Calprotectin Concentrations Research Articles

Meconium Proteins Involved in Iron Metabolism.

The lack of specific biological materials and biomarkers limits our knowledge of the mechanisms underlying intrauterine regulation of iron supply to the fetus. Determining the meconium content of proteins commonly used in the laboratory to assess the transport, storage, and distribution of iron in the body may elucidate their roles in fetal development. Ferritin, transferrin, haptoglobin, ceruloplasmin, lactoferrin, myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL), and calprotectin were determined by ELISA in meconium samples obtained from 122 neonates. There were strong correlations between the meconium concentrations of haptoglobin, transferrin, and NGAL (p < 0.05). Meconium concentrations of ferritin were several-fold higher than the concentrations of the other proteins, with the exception of calprotectin whose concentration was approximately three-fold higher than that of ferritin. Meconium ceruloplasmin concentration significantly correlated with the concentrations of MPO, NGAL, lactoferrin, and calprotectin. Correlations between the meconium concentrations of haptoglobin, transferrin, and NGAL may reflect their collaborative involvement in the storage and transport of iron in the intrauterine environment in line with their recognized biological properties. High meconium concentrations of ferritin may provide information about the demand for iron and its utilization by the fetus. The associations between ceruloplasmin and neutrophil proteins may indicate the involvement of ceruloplasmin in the regulation of neutrophil activity in the intrauterine environment.

Salivary calprotectin and neutrophils in inflammatory bowel disease in relation to oral diseases

AbstractObjectiveCalprotectin is elevated in saliva from inflammatory bowel disease (IBD) patients, but it is also affected by oral disease. We assessed the salivary concentration of calprotectin in IBD patients, in relation to intestinal and oral diseases. Furthermore, we investigated the phenotype of salivary neutrophils from IBD patients, and their ability to secrete calprotectin.Materials and MethodsThirty IBD patients and 26 controls were orally examined and sampled for stimulated saliva. Twenty‐five IBD patients provided fresh fecal samples. Calprotectin concentrations in saliva and feces were determined by an enzyme‐linked immunosorbent assay. Expression of CD11b, CD15, and CD16 on oral neutrophils was assessed by flow cytometry. Secretion of calprotectin was evaluated in cultured oral neutrophils.ResultsCalprotectin was significantly elevated in saliva of IBD patients compared to controls, particularly in Crohn's disease, irrespective of caries or periodontitis. Salivary calprotectin did not correlate to fecal calprotectin. CD11b expression was significantly reduced in salivary neutrophils from IBD patients. Salivary neutrophils from IBD patients tended to secrete more calprotectin than controls.ConclusionsSalivary calprotectin is elevated in IBD regardless of oral diseases. Furthermore, salivary neutrophils secrete calprotectin, and display lower CD11b expression in IBD.

Urinary calprotectin as a diagnostic tool for detecting significant bacteriuria

Pyuria in dipstick examination serves as the most widespread screening tool for urinary tract infections (UTI). The absence of pyuria, however, does not exclude UTI. We investigated the diagnostic value of urinary calprotectin, a mediator protein of the innate immune system, which is released by leukocytes, for the detection of UTI and compared it with dipstick pyuria. Since even low numbers of leukocytes in the urine significantly increase urinary calprotectin concentrations, calprotectin might be a more sensitive marker than pyuria detected by dipstick. All 162 patients were prospectively included and underwent a urine dipstick, urine culture, quantification of proteinuria and determination of calprotectin in the urine. Urinary calprotectin was determined using an enzyme-linked immunosorbent assay (ELISA). UTI was defined as urine cultures with detection of one or a maximum of two uropathogenic bacteria with ≥ 105 colony-forming units per millilitre (CFU/ml). Exclusion criteria were acute kidney injury, chronic renal insufficiency and tumors of the urinary tract. 71 (43.8%) patients had a UTI. Of the 91 patients without UTI, 23 had a contamination and 19 had evidence of ≥ 105 CFU/ml considered to be asymptomatic bacteriuria. The median calprotectin concentration in patients with UTI and pyuria was significantly higher than in patients with UTI and without pyuria (5510.4 vs. 544.7 ng/ml). In ROC analyses, calprotectin revealed an area under the curve (AUC) of 0.70 for the detection of significant bacteriuria. Pyuria in dipstick examinations provided an AUC of 0.71. There was no significant difference between these AUCs in the DeLong test (p = 0.9). In patients with evidence of significant bacteriuria but without pyuria, a significantly higher calprotectin concentration was measured in the urine than in patients with neither pyuria nor UTI (544.7 ng/ml vs 95.6 ng/ml, p = 0.029). Urinary calprotectin is non-inferior to dipstick pyuria in the detection of UTI.

Is there a role of calprotectin testing in the diagnosis of surgical site infections after total hip and knee arthroplasty? A preliminary study.

