Diagnostic and clinical role of serum proteinase 3 antineutrophil cytoplasmic antibodies in inflammatory bowel disease

A Case of Acute Aortic Occlusion Occurring in Association with COVID-19 Infection and Ulcerative Colitis

A 53-year-old woman visited her district hospital complaining of right lower limb numbness 8 days after being diagnosed with COVID-19. She had been suffering diarrhea for 25 days before the hospital visit. Computed tomography showed multiple arterial and venous thromboses, and anticoagulation with a therapeutic dose of heparin was initiated. Acute aortic occlusion occurred on hospital day 5, and balloon thromboembolectomy was performed for revascularization of the lower limbs 9 hours after onset. Ulcerative colitis was diagnosed on postoperative day 7. With the anticoagulation and immunosuppression therapy, no thromboembolic event occurred postoperatively.

Refractory Ulcerative Colitis With Associated Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis Syndrome Successfully Treated With Tofacitinib

Synovitis, acne, pustulosis, hyperostosis, osteitis (SAPHO) syndrome is a rare inflammatory condition associated with inflammatory bowel disease. Limited data exist on standardized management. We report a case of refractory SAPHO syndrome and ulcerative colitis (UC) treated successfully with tofacitinib. A 54-year-old man with UC presented with an intractable headache. A diagnosis of SAPHO syndrome was made based on the finding of sterile osteitis in the skull base and persistent severe UC. Symptoms, imaging, and endoscopy revealed persistent UC and osteitis despite multiple therapies. Tofacitinib was initiated and clinical remission was achieved. Tofacitinib is an effective treatment of refractory inflammatory bowel disease and SAPHO syndrome.

Clinical Validity of Anti-Proteinase 3 Antibodies in Patients with Inflammatory Bowel Disease: A Short Meta-Analysis

Anti-neutrophil cytoplasmic antibodies (ANCA) directed to proteinase 3 (PR3) represent highly established markers for patients with ANCA-associated vasculitis (AAV). PR3-ANCA have also demonstrated utility in the management of inflammatory bowel disease (IBD). More specifically, PR3-ANCA discriminate individuals with ulcerative colitis (UC) from Crohn's disease (CD) patients and are associated with disease severity, activity, and treatment non-response. Here, we aim to summarize the current data on the diagnostic utility of PR3-ANCA in IBD. A structured, systematic literature review, including three electronic databases, was conducted on June 6th, 2023, to identify studies assessing the diagnostic accuracy of the QUANTA Flash® PR3 assay in UC vs. CD patients. Electronic searches were supplemented by hand searching. A hierarchical, bivariate, mixed-effect meta-analysis was conducted using the metandi function, as per the Cochrane collaboration recommendations. Study quality was assessed using the QUADAS-2 tool, which considers the risk of bias and applicability. Six out of a hundred and eleven citations met the inclusion criteria and reported QUANTA Flash® PR3 diagnostic accuracy in UC vs. CD (UC, n = 667, CD, n = 682 patients). The sensitivity/specificity point estimate for UC was 34.9%/95.9%. This resulted in a Diagnostic Odds Ratio (DOR) of 12.6. The risk of bias was low in the index test and reference standard domains. Four of the six studies (67%) showed an unclear risk of bias in patient selection and in flow and timing domains. All studies had low concerns about applicability in all the domains. PR3-ANCA measured with the QUANTA Flash® PR3 assay represent novel diagnostic markers in IBD and enables discrimination between UC and CD.

Development of a scoring system for predicting the severity of ulcerative colitis

BACKGROUND AND STUDY AIMS

Monitoring disease activity in ulcerative colitis (UC) is critical in preventing long-term complications. This study aims to develop a scoring system using non-invasive indicators to predict endoscopic activities for ulcerative colitis (UC) patients.

PATIENTS AND METHODS

All enrolled patients with UC admitted to Shanghai Xinhua Hospital between June 2017 and January 2021 were enrolled, and their clinical data were retrospectively collected and a number of serological biomarkers concentrations were analyzed. Patients were categorized into mild and moderate-to-severe disease groups. Univariate and multivariate logistic regression was used to predict moderate-to-severe endoscopic activities, which were then incorporated into a nomogram to establish a prediction scoring model.

