Calprotectin serum levels on admission and during follow-up predict severity and outcome of patients with COVID-19: A prospective study

BACKGROUND & AIMS

Calprotectin reflects neutrophil activation and is increased in various inflammatory conditions including severe COVID-19. However, serial serum calprotectin measurements in COVID-19 patients are limited. We assessed prospectively, calprotectin levels as biomarker of severity/outcome of the disease and a COVID-19 monitoring parameter in a large cohort of consecutive COVID-19 patients.

METHODS

Calprotectin serum levels were measured in 736 patients (58.2 % males; median age 63-years; moderate disease, n = 292; severe, n = 444, intubated and/or died, n = 50). Patients were treated with combined immunotherapies according to our published local algorithm. The endpoint was the composite event of intubation due to severe respiratory failure (SRF)/COVID-19-related mortality.

RESULTS

Median (interquartile range) calprotectin levels were significantly higher in patients with severe disease [7(8.2) vs. 6.1(8.1)μg/mL, p = 0.015]. Calprotectin on admission was the only independent risk factor for intubation/death (HR=1.473, 95 %CI=1.003-2.165, p = 0.048) even after adjustment for age, sex, body mass index, comorbidities, neutrophils, lymphocytes, neutrophil to lymphocytes ratio, ferritin, and CRP. The area under the curve (AUC, 95 %CI) of calprotectin for prediction of intubation/death was 0.619 (0.531-0.708), with an optimal cut-off at 13 μg/mL (sensitivity: 44 %, specificity: 79 %, positive and negative predictive values: 13 % and 95 %, respectively). For intubated/died patients, paired comparisons from baseline to middle of hospitalization and subsequently to intubation/death showed significant increase of calprotectin (p = 0.009 and p < 0.001, respectively). Calprotectin alteration had the higher predictive ability for intubation/death [AUC (95 %CI):0.803 (0.664-0.943), p < 0.001].

CONCLUSIONS

Calprotectin levels on admission and their subsequent dynamic alterations could serve as indicator of COVID-19 severity and predict the occurrence of SRF and mortality.

Calprotectin Impairs Platelet Survival in Patients With Primary Antiphospholipid Syndrome

OBJECTIVE

While thrombosis and pregnancy loss are the best-known clinical features of antiphospholipid syndrome (APS), many patients also exhibit "extra-criteria" manifestations, such as thrombocytopenia. The mechanisms that drive APS thrombocytopenia are not completely understood, and no clinical biomarkers are available for predicting antiphospholipid antibody (aPL)-mediated thrombocytopenia. Calprotectin is a heterodimer of S100A8 and S100A9 that is abundant in the neutrophil cytoplasm and released upon proinflammatory neutrophil activation. Here, we sought to evaluate the presence, clinical associations, and potential mechanistic roles of circulating calprotectin in a cohort of primary APS and aPL-positive patients.

METHODS

Levels of circulating calprotectin were determined in plasma by the QUANTA Flash chemiluminescent assay. A viability dye-based platelet assay was used to assess the potential impact of calprotectin on aPL-mediated thrombocytopenia.

RESULTS

Circulating calprotectin was measured in 112 patients with primary APS and 30 aPL-positive (without APS criteria manifestations or lupus) patients as compared to patients with lupus (without APS), patients with unprovoked venous thrombosis (without aPL), and healthy controls. Levels of calprotectin were higher in patients with primary APS and aPL-positive patients compared to healthy controls. After adjustment for age and sex, calprotectin level correlated positively with absolute neutrophil count (r = 0.41, P < 0.001), positively with C-reactive protein level (r = 0.34, P = 0.002), and negatively with platelet count (r = -0.24, P = 0.004). Mechanistically, we found that calprotectin provoked aPL-mediated thrombocytopenia by engaging platelet surface toll-like receptor 4 and activating the NLRP3-inflammasome, thereby reducing platelet viability in a caspase-1-dependent manner.

