Serum Leucine-rich Alpha-2 Glycoprotein Research Articles

Efficacy of serum leucine-rich alpha-2 glycoprotein in predicting findings of Crohn's disease small bowel lesion in capsule endoscopy.

Small bowel capsule endoscopy (SBCE) is an evaluation method for small bowel (SB) lesions in Crohn's disease (CD). However, the relationship between SBCE findings and the serological biomarker leucine-rich alpha-2 glycoprotein (LRG) remains unclear. We aimed to establish appropriate cutoff values of LRG to predict the presence of SB lesions in CD through SBCE. Patients with CD with SB lesions who had undergone SBCE and LRG measurements 1 month before and after the SBCE were included. The LRG values for ulcers ≥0.5 cm and other inflammatory lesions noted in SBCE were determined using the Youden Index, and the sensitivity and specificity were calculated. Additionally, the correlation between the SBCE scores (CD Activity in Capsule Endoscopy) and LRG values was evaluated. Forty patients without active colorectal lesions were included in the study. When the cutoff value of LRG for SB ulcers ≥ 0.5 cm was set at 14 μg/mL, the sensitivity was 92.3%, specificity was 81.5%, positive predictive value (PPV) was 70.6%, and negative predictive value (NPV) was 95.7%. In contrast, an LRG cutoff value of 12 μg/mL without inflammatory findings had a sensitivity of 91.7%, specificity of 82.1%, PPV of 68.8%, and NPV of 95.8%. CD Activity in Capsule Endoscopy correlated well with LRG values (Spearman's rank correlation coefficient ρ = 0.681, P< 0.001). An LRG cutoff value of 14 μg/mL may be useful in predicting the presence of SB ulcers ≥ 0.5 cm, and an LRG cutoff value of 12 μg/mL may be useful in predicting the absence of SB inflammatory findings.

USEFULLNESS OF SERUM LEUCINE-RICH ALPHA2-GLYCOPROTEIN AND FECAL CALPROTECTIN ASSURROGATE MARKERS IN ULCERATIVE COLITIS

Abstract BACKGROUND AND AIM Serum Leucine-rich alpha-2 glycoprotein (LRG) was identified as a novel biomarker for rheumatoid arthritis and IBD by using a proteomics approach. Several studies have suggested that serum LRG levels and fecal calprotectin (fCal) were correlated with clinical activities in patients with ulcerative colitis (UC). We compared utility of these biomarkers for monitoring disease activity in UC. METHODS A single-center observational study was conducted at Kyushu University Hospital. A total of 101 patients who underwent colonoscopy during the period from February to December 2021 were enrolled. The associations between endoscopic and histological activity and biomarkers were investigated. Endoscopic activity was defined as Mayo endoscopic score (MES) of 1 or less for mucosal healing and 0 for complete mucosal healing. For histological activity (n=90), Geboes score of 2 or less was defined as histological remission. RESULTS Subjects ranged in age from 16 to 80 years (35 males and 66 females). There were 63 cases of total colitistype, 32 cases of left-sided colitis type, and 6 cases of proctitis type. The MES at enrollment were as follows: MES 0 in 41 cases, MES 1 in 33 cases, MES 2 in 19 cases, and MES 3 in 8 cases. In comparison between the mucosal healing and non-mucosal healing groups, LRG was significantly lower in the mucosal healing group (p&amp;lt;0.0001). The correlation coefficient of LRG with MES was r=0.614 (p&amp;lt;0.0001), which was higher than that of fCal, r=0.414 (p&amp;lt;0.0001). In ROC analysis with mucosal healing as the outcome, the AUC and cut-off value of LRG were 0.781 and 17.9 μg/ml, respectively, and for fCal were 0.850 and 396 μg/g, respectively. In the ROC analysis with complete mucosal healing as the outcome, the AUC for LRG was 0.690, which was lower than the AUC of 0.846 for fCal . When compared by histological remission, LRG was lower in the histological remission group (p&amp;lt;0.001). In the ROC analysis with histological remission as the outcome, the AUC for LRG was 0.722 (cutoff value 14.2 μg/ml) and for fCal was 0.837 (cutoff value 119 μg/g). CONCLUSION Both LRG and fCal are valuable biomarkers reflecting disease activity in UC.