RESULT

Overall, 231 patients were divided into a mild group (n = 111, 48.0%) and a moderate-to-severe group (n = 120, 52.0%). The following variables were independently associated with the disease severity and were subsequently included into the prediction model: Proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA), C-reactive protein (CRP), hemoglobin(Hb), IL-10, stool frequency ≥ 5 times/day and hematochezia. Incorporating these 6 factors, the nomogram showed good discrimination with C-index of 0.819 and reliable calibration. A scoring model was established with the area under the curve 0.818. Moreover, PR3-ANCA and CRP correlated with the duration of hospital stay.

CONCLUSION

We developed a predictive model for endoscopic disease activities by using noninvasive factors based on PR3-ANCA, CRP, Hb, IL-10, stool frequency and hematochezia. This prediction model might assist clinicians in managing patients with UC.

Systemic immune-inflammation index as a potential biomarker to monitor ulcerative colitis

OBJECTIVE

The treat-to-target strategy is recommended by Selecting Therapeutic Targets in Inflammatory Bowel Disease II (STRIDE-II) for treating ulcerative colitis (UC), and monitoring remission status is crucial during this management. The systemic immune-inflammation index (SII), defined as platelet * neutrophil/lymphocyte, is a complete blood count-based index reflecting the balance of immune and inflammatory status. This study aims to investigate the feasibility of SII for diagnosing UC and monitoring UC disease activity.

METHODS

This study retrospectively analyzed patients with UC and controls. Relationships between SII and Mayo clinical score, Mayo Endoscopic Score (MES), and Nancy Histological Index (NHI) were evaluated.

RESULTS

167 patients with UC and 106 controls were included. SII significantly increased in patients with UC and was closely correlated with the Mayo clinical score, MES, and NHI. SII diagnosed UC with a cut-off value of 619.1 × 109/L (area under the curve = 0.861, p < 0.0001, sensitivity 79.64%, specificity 77.36%), evaluated clinical remission status with a cut-off value of 1068 × 109/L (area under the curve = 0.691, p < 0.05, sensitivity 55.71%, specificity 81.48%), endoscopic improvement with a cut-off value of 981.3 × 109/L (area under the curve = 0.819, p < 0.0001, sensitivity 65.22%, specificity 89.66%), and histological healing with a cut-off value of 689.3 × 109/L (area under the curve = 0.898, p < 0.0001, sensitivity 88.89%, specificity 95.83%).

CONCLUSION

SII is a potential biomarker for diagnosing UC and monitoring UC disease severity, especially in evaluating mucosal and histological healing during the long-term management in treat-to-target strategy. However, further research is needed to confirm its usefulness and optimize its clinical application.

Biomarkers in IBD: What to Utilize for the Diagnosis?

The role of biomarkers in the diagnosis of inflammatory bowel disease is not fully characterized. C-reactive protein has a short half-life and elevates quickly after the onset of an inflammatory process; the performance is better in Crohn's disease than in ulcerative colitis. Erythrocyte sedimentation rate is easy to determine, widely available, and cheap, but the long half-life, the influence of age, anemia, smoking, and drugs limit its usefulness. Fecal markers have good specificity, but suboptimal accuracy. Microbial antibodies and novel immunological markers show promise but need further evidence before entering clinical practice. Proteomic methods could represent the dawn of a new era of stool protein/peptide biomarker panels able to select patients at risk of inflammatory bowel disease.

Serum ANCA as Disease Biomarkers: Clinical Implications Beyond Vasculitis

Usually associated with autoimmune diseases, anti-neutrophil cytoplasmic antibodies are also detected in other conditions, such as infections, malignancies, and after intake of certain drugs. Even if the mechanisms of production and their pathogenic role have not been fully elucidated yet, ANCA are widely recognized as a clinically alarming finding due to their association with various disorders. While ANCA target several autoantigens, proteinase-3, and myeloperoxidase are the ones proved to be most frequently related to chronic inflammation and tissue damage in murine models. Albeit these autoantibodies could be present as an isolated observation without any implications, ANCA are frequently used in clinical practice to guide the diagnosis in a suspect of small vessel vasculitis. Conditions that should prompt the clinician to test ANCA status range from various forms of lung disease to renal or peripheral nervous system impairment. ANCA positivity in the presence of an autoimmune disease, especially rheumatoid arthritis, or connective tissue diseases, is frequently correlated with more clinical complications and treatment inefficacy, even in the absence of signs of vasculitis. For this reason, it has been postulated that ANCA could represent the final expression of an immune dysregulation rather than a pathogenic event responsible for organs damage. Recently, it has also been proposed that ANCA specificity (PR3 or MPO) could possibly define ANCA-associated vasculitides better than clinical phenotype. This review aims at summarizing the latest advancements in the field of ANCA study and clinical interpretation.

