared to those in the SGA and AGA categories. LGA fetuses can possibly be in a state of low-grade chronic inflammation due to excessive fat deposition, causing oxidative stress in LGA fetuses and, eventually, the release of calprotectin. Moreover, PTH concentrations in the amniotic fluid of early second trimester pregnancies were not found to be statistically correlated with fetal growth abnormalities in either LGA or SGA fetuses. However, the early time of collection and the small number of patients in our study should be taken into account.

Systematic review of the role of calprotectin in cirrhosis

BACKGROUND

Calprotectin is a calcium-binding-S100-protein synthetized mainly in neutrophils which has been demonstrated to be an accurate biomarker of the presence of these cells. Gut barrier dysfunction in patients with advanced chronic liver disease (ACLD), in addition to the lack of noninvasive tools for diagnosis and prognosis of cirrhosis decompensations, has raised interest in this biomarker.

AIMS

Our aim is to summarize the current evidence regarding the role of calprotectin in terms of its diagnostic and prognostic utility in ACLD.

METHODS

We performed a systematic search (PROSPERO registration no. CRD42023389069) of original articles published without any restrictions on the publication date until January 2023 providing information about calprotectin for the prognosis or diagnosis of ACLD and its decompensations in adult patients.

RESULTS

A total 227 articles were identified, and 26 observational studies finally met the inclusion criteria. In 14 studies, calprotectin was measured in ascitic fluid, all of which reported higher calprotectin values in spontaneous bacterial peritonitis, while cut-off points for its diagnosis were proposed in nine studies. Three studies reported higher faecal calprotectin levels in patients with hepatic encephalopathy and portal hypertension. Four studies evaluated faecal calprotectin and one plasma calprotectin as biomarkers for gut barrier integrity and bacterial translocation.

CONCLUSIONS

Calprotectin is emerging as a promising biomarker in ACLD, particularly for the management of bacterial infections and alcohol-related liver disease. Further research with better study designs should help to determine the feasibility of calprotectin measurement in routine clinical practice.

Plasma Calprotectin Levels Associate With New-Onset Hypertension in the General Population: A Prospective Cohort Study

BACKGROUND

Low-grade systemic inflammation is a relevant pathogenic mechanism underlying the development of hypertension. In this study, we hypothesized that plasma calprotectin levels, as a biomarker of neutrophil-mediated inflammation, is associated with developing new-onset hypertension in the general population.

METHODS AND RESULTS

Plasma calprotectin levels were determined in 3524 participants who participated in the PREVEND (Prevention of Renal and Vascular End-Stage Disease) study, a prospective population-based cohort study. Plasma calprotectin levels were studied for associations with the risk of new-onset hypertension, defined as systolic blood pressure of at least 140 mm Hg, diastolic blood pressure of at least 90 mm Hg, or the first recorded use of antihypertensives. Participants with hypertension at baseline were excluded. Median plasma calprotectin levels were 0.48 (0.34-0.66) mg/L, and median systolic blood pressure was 117 (109-126) mm Hg. Plasma calprotectin levels were significantly associated with the risk of new-onset hypertension (hazard ratio [HR], per doubling 1.30 [95% CI, 1.21-1.41]; P<0.001), also after adjustment for age and sex (HR, 1.26 [95% CI, 1.16-1.37]; P<0.001), but not after additional adjustment for potentially confounding factors, including baseline systolic blood pressure (HR, 1.00 [95% CI, 0.90-1.11]; P=0.996). Stratified analyses showed significant effect modification by sex (Pinteraction=0.023) and urinary albumin excretion (Pinteraction=0.004), with higher HRs in men (compared with women) and in individuals with higher urinary albumin excretion (>9.3 mg per 24 hours) compared with lower urinary albumin excretion (≤9.3 mg per 24 hours).

CONCLUSIONS

Higher plasma calprotectin levels are associated with an increased risk of new-onset hypertension in the general population. This association is dependent on baseline systolic blood pressure and is particularly prominent in men compared with women.

Pathogen-specific alterations in intestinal microbiota precede urinary tract infections in preterm infants: a longitudinal case-control study

Urinary tract infections (UTIs) are among the most common late-onset infections in preterm infants, characterized by nonspecific symptoms and a pathogenic spectrum that diverges from that of term infants and older children, which present unique diagnostic and therapeutic challenges. Existing data on the role of gut microbiota in UTI pathogenesis in this demographic are limited. This study aims to investigate alterations in gut microbiota and fecal calprotectin levels and their association with the development of UTIs in hospitalized preterm infants. A longitudinal case-control study was conducted involving preterm infants admitted between January 2018 and October 2020. Fecal samples were collected weekly and analyzed for microbial profiles and calprotectin levels. Propensity score matching, accounting for key perinatal factors including age and antibiotic use, was utilized to match samples from UTI-diagnosed infants to those from non-UTI counterparts. Among the 151 preterm infants studied, 53 were diagnosed with a UTI, predominantly caused by Enterobacteriaceae (79.3%) and Enterococcaceae (19.0%). Infants with UTIs showed a significantly higher abundance of these families compared to non-UTI infants, for both Gram-negative and positive pathogens, respectively. Notably, there was a significant pre-UTI increase in the abundance of pathogen-specific taxa in infants later diagnosed with UTIs, offering high predictive value for early detection. Shotgun metagenomic sequencing further confirmed the dominance of specific pathogenic species pre-UTI and revealed altered virulence factor profiles associated with Klebsiella aerogenes and Escherichia coli infections. Additionally, a decline in fecal calprotectin levels was observed preceding UTI onset, particularly in cases involving Enterobacteriaceae. The observed pathogen-specific alterations in the gut microbiota preceding UTI onset offer novel insight into the UTI pathogenesis and promising early biomarkers for UTIs in preterm infants, potentially enhancing the timely management of this common infection. However, further validation in larger cohorts is essential to confirm these findings.

Characteristics of fecal calprotectin as an early marker for suspected necrotizing enterocolitis in newborns exclusively fed maternal breast milk: a case-control study

Objective

Numerous studies have proposed using fecal calprotectin among many biomarkers associated with necrotizing enterocolitis (NEC) diagnosis. This study aimed to evaluate fecal calprotectin as an early marker for suspected NEC (stage 1) in infants fed exclusively breast milk.

Methods

We collected 20 stool samples from newborns admitted to the neonatal intensive care unit at Aswan University Hospital diagnosed with stage I NEC. We compared them with 20 samples from matched healthy newborns. Fecal calprotectin level was measured by enzyme-linked immunosorbent assay.