Recent studies have revealed the usefulness of synovial calprotectin (CLP) in diagnosing chronic periprosthetic joint infections (PJIs). However, there is still a lack of evidence to support the use of serum CLP in the diagnosis of early PJIs and surgical site infections (SSIs) after total joint arthroplasties (TJAs). The primary aim of this study is to investigate the standard kinetics of CLP concentrations in the blood during the very early postoperative period after non-complicated total hip arthroplasty (THA) and total knee arthroplasty (TKA). The secondary aim was to perform a preliminary comparison of CLP concentrations between non-infected patients and patients with recognized SSIs. A total of 64 consecutive patients who underwent primary THA and TKA were included in this prospective research. Sixty patients (30 THA and 30 TKA) were scheduled to determine the standard shape of the blood CLP curve and the expected concentrations during the first 5 postoperative days after non-complicated TJAs. In 4 additonal patients, early SSI was confirmed, and they were included in a separate SSI subgroup. Calprotectin demonstrated a linear increase during the first 5 postoperative days. Statistically significant differences in CLP concentrations between non-infected cases and SSIs were not observed. The preoperative median results with interquartile range (Q1-Q3) were 0.52 (0.39-0.64) mg/dL and 0.5 (0.47-0.52) mg/dL (p = 0.77), while post operation they were as follows: on postoperative day 1: 0.88 (0.53-1.3) mg/dL and 0.86 (0.62-1.1) mg/dL (p = 0.84), on postoperative day 3: 1.77 (1.29-2.08) mg/dL and 1.85 (1.70-1.95) mg/dL (p = 0.72), and on postoperative day 5: 2.32 (1.79-2.67) mg/dL and 2.56 (2.25-2.83) mg/dL (p = 0.55), respectively. Serial CLP measurements during the early postoperative period revealed a linear (statistically significant) increase in concentration to postoperative day 5 without an evident point of decrease. A significant difference in median values and the course of curve patterns between the non-complicated and SSI groups was not observed.

241 Immunophysiology and performance of broilers supplemented with macroalgal sulfated polysaccharides during a subclinical necrotic enteritis challenge

Abstract This study evaluated the effects of a sulfate polysaccharide extracted from marine algae product on performance, intestinal lesion scores, and mRNA abundance of various tight junction proteins and immune response genes. A total of 600 one-day old male broilers (Ross 708) were allocated to one of four treatment groups (6 replicate floor pens, 25 birds/pen): negative control (NC) group fed a corn-soybean meal diet; positive control (PC) fed NC + 15 ppm Avilamycin and 125 ppm Amprolium, an additive group (AGS) fed NC + Algoguard added at 0.1% of the diet, and (AGH) fed NC + Algoguard added at 0.2% of the diet. To predispose the birds to NE, birds were orally gavaged with 2,000 Eimeria maxima sporulated oocysts on d 14 followed by a dose of approximately 1×108 CFU/mL of C. perfringens on d 19. On d 21, four birds/pen were necropsied for NE lesions and on d 14, 21, and 42 jejunal samples were collected to assess mRNA abundance. Birds and feed were weighed on d 14, 21, 28, and 42 on a per pen basis. Average daily gain (ADG), average daily feed intake (ADFI), and feed conversion ratio (FCR) were calculated during each feeding phase and adjusted for daily mortality. The data were analyzed using ANOVA (JMP, Pro 16) and significance (P ≤ 0.05) was determined by the LSD test. During d 14-21, 0-21, 0-28, and 0-42, mortality rate and ADFI were significantly less in AGS, AGH, and PC compared with NC. ADG was greater while FCR was significantly less in PC, AGS, and AGH during d 21-28, 0-28, and 0-42 compared with NC (P ≤ 0.05). Lesion severity was also significantly less in AGS, AGH, and PC compared with NC. On d 14, 21, and 42 there were no toxins present in the tested serum samples. Calprotectin concentration was greater in PC and NC on d 21 and 42 compared with the supplemented groups. C. perfringens toxin was not detected in serum samples of any of the four treatment groups. mRNA abundance of CLDN1, IL1β, IL12B, and IL10 was greater in AGS compared with NC on d 14 and 42. ZO1 was significantly greater on d 21 in PC treatment and was less than both AGS and AGH on d 42 (P ≤ 0.05). Compared with all other treatments, mRNA abundance of OCLDN was greater and those of IFN-γ and ZO2 were less in PC, while that of CLDN3 showing no significant difference among all 4 treatments. To conclude, dietary inclusion of this algal product in broiler diets could be considered as a beneficial alternative to antibiotic growth promoters in the context of this challenge model.

Noninvasive Markers of Inflammation and Protein Loss Augment Diagnosis of Pediatric Celiac Disease.