P660 Serum Leucine-rich Alpha-2 Glycoprotein Can be a Biomarker for Selecting Anti-Cytokine Biologics in Patients with Inflammatory Bowel Disease: A Multicentre Prospective Cohort Study

Abstract Background Serum leucine-rich alpha-2 glycoprotein (LRG) is a biomarker reflecting endoscopic activity in patients with inflammatory bowel disease (IBD). However, it remains unclear whether serum LRG can predict the effectiveness of anti-cytokine biologics (biologics) in patients with IBD. This study aimed to evaluate whether serum LRG could predict the effectiveness and serum trough concentrations of biologics in patients with IBD. Methods This was a multicentre prospective cohort study including patients with IBD (including ulcerative colitis [UC] or Crohn’s disease [CD]) who received the biologics [ustekinumab (UST), anti-tumor necrosis factor (anti-TNF)] from January 2019 to March 2023 at 15 hospitals participating in the Osaka Gut Forum. The effectiveness of biologics was evaluated by clinical remission (CR) at week 8. We defined CR as a partial Mayo score of 2 or lower, with each subscore of 0 or 1 for UC and a CD activity index of &amp;lt; 150 for CD. Factors associated with CR at week 8 such as backgrounds, disease activities and concomitant medications at week 0 were analyzed by Cox proportional hazards model. For each biologic, we compared the effectiveness of biologics in the high LRG group with that in the low LRG group divided by the median serum LRG levels at week 0 (cut-off = 18.2 μg/mL). Results A total of 184 patients with IBD (UC, 80; CD, 104) were enrolled (UST/ anti-TNF, 119/ 65; biologic exposure, 31.5%; median disease duration, 6 years [Interquartile range (IQR) 1-14]). Median serum LRG levels at week 0 and serum C-reactive protein levels at week 0 were 18.2 μg/mL [IQR 12.5-28.1] and 0.19 mg/dL [IQR 0.03-0.77], respectively. At week 0, 63 (34.2%) and 64 (34.8%) patients concomitantly received corticosteroids and immunomodulators, respectively. In 184 patients with IBD, multivariate analysis revealed that serum LRG level at week 0 &amp;lt; 18.2 μg/mL was extracted as a significant factor for CR at week 8 (Odds ratio: OR 2.70, 95% confidence interval: CI 1.22-5.96). In patients who received UST, the proportion of CR at week 8 in the low-LRG group (76.9%) was significantly higher than that in the high-LRG group (59.3%, P = 0.038). In patients who received anti-TNF, however, the proportion of CR in the low-LRG group (84.6%) was not differ from that in the high-LRG group (82.1%, P = 0.781). Median serum trough concentrations of UST at week 8 in the low-LRG group (10.9 μg/mL, IQR 6.7-13.4) was significantly higher than that in the high-LRG group (5.3 μg/mL, IQR 2.4-8.3, P &amp;lt; 0.001). Conclusion Serum LRG could predict the effectiveness and serum trough concentrations of UST and be a biomarker for selecting biologics in patients with IBD.

Significance of Serum Leucine-rich Alpha-2 Glycoprotein as a Diagnostic Marker in Pediatric Inflammatory Bowel Disease.

Serum leucine-rich alpha-2 glycoprotein (LRG) has been utilized for adult inflammatory bowel disease (IBD); however, its efficacy in pediatric IBD remains unknown. The aim of this study was to compare the diagnostic accuracy of serum LRG for pediatric IBD with that of current inflammatory markers, erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). This retrospective case-control study included pediatric patients, aged <16 years, who underwent colonoscopy and/or esophagogastroduodenoscopy between April 2017 and March 2022. All eligible patients were divided into two groups: patients with IBD, diagnosed with ulcerative colitis and Crohn's disease, and non-IBD controls. The optimal cut-off value of serum LRG for IBD diagnosis was determined from receiver operating characteristic analysis, and diagnostic accuracy of serum LRG was compared to serum ESR and CRP. A total of 53 patients (24 with IBD and 29 non-IBD controls) met the inclusion criteria. The cut-off value of serum LRG for IBD diagnosis was determined to be 19.5 μg/ml. At this cut-off value, serum LRG had a positive predictive value (PPV) of 0.80 and negative predictive value (NPV) of 0.88. In contrast, PPV and NPV were 0.78 and 0.70 for serum ESR and 0.82 and 0.72 for serum CRP, respectively. Serum LRG can be a potential diagnostic marker for pediatric IBD, with higher diagnostic accuracy than that of the conventional serum markers ESR and CRP.

