Introduction

The specific and sensitive biomarkers of inflammatory bowel disease (IBD) had not been found.

Aims & Methods

The aim of this study was to observe the metabolic characteristics of IBD patients and its damp heat syndrome (IBD-DH).
From May 2020 to July 2021 at Affiliated Hospital of Nanjing University of Chinese Medicine, patients with active inflammatory bowel disease (IBD), including damp heat syndrome (IBD-DH) and spleen-deficiency syndrome (IBD-SD), functional diarrhea patients (FD), and healthy volunteers (Con) were recruited. Fasting venous plasma and 2nd urine were collected from all patients and healthy volunteers; Using pseudotargeted metabolomics based on ultra-high performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) and triple-quadrupole mass spectrometry (TQMS).

Results

A total of 60 patients with IBD (30 each in damp heat and spleen deficiency syndrome group), 23 patients with functional diarrhea, and 30 healthy volunteers were recruited in this study. A total of 60 plasma samples (30 IBD-DH and 30 IBD-SD) and 30 urine samples (15 each in IBD-DH and IBD-SD ) were collected for IBD patients; 23 plasma samples and 20 urine samples from FD patients; 30 plasma samples and 15 urine samples from healthy volunteers.
In the IBD group compared with the Con group, 73 and 98 differential metabolites were screened in plasma and urine, respectively. The differential metabolites mainly included acylcarnitine, aromatic amino acid metabolites, glycerophospholipids, amino acids, and glucose metabolism intermediates. Abundance of ACar 16:1, ACar 18:1, ACar 20:4, LPC P-18:0 and malate increased significantly; abundance of PC 33:3, glycocholic acid, hippuric acid, p-cresol and p-cresol sulfate decreased significantly. Differential metabolite ROC analysis suggested L-glutamic acid, ACar 18:1, and Lactic acid as potential diagnostic biomarkers for IBD.
Forty-eight plasma differential metabolites and 69 urinary differential metabolites were obtained in the IBD group compared with the FD group. The differential metabolites mainly included fatty acids, acylcarnitine, aromatic amino acid metabolites, bile acids, and glycerophospholipids. The abundance of ACar 6:0, PC 24:0, 5b-cholestane-3a,7a,12a,24,25-pentanol, and 3-methoxybenzenediol in plasma was significantly decreased; the abundance of glycocholicacid and glycochenodeoxycholic was increased. The abundance of corticosterone, 5-hydroxy-N-formyl-kynurenine and other substances in the urine was significantly decreased. By ROC analysis, ACar 6:0, 5b-cholestane-3a,7a,12a,24,25-pentanol were found to be potential diagnostic markers to differentiate IBD from FD.
28 differential metabolites in plasma and 15 differential metabolites in urine were found .The abundance of 25 substances, including PC 16:1_20:4, PC 18:0_20:4, LPC 16:0-2, LPC 3:1, L-tryptophan, tyramine, and 3-hydroxybutyrate, increased in plasma; the abundance of indolelactic acid was decreased. By ROC analysis, indolelactate, tyramine, L-tryptophan, LPC 16:0-2, PC 38:7-sn1, and itaconic acid were found to distinguish IBD-SD and IBD-DH and were expected to be potential diagnostic biomarkers for IBD-DH.

Conclusion

As an organic lesion closely related to inflammation and immunity, IBD had prominent changes in the abundance of plasma ACar 6:0, 5b-cholestane-3a,7a,12a,24,25-pentanol in comparing with FD, a functional disease of the intestine. In terms of different syndromes, The differential metabolites mainly include aromatic amino acids and glycerophospholipids could be used to distinguish damp heat syndrome from spleen deficiency syndrome.

Disclosure

No Conflict of Interest to be declared

Introduction

A key feature of IBD pathogenesis is response dysregulation of both the innate and adaptive immune system^1,2. Hence specific inflammatory protein profiles may be a promising biomarker approach for diagnosis and personalized therapy in IBD. Serum proteome of IBD, particularly in multi-ethnic Asian patients, remains less defined.