Anti-Proteinase 3 Antibodies as a Biomarker for Ulcerative Colitis and Primary Sclerosing Cholangitis in Children

OBJECTIVES

Anti-neutrophil cytoplasmic antibody (ANCA) directed against proteinase 3 (PR3) is a marker for granulomatosis with polyangiitis, but is also found in patients with inflammatory bowel disease (IBD), mainly ulcerative colitis (UC). The aim of our study was to investigate ANCA and PR3-ANCA in paediatric IBD.

METHODS

We tested 326 paediatric IBD patients and 164 controls for anti-Saccharomyces cerevisiae antibodies (ASCA), ANCA (indirect immunofluorescence, IIF) and PR3-ANCA (chemiluminescence immunoassay). We applied the Paris classification for paediatric IBD and documented liver manifestations such as primary sclerosing cholangitis (PSC) and autoimmune hepatitis (AIH).

RESULTS

We found PR3-ANCA in 49/121 (40%) of UC, 20/187 (11%) of Crohn disease (CD) and 2/18 (11%) of IBD-unclassified (IBD-U) patients but in none of the controls. 54% UC and 12% CD patients were positive for ANCA (IIF). PR3-ANCA positive UC patients were characterised by more extensive disease (P = .070). Fourteen of 21 (67%) of UC patients with backwash ileitis were anti-PR3 ANCA-positive (P = .011). We diagnosed PSC or PSC/AIH in 19 UC and 3 IBD-U patients. Fifteen of 22 (68%) patients with PSC or PSC/AIH were anti-PR3-ANCA positive in contrast to 36 of 117 (32%) patients without PSC (P = .001). PR3-ANCA positive patients showed higher levels of gamma-glutamyl transferase, alanine transaminase and aspartate transferase (P < 0.001, 0.001, 0.006, respectively). Forty-seven percent of CD and 6% of UC patients were ASCA-IgA positive. PR3-ANCA-positive and -negative patients showed no significant differences concerning age at diagnosis, disease activity, need for drugs, and number of hospitalisations.

CONCLUSIONS

Our study provides data for PR3-ANCA as a potential serological marker for paediatric UC and PSC.

Role of Serum Proteinase 3 Antineutrophil Cytoplasmic Antibodies in the Diagnosis, Evaluation of Disease Severity, and Clinical Course of Ulcerative Colitis

Background/Aims

Proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA) is a serologic marker for granulomatosis with polyangiitis. However, recent studies have also shown their role as diagnostic markers for ulcerative colitis (UC). This study was performed to investigate the clinical roles of PR3-ANCAs in the disease severity, disease extension, and clinical course of UC.

Methods

Serum PR3-ANCAs were measured in 173 UC patients including 77 patients with new-onset patients UC diagnosed within 1 month, 110 patients with Crohn’s disease, 48 patients with other intestinal diseases, and 71 healthy controls. Associations between the PR3-ANCA titer and clinical data, such as disease severity, disease extension, and clinical course, were assessed. The clinical utility of PR3-ANCA measurement was evaluated by receiver operating characteristic (ROC) analysis.

Results

PR3-ANCA ≥3.5 U/mL demonstrated 44.5% sensitivity and 95.6% specificity for the diagnosis of UC in all patients. PR3-ANCA positivity was more prevalent in the 77 new-onset UC patients (58.4%). In this group, the disease severity and extension were more severe in PR3-ANCA positive patients than in PR3-ANCA negative group (p<0.001). After treatment, the partial Mayo scores were significantly decreased with the PR3-ANCA titers. The proportion of patients who required steroids for induction therapy was significantly higher among PR3-ANCA positive than negative group. ROC analysis revealed that PR3-ANCA ≥3.5 U/mL had 75% sensitivity and 69.0% specificity for steroid requirement in new-onset UC patients.