CONCLUSION

These data suggest that calprotectin has the potential to be a functional biomarker and a new therapeutic target for APS thrombocytopenia.

Autoimmune gastritis serological biomarkers in gastric cancer patients

The role of autoimmunity in the pathogenesis of gastric cancer remains controversial. We studied antiparietal cell antibody (anti-PCA) and anti-intrinsic factor antibody (anti-IFA) levels and their associations with pepsinogen I/pepsinogen II levels in patients with gastric adenocarcinoma compared to a control group with mild or no atrophy of the stomach mucosa. Plasma levels of anti-PCA and anti-IFA were measured by ELISA (Inova Diagnostics Inc, San Diego, California, USA). The cutoff value for anti-PCA and anti-IFA positivity was ≥25 units. Altogether 214 patients (126 men, 88 women, median age 64.46, range: 35-86) with confirmed gastric adenocarcinoma and 214 control cases paired for age and sex were included in the study. Positive anti-PCA was present in 22 (10.3%) gastric cancer patients and controls (P ≥ 0.999); positive anti-IFA in 6 (2.8%) and 4 (1.9.%), P < 0.232, respectively. We did not find significant differences in anti-PCA and anti-IFA positivity between gastric cancer patients and the control group; further investigation is required to better understand the potential involvement of autoimmune gastritis in the development of gastric cancer.

Serum anti-tissue transglutaminase IgA and prediction of duodenal villous atrophy in adults with suspected coeliac disease without IgA deficiency (Bi.A.CeD): a multicentre, prospective cohort study

BACKGROUND

Whether coeliac disease in adults can be diagnosed with serology alone remains controversial. We aimed to evaluate the accuracy of serum anti-tissue transglutaminase IgA (tTG-IgA) in the diagnosis of coeliac disease.

METHODS

In this multicentre, prospective cohort study, adult participants (aged ≥18 years) with suspected coeliac disease without IgA deficiency who were not on a gluten-free diet and who had a local serum tTG-IgA measurement, were enrolled from Feb 27, 2018, to Dec 24, 2020, by 14 tertiary referral centres (ten from Europe, two from Asia, one from Oceania, and one from South America) to undergo local endoscopic duodenal biopsy. Local serum tTG-IgA was measured with 14 different test brands and concentration expressed as a multiple of each test's upper limit of normal (ULN), and defined as positive when greater than 1 times the ULN. The main study outcome was the reliability of serum tests for the diagnosis of coeliac disease, as defined by duodenal villous atrophy (Marsh type 3 or Corazza-Villanacci grade B). Histology was evaluated by the local pathologist, with discordant cases (positive tTG-IgA without duodenal villous atrophy or negative tTG-IgA with duodenal villous atrophy) re-evaluated by a central pathologist. The reliability of serum tests for the prediction of duodenal villous atrophy was evaluated according to sensitivity, specificity, positive predictive value, negative predictive value, and the area under the receiver operating characteristic curve (AUC) for categorical and continuous data.

FINDINGS

We enrolled 436 participants with complete local data on serum tTG-IgA and duodenal histology (296 [68%] women and 140 [32%] men; mean age 40 years [SD 15]). Positive serum tTG-IgA was detected in 363 (83%) participants and negative serum tTG-IgA in 73 (17%). Of the 363 participants with positive serum tTG-IgA, 341 had positive histology (true positives) and 22 had negative histology (false positives) after local review. Of the 73 participants with negative serum tTG-IgA, seven had positive histology (false negatives) and 66 had negative histology (true negatives) after local review. The positive predictive value was 93·9% (95% CI 89·2-98·6), the negative predictive value was 90·4% (85·5-95·3), sensitivity was 98·0% (95·3-100·0), and specificity was 75·0% (66·6-83·4). After central re-evaluation of duodenal histology in 29 discordant cases, there were 348 true positive cases, 15 false positive cases, 66 true negative cases, and seven false negative cases, resulting in a positive predictive value of 95·9% (92·0-99·8), a negative predictive value of 90·4% (85·5-95·3), a sensitivity of 98·0% (95·3-100·0), and a specificity of 81·5% (73·9-89·1). Either using the local or central definition of duodenal histology, the positive predictive value of local serum tTG-IgA increased when the serological threshold was defined at increasing multiples of the ULN (p<0·0001). The AUC for serum tTG-IgA for the prediction of duodenal villous atrophy was 0·87 (95% CI 0·81-0·92) when applying the categorical definition of serum tTG-IgA (positive [>1 × ULN] vs negative [≤1 × ULN]), and 0·93 (0·89-0·96) when applying the numerical definition of serum tTG-IgA (multiples of the ULN). Additional endoscopic findings included peptic gastritis (nine patients), autoimmune atrophic gastritis (three), reflux oesophagitis (31), gastric or duodenal ulcer (three), and Barrett's oesophagus (one). In the 1-year follow-up, a midgut ileum lymphoma was diagnosed in a woman on a gluten-free diet.