Results

Fecal calprotectin level was higher in cases than in the control group (P < 0.001). Also, there was a positive correlation between fecal calprotectin and C-reactive protein in the studied cases (P = 0.001). However, there were no correlations between fecal calprotectin and sex or postnatal age.

Conclusion

Fecal calprotectin levels increase in newborns with stage I NEC. Although not specific, its sensitivity suggests a role as a potential biomarker in the evaluation of suspected NEC.

The Association of Serum Calprotectin with Fitness Indicators and Biochemical Markers in High-Level Athletes: A Continuous Dynamic Monitoring during One Competitive Season

The objective was to determine the associations between several biochemical indicators and the dynamics of concentration change across four physical fitness phases over the period of a competitive season. Furthermore, associations between serum calprotectin and biomarkers of inflammation or muscle injury and physical indicators were examined.

SUBJECTS AND METHODS

Twenty professional male water polo players (median age: 28 (22-42)) were included in this study. Serum creatine kinase activity was determined by the automated photometric UV method. The concentrations of calprotectin, C-reactive protein, and myoglobin were measured using an automated immunoturbidimetric method, while an automated immunochemistry method was employed for interleukin-6, troponin I, and cortisol determination. Tests of repeated strength, maximal strength, and static strength were used to evaluate physical activity.

RESULTS

Serum calprotectin concentrations expressed in median and IQR were significantly different: T1: 2.92 g/mL (2.47; 3.86); T2: 2.35 g/mL (1.26; 2.87); T3: 2.27 g/mL (1.60; 3.27); and T4: 1.47 g/mL (1.04; 2.85) (p = 0.004). Cortisol concentration and CK activity showed significant changes among phases (p = 0.049 and p = 0.014, respectively). Each physical activity examined showed a significant seasonal decrease (all p values were 0.001). Calprotectin serum concentration and indicators of muscular injury, inflammation, and physical activity were found to be correlated during particular stages of the seasonal examination.

CONCLUSIONS

Calprotectin values determined throughout one competitive season decreased as training intensity among water polo players increased. Serum calprotectin concentrations and indicators were related to biochemical markers of inflammation and muscle damage.

A Serological Neoepitope Biomarker of Neutrophil Elastase-Degraded Calprotectin, Associated with Neutrophil Activity, Identifies Idiopathic Pulmonary Fibrosis and Chronic Obstructive Pulmonary Disease More Effectively Than Total Calprotectin

Neutrophil activation can release neutrophil extracellular traps (NETs) in acute inflammation. NETs result in the release of human neutrophil elastase (HNE) and calprotectin, where the former can degrade the latter and generate protein fragments associated with neutrophil activity. We investigated this in chronic obstructive pulmonary disease (COPD) and idiopathic pulmonary fibrosis (IPF) using the novel neoepitope biomarker CPa9-HNE, quantifying a specific HNE-mediated fragment of calprotectin in serum. CPa9-HNE was compared to total calprotectin. Initially, CPa9-HNE was measured in healthy (n = 39), COPD (n = 67), and IPF (n = 16) serum using a neoepitope-specific competitive enzyme-linked immunosorbent assay. Then, a head-to-head comparison of CPa9-HNE and total calprotectin, a non-neoepitope, was conducted in healthy (n = 19), COPD (n = 25), and IPF (n = 19) participants. CPa9-HNE levels were significantly increased in COPD (p < 0.0001) and IPF subjects (p = 0.0001) when compared to healthy participants. Additionally, CPa9-HNE distinguished IPF (p < 0.0001) and COPD (p < 0.0001) from healthy participants more effectively than total calprotectin for IPF (p = 0.0051) and COPD (p = 0.0069). Here, CPa9-HNE also distinguished IPF from COPD (p = 0.045) participants, which was not observed for total calprotectin (p = 0.98). Neutrophil activity was significantly higher, as assessed via serum CPa9-HNE, for COPD and IPF compared to healthy participants. Additionally, CPa9-HNE exceeded the ability of non-neoepitope calprotectin serum measurements to separate healthy from lung disease and even COPD from IPF participants, indicating that neutrophil activity is essential for both COPD and IPF.

Calprotectin Is Associated with HETE and HODE Acids in Inflammatory Bowel Diseases

BACKGROUND

Intestinal diseases are identified as autoimmune phenomena attributed to a specific virus that binds to the mucosal epithelium. The importance of precise diagnostic processes and identification is emphasized, but the multifaceted and complex etiological factors pose challenges for effective treatment. A recent supplementary study suggested a linkage between the secretion of calprotectin, a protein associated with inflammatory processes, and increased levels of hydroxyeicosatrienoic acids (HETE) and hydroxyoctadecadienoic (HODE) compounds.

METHODS

Sixty-two patients (average age: 14.06 ± 2.93 years) suffering from inflammatory bowel diseases were included in this study. Comparative analyses were performed to assess the concentrations of calprotectin against the levels of arachidonic acid derivatives. The calprotectin concentration was determined using the enzyme-linked immunosorbent assay (ELISA) method. The derivatives of HETE and HODE were identified through liquid chromatography.

RESULTS

Patients with Crohn's disease (CD) displayed higher average concentrations of fatty acid metabolites; however, no correlation with calprotectin was observed. A dependency of 12S HETE concentration relative to age was noted in the CD group, and a similar trend was also identified in ulcerative colitis (UC), with the significant metabolites being 15 HETE and 5 oxoETE. In UC patients, a positive correlation was established between the calprotectin concentration and the acids 5-HETE and 12-HETE.

CONCLUSIONS

These findings may be instrumental for monitoring the inflammatory states of patients and indicating a pathway for intervention. The metabolite 16RS HETE is associated with UC activity, and 15-HETE is related to the disease's duration. A relatively more significant role of HETE acids in the progression of the disease was observed in UC.

Serum calprotectin correlates more strongly with inflammation and disease activity in ACPA positive than ACPA negative rheumatoid arthritis

OBJECTIVES

The aim of the present study was to evaluate performance of serum and synovial fluid levels of the granulocyte protein calprotectin as inflammatory biomarker in rheumatoid arthritis (RA) patients with knee synovitis.

METHODS

76 RA patients with ongoing knee synovitis were included. Data on disease activity score with 28 joints and their subcomponents and radiological destruction of the affected knee were collected. White blood cell count, C-reactive protein, anti-citrullinated peptide antibodies (ACPA) against cyclic citrullinated peptide version 2 (anti-CCP2), IgM rheumatoid factor (RF) and calprotectin were analysed in parallel in circulation and in synovial fluid (SF). Counts of polynuclear and mononuclear cells were measured in SF.