Conclusions

Our results indicate that PR3-ANCA measurement is useful not only for diagnosing UC but also for evaluating disease severity and extension and predicting the clinical course.

Case Report: Proteinase 3 Antineutrophil Cytoplasmic Antibody-Associated Ulcerative Colitis Presenting as Recurrent Intestinal Pseudo-Obstruction in a Teenage Patient With in situ Proteinase 3 Immunohistochemical Staining

Ulcerative colitis (UC) is a chronic relapsing inflammatory bowel disease with the colorectum as its major target organ. Involvement of the upper gastrointestinal tract in UC is rare and presents with nonspecific endoscopic and microscopic characteristics. Recent studies have demonstrated proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA) to be a serological marker for differentiating UC from Crohn's disease in children and for detecting disease activity and nonresponse to steroid therapy and antitumor necrotizing factor-α agents. Herein, we report a 13-year-old female patient mainly presenting with recurrent bilious vomiting who was initially diagnosed with acute gastroenteritis. Intestinal pseudo-obstruction was confirmed through observation of a patent but segmentally dilated jejunum in the barium follow-through examination and other imaging; such obstruction can be attributed to backwash ileitis, superior mesenteric artery syndrome, ileus due to hypokalemia, or PR3-associated enteritis. Laboratory data revealed leukocytosis with neutrophil predominance and serum antinuclear antibody and PR3-ANCA positivity. Overlapping syndrome with autoimmune diseases was suspected. Pathology revealed a crypt abscess with aggregates of neutrophils consistent with UC but did not indicate vasculitis. The in situ immunohistochemical staining revealed PR3 density mainly in the colon and focally in the duodenum. To our knowledge, this is the first case report with in situ pathological evidence of PR3 in inflamed intestinal tissues in a patient with UC and with rare initial presentation of intestinal pseudo-obstruction-induced recurrent bilious vomiting. Whether the clinical features of the present case constitute overlap syndrome with other autoimmune disease or a disease variation of UC warrants further investigation. Notably, the patient's serum PR3-ANCA titers remained high in coincidence with increased disease activity and nonresponse to steroid therapy, but became lower after infliximab treatment. PR3-ANCA as a potential serum biomarker to aid in making differential diagnoses of UC in children, correlating disease activity, and predicting therapeutic responses was also reviewed.

Anti-proteinase 3 antineutrophil cytoplasmic antibody reflects disease activity and predicts the response to steroid therapy in ulcerative colitis

Background

Serum anti-proteinase 3 antineutrophil cytoplasmic antibody (PR3-ANCA) is a disease-specific antibody against granulomatosis with polyangiitis. PR3-ANCA is a useful serological marker for disease severity in ulcerative colitis (UC). The purpose of this study was to investigate whether PR3-ANCA levels could also predict the success of induction therapy and to compare its performance against other markers, including serum CRP and fecal hemoglobin.

Methods

This was a multicenter retrospective study. In total, 159 patients with active-phase UC underwent colonoscopy. Disease activity was measured using the Mayo endoscopic subscore (MES). PR3-ANCA positivity and the response to induction therapy, either 5-aminosalicylic acid or steroid, were assessed. PR3-ANCA, CRP, and fecal hemoglobin were measured during the active phase, and during clinical remission.

Results

Eighty-five (53.5%) of 159 patients with active UC were positive for PR3-ANCA. PR3-ANCA titers were significantly higher in the group of patients with MES 3 compared to patients with MES 1 (P = 0.002) or MES 2 (P = 0.035). Steroid therapy was administered to 56 patients with a median partial Mayo score of 7 (5–9), which is equivalent to moderate-to-severe disease activity. PR3-ANCA positivity of non-responders to steroid therapy was significantly higher than that of responders (71.9% vs, 41.7%, P = 0.030), whereas CRP and fecal hemoglobin were not predictive of steroid response. Multivariate analysis demonstrated that PR3-ANCA positivity was associated with non-response to steroid therapy (odds ratio 5.19; 95% confidence interval, 1.54–17.5; P = 0.008). Of the 37 patients treated to clinical remission who were also positive for PR3-ANCA during the active phase, 27 had an MES of ≥ 1, and 10 patients had an MES of 0. In clinical remission, the proportion of patients with MES 0 in 17 patients whose PR3-ANCA became negative was significantly higher than that in 20 patients whose PR3-ANCA remained positive (47.1% vs. 10.0%, P = 0.023).