INTERPRETATION

Our data showed that biopsy could be reasonably avoided in the diagnosis of coeliac disease in adults with reliable suspicion of coeliac disease and high serum tTG-IgA.

FUNDING

None.

Prevalence of Antiphospholipid Antibodies and Association With Incident Cardiovascular Events

Importance

The prevalence of antiphospholipid antibodies (aPL) and their association with future atherosclerotic cardiovascular disease (ASCVD) risk has yet to be thoroughly investigated.

Objective

To determine the association between measurements of aPL at a single time point and ASCVD risk in a diverse population.

Design, Setting, and Participants

This cohort study measured 8 aPL (anticardiolipin [aCL] IgG/IgM/IgA, anti-beta-2 glycoprotein I [aβ2GPI] IgG/IgM/IgA, and antiphosphatidylserine/prothrombin [aPS/PT] IgG/IgM) by solid-phase assays in plasma from participants of the Dallas Heart Study (DHS) phase 2, a multiethnic, population-based cohort study. Blood samples were collected between 2007 and 2009. The median follow-up was 8 years. Statistical analysis was performed from April 2022 to January 2023.

Main Outcomes and Measures

Associations of aPL with future ASCVD events (defined as first nonfatal myocardial infarction, first nonfatal stroke, coronary revascularization, or death from cardiovascular cause) were assessed by Cox proportional hazards models, adjusting for known risk factors, medications, and multiple comparisons.

Results

Among the 2427 participants (mean [SD] age, 50.6 [10.3] years; 1399 [57.6%] female; 1244 [51.3%] Black, 339 [14.0%] Hispanic, and 796 [32.8%] White), the prevalence of any positive aPL tested at a single time point was 14.5% (353 of 2427), with approximately one-third of those detected at a moderate or high titer; aCL IgM had the highest prevalence (156 individuals [6.4%]), followed by aPS/PT IgM (88 [3.4%]), aβ2GPI IgM (63 [2.6%]), and aβ2GPI IgA (62 [2.5%]). The IgA of aCL (adjusted hazard ratio [HR], 4.92; 95% CI, 1.52-15.98) and aβ2GPI (HR, 2.91; 95% CI, 1.32-6.41) were independently associated with future ASCVD events. The risk further increased when applying a positivity threshold of at least 40 units (aCL IgA: HR, 9.01 [95% CI, 2.73-29.72]; aβ2GPI IgA: HR, 4.09 [95% CI, 1.45-11.54]). Levels of aβ2GPI IgA negatively correlated with cholesterol efflux capacity (r = -0.055; P = .009) and positively correlated with circulating oxidized LDL (r = 0.055; P = .007). aβ2GPI IgA-positive plasma was associated with an activated endothelial cell phenotype as evidenced by increased surface expression of surface E-selectin, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1.

Conclusions and Relevance

In this population-based cohort study, aPL detectable by solid-phase assays were present in a substantial proportion of adults; positive aCL IgA and aβ2GPI IgA at a single time point were independently associated with future ASCVD events. Longitudinal studies with serial aPL measurements are needed to further explore these findings.