Circulating tissue transglutaminase immunoglobulin A concentration is a sensitive and specific indicator of celiac disease, but discrepancies between serologic and histologic findings occur. We hypothesized that fecal markers of inflammation and protein loss would be greater in patients with untreated celiac disease than in healthy controls. Our study aims to evaluate multiple fecal and plasma markers in celiac disease and correlate these findings with serologic and histologic findings as noninvasive means of evaluating disease activity. Participants with positive celiac serologies and controls with negative celiac serologies were prospectively enrolled before upper endoscopy. Blood, stool, and duodenal biopsies were collected. Concentrations of fecal lipocalin-2, calprotectin, and alpha-1-antitrypsin and plasma lipocalin-2 were determined. Biopsies underwent modified Marsh scoring. Significance was tested between cases and controls, modified Marsh score and tissue transglutaminase immunoglobulin A concentration. Lipocalin-2 was significantly elevated in the stool ( P = 0.006) but not the plasma of participants with positive celiac serologies. There was no significant difference in fecal calprotectin or alpha-1 antitrypsin between participants with positive celiac serologies and controls. Fecal alpha-1 antitrypsin >100 mg/dL was specific, but not sensitive for biopsy-proven celiac disease. Lipocalin-2 is elevated in the stool but not the plasma of patients with celiac disease suggesting a role of local inflammatory response. Calprotectin was not a useful marker in the diagnosis of celiac disease. While random fecal alpha-1 antitrypsin was not significantly elevated in cases compared with controls, an elevation of greater than 100 mg/dL was 90% specific for biopsy-proven celiac disease.

Diagnostic Value of Faecal Calprotectin in Children with Chronic Gastrointestinal Disorders at Yaounde General Hospital

&amp;lt;i&amp;gt;Introduction&amp;lt;/i&amp;gt;: Chronic gastrointestinal disorders are common in children. Numerous faecal biomarkers, such as faecal calprotectin, are used in the aetiological diagnosis of these digestive disorders. The study aimed to investigate the diagnostic value of faecal calprotectin in paediatric chronic gastrointestinal disease compared with that obtained in healthy children. &amp;lt;i&amp;gt;Methodology&amp;lt;/i&amp;gt;: This was a comparative, analytical cross-sectional study from October 2022 through June 2023 at Yaoundé General Hospital. Participants were children aged between four and eighteen with chronic digestive disorders. Using a pre-established questionnaire, we collected the socio-demographic and clinical characteristics of each participant. The participants&amp;apos; faecal calprotectin was tested at the laboratory of the Yaoundé University Hospital Center by Enzyme-Linked Immunosorbent Assay (ELISA). Associations between variables were investigated by linear regression and calculation of the odds ratio (OR). The significance threshold was 5%. &amp;lt;i&amp;gt;Results&amp;lt;/i&amp;gt;: Sixty stool samples were analysed for faecal calprotectin from 30 patients and 30 healthy participants. The mean age of the population was 9.47 (± 3.35) years for patients and 10.67 (± 3.70) years for healthy participants, with a sex ratio of 1.14 for patients and 0.87 for healthy participants. The threshold value for faecal calprotectin was 2.75 µg/g, with a sensitivity of 60%, a specificity of 63%, a positive predictive value of 61.20% and a negative predictive value of 62.06%. There were no significant differences in faecal calprotectin concentrations between children with chronic gastrointestinal disorders (peptic ulcer disease: p=0.10; functional gastrointestinal disorder associated with peptic ulcer disease: p= 0.710; functional gastrointestinal disorder: p= 0.143) and healthy children. &amp;lt;i&amp;gt;Conclusion&amp;lt;/i&amp;gt;: The diagnostic value of faecal calprotectin as a biomarker in the diagnosis of chronic gastrointestinal disease was not observed in this study. However, the biological parameters assessed were measured only once, and given that their concentrations may vary over time, we recommend a subsequent longitudinal study.

Treatment success in cats with chronic enteropathy is associated with a decrease in fecal calprotectin concentrations.

Feline chronic enteropathies (FCE) are challenging to diagnose and monitor for progression and response to treatment. Fecal calprotectin might be a useful non-invasive marker to evaluate clinical endpoints of therapeutic monitoring in FCE. We evaluated fecal calprotectin concentrations in cats with FCE before and after initiation of treatment comprised of immunomodulation and/or dietary intervention. Included were 17 cats with FCE and 18 healthy controls. Clinical investigation of FCE cases included clinical severity grading (feline chronic enteropathy activity index, FCEAI) in all cats, abdominal ultrasonography in 15 cats, and gastrointestinal biopsies in 6 cats. Fecal calprotectin was measured in samples from 12 cats with FCE before treatment, all 17 FCE cats ≥6 weeks after treatment initiation, and all healthy controls. Fecal calprotectin concentrations in FCE cases before treatment (median: 61 μg/g) were significantly higher than after treatment initiation (median: 15 μg/g; p = 0.0098) and compared to controls (median: 6 μg/g; p = 0.0235) and correlated with the FCEAI scores (ρ = 0.54, p = 0.0316). Fecal calprotectin concentrations after treatment initiation were higher with more severe duodenal/proximal jejunal pathology (ρ = 0.83, p = 0.0427) and shorter intervals between sampling time points (ρ = -0.54, p = 0.0250). Relevant decreases in initially increased fecal calprotectin concentrations are seen in cats with FCE on varying treatment strategies that significantly improve or have remission of clinical signs. This supports the utility of fecal calprotectin as a surrogate biomarker to assess disease severity in FCE cases. Further studies need to evaluate fecal calprotectin concentrations longitudinally in relation to mucosal healing vs. clinical response.