Aims & Methods

We aim to investigate the systemic inflammatory protein profiles in multi-ethnic Asian patients with IBD and compare them to healthy controls.
The study cohort was made up of 92 patients with IBD (50.0% Ulcerative colitis (UC), 43.5% Crohn's disease (CD), 6.5% Unclassified IBD)), and 42 control subjects, who are asymptomatic patients undergoing screening colonoscopy with no endoscopic pathology. Serum protein profiling was performed using the Olink Target 96 Inflammation assay. A partial-least square discriminant analysis was undertaken to identify additional discriminative inflammatory proteins. Univariate t-test analyses, with false discovery rate correction, were also performed to identify proteins unique to either UC or CD.

Results

Participants with IBD were younger (42.0 (±14.7) in UC, 43.2 (±15.1) in CD, p<0.01), with greater representation of South Asian ethnicity (32.5% amongst UC, 19.6% amongst CD, p<0.01) and males (75.0% amongst UC, 69.6% amongst CD, p=0.03), as compared to controls.
We found 18 proteins were differentially abundant amongst IBD patients (p<0.05). Half (n=9) of these inflammatory proteins (AXIN-1, CD8A, CXCL1, EN-RAGE, FGF-23, HGF, IL17A, OSM, TGF-alpha) were elevated in both UC and CD. The other six proteins were elevated only in patients with UC (4E-BP1, CCL11, IL-18R1, IL-20, MMP-10, TRANCE). Of the remaining three, two were less abundant in patients with CD (DNER, SCF) and TNF was elevated only in patients with CD. Of interest, three immunoproteins were differentially abundant in participants with either UC or CD (i.e. CCL11, MMP10, TRANCE).

Molecular functions	Both UC and CD	UC only	CD only	UC vs CD
Cytokine mediated signaling (GO:0019221)	IL17A CXCL1 OSM HGF	CCL11 TRANCE IL20	TNF	CCL11 TRANCE
Positive regulation of protein kinase B signaling (GO:0051897)	FGF23 HGF OSM TGF-alpha	TRANCE	SCF* TNF	TRANCE
Immune response (GO:0006955)	CD8A CXCL1 IL17A OSM	IL-18R1 TRANCE		TRANCE
Inflammatory response (GO:0006954)	CXCL1 EN-RAGE IL17A	CCL11 IL-18R1	TNF	CCL11
MAPK cascade (GO:0000165)	FGF-23 HGF TGF-alpha		SCF* TNF
Others	AXIN1^	MMP-10# 4E-BP1$	DNER*@	MMP-10#

Table1: List of immunoproteins differentially abundant (p<0.05) in varying IBD subtypes, grouped by their key common molecular functions. *indicates that the immunoprotein of interest to be less abundant compared to controls. ^AXIN1 functions - Activation of protein kinase (GO:0032147), WNT signaling process (GO:0016055). ^#MMP-10 function - extracellular matrix organization (GO:0030198). ^$4E-BP1 function - TOR signaling (GO:0031929). ^@DNER function - Notch receptor processing (GO:0007220).

Conclusion

Our pilot study in a multi-ethnic Asian population found distinctive serum protein profile in IBD patients. While some protein changes were shared in both UC and CD, other changes were specific for either UC or CD, suggesting different disease pathways in these two IBD subtypes. We reaffirmed that inflammatory proteins, such as EN-RAGE³, MMP-10⁴ and OSM⁵, were differentially abundant in IBD, consistent with previous reports in predominantly Caucasian cohorts. Further studies with large sample sizes would be required to validate these biomarkers for IBD activity, and prognosis for biologic therapy response.

References

1. Neurath MF. Cytokines in inflammatory bowel disease. Nat Rev Immunol. 2014 May;14(5):329-42.
2. Mahida YR. The key role of macrophages in the immunopathogenesis of inflammatory bowel disease. Inflamm Bowel Dis. 2000;6:21–33.
3. Foell D, Kucharzik T, Kraft M, et al. Neutrophil derived human S100A12 (EN-RAGE) is strongly expressed during chronic active inflammatory bowel disease. Gut 2003;52:847-853.
4. Fonseca-Camarillo G, Furuzawa-Carballeda J, Martínez-Benitez B, et al. Increased expression of extracellular matrix metalloproteinase inducer (EMMPRIN) and MMP10, MMP23 in inflammatory bowel disease: Cross-sectional study. Scand J Immunol. 2021 Jan;93(1):e12962.
5. Sare Verstockt, Bram Verstockt, Kathleen Machiels, et al. Oncostatin M Is a Biomarker of Diagnosis, Worse Disease Prognosis, and Therapeutic Nonresponse in Inflammatory Bowel Disease. Inflamm Bowel Dis. 2021 Oct 18;27(10):1564-1575.