Biomarkers for Monitoring of Changes in Disease Activity in Ulcerative Colitis.

In recent years, various biomarkers of ulcerative colitis (UC) have emerged; however, few studies have simultaneously examined the utility of multiple biomarkers for monitoring disease activity. Additionally, serum leucine-rich alpha-2 glycoprotein (LRG), a new biomarker, may show a blunt response to anti-TNF antibody therapy. This prospective study explored effective biomarkers that could monitor disease activity changes in patients with UC. In addition, we examined the effect of anti-TNF antibody therapy on changes in LRG. Blood and stool samples were collected twice from patients with UC: at baseline and at least 8 weeks later. Changes in serum LRG, interleukin (IL)-6, prealbumin (pre-Alb), high-sensitivity C-reactive protein (hs-CRP), CRP, and fecal calprotectin (FC) were measured and correlated with changes in disease activity. The relationship between anti-TNF antibody therapy and LRG levels was also examined in patients with the same disease activity. Forty-eight patients with UC (96 samples) were analyzed. ΔLRG and ΔIL-6 correlated strongly with the change in the partial Mayo (pMayo) score between the two time points (ΔpMayo) (r = 0.686, 0.635, respectively). In contrast, FC and IL-6 were particularly accurate predictors of clinical remission, and their area under the curves (AUCs) were significantly higher than that of CRP (AUC: 0.81, 0.76 vs. 0.50; p = 0.001, 0.005). No association was found between the administration of anti-TNF antibody preparations and the LRG values. Correlations were found between changes in UC disease activity and LRG, IL-6, pre-Alb, hs-CRP, CRP, and FC. LRG reflects disease activity during anti-TNF antibody therapy.

Combined serum albumin, fecal immunochemical test, and leucine-rich alpha-2 glycoprotein levels for predicting prognosis in remitting patients with ulcerative colitis

This study investigated the usefulness of serum leucine-rich alpha-2 glycoprotein (LRG) and fecal immunochemical tests (FIT) for predicting relapse in patients with ulcerative colitis (UC). Data of 194 patients tested for LRG between January 2020 and June 2022 were retrospectively collected and clinical characteristics were recorded. LRG was strongly correlated with CRP levels and it had a moderately negative correlation with albumin levels, whereas FIT was not significantly correlated with either CRP or albumin levels. Furthermore, the median serum albumin and FIT were significantly different between patients with or without clinical relapse; while the LRG level was not associated with clinical relapse. Although LRG is not an independent factor for predicting clinical relapse, the cumulative remission rate was significantly higher in patients with higher albumin than in those with lower albumin. Furthermore, the combination of FIT and albumin was useful for predicting for relapse, patients with higher FIT and lower albumin tended to have higher relapse rates than those with both lower FIT and albumin and those with lower FIT and higher albumin. Our study indicated that serum albumin level is useful for predicting relapse, even in remitting outpatients. Although LRG is not an independent factor for predicting clinical relapse, it is useful for identifying patients that are likely to relapse when combined serum albumin or FIT results.

Serum leucine-rich alpha-2 glycoprotein levels for predicting active ultrasonographic findings in intestinal lesions of patients with Crohn's disease in clinical remission.

This study aimed to investigate the cutoff value of leucine-rich alpha-2 glycoprotein (LRG) in predicting active intestinal ultrasonography (IUS) findings in patients with Crohn's disease (CD) in clinical remission. Data were retrospectively collected from patients with CD evaluated using LRG and undergoing IUS from September 2020 to August 2022. Patients with a Harvey-Bradshaw Index of ≤4 were included and those who underwent intestinal resection were excluded. Bowel wall thickness and stratification and blood flow signal using superb microvascular imaging (SMI) were used to assess ultrasonography findings. SMI signals were categorized into 4 grades following the Limberg score. Receiver operating characteristic curves were constructed and the area under the curve was calculated to determine the LRG cutoff values for predicting active IUS findings and were compared with those of C-reactive protein. This study included 213 patients. The LRG cutoff values to predict active bowel wall thickness, loss of bowel wall stratification, and SMI of ≥1, ≥2, and 3 were 14.6 μg/mL, 14.6 μg/mL, 14.6 μg/mL, 14.6 μg/mL, and 16.9 μg/mL, respectively, with significantly higher areas under the curve in SMI of ≥1 and 3 than in C-reactive protein. The best LRG cutoff value for predicting active IUS findings was 14.6 μg/mL in patients with CD in clinical remission, suggesting that LRG is better than C-reactive protein for detecting active IUS findings in CD.