Identifying Immunological Markers for Bowel Cancer.

The role of immunological processes in the pathophysiology of colorectal cancer has received a lot of attention lately and has been extensively researched. Immune processes are significantly regulated by cytokines and antimicrobial peptides (AMP). Numerous studies have demonstrated the significance of cytokines in the prognosis and surveillance of malignant oncological illnesses. In group II, the blood serum concentration of Calprotectin was found to be greater in 13 patients (92.0 %) and lower in 1 patient (8.0 %) compared to control limits (χ = 24.27, p &lt; 0.001). The obtained results show that, in comparison to the control group, the concentration of Calprotectin rises statistically consistently by 3.5 times, with a coefficient of integrity of p &lt; 0.001. According to the data, there is a statistically significant rise in Calprotectin concentration (3.5 times higher than in the control group) with a p-value of less than 0.001. The average mathematical density of this indicator is 3.42 ± 0.48 pg/ml, the minimum density is 0.7 pg/ml, and the maximum thickness is 6.1 pg/ml.

Lower Diet Quality Associated with Subclinical Gastrointestinal Inflammation in Healthy United States Adults

BackgroundHigher diet quality has been associated with lower risk of developing inflammatory bowel disease, but associations between diet and gastrointestinal (GI) inflammation in healthy adults prior to disease onset are understudied. ObjectivesThe purpose of this project was to examine associations between reported dietary intake and markers of GI inflammation in a healthy adult human cohort. MethodsIn a cross-sectional observational trial of 358 healthy adults, participants completed ≤3 unannounced 24-h dietary recalls using the Automated Self-Administered Dietary Assessment Tool and a Block 2014 Food Frequency Questionnaire to assess recent and habitual intake, respectively. Those who provided a stool sample were included in this analysis. Inflammation markers from stool, including calprotectin, neopterin, and myeloperoxidase, were measured by ELISA along with LPS-binding protein from plasma. ResultsRecent and habitual fiber intake was negatively correlated with fecal calprotectin concentrations (n = 295, P = 0.011, 0.009). Habitual soluble fiber intake was also negatively correlated with calprotectin (P = 0.01). Recent and habitual legume and vegetable intake was negatively correlated with calprotectin (P = 0.013, 0.026, 0.01, 0.009). We observed an inverse correlation between recent Healthy Eating Index (HEI) scores and calprotectin concentrations (n = 295, P = 0.026). Dietary Inflammatory Index scores were calculated and positively correlated with neopterin for recent intake (n = 289, P = 0.015). When participants with clinically elevated calprotectin were excluded, recent and habitual fiber, legume, vegetable, and fruit intake were negatively correlated with calprotectin (n = 253, P = 0.00001, 0.0002, 0.045, 0.001, 0.009, 0.001, 0.004, 0.014). Recent total HEI score was inversely correlated with subclinical calprotectin (P = 0.003). ConclusionsHigher diet quality may be protective against GI inflammation even in healthy adults.This trial was registered at clinicaltrials.gov as NCT02367287.

The presence of enteropathy in HIV infected children on antiretroviral therapy in Malawi.

Undernutrition and malnutrition in children in low- and middle-income countries contribute to high mortality rates. Stunting, a prevalent form of malnutrition, is associated with educational and productivity losses. Environmental enteric dysfunction (EED) and human immunodeficiency virus (HIV) infection worsen these conditions. This study seeks to investigate the presence of enteropathy using EED fecal biomarkers in HIV-infected children who are stable on antiretroviral therapy (ART) across various nutritional statuses. By understanding the interplay between EED, HIV, and nutritional status, this study aims to provide insights that can inform targeted interventions to optimize nutritional outcomes in HIV infected children. This study evaluated the levels of alpha-1-antitrypsin, calprotectin and myeloperoxidase in frozen fecal samples from 61 HIV infected (mean age 9.16 ±3.08 years) and 31 HIV uninfected (6.65 ±3.41 years) children in Malawi. Anthropometric measurements and clinical data were collected. The height-for-age z-score (-1.66 vs -1.27, p = 0.040) and BMI-for-age z-score (-0.36 vs 0.01, p = 0.037) were lower in HIV infected children. Enzyme-linked immunosorbent assays were used to measure biomarker concentrations. Statistical tests were applied to compare biomarker levels based on HIV status and anthropometric parameters. Myeloperoxidase, alpha-1-antitrypsin, and calprotectin concentrations did not differ between HIV infected and HIV uninfected children of different age groups. In HIV infected children from 5-15 years, there is no difference in biomarker concentration between the stunted and non-stunted groups. Our study found a higher prevalence of stunting in HIV infected children compared to uninfected children, but no significant differences in biomarker concentrations. This suggests no causal relationship between enteropathy and stunting in HIV infected children. These results contribute to the understanding of growth impairment in HIV infected children and emphasize the need for further research, particularly a longitudinal, biopsy-controlled study.