Introduction

Both patients and clinicians would benefit from less invasive means than endoscopy for detection of gut inflammation in inflammatory bowel disease (IBD), such as faecal or serological biomarkers.

Aims & Methods

The aim of this study was to investigate the presence of the neutrophilic proteins: calprotectin (CP), myeloperoxidase (MPO), neutrophil gelatinase-associated lipocalin (NGAL) and the eosinophilic protein: eosinophil-derived neurotoxin (EDN) in faecal and serum samples from IBD patients with ulcerative colitis (UC) and Crohn’s disease (CD) in relation to disease activity and intestinal inflammation localization. Their diagnostic potential in IBD was studied using irritable bowel syndrome (IBS) patients as controls.
Faecal (f) and serum (s) samples from 97 IBD (median: 38y, range 18-79y) and 100 IBS (median: 36y, range 18-75y) patients from the outpatient Gastroenterology Clinic, Uppsala University Hospital were included in the study. Active disease was defined as having a Partial Mayo score ≥ 2 (UC) or Harvey-Bradshaw score ≥5 (CD). Disease localization was obtained from patient journals.
CP and EDN were measured by commercial EliA and ImmunoCAP assays, respectively. MPO and NGAL were measured with in-house research assays based on the ImmunoCAP technology. All analyses were done using the automated Phadia 250 instrument.

Results

All four biomarkers were elevated in IBD compared to IBS in faecal samples (p<0.001) and serum (p<0.01), and most biomarkers were also elevated in the separate UC and CD groups (Table 1). Faecal EDN were higher in CD compared to both UC (p=0.016) and IBS.
Table 1. Biomarker levels in UC and CD patients in comparison to IBS patients

	UC N=59	CD N=38	IBS N=100	p-value (UC vs. IBS)	p-value (CD vs. IBS)
fCP	305.8 mg/kg	165.8 mg/kg	16.51 mg/kg	<0.0001	<0.0001
fMPO	3.74 mg/kg	2.42 mg/kg	0.10 mg/kg	<0.0001	<0.0001
fNGAL	7.30 mg/kg	6.78 mg/kg	2.36 mg/kg	<0.0001	<0.0001
fEDN	0.50 mg/kg	1.79 mg/kg	0.29 mg/kg	0.049	<0.0001
sCP	4186 µg/L	4124 µg/L	3037 µg/L	0.0145	ns
sMPO	291.6 µg/L	291.2 µg/L	151.3 µg/L	0.0006	0.0038
sNGAL	240.2 µg/L	239.5 µg/L	162.2 µg/L	<0.0001	0.0004
sEDN	29.07 µg/L	24.54 µg/L	19.4 µ/L	0.0020	ns

Four biomarkers were elevated in active UC vs remission: fCP (610.9 mg/kg vs 45.5 mg/kg, p=0.0180), fMPO (6.84 mg/kg vs 1.30 mg/kg, p=0.0479), sCP (4599 µg/L vs 3128 µg/L, p=0.0194) and sNGAL (298.3 µg/L vs 189.3 µg/L p=0.0012). No association was observed between the biomarkers and disease activity in CD.
Patients with extensive UC had significantly higher levels, compared to patients with left-sided UC, of fCP (851.6 mg/kg vs 148.3 mg/kg, p=0.0135), fMPO (17.67mg/kg vs 2.84 mg/kg, p=0.0493) and fEDN (1.34 mg/kg vs 0.36 mg/kg, p=0.0146). None of the biomarkers were associated with disease localization in CD.