Systematic Review and Meta-Analysis of the Use of Serum Leucine-Rich Alpha-2 Glycoprotein to Assess Crohn's Disease Activity.

Although fecal calprotectin is the most widely used biomarker for assessing Crohn's disease activity, serum leucine-rich alpha-2 glycoprotein has recently attracted attention, especially in Japan. Here we performed a systematic review and meta-analysis of serum leucine-rich alpha-2 glycoprotein to obtain evidence for its accuracy in assessing Crohn's disease activity. On February 1, 2023, we performed searches of PubMed, Web of Science, and CENTRAL. The Prospero number is CRD42023396034. The primary outcomes were the sensitivity and specificity of serum leucine-rich alpha-2 glycoprotein for assessing Crohn's disease activity. We used a bivariate generalized linear mixed model, assuming a binomial distribution at the test level and a bivariate normal distribution at the between-test level. We selected 9 studies involving 797 individuals in our systematic review. Regarding the primary outcomes, the synthesized sensitivity and specificity of serum leucine-rich alpha-2 glycoprotein were 77.0% (95% confidence interval, 67.8% to 84.2%) and 81.1% (95% confidence interval, 72.6% to 87.4%), respectively. The area under the curve was 0.86, and the partial area under the curve was 0.78. Regarding between-study heterogeneity, both the I2 value by Zhou and Dendukuri approach and the I2 value by Holling sample size-adjusted approaches were 0%. Our systematic review and meta-analysis of serum leucine-rich alpha-2 glycoprotein demonstrated its accuracy in assessing Crohn's disease activity. Further studies are needed to demonstrate its clinical utility and clinical validity.

Serum leucine-rich alpha-2 glycoprotein and calprotectin in children with inflammatory bowel disease: A multicenter study in Japan.

Serum leucine-rich alpha-2 glycoprotein (LRG) and calprotectin have been studied as disease activity markers in adults with inflammatory bowel disease (IBD). We evaluated them in pediatric IBD patients. Subjects under 17years old undergoing care at 11 Japanese pediatric centers were retrospectively assigned to 3 groups representing Crohn's disease (CD), ulcerative colitis (UC), and normal controls (NC) with irritable bowel syndrome or no illness. Serum LRG and calprotectin were measured using commercial enzyme-linked immunosorbent assay kits. We enrolled 173 subjects, including 74 with CD, 77 with UC, and 22 NC. Serum LRG concentrations in active CD (median, 200μg/mL) were significantly greater than in remission (81μg/mL; P<0.001) or NC (69μg/mL; P<0.001). Serum calprotectin concentrations in active CD (2941ng/mL) also were significantly greater than in remission (962ng/mL; P<0.05) or NC (872ng/mL; P<0.05). Serum LRG concentrations in active UC (134μg/mL) were significantly greater than in remission (65μg/mL; P<0.01) but not significantly greater than in NC (69μg/mL); serum calprotectin concentrations in active UC (1058ng/mL) were not significantly different from those in remission (671ng/mL) or NC (872ng/mL). In receiver operating characteristic analyses of LRG, calprotectin, C-reactive protein, and erythrocyte sedimentation rate for ability to distinguish active IBD from remission, CD and UC showed areas under receiver operating characteristic curves for LRG (0.77 and 0.70, respectively), exceeding those for calprotectin, C-reactive protein, or erythrocyte sedimentation rate. In pediatric IBD, serum LRG may better reflect disease activity than serum calprotectin, particularly in CD.