A green tea extract confection decreases circulating endotoxin and fasting glucose by improving gut barrier function but without affecting systemic inflammation: A double-blind, placebo-controlled randomized trial in healthy adults and adults with metabolic syndrome

Anti-inflammatory activities of catechin-rich green tea extract (GTE) in obese rodents protect against metabolic endotoxemia by decreasing intestinal permeability and absorption of gut-derived endotoxin. However, translation to human health has not been established. We hypothesized that GTE would reduce endotoxemia by decreasing gut permeability and intestinal and systemic inflammation in persons with metabolic syndrome (MetS) compared with healthy persons. A randomized, double-blind, placebo-controlled, crossover trial in healthy adults (n = 19, 34 ± 2 years) and adults with MetS (n = 21, 40 ± 3 years) examined 4-week administration of a decaffeinated GTE confection (890 mg/d total catechins) on serum endotoxin, intestinal permeability, gut and systemic inflammation, and cardiometabolic parameters. Compared with the placebo, the GTE confection decreased serum endotoxin (P = .023) in both healthy persons and those with MetS, while increasing concentrations of circulating catechins (P < .0001) and γ-valerolactones (P = .0001). Fecal calprotectin (P = .029) and myeloperoxidase (P = .048) concentrations were decreased by GTE regardless of health status. Following the ingestion of gut permeability probes, urinary lactose/mannitol (P = .043) but not sucralose/erythritol (P > .05) was decreased by GTE regardless of health status. No between-treatment differences (P > .05) were observed for plasma aminotransferases, blood pressure, plasma lipids, or body mass nor were plasma tumor necrosis factor-α, interleukin-6, or the ratio of lipopolysaccharide-binding protein/soluble cluster of differentiation-14 affected. However, fasting glucose in both study groups was decreased (P = .029) by the GTE confection compared with within-treatment arm baseline concentrations. These findings demonstrate that catechin-rich GTE is effective to decrease circulating endotoxin and improve glycemic control in healthy adults and those with MetS, likely by reducing gut inflammation and small intestinal permeability but without affecting systemic inflammation.

Assessment of the predictive value of plasma calprotectin in the evolution of SARS-Cov-2 primo-infection

BackgroundThe COVID-19 epidemic still calls for anticipation aimed at preventing the overloading of critical care services. With this in mind, the predictive value of easily accessible biomarkers is to be assessed. ObjectiveSecretion of calprotectin is stimulated during an inflammatory process, especially in the cytokine storm. We tried to determine whether early plasma concentration of calprotectin in patients with primary SARS-CoV-2 infection could predict an adverse outcome in cases of COVID-19. MethodsWe included 308 patients with a primary diagnosis of SARS-CoV-2 confirmed by PCR. Heparinized tube samples, collected within the first 24 h of hospitalization, were used for biomarker assays, in which plasma calprotectin was included. Data from the patients' medical records and severity groups established subsequent to diagnosis at the end of hospitalization were collected. ResultsEarly plasma calprotectin concentration is significantly associated with progression to a severe form of COVID-19 in patients with primary infection (Relative Risk: 2.2 [1.6–2.7]). In multivariate analysis, however, it does not appear to provide additional information compared to other parameters (age, GFR, CRP…). ConclusionOur study shows that while an early single blood test for calprotectin could help to predict the progression of a primary SARS-CoV-2 infection, it is not superior to the other parameters currently used in emergency medicine. However, it paves the way for future considerations, such as the interest of this biomarker for high-risk infected patients (immunocompromised individuals…). Finally, the usefulness of early serial measurements of plasma calprotectin to assess progression towards severity of COVID-19 requires further assessment.

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.