Conclusions

PR3-ANCA not only serves as a marker of disease activity, but also predicts the failure of steroid therapy in moderate-to-severe UC.

Trial registration: This study was retrospectively registered in the UMIN Clinical Trials Registry System (000039174) on January 16, 2020.

Serum PR3-ANCA Is a Predictor of Primary Nonresponse to Anti-TNF-α Agents in Patients with Ulcerative Colitis

Background

Anti-tumor necrosis factor-α (TNF-α) agents are effective for moderately to severely active ulcerative colitis (UC). Nonetheless, a proportion of patients fail to respond to these agents as therapy for induction of remission. Recent studies indicated that perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) may predict response to anti-TNF-α agents in UC patients. However, whether PR3-ANCA can predict primary nonresponse (PNR) to anti-TNF-α agents has not yet been evaluated. The aim of this study was to examine whether PR3-ANCA can predict PNR to anti-TNF-α in UC patients.

Methods

This was a single-center retrospective study. Data were extracted from 50 patients with UC who had measurements of PR3-ANCA and received anti-TNF-α agents for the first time as induction therapy. The primary endpoint of this study was a proportion of patients with PNR stratified by PR3-ANCA positivity. PNR to anti-TNF-α agents was defined as failure to achieve reduction in partial Mayo score by 2 or more points and change to other therapeutics within 6 weeks.

Results

Fourteen (28%) of the 50 patients were PR3-ANCA positive. Seventeen (34%) of the 50 patients demonstrated PNR. Eleven (78.6%) of the 14 PR3-ANCA-positive patients demonstrated PNR, while 6 (16.7%) of the 36 PR3-ANCA-negative patients demonstrated PNR. Multivariate analysis demonstrated that PR3-ANCA positivity was associated with PNR to anti-TNF-α agents (odds ratio 19.29, 95% CI: 3.30-172.67; p = 0.002).

Conclusion

PR3-ANCA positivity can predict PNR to anti-TNF-α agents in UC patients.

Diagnostic accuracy of serum proteinase 3 antineutrophil cytoplasmic antibodies in children with ulcerative colitis

BACKGROUND AND AIM

Serologic markers such as myeloperoxidase (MPO) antineutrophil cytoplasmic antibodies (ANCA) (MPO-ANCA) have been used to screen patients for ulcerative colitis (UC). However, MPO-ANCA shows limited accuracy in Asians. Proteinase 3 ANCA (PR3-ANCA) has performed better at UC diagnosis in Japanese adults than MPO-ANCA. The present study aimed to evaluate usefulness of PR3-ANCA for diagnosis of UC in Japanese pediatric practice.

METHODS

Patients under 17 years old undergoing assessment at 12 Japanese pediatric centers between November 2016 and February 2018 were prospectively enrolled and divided into groups with UC, Crohn's disease (CD), intestinal disease control (IC), and healthy control (HC). Serum PR3-ANCA and MPO-ANCA were analyzed using chemiluminescence enzyme immunoassay kits.

RESULTS

Sera from 367 patients (148 with UC at a median age of 12 years; 120 with CD, 13 years; 56 with IC, 10.5 years; and 43 with HC, 10 years) were examined. Median PR3-ANCA values in UC (1.6 U/mL) were greater than in CD (0.2; P < 0.001), IC (0.15; P < 0.001), and HC (0.1; P < 0.001). In receiver operating characteristic curve analyses, the area under the curve for PR3-ANCA was 0.79, significantly greater than for MPO-ANCA (0.58; P < 0.001). Using a cut-off value of 0.8 U/mL determined from the receiver operating characteristic analyses, PR3-ANCA showed significantly greater sensitivity (64.9%) than MPO-ANCA (cut-off, 0.2 U/mL; sensitivity, 19.6%; P < 0.001) and good specificity (83.6%).

CONCLUSIONS

In Japanese children and adolescents, PR3-ANCA performed better as a serologic marker for diagnosis of UC than MPO-ANCA. To our knowledge, this is the first report of such a comparison.