Conclusion

Faecal and serum CP, MPO, NGAL and EDN may be used as diagnostic biomarkers to differentiate patients with IBD from IBS. Our study indicates that fMPO may be used as an alternative to fCP as disease activity marker in UC, and that sCP and sNGAL are promising novel serum markers for disease activity. In addition to the neutrophil markers, fEDN could be of value for characterization of extensive disease in UC patients. The higher fEDN levels in CD compared to UC observed in the present study indicates an important role of activated eosinophils in the clinical manifestation of CD.
The biomarkers MPO, NGAL and EDN measured both in faecal and serum could, in addition to CP, potentially aid in the clinical decision-making in IBD.

Disclosure

H Ekoff, N Rydell and R Movérare are employed by Thermo Fisher Scientific.

Introduction

Inflammatory bowel disease (IBD) is a chronic multi-factorial disease characterized by inflammation of the gastrointestinal tract. Currently, the mechanisms underlying the disease are far from being elucidated. Thus, the study of proteins involved in its pathogenesis would allow further insights into the molecular mechanisms underlying IBD.

Aims & Methods

The serum and intestinal mucosa (ileum and left colon) proteomic profiles of patients with Crohn´s disease (CD) and ulcerative colitis (UC) and healthy controls (HC) were analyzed through label-free relative quantitative proteomic profiling using nLC MS/MS. Data mining and pattern recognition techniques were performed to identify hidden relationships that are not detectable using classical linear classifiers, and thus identify potential markers able to discriminate between the different study groups. Six candidate biomarkers were selected for further validation using enzyme-linked immunosorbent assay (ELISA) and immunohistochemistry (IHC) in serum and intestinal tissue samples, respectively.

Results

Comparison of serum proteins between UC patients and HC revealed statistically lower levels of protein 1 and 2 and higher levels of protein 3. The comparison of potential biomarkers between CD and HC group showed lower levels of protein 1 and higher levels of protein 3. In addition, protein 4 was differentially upregulated in CD patients compared to UC. Regarding the intestinal biopsies, protein 5 showed higher intensity in the IHC staining of ileum from CD patients compared to HC, whereas protein 6 was significantly decreased in left colon and ileum from CD and UC patients compared to HC. These proteins are involved in thyroxine transport, regulation of chemotactic chemokine activity, inflammatory processes, triglyceride homeostasis, oxidative stress and regulation of NF-kappa-B activation in the cytosol.

Conclusion

In this study, we have identified a panel of six potential biomarkers that could help to elucidate mechanisms involved in IBD pathogenesis. Their roles in the pathophysiology need to be clarified in further experiments.

Introduction

Inflammatory bowel disease (IBD) and atopic diseases, namely asthma, atopic dermatitis (AD), and atopic rhinoconjunctivitis (AR) show a rising prevalence worldwide and share some genetic and epidemiological risk factors. Consequently, observational studies have explored the potential association between IBD and atopic diseases, with some conflicting data.

Aims & Methods

The objective of this study was to systematically review and summarize the current evidence on the co-occurrence of IBD and these atopic diseases.
We searched Medline, Embase, Web of Science and CENTRAL (from inception to August 14, 2022) to identify observational studies on the incidence or prevalence of IBD in atopic diseases (asthma, AD; AR) and vice versa.

Results

We included 23 observational studies (17 cohort, 4 case-control, 2 cross-sectional) on the association between IBD and asthma, comprising approximately 2 million patients; 17 of them showed a positive association and only one study showed a negative association. Nineteen studies (12 cohort, case-controls, 4 cross-sectional) on the association between IBD and AD were included, with approximately 2,6 million patients; 16 showed a positive association and 3 showed no association. We included 4 cohort studies on the association between IBD and AR, covering approximately 2,2 million patients which all showed a positive statistically significant association.

Conclusion

Published literature supports that IBD is associated with asthma, AD and AR, and vice versa. These results may increase gastroenterologists’ awareness for these diagnoses so that timely management can be initiated. Additional research is needed to determine if one disease influences the risk of developing the other or if the frequent co-occurrence of these diseases results from shared genetic, environmental and microbial factors. As far as the author’s know, this is the first systematic review that reports the association between IBD and the three main atopic diseases.