FROM RESISTANCE TO RESPONSE: 52 WEEKS OF SUBCUTANEOUS INFLIXIMAB IN REFRACTORY CROHN'S DISEASE PATIENTS AFTER THE MULTIPLE TREATMENT FAILURES

Abstract BACKGROUND Infliximab (IFX), an anti-TNFα monoclonal antibody, has been utilized since the late 1990s as an effective therapeutic agent for the treatment of Crohn's disease (CD). Since 2020, subcutaneous IFX (IFX-SC) has been available for treating CD. This study aimed to conduct a 52-week observation of IFX-SC treatment in refractory CD patients who had failed on at least two previous lines of biologic therapy patients. MATERIALS AND METHODS The study included 32 patients diagnosed with CD who had failed on 2 to 7 previous lines of biological therapy. Observed cohort was monitored at weeks W0, W4, W14, W30, and W52, recording Harvey-Bradshaw Index (HBI) , C-reactive protein (CRP) and fecal calprotectin (FC) concentrations, trough infliximab (TL-IFX) and anti-infliximab (anti-IFX) serum levels. Endoscopic, ultrasonographic and magnetic resonance disease scores (SES-CD, IUS and MaRIA) were determined at baseline and W52. RESULTS 52-week persistence on IFX-SC treatment was recorded in 18 out of 32 patients (56.3%). A significant decrease of HBI (P &amp;lt;0 .0001), CRP (P =0 .0035), FC (P =0.0012), SES-CD (P =0.013), IUS (P =0.0034) and MaRIA (P =0.0261) was observed. TL IFX increased significantly (.0073), and median TL-IFX levels reached 19.75 μg/mL at W52. During the therapy, 8 out of 16 initially anti-IFX positive individuals seroconverted to negative anti-IFX (50 %); no new sensitization to IFX was recorded in the cohort. None of the patients treated with IFX-SC in W52 needed concomitant immune-modifying treatment. Baseline clinical, laboratory, and imaging markers did not demonstrate any predictive value for IFX-SC treatment failure, except for baseline high levels of anti-IFX (P = &amp;lt;0.0001). CONCLUSION In the cohort of refractory CD patients, over half achieved one-year treatment persistence on IFX-SC, displaying a highly favorable trend in all disease activity markers. The IFX-SC treatment appears to be effective and safe; however, further research is needed to identify potential predictors of therapeutic responsiveness. Acknowledgement: This work was supported by the IBD-COMFORT Foundation

P1080 Real-world Study on Early Predictors of Infliximab Treatment Efficacy in Crohn's disease

Abstract Background Infliximab (IFX) can effectively induce and maintain the clinical remission of Crohn's disease (CD). However, a substantial number of CD patients experience primary or secondary nonresponse to IFX during treatment. Therefore, it is essential to identify early predictors of IFX treatment efficacy. Methods This study included 147 CD patients. Based on clinical outcomes, patients were categorized into IFX nonresponse and response group. We collected and compared laboratory data on blood routine examination, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), fecal calprotectin and post-induction IFX drug concentration and antibody levels in both groups. Logistic regression models were employed to identify potential factors associated with the risk of IFX nonresponse. Machine learning using random forest analysis was utilized to quantitatively assess the predictive features for IFX treatment efficacy and ROC curves was used to evaluate the model’s accuracy. Additionally, we performed HE staining and double immunofluorescence staining for CD64 and CD206 on intestinal biopsy tissues obtained before IFX treatment to compare the difference of macrophage subtypes between the nonresponse and response groups. Results Data from both cohorts revealed that patients in the IFX nonresponse group had lower drug concentration (P &amp;lt; 0.001), higher antibody levels (P &amp;lt; 0.001), and increasing ESR during the induction therapy (P &amp;lt; 0.001). Univariate and multivariate Logistic regression models demonstrated that IFX drug concentration and the ratio of ESR before and after induction therapy were associated with the risk of nonresponse. After the induction period, for each unit increase in drug concentration (1 μg/ml), the risk of IFX nonresponse decreased by 23% (RR= 0.77, 95% CI = 0.68-0.89), while each doubling of the ESR ratio after induction was associated with a 1.43-fold increase in the risk of nonresponse (RR= 2.43, 95% CI = 1.48-4.00). After combining data from the two cohorts, random forest machine learning analysis revealed that drug concentration below 1.5 μg/ml and an increase in ESR during induction could predict IFX nonresponse, with ROC curve areas of 0.740 and 0.651, respectively. Furthermore, immunofluorescence staining of intestinal mucosal biopsy tissues before IFX treatment showed a higher proportion of M1-type macrophages in the nonresponse group compared to the response group (P &amp;lt; 0.05). Conclusion Our study suggests that lower post-induction IFX drug concentrations and an increase in ESR during the induction phase are predictive of IFX nonresponse. Additionally, a higher proportion of M1-type macrophages in the intestinal mucosa before IFX treatment is associated with IFX nonresponse.