Usefulness of Serum Leucine-Rich Alpha-2 Glycoprotein as a Surrogate Marker of Small Bowel Mucosal Injury in Crohn’s Disease

Introduction: Although the importance of mucosal healing has been suggested in Crohn’s disease, it is difficult to repeat endoscopy, especially for the entire small bowel. Recently, serum leucine-rich alpha-2 glycoprotein (LRG) has been used as a surrogate marker of endoscopy. However, few studies have investigated a correlation between LRG and mucosal injury of the entire small bowel. Methods: We retrospectively analyzed the clinical data of 30 patients with Crohn’s disease from June 2020 to August 2022 at Yamaguchi Red Cross Hospital. All the patients were surveyed through the gastrointestinal tract by esophagogastroduodenoscopy, total colonoscopy, and capsule endoscopy (CE). Subjects with mucosal injury only in the small bowel were selected. Then, we assessed the relationship between serum biomarkers (LRG, C-reactive protein [CRP], hemoglobin, albumin) and small bowel mucosal injury scores (Lewis score [LS], Capsule Endoscopy Crohn’s Disease Activity Index [CECDAI], and Crohn’s Disease Activity in Capsule Endoscopy [CDACE]) calculated by CE. Results: LRG and CRP were significantly correlated with small bowel mucosal injury scores (LS, CECDAI, CDACE) (p < 0.05, Spearman’s rank correlation coefficient). The degree of correlation was greater for LRG than for CRP. Conclusions: LRG is a useful surrogate marker that closely reflects small bowel mucosal injury in the entire small bowel.

Optimal Use of Serum Leucine-Rich Alpha-2 Glycoprotein as a Biomarker for Small Bowel Lesions of Crohn’s Disease

Introduction: A large proportion of small bowel lesions in Crohn’s disease (CD) may exist beyond the reach of ileocolonoscopy and there is no gold standard imaging modality to screen them, suggesting the need for optimal biomarkers. We aimed to compare the usefulness of C-reactive protein (CRP), faecal calprotectin (FC), and leucine-rich alpha-2 glycoprotein (LRG) in determining small bowel lesions of CD. Methods: This was a cross-sectional observational study. CRP, FC, and LRG were prospectively measured in patients with quiescent CD who underwent imaging examinations (capsule or balloon-assisted endoscopy, magnetic resonance enterography, or intestinal ultrasound) selected by the physician in clinical practice. Mucosal healing (MH) of the small bowel was defined as a lack of ulcers. Patients with a CD activity index >150 and active colonic lesions were excluded. Results: A total of 65 patients (27, MH; 38, small bowel inflammation) were analysed. The area under the curve (AUC) of CRP, FC, and LRG was 0.74 (95% confidence interval: 0.61–0.87), 0.69 (0.52–0.81), and 0.77 (0.59–0.85), respectively. The AUC of FC and LRG in a subgroup of 61 patients with CRP <3 mg/L (26, MH; 32, small bowel inflammation) was 0.68 (0.50–0.81) and 0.74 (0.54–0.84), respectively. The cut-off of 16 μg/mL of LRG showed the highest positive predictive value of 1.00 with specificity of 1.00, while negative predictive value was highest (0.71) with sensitivity of 0.89 at the cut-off of 9 μg/mL. Conclusion: LRG can accurately detect and/or exclude the small bowel lesions with two cut-off values.

Serum leucine-rich alpha-2 glycoprotein levels in rheumatoid arthritis and spondyloarthritis: A promising biomarker

Background: In the early stages of the disease, some of the signs and symptoms of joint inflammation in rheumatoid arthritis (RA) may resemble that of spondyloarthritis (SpA). An examination that can help distinguish RA and SpA is warranted. One such examination is the measurement of serum leucine-rich alpha-2 glycoprotein (LRG) levels. This study aimed to measure serum LRG levels in RA and SpA patients and determine the role of LRG in the diagnosis of RA and SpA. Methods: This is a cross-sectional study consisting of 26 RA subjects and 26 SpA subjects. The SpA subjects were further grouped into ankylosing spondylitis (AS), psoriatic arthritis (PsA), and peripheral SpA. Measurement of serum LRG levels were conducted using ELISA. Difference between LRG levels of the two groups were compared using the Mann-Whitney test. Results: LRG levels were elevated in 76.9% and 84.6% of subjects with RA and SpA, respectively. The median LRG levels were higher in RA subjects (77.03 (27.16–107.73)) than SpA (68.67 (33.15–115.18)). There was no significant difference in LRG levels in RA and SpA subjects (p = .442). The RA and PsA group were predominated by diseases of moderate activity, 88.5% and 58.3%, respectively. In comparison, AS was dominated by high disease activity (85.7%). The highest median LRG levels in AR and SpA subjects were in new-onset patients (82.21 vs. 72.25 µg/dL). Conclusions: There was no significant difference in LRG levels between RA and SpA subjects. The role of LRG in the diagnosis of RA and SpA remains to be determined in future studies.