RESULTS

Serum (S) calprotectin correlated stronger than SF-calprotectin with inflammatory markers and disease activity. Instead, SF-calprotectin showed a strong correlation to SF counts of white blood cells, and especially to polymorphonuclear cell counts (Spearman's rho = 0.72, p< 0.001). S-calprotectin showed markedly stronger correlation with inflammatory markers and disease activity in ACPA positive as compared with ACPA negative RA patients; a similar difference was observed for patients with and without IgM RF.

CONCLUSION

The particularly strong association between circulating calprotectin and inflammation in ACPA positive RA is a new argument for a specific role for polymorphonuclear granulocytes/neutrophils in this RA subset. Measurement of calprotectin in SF does not convey any additional benefit compared with measurement in the circulation in RA patients with knee synovitis.

Evaluation of DiaSorin Liaison® calprotectin fecal assay adapted for pleural effusion

Objectives

Calprotectin (CP) is a calcium and zinc binding protein that is widely measured on faecal samples but its determination in other biological fluids might be of interest. The aim of this work was to validate the measurement of CP in pleural fluid by chemiluminescence.

Methods

LIAISON®XL, a fully automated chemiluminescence analyzer, was used for CP quantification on pleural fluid. A validation protocol was designed using both quality control materials provided by the manufacturer and pools of pleural fluid samples. Stability, imprecision, bias, linearity, detection capability and carry over effect were evaluated.

Results

CP was stable on pleural fluid at least one week, under refrigerated conditions, and four weeks at -80 °C. The observed intra- and inter-day imprecision was between 2.2 and 6.49 %, with a negative bias under 5.51 %. The linearity of the method was verified up to 2,000 ng/mL. The LoQ for the assay was 48.52 ng/mL. A statistically significant carry-over effect was observed after measuring CP concentrations above the upper limit of linearity, but given the observed magnitude, a clinically relevant impact should not be expected.

Conclusions

DiaSorin Liaison® calprotectin assay allows reliable measurement of CP in pleural fluid.

Clinical, Serological, and Immunological Characteristics of Greek Patients with Polymyalgia Rheumatica and/or Giant Cell Arteritis: A Research Protocol

Polymyalgia Rheumatica (PMR) and Giant Cell Arteritis (GCA) are chronic inflammatory disorders that usually affect older people. Although the aetiology of these diseases remains unknown, genetic, environmental, and immune factors have been implicated. Specific cytokines such as the IL-6, IL-1β, IL-12, IL-17, and interferon -γ seem to play an essential role. The diagnosis of the disease is usually based on clinical manifestations and the use of histology or imaging, while disease monitoring is based on physical examination, laboratory, and imaging findings. However, there is the unmet need in identifying possible biomarkers that could help the diagnosis and the monitoring as well. The present study aims to investigate the epidemiological, clinical, and immunological characteristics of PMR and/or GCA patients in the region of northwest Greece and to evaluate the role of specific molecules associated with the pathogenesis of the diseases, giving evidence to possible future biomarkers.

Assessing the Probiotic Effects of Pediococcus pentosaceus CACC616 in Weaned Piglets

During weaning, piglets experience various stressor events that disrupt their gut microbiota and immune balance, decrease growth parameters, and increase mortality rates. In this study, we assessed the efficacy of Pediococcus pentosaceus CACC616 as a probiotic supplement. We characterized this strain and evaluated its effect on improving growth performance, modulating gut microbiota composition, and reducing noxious odor components in weaned piglets compared to a non-supplementary diet (control). During the 26-day period, 40 crossbred weaned piglets were randomly assigned to pens with 20 animals each in two groups: control and treatment groups with CACC616. On day 26, the treatment group exhibited a lower feed conversion ratio (FCR) and a significant alteration in gut microbial composition, correlating with improved growth parameters and gut health (p < 0.05). The treatment group also exhibited significantly reduced digestibility- and intestinal-environment-related noxious odor components (p < 0.05). The CACC616 strain effectively reduced pathogenic genera numbers, including Campylobacter, Mogibacterium, Escherichia-Shigella, and Desulfovibrio spp., with the treatment group exhibiting lower fecal calprotectin levels than the control group (p < 0.05). Overall, this study revealed that the functional probiotic CACC616 contributes to enhanced FCR and effectively modulates weaned piglets' inflammation and intestinal microbiota.

Dynamics and Crosstalk between Gut Microbiota, Metabolome, and Fecal Calprotectin in Very Preterm Infants: Insights into Feeding Intolerance

BACKGROUND

Feeding intolerance (FI) is a significant concern in the care of preterm infants, impacting their growth and development. We previously reported that FI is linked to lower fecal calprotectin (FC) levels. This study aims to explore the postnatal dynamics and interplay between microbiota, metabolic profiles, and host immunity in preterm infants with and without FI.

METHODS

Infants with gestational age <32 weeks or birth weight <1500 g were enrolled at the Children's Hospital of Fudan University between January 2018 and October 2020. Weekly fecal samples were analyzed for bacterial profiling, metabolome, and calprotectin levels, exploring their longitudinal development and interrelationships.

RESULTS

Of the 118 very preterm infants studied, 48 showed FI. These infants experienced an interrupted microbial-immune trajectory, particularly at 3-4 weeks of age, marked by a reduced bacterial abundance, alpha diversity, and FC levels. Metabolic changes in FI were pronounced between 3 and 6 weeks. Pantothenic acid and two polyamine metabolites were closely associated with bacterial abundance and FC levels and negatively correlated with the duration to attain full enteral feeding.

CONCLUSIONS

FI infants demonstrated compromised microbiome-immune interactions, potentially influenced by specific metabolites. This research underscored the importance of early microbial and metabolic development in the pathogenesis of FI in very preterm infants.

Effectiveness of Oral Tofacitinib in Chronic Pouchitis: A Prospective, Open-Label Pilot Study

Oral tofacitinib can be effective in inducing response and remission in patients with chronic antibiotic refractory pouchitis. In addition to improving symptoms and quality of life, it can lead to improvement in endoscopic inflammation score and fecal calprotectin.

Fecal calprotectin measurement to detect recurrence of solitary juvenile polyps: A case report

RATIONALE

Juvenile polyps (JPs) are the most common polyp type and can be observed in 1% of all preschoolers. The peak incidence is observed at ages 3 to 5 years, constituting 90% of all polyps in children. Elevated levels of fecal calprotectin (FC) are often seen in children with JPs.