Clinical utility of circulating calprotectin to assist prediction and monitoring of COVID-19 severity: An Italian study

BACKGROUND

Calprotectin (S100A8/A9) has been identified as a biomarker that can aid in predicting the severity of disease in COVID-19 patients. This study aims to evaluate the correlation between levels of circulating calprotectin (cCP) and the severity of COVID-19.

METHODS

Sera from 245 COVID-19 patients and 110 apparently healthy individuals were tested for calprotectin levels using a chemiluminescent immunoassay (Inova Diagnostics). Intensive care unit (ICU) admission and type of respiratory support administered were used as indicators of disease severity, and their correlation with calprotectin levels was assessed.

RESULTS

Samples from patients in the ICU had a median calprotectin concentration of 11.6 µg/ml as compared to 3.5 µg/ml from COVID-19 patients who were not in the ICU. The median calprotectin concentration in a cohort of healthy individuals collected before the COVID-19 pandemic was 3.0 µg/ml (95% CI: 2.820-2.969 µg/ml). Patients requiring a Venturi mask, continuous positive airway pressure, or orotracheal intubation all had significantly higher values of calprotectin than controls, with the increase of cCP levels proportional to the increasing need of respiratory support.

CONCLUSION

Calprotectin levels in serum correlate well with disease severity and represent a promising serological biomarker for the risk assessment of COVID-19 patients.

Anti-HMGCR myopathy overlaps with dermatomyositis-like rash: a distinct subtype of idiopathic inflammatory myopathy

OBJECTIVE

To characterize the clinical and pathological features of anti-HMGCR myopathy.

METHODS

The presence of anti-HMGCR antibody in the serum of 227 patients with idiopathic inflammatory myopathy (IIM) and 100 healthy control individuals was assessed by ELISA. All ELISA positive samples were retested by indirect immunofluorescence assay (IIFA) on HEK293 cells. The clinical findings, muscle pathological features, and treatment outcomes of patients with anti-HMGCR myopathy, along with comparisons between anti-HMGCR myopathy with and without dermatomyositis (DM)-like skin rashes, and among MSA-based subgroups were analyzed.

RESULTS

We established an optimized ELISA cutoff for anti-HMGCR antibody positivity as ≥ 5.28 U. The overall concordance between ELISA and IIFA was 96.83%. Twenty-one out of 227 IIM patients were anti-HMGCR-positive by both assays. Of these 21 patients, 9 had DM-like skin rashes, and 16 showed remarkable muscle inflammation; 5 patients were juvenile-onset, and 2 received statin treatment. The muscle biopsies from these patients demonstrated variable muscle necrosis and T cell infiltration. Most anti-HMGCR-positive patients achieved favorable outcomes following prednisone and additional immunotherapies. The anti-HMGCR myopathy patients with DM-like rashes, compared to those without DM-like rashes, were younger and had a shorter disease duration.

CONCLUSIONS

Optimization of cutoff of anti-HMGCR antibody assays with confirmation by alternative assays can result in higher sensitivity and specificity. DM-like skin rashes and lymphocytic infiltrates were not rare in patients with anti-HMGCR myopathy. These findings suggest that while anti-HMGCR myopathy may overlap with DM-like rash, it is pathologically different from classic DM, and should be considered a distinct subgroup of IIM.