A Review of Selected IBD Biomarkers: From Animal Models to Bedside

Inflammatory bowel disease (IBD) is a dysregulated inflammatory condition induced by multiple factors. The etiology of IBD is largely unknown, and the disease progression and prognosis are variable and unpredictable with uncontrolled disease behavior. Monitoring the status of chronic colitis closely is challenging for physicians, because the assessment of disease activity and severity require invasive methods. Using laboratory biomarkers may provide a useful alternative to invasive methods in the diagnosis and management of IBD. Furthermore, patients with ulcerative colitis or Crohn’s disease are also at risk of developing cancer. Annual colonoscopies can help lower the risk for developing colorectal cancer. However, laboratory biomarkers may also be helpful as non-invasive indicators in predicting treatment responses, improving prognosis, and predicting possible tumors. This review addresses selected laboratory biomarkers (including ANCA, chitinase 3-like 1, S100A12/RAGE, calprotectin, and TNF/TNFR2), which are identified by utilizing two well-accepted animal models of colitis, dextran sodium sulfate-induced and T cell receptor alpha knockout colitis models. In addition to being useful for monitoring disease severity, these biomarkers are associated with therapeutic strategies. The factors may regulate the initiation and perpetuation of inflammatory factors in the gut.

2020 international consensus on ANCA testing beyond systemic vasculitis

This document follows up on a 2017 revised international consensus on anti-neutrophil cytoplasm antibodies (ANCA) testing in granulomatosis with polyangiitis and microscopic polyangiitis and focuses on the clinical and diagnostic value of ANCA detection in patients with connective tissue diseases, idiopathic interstitial pneumonia, autoimmune liver diseases, inflammatory bowel diseases, anti-glomerular basement membrane (GBM) disease, infections, malignancy, and during drug treatment. Current evidence suggests that in certain settings beyond systemic vasculitis, ANCA may have clinical, pathogenic and/or diagnostic relevance. Antigen-specific ANCA targeting proteinase-3 and myeloperoxidase should be tested by solid phase immunoassays in any patient with clinical features suggesting ANCA-associated vasculitis and in all patients with anti-GBM disease, idiopathic interstitial pneumonia, and infective endocarditis associated with nephritis, whereas in patients with other aforementioned disorders routine ANCA testing is not recommended. Among patients with autoimmune liver diseases or inflammatory bowel diseases, ANCA testing may be justified in patients with suspected autoimmune hepatitis type 1 who do not have conventional autoantibodies or in case of diagnostic uncertainty to discriminate ulcerative colitis from Crohn's disease. In these cases, ANCA should be tested by indirect immunofluorescence as the target antigens are not yet well characterized. Many questions concerning the optimal use of ANCA testing in patients without ANCA-associated vasculitis remain to be answered.

The diagnostic role and clinical association of serum proteinase 3 anti-neutrophil cytoplasmic antibodies in Chinese patients with inflammatory bowel disease

Background and aim: Accurate differentiation of patients with ulcerative colitis (UC) or Crohn's disease (CD) is important for appropriate therapy and prognosis. This study was designed to explore the utility of proteinase 3 anti-neutrophil cytoplasmic antibodies (PR3-ANCA) in the diagnosis of Chinese patients with inflammatory bowel disease (IBD).Methods: Blood samples were collected from 216 Chinese patients, including 175 IBD and 41 colorectal polyps (disease control). Clinical characteristics were extracted from electronic medical records.Results: Serum PR3-ANCA were increased in UC patients compared to those with CD or colorectal polyps (p < .0001). PR3-ANCA was negative in colorectal polyps and there was no significant difference between CD and colorectal polyps (p > .05). Using the cut-off value of 20 chemiluminescent units (CU) provided by manufacturer, the positive rate of PR3-ANCA was higher in UC than CD (41.7% vs. 1.1%; p < .0001). Receiver operating characteristic (ROC) analysis demonstrated an area under the curve (AUC) of 0.89 (95% CI: 0.84-0.95; p < .0001) for differentiating UC from CD and suggested an optimized cutoff of 7.3 CU which improved sensitivity from 41.7% to 57.1%, while maintaining a specificity of 98.9%. PR3-ANCA in severe UC patients were higher than those with moderate UC (p < .05), no difference was found between those in remission or with mild or moderate activity (p > .05).Conclusions: Serum PR3-ANCA is a potentially useful clinical biomarker in Chinese patients with IBD. A modified cut-off value of 7.3 CU improves the performance for distinguishing UC from CD.