PATIENT CONCERNS

A 15-month-old girl was referred to our hospital for blood on the stool surface persisting for 3 months. She was healthy, with no abdominal pain, diarrhea, anorexia, or weight loss and no complaints other than hematochezia. Her physical examination, vital signs and laboratory date were unremarkable.

DIAGNOSIS

JPs.

INTERVENTION

Total colonoscopy for her found 2 JPs in the sigmoid colon, which were subsequently resected endoscopically.

OUTCOMES

At the age of 5 years, this patient again had bloody stools. Her FC measurement at that time was 1020 mg/kg, which normalized to 42 mg/kg 3 months after her second resection.

LESSONS

Single or multiple solitary JPs require follow-up that fully considers the possibility of recurrence. Establishing a method for early confirmation of JP recurrence based on bloody stools, fecal occult blood testing, and FC measurement is necessary.

Role of Fecal Calprotectin in Patients Presenting to the Emergency Department with Abdominal Pain with or without Diarrhea or Rectal Bleeding

BACKGROUND AND OBJECTIVE

Abdominal pain is a frequent reason for admission to the Emergency Department. It may be a symptom of an underlying "organic" disease or a "functional" manifestation without an underlying anatomic or physiologic alteration. The evaluation of patients with abdominal pain is a challenge for the emergency physician and the selection of patients for second-level radiological examinations or endoscopic procedures is not always easy to perform. Faecal calprotectin could be a useful diagnostic marker to distinguish between "organic" or "functional" form and its determination could be helpful to select patients for further examinations in the context of an emergency setting.

MATERIALS AND METHODS

This is an observational and retrospective study on 146 patients with abdominal pain and/or diarrhea (with or without rectal bleeding) admitted to the Emergency Department of Fondazione Policlinico Universitario A. Gemelli IRCCS, Rome, who collected a fecal sample to evaluate fecal calprotectin. We evaluated and correlated the level of fecal calprotectin with the final diagnosis they received.

RESULTS

50/146 patients (34,24%) received a diagnosis of acute diverticulitis, in particular, 14/50 (28%) were complicated and 36/50 (72%) were uncomplicated; 4/146 (2,7%) were cholangitis, 32/146 (21,9%) were colitis, 6/146 (4,1%) gastritis, 42/146 (28,7%), Irritable bowel syndrome and 12/146 (8,2%) Inflammatory bowel disease. For the differential diagnosis between Irriable or inflammatory bowel diseses, our study showed a VPP and a VPN of 100% meanwhile for the differential diagnosis between Acute complicated and uncomplicated diverticulitis, our study showed a VPP of 40% and a VPN of 84%.

CONCLUSION

In the emergency setting, faecal calprotectin could be a helpful marker to select patients with abdominal pain who need second-level radiological examinations or endoscopic procedures, guiding the emergency physician in the evaluation of such a complex and wideranging symptom.

Elevated Fecal Calprotectin Accompanied by Intestinal Neutrophil Infiltration and Goblet Cell Hyperplasia in a Murine Model of Multiple Sclerosis

Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system caused by myelin-specific autoreactive T cells. We previously demonstrated intestinal barrier disruption and signs of inflammation in experimental autoimmune encephalomyelitis (EAE), a model of MS. Fecal calprotectin is a disease activity biomarker in inflammatory bowel diseases, released by neutrophils in response to inflammation. We aimed to further investigate EAE manifestations in the gastrointestinal tract and to determine whether calprotectin is a useful biomarker of intestinal inflammation in EAE. Calprotectin was analyzed in feces, cecal contents, and plasma of EAE mice. Infiltrating neutrophils and goblet cells were investigated in different parts of the gastrointestinal tract before the onset of neurological symptoms and during established disease. We found increased calprotectin levels in feces, cecal content, and plasma preceding EAE onset that further escalated during disease progression. Increased neutrophil infiltration in the intestinal tissue concomitant with IL-17 expression and myeloperoxidase activity was found to correlate well with clinical activity. Increased goblet cells in the intestine, similar to irritable bowel syndrome (IBS), were also observed. The results suggest calprotectin as a good biomarker of gastrointestinal inflammation in EAE and the potential of this model as a useful animal model for IBS.

Expanded population of low-density neutrophils in juvenile idiopathic arthritis

Introduction

Juvenile idiopathic arthritis (JIA), a clinically variable disease characterized by autoimmune arthritis, affects children, and its immunopathology remains elusive. Alterations in neutrophil biology play an important role in this disease. In the present study, we aimed to explore the features of low-density neutrophils (LDNs) in patients with JIA.

Methods

Gene expression of peripheral blood mononuclear cells (PBMCs) from children with distinct subtypes of JIA was analyzed by NanoString Immunology panel. Presence of LDNs was ascertained by flow cytometry and the release of neutrophil-associated products were analyzed by LUMINEX.

Results

LDNs were detected in patients' peripheral blood mononuclear cells (PBMCs) after density gradient centrifugation. Transcriptomic analysis of JIA PBMCs revealed that genes related to neutrophil degranulation were markedly upregulated. The number of LDNs and level of their degranulation products increased in patients' PBMCs and correlated with serum calprotectin, but not with disease activity, sedimentation rate and C-reactive protein (CRP) levels. The phenotypes of LDNs varied from those of normal-density neutrophils and healthy donor LDNs. Phenotypical analysis revealed LDNs are immature and primed population with decreased suppressive capacity. A negative correlation between surface proteins CD62L, CD66b, and CD11b and the number of inflamed joints/JADAS was established.

Conclusion

Our results describe LDNs as primed, degranulated, immature cells with impaired suppressive activities. This work thus contributes to the increasing body of evidence that LDNs in JIA are altered and their role in the disease immunopathogenesis and possible clinical associations should be investigated further.

Elevated Level of Circulating but Not Urine S100A8/A9 Identifies Poor COVID-19 Outcomes

The alarmin calprotectin (S100A8/A9) is thought to drive a cytokine storm, a hallmark of severe COVID-19. Recent studies report circulating S100A8/A9 levels can distinguish COVID-19 severity but have only been conducted in non-U.S. cohorts and mainly focus on serum S100A8/A9 levels. Thus, we quantified S100A8/A9 in serum and urine samples from a hospital cohort in St. Louis, Missouri, to expand the understanding of S100A8/A9 as a prognostic biomarker for COVID-19. Elevated S100A8/A9 serum levels were observed in ICU patients (n = 49, p = 0.0370) and patients with fatal cases of COVID-19 (n = 76, p = 0.0018). We observed no correlation in the S100A8/A9 levels in matched serum and urine samples. Our results support the association of serum S100A8/A9 levels with COVID-19 severity and suggest that further investigation of urine S100A8/A9 as a COVID-19 biomarker is not warranted.