Anti-Phosphatidylserine/Prothrombin Antibodies at Two Points: Correlation With Lupus Anticoagulant and Thrombotic Risk

Antibodies to phospholipids (aPL) and associated proteins are a hallmark in the diagnosis of anti-phospholipid syndrome (APS). Those included in the classification criteria are the lupus anticoagulant (LA) and the IgG and IgM isotypes of anticardiolipin (aCL) and anti-beta-2 glycoprotein I (β2GPI) antibodies. Non-classification criteria markers such as autoantibodies that recognize the phosphatidylserine/prothrombin (aPS/PT) complex have been proposed as biomarkers for APS. Studies of aPS/PT antibodies have shown a strong correlation to clinical manifestations and LA. We aimed to study the value and the persistence of aPS/PT IgG and IgM antibodies in a cohort of consecutive patients with clinical suspicion of APS and their utility as thrombotic risk markers. Our study, with 103 patients, demonstrates that persistently positive results for aPS/PT IgG antibodies were significantly associated with APS classification, thrombosis, triple aPL positivity, LA positive result, and the Global APS Score (GAPSS) > than 9 points (p < 0.01, for each condition). On the other hand, no association was seen with pregnancy morbidity (p = 0.56) and SLE (p = 0.07). Persistence of aPS/PT antibodies, defined according to the current laboratory classification criteria, likely improves the diagnosis and clinical assessment of patients with APS.

Gluten-Free Diet Reduces Symptoms, Particularly Diarrhea, in Patients With Irritable Bowel Syndrome and Antigliadin IgG

BACKGROUND & AIMS

Many patients with irritable bowel syndrome (IBS) perceive that their symptoms are triggered by wheat-containing foods. We assessed symptoms and gastrointestinal transit before and after a gluten-free diet (GFD) in unselected patients with IBS and investigated biomarkers associated with symptoms.

METHODS

We performed a prospective study of 50 patients with IBS (ROME III, all subtypes), with and without serologic reactivity to gluten (antigliadin IgG and IgA), and 25 healthy subjects (controls) at a university hospital in Hamilton, Ontario, Canada, between 2012 and 2016. Gastrointestinal transit, gut symptoms, anxiety, depression, somatization, dietary habits, and microbiota composition were studied before and after 4 weeks of a GFD. HLA-DQ2/DQ8 status was determined. GFD compliance was assessed by a dietitian and by measuring gluten peptides in stool.

RESULTS

There was no difference in symptoms among patients at baseline, but after the GFD, patients with antigliadin IgG and IgA reported less diarrhea than patients without these antibodies (P = .03). Compared with baseline, IBS symptoms improved in 18 of 24 patients (75%) with antigliadin IgG and IgA and in 8 of 21 patients (38%) without the antibodies. Although constipation, diarrhea, and abdominal pain were reduced in patients with antigliadin IgG and IgA, only pain decreased in patients without these antibodies. Gastrointestinal transit normalized in a higher proportion of patients with antigliadin IgG and IgA. Anxiety, depression, somatization, and well-being increased in both groups. The presence of antigliadin IgG was associated with overall reductions in symptoms (adjusted odds ratio compared with patients without this antibody, 128.9; 95% CI, 1.16-1427.8; P = .04). Symptoms were reduced even in patients with antigliadin IgG and IgA who reduced gluten intake but were not strictly compliant with the GFD. In controls, a GFD had no effect on gastrointestinal symptoms or gut function.

CONCLUSIONS

Antigliadin IgG can be used as a biomarker to identify patients with IBS who might have reductions in symptoms, particularly diarrhea, on a GFD. Larger studies are needed to validate these findings. ClinicalTrials.gov: NCT03492333.

Anti-glycoprotein 2 (anti-GP2) IgA and anti-neutrophil cytoplasmic antibodies to serine proteinase 3 (PR3-ANCA): antibodies to predict severe disease, poor survival and cholangiocarcinoma in primary sclerosing cholangitis

BACKGROUND

Primary sclerosing cholangitis (PSC) is associated with progressive liver disease and cholangiocarcinoma. Although risk stratification is crucial for making clinical decisions, it is hindered by a scarcity of proven prognostic markers.