Antibodies to Crohn's disease peptide 353 as a diagnostic marker for pediatric Crohn's disease: a prospective multicenter study in Japan

BACKGROUND

Various serologic markers such as anti-glycoprotein 2 antibodies and anti-Saccharomyces cerevisiae antibodies have been reported to be diagnostically useful in Crohn's disease. Mitsuyama et al. reported that antibodies to Crohn's disease peptide 353, a newly proposed serologic marker, were more useful in Japanese adults than anti-Saccharomyces. We addressed the same issue in Japanese children and adolescents.

METHODS

Prospectively enrolled subjects under 17 years old assessed and treated at 12 pediatric centers in Japan included groups with Crohn's disease, ulcerative colitis, other intestinal diseases, or good health. The 3 serum markers were analyzed by enzyme-linked immunosorbent assays.

RESULTS

Enrolled subjects, numbering 367, included 120 with Crohn's disease, 148 with ulcerative colitis, 56 with other intestinal diseases, and 43 healthy subjects. In Crohn's disease, anti-Crohn's disease peptide 353, anti-glycoprotein 2, and anti-Saccharomyces concentrations (median, 2.25, 3.0, and 8.9 U/mL) were significantly greater than in ulcerative colitis (1.1, 1.9, and 3.4; all P < 0.001), other intestinal diseases (1.1, 1.85, and 2.95; all P < 0.001), and healthy controls (1.1, 1.7, and 2.8; all P < 0.001), respectively. At 95% specificity, sensitivity of anti-Crohn's disease peptide (45.0%) was significantly higher than for anti-glycoprotein 2 (30.8%; P < 0.05) or anti-Saccharomyces (26.7%; P < 0.01).

CONCLUSIONS

Anti-Crohn's disease peptide 353 proved more useful for diagnosis of Crohn's disease in Japanese children than the other 2 markers. To our knowledge, this is the first pediatric report to that effect.

Epidemiology and Clinical Outcomes of Inflammatory Bowel Disease: A Hospital-Based Study in Central Taiwan

The incidence and prevalence of inflammatory bowel disease (IBD) are low but increasing in Taiwan. We aimed to investigate the epidemiology and clinical outcomes of IBD in central Taiwan. We retrospectively analyzed patients with IBD diagnosed at our hospital between January 2000 and September 2018. The diagnostic criteria were based on endoscopic and pathologic findings. Clinical characteristics, treatment regimens, and treatment outcomes were analyzed. A total of 190 patients with IBD were enrolled (80 with Crohn's disease (CD) and 110 with ulcerative colitis (UC)). The mean age at diagnosis was 38.4 years (CD: 36 years, UC: 40 years). Male patients accounted for the majority of patients (71.1%). The male-to-female ratio was 3 : 1 for CD and 2.1 : 1 for UC. Current and ever smokers accounted for 30.5% of all patients. Only 4.2% of patients had a family history of IBD. Extraintestinal manifestations (EIMs) were reported in 7.9%, and colorectal cancers (CRCs) were reported in 2.1% of all patients. In patients with CD, the ileal type was the most common disease phenotype (57.5%), and the stricturing type was the most common disease behavior (60.0%). In patients with UC, left-sided colitis was the predominant disease extent (42.7%). The seroprevalence of hepatitis B virus (HBV) was 13.3%. The incidence of perinuclear anti-neutrophil cytoplasmic antibody (p-ANCA) in patients with UC was 22%. 5-Aminosalicylic acids were the preferred treatment for UC, whereas corticosteroids, immunomodulators, and biologic agents were preferred for CD. In patients with CD, the bowel resection rate was 38.8%, and the incidence of hip avascular necrosis was 3.8%. In Taiwan, patients with IBD showed a male predominance, lack of familial clustering, a higher prevalence of HBV infection, and a lower prevalence of p-ANCA, EIMs, and CRC. Moreover, a higher incidence of the ileal type with poor outcomes of CD and left-sided predominance in UC were found.

A Simple Fecal Bacterial Marker Panel for the Diagnosis of Crohn's Disease

Background and Aims: Intestinal dysbiosis is implicated in the pathogenesis of Crohn’s disease (CD). We evaluated fecal and sera microbial markers for clinical use in detecting CD.