The Earlier You Find, the Better You Treat: Red Flags for Early Diagnosis of Inflammatory Bowel Disease

Delayed diagnosis is a challenge in the management of inflammatory bowel disease (IBD). Several studies show a significant association between diagnostic delay and disease progression to complications and surgery, especially in Crohn's disease (CD). What risk factors are associated with diagnostic delay in IBD remains unclear. In order to reduce diagnostic delay, the Red Flags Index has been developed and validated. The combination of the Red Flags Index score and non-invasive biomarkers such as fecal calprotectin seems to be highly accurate in screening patients with underlying IBD to be referred for further diagnostic workup and eventual early effective treatment strategies. Our literature review aims to obtain a comprehensive overview of the impacts of diagnostic delay in IBD on the potential risk factors associated with IBD, how diagnostic tools may be effective in reducing diagnostic delay, and future perspectives in this field.

Impact of Baseline Disease Activity and Trial Duration on Efficacy of Biologics in Active Crohn's Disease: Meta-analysis

BACKGROUND

Timings of assessment of efficacy and criteria used to define Crohn's disease (CD) activity at baseline may affect therapeutic gain of active drug over placebo in induction of remission trials in CD, but these issues have not been assessed systematically. We examined these issues in a meta-analysis.

METHODS

We searched the literature to June 2022 for randomized controlled trials of biologics vs placebo in active CD. We extracted clinical remission and response rates according to criteria used to define CD activity and time point of assessment, pooling them in a meta-analysis for all patients according to previous biologic exposure. We calculated the number needed to treat (NNT), with a 95% confidence interval (CI) to assess therapeutic gain of active drug over placebo according to these characteristics of trial design.

RESULTS

We identified 20 induction of remission trials (6754 patients). Rates of clinical remission were highest (42.6% with active drug vs 21.0% with placebo) and NNT lowest (5; 95% CI, 3-7.5) in trials using clinical and endoscopic activity to define active CD. Rates of remission were lower (26.5% with active drug, vs 18.6% with placebo) and NNT highest (12; 95% CI, 6-61) in trials using clinical activity alone. Results were similar according to previous biologic exposure. Time point of assessment seemed to have less of an effect, although the NNT was lowest in trials assessing remission rates at 9 to 12 weeks (NNT = 5.5; 95% CI, 4-8). Again, results were similar according to previous biologic exposure.

CONCLUSIONS

Both the criteria used to define CD activity at study entry and the time point used to confirm efficacy may be important in maximizing therapeutic gain of active drug over placebo.

Progression of Diabetic Kidney Disease and Gastrointestinal Symptoms in Patients with Type I Diabetes

(1) Background: Little research is conducted on the link between diabetic kidney disease (DKD) progression and diabetic gastroenteropathy in type 1 diabetes (T1D). (2) Methods. We performed a cross-sectional study with 100 T1D patients; 27 of them had progressive DKD, defined as an estimated glomerular filtration rate (eGFR) decline ≥3 mL/min/year or increased albuminuria stage, over a mean follow-up time of 5.89 ± 1.73 years. A newly developed score with 17 questions on gastrointestinal (GI) symptoms was used. Faecal calprotectin was measured by ELISA. Lower GI endoscopies were performed in 21 patients. (3) Results: The gastrointestinal symptom score demonstrated high reliability (Cronbach's α = 0.78). Patients with progressive DKD had higher GI symptom scores compared to those with stable DKD (p = 0.019). The former group demonstrated more frequent bowel movement disorders (p < 0.01). The scores correlated negatively with eGFR (r = -0.335; p = 0.001), positively with albuminuria (r = 0.245; p = 0.015), Hba1c (r = 0.305; p = 0.002), and diabetes duration (r = 0.251; p = 0.012). Faecal calprotectin levels did not differ between DKD groups significantly. The most commonly reported histopathological findings of enteric mucosa were infiltration with eosinophils, lymphocytes, plasmacytes, the presence of lymphoid follicles, and lymphoid aggregates. Conclusion: The progression of DKD is positively correlated with gastrointestinal symptoms; however, more research is needed to clarify the causal relationships of the gut-kidney axis in T1D.

Pro-Inflammatory Diet Is Correlated with High Veillonella rogosae, Gut Inflammation and Clinical Relapse of Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) are chronic conditions arising from an intricate interplay of genetics and environmental factors, and are associated with gut dysbiosis, inflammation, and gut permeability. In this study, we investigated whether the inflammatory potential of the diet is associated with the gut microbiota profile, inflammation, and permeability in forty patients with IBD in clinical remission. The dietary inflammatory index (DII) score was used to assess the inflammatory potential of the diet. The fecal microbiota profile was analyzed using 16SrRNA (V3-V4) gene sequencing, while fecal zonulin and calprotectin levels were measured with enzyme-linked immunosorbent assays. We found a positive correlation between the DII score and elevated calprotectin levels (Rho = 0.498; p = 0.001), but not with zonulin levels. Although α- and β-diversity did not significantly differ across DII quartiles, the most pro-inflammatory diet group exhibited a higher fecal abundance of Veillonella rogosae (p = 0.026). In addition, the abundance of some specific bacteria sequences showed an exponential behavior across DII quartiles and a correlation with calprotectin or zonulin levels (p ≤ 0.050). This included a positive correlation between sq702. Veillonella rogosae and fecal calprotectin levels (Rho = 0.419, p = 0.007). DII, calprotectin, and zonulin levels were identified as significant predictors of 6-month disease relapse (p ≤ 0.050). Our findings suggest a potential relationship of a pro-inflammatory diet intake with Veillonella rogosae and calprotectin levels in IBD patients in clinical remission, which may contribute to disease relapse.

Microbiome profile and calprotectin levels as markers of risk of recurrent Clostridioides difficile infection

Introduction

Clostridioides difficile infection (CDI) is the main cause of nosocomial diarrhoea in developed countries. Recurrent CDI (R-CDI), which affects 20%-30% of patients and significantly increases hospital stay and associated costs, is a key challenge. The main objective of this study was to explore the role of the microbiome and calprotectin levels as predictive biomarkers of R-CDI.