Serum leucine-rich alpha-2 glycoprotein as a predictive factor of endoscopic remission in Crohn's disease.

The usefulness of fecal calprotectin (FC) and serum leucine-rich alpha-2 glycoprotein (LRG) assessing the activity of Crohn's disease (CD) remains to be fully demonstrated in Asia. The present study aimed to elucidate whether FC and LRG could predict endoscopic remission (ER) in Japanese patients with CD. Between October 2018 and July 2021, we prospectively observed treatment courses of CD patients treated with biologic agents. The optimal cutoff values of Crohn's Disease Activity Index (CDAI), serum C-reactive protein (CRP), serum albumin (Alb), FC, and LRG levels for predicting ER at week 52 were calculated using receiver operating characteristic (ROC) curves. We also analyzed the correlations between the achievement of clinical remission (CR) or biomarker remission (BR) at week 12/24/52 and ER at week 52. Among 53 patients who completed 52weeks of observation, 20 (37.7%) achieved ER at week 52. Using the calculated cutoff values, patients who achieved CR (CDAI≤112) or BR (CRP≤0.42mg/dL, Alb≥3.8g/dL, FC≤287μg/g, or LRG≤13.6μg/mL) at week 12/24/52 had a higher ER rate at week 52. FC-BR at week 12/24 showed low sensitivity (0.58/0.60)but high specificity (0.78/0.74)for predicting ER; LRG-BR at week 12/24 also showed low sensitivity (0.68/0.74) but high specificity (0.87/0.78). However, FC-BR and LRG-BR at week 52 had improved sensitivity (0.80/0.84) while specificity remained (0.79/0.85). From the early phase of biologic treatment, both FC and LRG had high specificity for predicting ER at week 52. LRG showed higher sensitivity than FC.

Serum Leucine-Rich Alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Ulceration detected by Capsule Endoscopy.

Background: Small bowel (SB) lesions in quiescent Crohn’s disease (CD) are sometimes not identified by clinical activity or existing markers. We investigated the usefulness of a novel biomarker, leucine-rich α2-glycoprotein (LRG), for screening for the presence of SB ulcerative lesions detected by small-bowel capsule endoscopy (SBCE). Methods: We examined patients with a Crohn’s Disease Activity Index (CDAI) value < 150 and a C-reactive protein (CRP) value < 0.5 mg/dL with SB or SB colonic CD. The presence of small-bowel ulcerative lesions (≥0.5 cm) was grouped by SBCE results, and we then compared the groups’ LRG value to establish a cutoff value for screening for the presence of lesions. Results: In 40 patients with CD, the LRG values differed significantly between the patients with and without SB ulcerative lesions (Ul + 14.1 (2.1–16.5) μg/mL vs. Ul − 12.3 (9.3–13.5) μg/mL; p = 0.0105). The respective cutoff LRG values for the presence of SB ulcerative lesions was 14 μg/mL (areas under the ROC curve 0.77), with sensitivity 63.6%, specificity 82.8%, positive predictive values 58.3%, negative predictive values 85.7%, and accuracy 78%. Conclusion: These results indicate that LRG may be useful in predicting the presence of SB inflammation associated in patients with CD with CRP < 0.5 mg/dL and CDAI < 150, and in selecting patients for SBCE.

Serum Leucine-Rich Alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Ulceration detected by Capsule Endoscopy

Serum Leucine-Rich Alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Ulceration detected by Capsule Endoscopy

Serum Leucine-Rich Alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Capsule Endoscopy

Serum Leucine-Rich Alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Capsule Endoscopy

Accuracy of Serum Leucine-Rich Alpha-2 Glycoprotein in Evaluating Endoscopic Disease Activity in Crohn's Disease.