AIMS

To assess the value of novel anti-glycoprotein 2 (anti-GP2) and anti-neutrophil cytoplasmic antibodies to serine proteinase 3 (PR3-ANCA) in combination with PSC-specific clinical and laboratory markers as predictors of quality of life, disease severity, and cholangiocarcinoma in two large, independent cohorts of PSC patients METHODS: Discovery (338 Polish patients) and validation (178 German patients) cohorts with PSC were evaluated. Anti-GP2 (isoforms 1/4) was detected by ELISAs and PR3-ANCA by chemiluminescence immunoassay. Clinical and laboratory data were collected and analysed. The outcome was defined as liver transplantation-free survival and occurrence of cholangiocarcinoma during follow-up.

RESULTS

In the discovery group, anti-GP2_1/4 IgA and PR3-ANCA were associated with liver dysfunction, anti-GP2_1/4 IgA with risk scores for PSC and anti-GP2₄ IgA with cirrhosis. All cholangiocarcinoma patients were positive for PR3-ANCA and/or anti-GP2₄ IgA. The association between anti-GP2 IgA and liver biochemistry, risk scores, cirrhosis, impaired survival, and cholangiocarcinoma was confirmed in the validation cohort. Cox proportional-hazards regression indicated anti-GP2₁ IgA as an independent variable of poor outcome in both study cohorts. Analysis of the combined data showed that anti-GP2₄ IgA and PR3-ANCA were independent predictors for cholangiocarcinoma, while anti-GP2₁ IgA and PR3-ANCA were indicators for poor survival.

CONCLUSIONS

Anti-GP2 and PR3-ANCA are prognostic antibodies in PSC as they identify patients at risk of severe disease, poor survival and biliary cancer.

Novel Anti-Hexokinase 1 Antibodies Are Associated With Poor Prognosis in Patients With Primary Biliary Cholangitis

INTRODUCTION

Antibodies to hexokinase 1 (HK1) and kelch-like 12 (KLHL12) have been identified as potential biomarkers in primary biliary cholangitis (PBC), and this study assesses changes of these antibodies over time and if they are associated with clinical outcomes.

METHODS

Two hundred fifty-four PBC patients (93.3% female, 51 ± 12.3 years old) were tested for anti-HK1 and anti-KLHL12, antimitochondrial (AMA), anti-gp210, and anti-sp100 antibodies. One hundred sixty-nine patients were tested twice and 49 three times within 4.2 (0.8-10.0) years. Biochemistry and clinical features at diagnosis, response to therapy, events of decompensation, and liver-related death or transplantation were evaluated.

RESULTS

Anti-HK1 and anti-KLHL2 were detected in 46.1% and 22.8% patients, respectively. AMA were positive in 93.7%, anti-sp100 in 26.4%, and anti-gp210 in 21.3% of patients. Anti-HK1 and anti-KLHL12 positivity changed over time in 13.3% and 5.5% of patients, respectively. Anti-HK1 or anti-KLHL12 were present in 37.5% of AMA-negative patients, and in 40% of AMA, anti-gp210, and anti-sp100 negative. No significant differences were observed between those with or without HK1 and KLHL12 antibodies, but transplant-free survival and time to liver decompensation were significantly lower in patients anti-HK1 positive (P = 0.039; P = 0.04) and in those anti-sp100 positive (P = 0.01; P = 0.007). No changes in survival and events of liver decompensation were observed according to the positivity of AMA, anti-KLHL12, or anti-gp210 antibodies.

DISCUSSION

HK1 and KLHL12 antibodies are present in 40% of PBC patients who are seronegative by the conventional PBC-specific antibodies. The novel antibodies remain rather steady during the course of the disease, and HK1 antibodies are associated with unfavourable outcomes.

Golgi protein-73: A biomarker for assessing cirrhosis and prognosis of liver disease patients

BACKGROUND

Reliable biomarkers of cirrhosis, hepatocellular carcinoma (HCC), or progression of chronic liver diseases are missing. In this context, Golgi protein-73 (GP73) also called Golgi phosphoprotein-2, was originally defined as a resident Golgi type II transmembrane protein expressed in epithelial cells. As a result, GP73 expression was found primarily in biliary epithelial cells, with only slight detection in hepatocytes. However, in patients with acute or chronic liver diseases and especially in HCC, the expression of GP73 is significantly up-regulated in hepatocytes. So far, few studies have assessed GP73 as a diagnostic or prognostic marker of liver fibrosis and disease progression.