Methods

We prospectively (2019-2021) included patients with a primary episode of CDI. Clinical data and faecal samples were collected. The microbiome was analysed by sequencing the hypervariable V4 region of the 16S rRNA gene on an Illumina Miseq platform.

Results

We enrolled 200 patients with primary CDI, of whom 54 developed R-CDI and 146 did not. We analysed 200 primary samples and found that Fusobacterium increased in abundance, while Collinsella, Senegalimassilia, Prevotella and Ruminococcus decreased in patients with recurrent versus non-recurrent disease. Elevated calprotectin levels correlated significantly with R-CDI (p=0.01). We built a risk index for R-CDI, including as prognostic factors age, sex, immunosuppression, toxin B amplification cycle, creatinine levels and faecal calprotectin levels (overall accuracy of 79%).

Discussion

Calprotectin levels and abundance of microbial genera such as Fusobacterium and Prevotella in primary episodes could be useful as early markers of R-CDI. We propose a readily available model for prediction of R-CDI that can be applied at the initial CDI episode. The use of this tool could help to better tailor treatments according to the risk of R-CDI.

Fecal Calprotectin for the Diagnosis and Management of Inflammatory Bowel Diseases

Calprotectin is a heterodimeric calcium- and zinc-binding protein mainly derived from the cytoplasm of neutrophils that has direct antimicrobial functions and a role in the regulation of the innate immune response. It can be found in various biological compartments, in particular, the stool, with concentrations related to the level of mucosal inflammation. The measurement of fecal calprotectin has thus been recognized as a useful surrogate marker to distinguish patients with inflammatory bowel disease from those with irritable bowel syndrome. Moreover, it allows the monitoring of intestinal inflammation with a high negative predictive value, making it possible to exclude the diagnosis of inflammatory bowel disease for symptomatic patients. It also shows high sensitivity for the identification of patients requiring additional examinations for diagnosis, such as colonoscopy, and the evaluation of therapeutic responses, providing evidence of relapse or mucosal healing, which can lead to the intensification or reduction of treatment. As calprotectin levels are a measure of mucosal inflammation, high fecal concentrations are also found in other diseases with an inflammatory component, such as infectious enteritis or colorectal cancer. Interpretation of the concentration must therefore always take into account the clinical history and symptoms specific to each patient.

S100A8 and S100A9 in Hematologic Malignancies: From Development to Therapy

S100A8 and S100A9 are multifunctional proteins that can initiate various signaling pathways and modulate cell function both inside and outside immune cells, depending on their receptors, mediators, and molecular environment. They have been reported as dysregulated genes and proteins in a wide range of cancers, including hematologic malignancies, from diagnosis to response to therapy. The role of S100A8 and S100A9 in hematologic malignancies is highlighted due to their ability to work together or as antagonists to modify cell phenotype, including viability, differentiation, chemosensitivity, trafficking, and transcription strategies, which can lead to an oncogenic phase or reduced symptoms. In this review article, we discuss the critical roles of S100A8, S100A9, and calprotectin (heterodimer or heterotetramer forms of S100A8 and S100A9) in forming and promoting the malignant bone marrow microenvironment. We also focus on their potential roles as biomarkers and therapeutic targets in various stages of hematologic malignancies from diagnosis to treatment.

S100A8/A9-alarmin promotes local myeloid-derived suppressor cell activation restricting severe autoimmune arthritis

Immune-suppressive effects of myeloid-derived suppressor cells (MDSCs) are well characterized during anti-tumor immunity. The complex mechanisms promoting MDSC development and their regulatory effects during autoimmune diseases are less understood. We demonstrate that the endogenous alarmin S100A8/A9 reprograms myeloid cells to a T cell suppressing phenotype during autoimmune arthritis. Treatment of myeloid precursors with S100-alarmins during differentiation induces MDSCs in a Toll-like receptor 4-dependent manner. Consequently, knockout of S100A8/A9 aggravates disease activity in collagen-induced arthritis due to a deficit of MDSCs in local lymph nodes, which could be corrected by adoptive transfer of S100-induced MDSCs. Blockade of MDSC function in vivo aggravates disease severity in arthritis. Therapeutic application of S100A8 induces MDSCs in vivo and suppresses the inflammatory phenotype of S100A9ko mice. Accordingly, the interplay of T cell-mediated autoimmunity with a defective innate immune regulation is crucial for autoimmune arthritis, which should be considered for future innovative therapeutic options.

Analysis of Calprotectin as an Early Marker of Infections Is Economically Advantageous in Intensive Care-Treated Patients

Calprotectin is released from neutrophil granulocytes upon activation. Several studies have indicated that plasma calprotectin is an early determinant of bacterial infections, which may serve as a diagnostic tool facilitating decision making on antibiotic treatment. The study objective was to explore the health and economic implications of calprotectin as a predictive tool to initiate antimicrobial therapy in a cohort of critically ill patients. Thus, data obtained from a previously published study on calprotectin as a hypothetical early biomarker of bacterial infections in critically ill patients were evaluated regarding the potential cost-effective impact of early analysis of calprotectin on an earlier start of antibiotic treatment. Under the assumption that calprotectin is used predictively and comparators (white blood cells, procalcitonin, and C-reactive protein) are used diagnostically, a cost-effective impact of EUR 11,000-12,000 per patient would be obtained. If calprotectin would be used predictively and comparators would be used predictively for 50% of patients, it is hypothesized that cost-effectiveness would be between EUR 6000 and 7000 per patient, based on reduced stay in the ICU and general ward, respectively. Furthermore, predictive use of calprotectin seems to reduce both mortality and the length of hospital stay. This health economic analysis on the predictive use of plasma calprotectin, which facilitates clinical decision making in cases of suspected sepsis, indicates that such determination has a cost-saving and life-saving impact on the healthcare system.

Immune complex-mediated neutrophil activation in patients with polymyalgia rheumatica

OBJECTIVE

Neutrophils are important in host defence. However, neutrophils are also linked to inflammation and organ damage. The purpose of this study was to assess whether markers of neutrophil activation are increased in PMR.

METHODS

Levels of immune complexes (IC), calprotectin and neutrophil extracellular traps (NETs) were measured in plasma of healthy individuals (n = 30) and patients with PMR (n = 60), at flare and upon treatment with glucocorticoids using ELISA. Plasma-mediated neutrophil activation was assessed in presence of an FcγRIIA inhibitory antibody (IV.3).