Mucosal healing, confirmed by endoscopic evaluation, is the long-term goal of treatment for Crohn's disease (CD). Leucine-rich alpha-2 glycoprotein (LRG) is a new serum biomarker correlated with disease activity in inflammatory bowel disease. However, studies evaluating its relationship with CD, particularly in the context of small intestinal lesions, are scarce. The aim of this study was to investigate the accuracy of LRG in assessing endoscopic activity, especially remission, in patients with CD. Between July 2020 and March 2021, 72 patients with CD who underwent LRG testing and double-balloon endoscopy at the same time were included. Endoscopic activity was evaluated using the applied Simple Endoscopic Score for Crohn's disease, including small intestine lesions. The relationship of LRG with clinical symptoms and endoscopic activity was assessed, and its predictive accuracy was evaluated. Leucine-rich alpha-2 glycoprotein showed a significant positive correlation with endoscopic activity (r = 0.619, P < .001), even in patients with active lesions in the small intestine (r = 0.626, P < .001). Multivariate logistic regression revealed that LRG was the only factor associated with endoscopic remission. An LRG cutoff value of 8.9 μg/mL had a sensitivity of 93.3%; specificity of 83.3%; positive predictive value of 96.6%; negative predictive value of 71.4%; accuracy of 91.7%; and area under the curve of 0.904 for the prediction of endoscopic remission. Leucine-rich alpha-2 glycoprotein can be used in assessing endoscopic activity and is a reliable marker of endoscopic remission in CD patients. It can be an intermediate target in the treatment of CD.

Serum Leucine-Rich alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Capsule Endoscopy

Serum Leucine-Rich alpha-2 Glycoprotein in Quiescent Crohn's Disease as a Potential Surrogate Marker for Small-Bowel Capsule Endoscopy

Leucine-Rich Alpha-2 Glycoprotein in Monitoring Disease Activity and Intestinal Stenosis in Inflammatory Bowel Disease.

Leucine-rich alpha-2 glycoprotein (LRG) is a novel biomarker for monitoring disease activity in inflammatory bowel disease (IBD). The aim of this study was to evaluate its utility in monitoring disease activity. In this retrospective study based on case records between August 2020 and July 2021 at our two centers, we examined the correlation between serum levels of LRG and C-reactive protein (CRP) with disease activity in IBD patients. Background factors related to serum LRG levels were also analyzed. Overall, 47 Crohn's disease (CD) and 123 ulcerative colitis (UC) patients were evaluated. In patients with CD, LRG and CRP levels correlated with Harvey-Bradshaw Index (HBI) and Simple Endoscopic Score for CD (SES-CD) (LRG and HBI, r = 0.397; LRG and SES-CD, r = 0.637; CRP and HBI, r = 0.253; CRP and SES-CD, r = 0.332). In patients with UC, LRG and CRP significantly correlated with the partial Mayo score (PMS) and Mayo endoscopic subscore (MES) (LRG and PMS, r = 0.3; CRP and PMS, r = 0.282; LRG and MES, r = 0.424; CRP and MES, r = 0.459). In CD patients with normal CRP, serum LRG level was significantly higher in those with mucosal inflammation than in those with mucosal healing (16.4 vs. 10.7 μg/ mL). Stenosis was associated with serum LRG levels in CD group using multiple regression analysis. Therefore, LRG is a useful biomarker for monitoring disease activity and mucosal inflammation, and indicates the status of intestinal stenosis in IBD patients.

Leucine-Rich Alpha-2 Glycoprotein May Be Predictive of the Adalimumab Trough Level and Antidrug Antibody Development for Patients with Inflammatory Bowel Disease: A Sub-Analysis of the PLANET Study

Introduction: The aim of this study was to examine whether biomarkers are predictive of the adalimumab (ADA) trough level and antidrug antibody development in patients with Crohn’s disease (CD) and ulcerative colitis (UC). Methods: Using data obtained in a prospective, multicenter, observational study (PLANET), we assessed serial changes in a novel biomarker – leucine-rich alpha-2 glycoprotein (LRG) – during ADA treatment for patients with active CD and UC. We measured serum LRG, C-reactive protein (CRP), and fecal calprotectin (fCAL) at weeks 0, 12, 24, and 52. The ADA trough level and anti-ADA antibody (AAA) were also measured at weeks 12 and 52. Correlations between the ADA trough level, AAA, and biomarkers were examined. Results: In all, 34 patients with CD and 47 patients with UC were enrolled. The ADA trough level at week 12 or at the time of ADA withdrawal was 8.5 ± 3.9 in the AAA-negative group (n = 70) and 2.9 ± 2.7 μg/mL in the AAA-positive group (n = 8) (p < 0.0001). The ADA trough level at week 12 or at the time of ADA withdrawal was associated with pretreatment LRG (p = 0.0437 and r = −0.23). Conclusion: LRG, rather than CRP or fCAL, may be a marker for predicting the trough level of ADA for patients with CD and UC treated with ADA.