Introduction

Inflammatory Bowel Disease (IBD), comprising Crohn's disease (CD) and ulcerative colitis (UC), is a chronic inflammatory condition affecting the gastrointestinal tract. Although primarily associated with intestinal symptoms, IBD has also been linked to various extraintestinal complications, including liver fibrosis (LF). Additionally, metabolic-associated steatotic liver disease (MASLD), a common liver condition driven by metabolic risk factors such as obesity and insulin resistance, could intersect with IBD, given its systemic nature.
While both LF and MASLD are prevalent among the general population, their incidence and associated risk factors in IBD patients remain underexplored. Understanding these liver-related complications is crucial for developing effective screening and management strategies for patients with IBD.

Aims & Methods

We aimed to assess the prevalence of LF and MASLD in IBD patients compared to matched controls. In this cross-sectional, case-control study, we enrolled consecutive IBD patients from an IBD referral center and matched controls from the general population based on age, sex, type 2 diabetes (T2D) status, and body mass index (BMI) in a 1:1 ratio. Liver fibrosis and MASLD were confirmed through shear-wave elastography (SWE) measurements of stiffness and attenuation coefficient. Potential risk factors were analyzed using multivariate logistic regression.

Results

We included 378 participants, comprising 200 IBD patients (106 with CD and 94 with UC) and 178 controls. There were no statistically significant differences regarding distribution by gender, age, T2D status and BMI. The prevalence of LF (SWE ≥ 6.78 kPa) and advanced LF (SWE ≥ 9.15 kPa) was 42.5% and 16.0%, respectively, in IBD patients (48.1% in CD vs. 36.2% in UC; p=0.088) and 28.1% and 9.0%, respectively, in the control group (p<0.05). For UC, history of complicated disease (OR 7.5, CI95% 1.2-46.2 p<0.05) and multiple hospitalizations due to acute disease (OR 5.6, CI95% 1.3-24.8; p<0.05) were significant risk factors. As for CD, previous hospitalizations (OR 9.7, CI95% 1.4-65.8; p<0.05) and heavy smoking habits (OR 4.9, CI95% 2.0-12.4; p<0.001) were the main risk factors. Extraintestinal manifestations, higher fecal calprotectin level at the time of liver stiffness measurement and latest endoscopic activity were not associated with presence of LF. MASLD was not significantly different between IBD and control group (42.0% vs. 51.7%, respectively; p>0.05). Higher BMI, higher waist circumference, higher abdominal wall thickness and metabolic syndrome were significant risk factors for MASLD (p<0.001).

Conclusion

Our case-control study demonstrates that patients with IBD have a higher prevalence of liver fibrosis compared to matched controls, with significant risk factors including a history of complicated disease, multiple hospitalizations, and heavy smoking habits. Conversely, the prevalence of MASLD does not significantly differ between IBD patients and controls, suggesting that metabolic factors might play a more substantial role in MASLD risk. Given these findings, it is critical for clinicians to implement routine liver fibrosis surveillance in IBD patients, especially in those with identified risk factors. Proactive management strategies aimed at reducing risk factors, such as smoking cessation and minimizing hospitalizations through effective disease management, could mitigate liver fibrosis risk in this population. These insights emphasize the need for integrated care approaches that address both IBD-related complications and associated liver health.

Introduction

Patient-reported outcomes (PROs) are pivotal in assessing treatment efficacy, delivering patient-centered care, and estimating the burden for inflammatory bowel diseases (IBD), including ulcerative colitis (UC) and Crohn’s disease (CD).

Aims & Methods

We aimed to investigate PROs at IBD diagnosis, including associated factors.
Since May 1^st, 2021, all adult and pediatric patients with incident IBD within a catchment area encompassing 20% of the Danish population were enrolled in the prospective population-based Copenhagen IBD Inception Cohort.¹ Upon diagnosis, all adult patients diagnosed between May 2021 and May 2023 were asked to report PROs including Short inflammatory Bowel Disease Questionnaires (SIBDQ), IBD-Disability Index (IBD-DI), and Functional Assessment of Chronic Illness Therapy-Fatigue (FACIT-F). Symptoms were evaluated using Memorial Symptom Assessment Scale, IBD Symptom Inventory, and Mayo Assessment of Functional Gastrointestinal Disease. Multivariable logistical analysis adjusting for gender, age, and disease phenotype was conducted (adjusted odds ratio, aOR (95% confidence interval)).