P951 Efficacy and safety of tofacitinib for the treatment of moderate- severe ulcerative colitis in biologic naïve patients

Abstract Background To assess the rates of clinical response at week 8, biochemical response, steroid-free clinical remission, endoscopic healing and safety data at week 26 of tofacitinib in biologic naive patients with moderate-severe ulcerative colitis (UC). Methods This was a retrospective analysis of prospectively collected data extracted from the notes of biologic naïve patients with moderate-severe UC who were treated with tofacitinib in the last 3 years in 5 Greek IBD centers and who had a follow up of at least 26 weeks after initiation of treatment. Tofacitinib was administered at a dose of 10 mg bid for 8 or 16 weeks followed by a maintenance dose of 5mg bid thereafter. Week-8 or -16 clinical response was defined as the reduction in the partial Mayo score of at least 2 points, without concomitant use of any steroid preparation [budesonide, prednis(ol)one, or methylprednisolone]. Steroid free clinical remission at week 26 was defined as a partial Mayo score of ≤1 points without concomitant use of any steroid preparation. Biochemical response at week 26 was defined as any reduction in fecal calprotectin or plasma C-reactive protein concentrations as compared to their baseline levels.Mucosal healing at week 26 was defined as Mayo endoscopic sub-score of ≤1. A safety list of all reported adverse events was completed. Treatment discontinuation due to adverse events was considered as treatment failure, whereas patients needing escalation of the maintenance dose were also considered as non-responders. Results Overall, 41 patients (26 males), aged (mean, SD) 35.2 (12.7) years and disease duration of mean (SD) 6.5 (4.8) years were included. UC was extensive in 22, left-sided in 17, and proctitis in 2 patients. Clinical response was seen in 31 (75.6%) and 34 (82.9%) patients at week 8 and 12 respectively.Biochemical response and steroid free clinical remission at week 26 were seen in 35 (85.4%) patients. Endoscopic healing was seen in 29 (70.7%) patients. Adverse events,which did not lead to treatment discontinuation, occurred in 5 patients (hyperlipidemia n=3, elevated liver enzymesn=1, herpes zoster n=1). Conclusion In this retrospective real-world ongoing cohort study, tofacitinib demonstrated clinical response at week 8 or 16 and steroid free clinical remission at week 26 in more than 75% of biologic naïve patients with moderate-severe UC with a good safety profile.

P137 Salivary calprotectin: a potential biomarker in inflammatory bowel disease?

Abstract Background Background: Biomarkers are used frequently for evaluation and monitoring of IBD. Fecal calprotectin (FCP) is an already established biomarker in IBD, nevertheless patients often do not feel comfortable with stool manipulation. A saliva sample collection is particularly interesting due to its noninvasiveness and readiness of collection. We aimed to assess if salivary calprotectin (SCP) could be used as a new biomarker to assess disease activity. Methods In this observational cohort study, saliva was collected through the passive drool technique from adult IBD patients. All patients were submitted to a previous oral examination performed by a dentist. Recent history of antibiotic treatment (within the preceding month), proton pump inhibitors or non-steroidal anti-inflammatory drugs were exclusion criteria. Determination of FCP and SCP levels was accomplished using Elia Stool Extraction Kit and Elia Calprotectin 2 test. Intestinal disease activity was assessed with fecal calprotectin levels and the Harvey-Bradshaw Index (HBI) or Partial Mayo score (PMS). Ethical approval was obtained. Results 92 patients (56 with CD and 36 with UC) were included. Clinical characteristics are presented in Table 1. Patients had a median FCP of 45 mg/Kg and a median SCP of 206.5 mg/Kg. No significant correlations between SCP and FCP, CRP (C-reactive protein), ferritin and ESR (erythrocyte sedimentation rate) were found. However, there was a significant correlation between fecal calprotectin and CRP (p&amp;lt;0.001) and ESR (p=0.011). Disease activity scores did not correlate significantly with SCP, although there was a significant correlation between FCP and PMS (p=0.006). IBD patients were stratified based on a composite criterion for inactive disease HBI score &amp;lt;5 for CD or a PMS ≤ 2 for UC, and FCP cutoff value of 150 mg/Kg), with no significant difference in SCP between the two groups, despite the significant difference in FCP (p&amp;lt;0.001). No significant differences between different treatments groups or no treatment in salivary calprotectin concentration were found using Kruskal–Wallis H tests (CD (χ2(4) = 6.211, p = 0.184; UC group (χ2(3) = 1.201, p = 0.753)). 77% of patients with IBD do not have periodontal health. Nonetheless, there was no significant difference in the median SCP value between patients with or without periodontal health. Although the median SCP value was higher in patients with UC without periodontal health, the difference was not statistically significant (0.484). Conclusion SCP does not correlate with FCP and do not represent a reliable biomarker to distinguish disease activity in patients with IBD patients. Moreover, according to our results, it cannot be used as a marker of lack of oral health, namely periodontitis.