RESULTS

Plasma levels of calprotectin and NETs were elevated in PMR (P < 0.001). Mechanistically, neutrophil activation was driven by ICs, present in plasma, able to up-regulate neutrophil activation markers CD66b and CD11b (P < 0.0001) in an FcγRIIA-dependent manner (P < 0.01). Of note, circulating levels of IC correlated with plasma induced CD66b and CD11b (r = 0.51, P = 0.004, and r = 0.46, P = 0.01, respectively) and decreased after glucocorticoid therapy. In contrast to NETs, calprotectin significantly decreased after glucocorticoid therapy (P < 0.001) and was higher in PMR without overlapping GCA compared with patients with overlapping disease (P = 0.014). Interestingly, musculoskeletal involvement was associated with elevated levels of calprotectin before initiation of glucocorticoid therapy (P = 0.036).

CONCLUSIONS

Neutrophil activation, including NET formation, is increased in PMR, through IC-mediated engagement of FcγRIIA. Clinically, neutrophil activation is associated with musculoskeletal involvement, with calprotectin, but not NETs, being a biomarker of treatment response in PMR patients. In all, IC-mediated neutrophil activation is a central process in PMR pathogenesis identifying potential novel therapeutic targets (FcγRIIA), as well as soluble markers for disease monitoring (calprotectin).

Is a Lower Dose of More Bioavailable Iron (18-mg Ferrous Bisglycinate) Noninferior to 60-mg Ferrous Sulfate in Increasing Ferritin Concentrations While Reducing Gut Inflammation and Enteropathogen Detection in Cambodian Women? A Randomized Controlled Noninferiority Trial

BACKGROUND

Global guidelines recommend untargeted iron supplementation for women in regions of anemia prevalence ≥40%, such as Cambodia. However, the potential harms of untargeted iron on the gut have not been rigorously studied in women and likely vary depending on iron dose and form.

OBJECTIVES

We investigated if a lower dose of a highly bioavailable iron amino acid chelate was as effective as the standard dose of iron salts in increasing ferritin concentrations and whether any differences were observed in gut inflammation or enteropathogen detection.

METHODS

A double-blind, randomized placebo-controlled noninferiority trial was conducted in Cambodia. Nonpregnant women (n = 480, 18-45 y) were randomly assigned to 60-mg ferrous sulfate, 18-mg ferrous bisglycinate, or placebo for 12 wk. Nonfasting blood and stool specimens were collected at baseline and 12 wk. Ferritin and fecal calprotectin were measured with an ELISA. A molecular assay was used to detect 11 enteropathogens in a random subset of n = 100 women. Generalized linear mixed-effects models were used to estimate the adjusted mean difference in ferritin concentrations at 12 wk (primary outcome), as compared with our 'a priori' noninferiority margin of 20 μg/L.

RESULTS

Baseline anemia and iron deficiency prevalence was low (17% and 6%, respectively). The adjusted mean difference in ferritin concentrations between the iron groups was 14.6 (95% confidence interval [CI]: 7.6, 21.6) μg/L. Mean ferritin concentration at 12 wk was higher in the ferrous sulfate (99 [95% CI: 95, 103] μg/L, P < 0.001) than in ferrous bisglycinate (84 [95% CI: 80, 88] μg/L) and placebo groups (78 [95% CI: 74, 82] μg/L). No differences in fecal calprotectin concentrations or enteropathogen detection were observed across groups at 12 wk.

CONCLUSIONS

Ferrous bisglycinate (18-mg) was not as effective as ferrous sulfate (60-mg) in increasing ferritin concentrations and did not differentially influence biomarkers of gut health in this predominantly iron-replete population of Cambodian women. This trial was registered at clinicaltrials.gov registry as NCT04017598.

Identifying predictors of clinical outcomes using the projection-predictive feature selection-a proof of concept on the example of Crohn's disease

Objectives

Several clinical disease activity indices (DAIs) have been developed to noninvasively assess mucosal healing in pediatric Crohn's disease (CD). However, their clinical application can be complex. Therefore, we present a new way to identify the most informative biomarkers for mucosal inflammation from current markers in use and, based on this, how to obtain an easy-to-use DAI for clinical practice. A further aim of our proof-of-concept study is to demonstrate how the performance of such a new DAI can be compared to that of existing DAIs.

Methods

The data of two independent study cohorts, with 167 visits from 109 children and adolescents with CD, were evaluated retrospectively. A variable selection based on a Bayesian ordinal regression model was applied to select clinical or standard laboratory parameters as predictors, using an endoscopic outcome. The predictive performance of the resulting model was compared to that of existing pediatric DAIs.

Results

With our proof-of-concept dataset, the resulting model included C-reactive protein (CRP) and fecal calprotectin (FC) as predictors. In general, our model performed better than the existing DAIs. To show how our Bayesian approach can be applied in practice, we developed a web application for predicting disease activity for a new CD patient or visit.

Conclusions

Our work serves as a proof-of-concept, showing that the statistical methods used here can identify biomarkers relevant for the prediction of a clinical outcome. In our case, a small number of biomarkers is sufficient, which, together with the web interface, facilitates the clinical application. However, the retrospective nature of our study, the rather small amount of data, and the lack of an external validation cohort do not allow us to consider our results as the establishment of a novel DAI for pediatric CD. This needs to be done with the help of a prospective study with more data and an external validation cohort in the future.

Calprotectin and periostin levels in periodontitis patients with coronary artery disease

OBJECTIVE

The aim of the study was to assess the effect of non-surgical periodontal therapy (NSPT) on periodontal and cardiac parameters as well as on the expression of calprotectin and periostin levels in periodontitis patients with and without coronary artery disease (CAD).

METHODS

Ninety subjects were categorised into three groups: Group H: periodontally and systemically healthy subjects, Group P: stage III grade B periodontitis subjects with no associated systemic diseases and Group P + CAD: stage III grade B periodontitis subjects diagnosed with CAD. Demographic, periodontal and cardiac parameters were recorded at baseline (0 day) and on the 180th day after NSPT. Gingival crevicular fluid was collected from all participants at baseline (0 day) and after the 180th day. Calprotectin and periostin expression were reassessed.

RESULTS

A significant increase in the levels of calprotectin (34.05 ± 11.72) was seen at baseline in the P + CAD group, whereas on the contrary, a decreased periostin (1.59 ± 0.41) was also noted at baseline. The study also showed a significant improvement in periodontal and cardiac parameters on the 180th day following NSPT.