Results

The population consisted of 203 and 116 patients with UC and CD (66% and 58% of the original cohort), respectively, who completed the PROs questionnaires within a median of 1.2 (IQR 0.3–3.0) months from diagnosis. The only baseline difference between participants and non-participants was a higher proportion of females with UC in the former group (60% vs. 44%, p<0.01).
In total, 160 (79%) and 99 (85%, p=0.18) patients with UC and CD, respectively, reported moderate to severe affection of at least one PRO, while 44% and 64% (p<0.01), respectively, reported moderate to severe affection of at least two PROs.
Specifically, a higher proportion of patients with CD reported moderately to severely impaired quality of life (QoL) (96 (82.8%)) compared to UC (141 (69.5%), p<0.01). Of those, 33 (82.5%) and 41 (56.9%), respectively, reported simultaneously moderate to severe fatigue and disability (p=0.48), while 19 (19.8%) and 27 (19.1%, p=0.90), respectively, reported moderate to severe QoL and fatigue but not disability. In addition, among 71 (35.0%) and 52 (44.8%) with UC and CD, respectively, reporting moderate to severe fatigue (p=0.08), all but three patients with UC had moderate to severe QoL, while 57.6% and 63.5%, respectively, reported moderate to severe disability. Accordingly, FACIT-F correlated strongly with SIBDQ in both UC (Pearson correlation coefficient (PCC) 0.76 (0.70-0.82) and CD (PCC 0.84 (0.78-0.89).
The most frequent symptoms of UC were bloody stool (88%), lack of energy (82%), and abdominal pain (78%), whereas those of CD were lack of energy (86%, p=0.36) and abdominal pain (84%, p=0.17). These symptoms as well as bowel urgency (46% vs. 43%, p=0.60) were equally common in UC and CD, while bloody stool was less frequent in CD (54%, p<0.01). Finally, bowel urgency was linked to moderate to severe disability in UC (aOR=4.01 (1.11;14.51)), but not QoL or fatigue, which was confirmed in sensitivity analysis of proctitis.

Conclusion

Our prospective population-based inception cohort study highlights a considerable burden of UC and CD at the time of diagnosis, with moderate to severe impairment of PROs in most patients. In addition, we observed a clustering of impaired PROs in half of the patients, underscoring the interconnectedness of PRO metrics and symptoms. These findings emphasize the importance of tight monitoring of PROs and symptoms in clinical practice, allowing timely interventions.

References

1. Attauabi M, Madsen GR, Bendtsen F, et al. Influence of Genetics, Immunity and the Microbiome on the Prognosis of Inflammatory Bowel Disease (IBD Prognosis Study): the protocol for a Copenhagen IBD Inception Cohort Study. BMJ Open. 2022;12(6):e055779. doi:10.1136/bmjopen-2021-055779

Disclosure

Mohamed Attauabi: None
Gorm Roager Madsen: Personal fees from Tillotts
Flemming Bendtsen: Tillotts, Ferring
Jakob Benedict Seidelin: has received research grants from Takeda, Janssen, the Danish Research Council, and the Capital Region Denmark, and is national coordinator of studies from AbbVie, Arena Pharmaceuticals, Ely Lilly, and Boehringer Ingelheim.
Johan Burisch: reports grants and personal fees from AbbVie, grants and personal fees from Janssen-Cilag, personal fees from Celgene, grants and personal fees from MSD, personal fees from Pfizer, grants and personal fees from Takeda, grants and personal fees from Tillots Pharma, personal fees from Samsung Bioepis, grants and personal fees from Bristol Myers Squibb, grants from Novo Nordisk, personal fees from Pharmacosmos, personal fees from Ferring, personal fees from Galapagos, outside the submitted work.