Methods: Fecal samples from 346 Asian subjects were collected, including 95 patients with CD, 81 patients with ulcerative colitis (UC), 65 patients with irritable bowel syndrome (IBS), and 105 healthy subjects (HS). Microbial indicators Fusobacterium nucleatum (Fn), Faecalibacterium prausnitzii (Fp), and Escherichia coli (E. coli) were identified based on a review of the literature. The relative abundance of the three bacterial markers were measured by qPCR, and two serological microbial markers (anti-Fn, anti-E. coli) were measured by ELISA. We evaluated the diagnostic performance of these microbial markers by ROC curve analysis.

Results: The quantification of Fp, Fn, and E. coli of fecal samples is relatively stable when stored up to 6 h at room temperature. The significant increasing abundances of Fn were accompanied by a decline of Fp in the CD group. Fn exhibited a slightly higher diagnostic value than Fp in distinguishing CD from HS (Area Under Curve, AUC = 0.841 vs. 0.811) or irritable bowel syndrome (IBS) groups (AUC = 0.767 vs. 0.658), and the further combination of Fn and Fp improved the diagnostic value (HS, AUC = 0.867; IBS, AUC = 0.771). However, anti-E. coli and anti-Fn antibodies in serum did not possess diagnostic value for CD or UC.

Conclusion: A combination of fecal Fn and Fp was identified as a valuable marker for CD diagnosis. A CD bacterial marker panel may provide a simple non-invasive approach to screen for CD.

PR3-ANCA and panel diagnostics in pediatric inflammatory bowel disease to distinguish ulcerative colitis from Crohn's disease

Background

Accurate classification of patients with inflammatory bowel disease into the subtypes ulcerative colitis (UC) and Crohn’s disease (CD) is still a challenge, but important for therapy and prognosis.

Objectives

To evaluate the diagnostic utility of anti-neutrophil cytoplasmic antibodies specific for proteinase-3 (PR3-ANCA) for ulcerative colitis (UC) and the value of an antibody panel incorporating PR3-ANCA to differentiate between Crohn’s disease (CD) and UC.

Study design

In this cohort study, 122 pediatric and adolescent individuals were retrospectively included (61 IBD patients of two clinical centers, 61 non-IBD controls). All subjects had a comprehensive antibody profile done from stored sera taken close to time of diagnosis. By employing quasi-exhaustive logistic regression the best discriminative model for UC and CD,subjects was determined in a training cohort and confirmed in a validation cohort.

Results

PR3-ANCA was specifically associated with UC (odds ratio (OR), 17.6; 95% confidence interval (CI); 3.6, 87); P < .001). A four antibody-panel including PR3-ANCA had an AUC of 90.81% (95%CI; 81.93, 99.69) to distinguish between UC and CD in the training cohort. In a smaller external validation cohort, the AUC was 84.13% (95%CI; 64.21, 100) for accurate diagnosis of CD and UC.

Conclusion

PR3-ANCA is highly specific for UC. The differentiating capability of a panel, which contains PR3-ANCA and weighs broadly available antibodies, is superior and utilization of the panel can support accurate classification in the work-up of pediatric and adolescent patients with IBD patients.

Antineutrophil cytoplasmic antibody-positive familial Mediterranean fever and hyperthyroidism: A case report

RATIONALE

Familial Mediterranean fever (FMF) is a genetic autoinflammatory disorder characterized by serositis and recurrent fever. Previous reports identified patients with antineutrophil cytoplasmic antibody (ANCA)-positive FMF, but vasculitis symptoms were not reported.

PATIENT CONCERNS

We report the case of a 44-year-old man with numbness. He had a history of 3 episodes of pleurisy and was being treated with propylthiouracil for hyperthyroidism. Because he was ANCA-positive, we suspected drug-induced ANCA-associated vasculitis and propylthiouracil was discontinued. However, his numbness was not ameliorated, and he again developed high fever with pleurisy.

DIAGNOSIS

Diagnosis of FMF was finally made, and genetic analysis revealed compound heterozygous mutations in exon 2 of the familial Mediterranean fever gene (L110P/E148Q).

INTERVENTIONS

The patient was treated with 0.5 mg/day of colchicine.

OUTCOMES

His numbness improved, and fever has not recurred.

LESSONS

Appearance of ANCA and development of vasculitis should be considered in a clinical course of FMF with hyperthyroidism.