CONCLUSION

Detection of calprotectin and periostin expression in GCF samples could represent a link to the association of periodontitis and CAD.

Early fecal calprotectin levels at week 8 may guide therapeutic decisions on Ustekinumab therapy in patients with Crohn's disease

BACKGROUND

Response evaluation after induction therapy with ustekinumab (UST) in Crohn's disease (CD) is important for decisions on maintenance therapy. We aimed to assess the potential of fecal calprotectin (FC) levels to predict endoscopic response at week 16.

METHODS

CD patients with FC >100 µg/g and endoscopic active disease (SES-CD> 2, Rutgeerts' score ≥ i2) at initiation of UST therapy were enrolled. FC was determined at weeks 0, 2, 4, 8 and 16 and patients underwent a colonoscopy at week 16. The primary outcome was an endoscopic response at week 16 (SES-CD score ≥50% decrease or a decrease of ≥1 points in Rutgeerts' score). The optimal cut-off levels of FC and change in FC to predict endoscopic response were determined using ROC statistics.

RESULTS

59 CD patients were included. Endoscopic response was observed in 21/59 (36%) patients. The diagnostic accuracy for FC levels at week 8 to predict endoscopic response at week 16 showed a predictive value of 0.71. A decrease in FC levels ≥500 µg/g between baseline at week 8 indicates endoscopic response (PPV = 89%), whereas absence of any decrease indicates endoscopic non-response after induction (NPV = 81%).

CONCLUSIONS

Continuation of UST therapy without endoscopic response evaluation may be considered in patients with a decrease in FC levels of ≥500 µg/g at week 8. The decision on continuation of UST therapy or therapy optimization needs reconsideration in patients without a decrease of FC level. In all other patients, endoscopic response evaluation of induction therapy remains essential for therapeutic decisions.

Current and emerging biomarkers for ulcerative colitis

INTRODUCTION

Ulcerative colitis (UC) is a chronic illness requiring lifelong management that could be enhanced by personalizing care using biomarkers.

AREAS COVERED

The main biomarker discovery modalities are reviewed, highlighting recent results across the spectrum of applications, including diagnostics (serum anti-αvβ6 antibodies achieving an area under the curve [AUC] = 0.99; serum oncostatin M AUC = 0.94), disease activity assessment (fecal calprotectin and serum trefoil factor 3: AUC > 0.90), prognostication of the need for treatment escalation (whole blood transcriptomic panels and CLEC5A/CDH2 ratio: AUC > 0.90), prediction of treatment response, and early identification of patients with subclinical disease. The use of established biomarkers is discussed, along with new evidence regarding autoantibodies, proteins, proteomic panels, transcriptomic signatures, deoxyribonucleic acid methylation patterns, and UC-specific glycomic and metabolic disturbances.

EXPERT OPINION

Novel biomarkers will pave the way for optimized UC care. However, validation, simplification, and direct clinical translation of complex models may prove challenging. Currently, few candidates exist to assess key characteristics, such as UC susceptibility, histological disease activity, drug response, and long-term disease behavior. Further research will likely not only reveal new tools to tackle these issues but also contribute to understanding UC pathogenesis mechanisms.

Serum α1-Proteinase Inhibitor, Calprotectin, and S100A12 Concentrations in the Characterization of Pancreatitis in Dogs

Miniature Schnauzers are predisposed to develop pancreatitis, with familial hypertriglyceridemia (HTG) described as a potential risk factor. Diagnosing pancreatitis in dogs is based on the integration of serum canine-specific pancreatic lipase (cPLI) concentration, clinical presentation, and diagnostic imaging findings. However, markers of systemic inflammation and antiprotease activity have not been extensively investigated in the characterization and prognostication of pancreatitis in dogs. Serum concentrations of alpha₁-proteinase inhibitor (α₁PI; as a marker of systemic antiprotease response) and calprotectin and S100A12 (as markers of systemic inflammation) were measured in serum samples from 35 Miniature Schnauzers diagnosed with pancreatitis (serum cPLI concentration >400 μg/L, clinical signs, abdominal imaging findings). These markers were evaluated for possible associations with patient characteristics, clinical presentation, risk factors for pancreatitis, and outcome. The study showed that biomarkers of systemic inflammation and antiprotease activity are commonly increased in Miniature Schnauzers with pancreatitis. Whereas serum calprotectin and S100A12 concentrations were found to have limited utility in differentiating pancreatitis presentations, serum α₁PI concentrations and potentially also the serum calprotectin-to-S100A12 ratio might be non-invasive surrogate markers of disease severity in dogs with pancreatitis.

Synovial Calprotectin for Diagnosing Periprosthetic Joint Infection in Loose Hip and Knee Arthroplasties: A Prospective Cohort Study

BACKGROUND/AIM

Synovial calprotectin has been demonstrated as a promising biomarker for periprosthetic joint infections (PJI) in painful total hip (THA) and knee arthroplasties (TKA). However, its diagnostic utility has not been evaluated explicitly in cases with marked loosening or migration of the implant. Concerns have already been raised in cases with metallosis and severe periprosthetic osteolysis because wear-induced inflammation may yield false positive results. The purpose of this study was to evaluate calprotectin for the diagnosis of PJI in cases that preoperatively demonstrate moderate to severe periprosthetic osteolysis or implant migration as signs for implant loosening in THA and TKA.

PATIENTS AND METHODS

Thirty-three patients were included in this prospective study between February of 2019 and November of 2021. The extent of osteolysis was classified according to Engh et al., Paprosky et al., and the modern Knee Society Radiographic Evaluation and Scoring System. Synovial white blood cell count (WBC), percentage of polymorphonuclear neutrophils (PMC), serum C-reactive protein (CRP) and synovial calprotectin using a lateral-flow-assay were tested against the European Bone and Joint Infection Society (EBJIS) definition for PJI. Statistic quality criteria were calculated and compared using a binary classification test.

RESULTS

Ten patients were classified as confirmed infections according to the EBJIS definition (7 THA and 5 TKA). The calprotectin assay yielded a sensitivity of 0.60, a specificity of 0.61, a positive predictive value of 0.40, and a negative predictive value of 0.78. The calprotectin assay resulted in nine false positive and four false negative cases. No correlation between the extent of osteolysis and false classification by means of the calprotectin assay was observed.

CONCLUSION

The diagnostic accuracy of synovial calprotectin is impaired if moderate to severe signs of implant loosening are present. If PJI is unlikely, the calprotectin LFT can be applied as a further exclusion tool as the negative predictive value remains relatively high.