P348 Increased pre-treatment faecal calprotectin concentration predicts resistance to ustekinumab induction in ulcerative colitis

Abstract Background Rates of resistance to advanced therapy remain high in ulcerative colitis (UC). Pre-treatment predictors of poor outcomes would provide valuable information for treating clinicians so other therapies could be given or early treatment switches could be considered if response is inadequate. We investigated whether baseline, pre-treatment faecal calprotectin (FCP) can predict resistance to ustekinumab. Methods Clinical outcomes at week 8, including clinical remission, endoscopic healing and mucosal healing were determined in patients enrolled in the UNIFI phase 3 placebo-controlled trial program, investigating the efficacy of ustekinumab for moderate-to-severe UC (GSE206285), in whom FCP concentrations were available at baseline, prior to initiation of treatment. Clinical outcomes were defined in patients with FCP &amp;lt; 250mcg/g, 250 – 999mcg/g, 1000 – 1999mcg/g and &amp;gt;= 2000mcg/g. Chi-squared test was used to assess statistical significance. Area under the receiver operating characteristics curve (AUROC) analyses were used to determine the ability of faecal calprotectin level to predict treatment resistance. Analyses were performed using R 4.2.3 (Vienna, Austria) and GraphPad Prism 10.0.3 (Massachusetts, United States). Results Outcome data and linked faecal calprotectin levels were available for 340 patients. FCP values ranged from 15 – 25249mcg/g. The median FCP value was 1402mcg/g (interquartile range: 600.8 – 2772.0mcg/g). In general, all clinical outcome measures were progressively worse with increasing FCP concentrations. For the respective FCP cut-offs, 22.0%, 19.3%, 11.3% and 6.7% achieved clinical remission; 39.0%, 24.1%, 20.6% and 16.0% achieved endoscopic healing; and 29.3%, 16.9%, 15.5% and 7.6% achieved mucosal healing (Figure 1). ROC analyses revealed that pre-treatment FCP predicts resistance to ustekinumab therapy for all stated outcomes, including clinical remission (AUROC: 0.66, P=0.001), endoscopic healing (AUROC: 0.63, P=0.0013) and mucosal healing (AUROC: 0.65, P=0.0005). Conclusion Increasing concentrations of pre-treatment FCP predicts resistance to ustekinumab therapy in moderate-to-severe UC. Patients with FCP &amp;gt;= 2000mcg/g were significantly less likely than those with FCP &amp;lt;1000 mcg/g to achieve clinical remission or mucosal healing. Since neutrophils are the main producers of FCP, these data build on other emerging data indicating that excessive accumulation of mucosal neutrophils is associated with treatment resistance in IBD.

P371 Calprotectin Testing: A Methods Comparison Study

Abstract Background In conventional laboratory-based Enzyme Linked Immunosorbant Assays (ELISA) for calprotectin measurement, raw stool is returned to and manually processed by testing laboratories. The OCS-Pledia calprotectin test uses the same stool collection device as the OCS-Pledia FIT test used in the UK Bowel cancer screening programme. In brief, individuals sample their stool with a picker and transfer to a preprepared buffered diluent, which is then returned to the laboratory for fully automated analysis. We have previously shown that a stool concentration of &amp;gt;100ug/g measured using the IDK calprotectin ELISA was the optimal cut-off to distinguish IBS from IBD (sensitivity 86%, specificity 90%, positive predictive value 39%, negative predictive value 99%). We undertook a methods comparison study to report the stability, linearity and potential bias of the OCS-Pledia calprotectin assay compared with IDK ELISA. Methods 32 stool samples were collected from people with GI pathology, and homogenised. Samples were prepared for calprotectin testing using IDK and OCS-Pledia less than 4 hours from excretion (mean2.6 [SD]1.3 hrs). Samples were left at room temperature and further extracts taken at 6, 24, 48, 72, and 168 hours. Pairwise analysis of samples across the reporting range was undertaken and linearity and bias assayed by Pearson’s correlation and Bland-Altmann analysis, respectively. Results Calprotectin was stable over one week in both the OCS-Pledia buffered and the IDK ELISA unbuffered stool samples. However, OCS-Pledia results showed lower variance than that of the IDK ELISA, especially at later time points. There was a linear relationship between calprotectin measured with the OCS-Pledia and IDK-ELISA assays (R2=0.85; p&amp;lt;0.0001). The OCS-Pledia calprotectin assay has a positive bias across the reporting range. This led to 40 samples reading elevated calprotectin levels on OCS-Pledia but within normal range on IDK-ELISA. All 40 had colonic inflammation and therefore were false negative IDK-ELISA. Calprotectin concentrations of 600ug/g and 400ug/g measured using the OCS-Pledia assay were equivalent to concentrations of about 250ug/g and 100ug/g measured using the IDK ELISA. Conclusion OCS- Pledia assays for the measurement of calprotectin are likely to superseded conventional ELISAs because they are cheaper, easier to automate and do not involve laboratory staff pre-processing stool samples. Like conventional ELISA assays calprotectin is stable for at least one week. Clinicians will need to be aware, however, of the positive bias across the reporting range of calprotectin and adjust their positivity thresholds.