AIM

To assess serum GP73 efficacy as a diagnostic marker of cirrhosis and/or HCC or as predictor of liver disease progression.

METHODS

GP73 serum levels were retrospectively determined by a novel GP73 ELISA (QUANTA Lite^® GP73, Inova Diagnostics, Inc., Research Use Only) in a large cohort of 632 consecutive patients with chronic viral and non-viral liver diseases collected from two tertiary Academic centers in Larissa, Greece (n = 366) and Debrecen, Hungary (n = 266). Aspartate aminotransferase (AST)/Platelets (PLT) ratio index (APRI) was also calculated at the relevant time points in all patients. Two hundred and three patients had chronic hepatitis B, 183 chronic hepatitis C, 198 alcoholic liver disease, 28 autoimmune cholestatic liver diseases, 15 autoimmune hepatitis, and 5 with other liver-related disorders. The duration of follow-up was 50 (57) mo [median (interquartile range)]. The development of cirrhosis, liver decompensation and/or HCC during follow-up were assessed according to internationally accepted guidelines. In particular, the surveillance for the development of HCC was performed regularly with ultrasound imaging and alpha-fetoprotein (AFP) determination every 6 mo in cirrhotic and every 12 mo in non-cirrhotic patients.

RESULTS

Increased serum levels of GP73 (> 20 units) were detected at initial evaluation in 277 out of 632 patients (43.8%). GP73-seropositivity correlated at baseline with the presence of cirrhosis (96.4% vs 51.5%, P < 0.001), decompensation of cirrhosis (60.3% vs 35.5%, P < 0.001), presence of HCC (18.4% vs 7.9%, P < 0.001) and advanced HCC stage (52.9% vs 14.8%, P = 0.002). GP73 had higher diagnostic accuracy for the presence of cirrhosis compared to APRI score [Area under the curve (AUC) (95%CI): 0.909 (0.885-0.934) vs 0.849 (0.813-0.886), P = 0.003]. Combination of GP73 with APRI improved further the accuracy (AUC: 0.925) compared to GP73 (AUC: 0.909, P = 0.005) or APRI alone (AUC: 0.849, P < 0.001). GP73 levels were significantly higher in HCC patients compared to non-HCC [22.5 (29.2) vs 16 (20.3) units, P < 0.001) and positively associated with BCLC stage [stage 0: 13.9 (10.8); stage A: 17.1 (16.8); stage B: 19.6 (22.3); stage C: 32.2 (30.8); stage D: 45.3 (86.6) units, P < 0.001] and tumor dimensions [very early: 13.9 (10.8); intermediate: 19.6 (18.4); advanced: 29.1 (33.6) units, P = 0.004]. However, the discriminative ability for HCC diagnosis was relatively low [AUC (95%CI): 0.623 (0.570-0.675)]. Kaplan-Meier analysis showed that the detection of GP73 in patients with compensated cirrhosis at baseline, was prognostic of higher rates of decompensation (P = 0.036), HCC development (P = 0.08), and liver-related deaths (P < 0.001) during follow-up.

CONCLUSION

GP73 alone appears efficient for detecting cirrhosis and superior to APRI determination. In combination with APRI, its diagnostic performance can be further improved. Most importantly, the simple GP73 measurement proved promising for predicting a worse outcome of patients with both viral and non-viral chronic liver diseases.

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.

Anti–Domain I β2-Glycoprotein I Antibodies and Activated Protein C Resistance Predict Thrombosis in Antiphospholipid Syndrome: TAC(I)T Study

Background

Antibodies binding to domain I of β2-glycoprotein I (aDI) and activated protein C (APC) resistance are associated with an increased risk of thrombosis in cross-sectional studies. The objective of this study was to assess their predictive value for future thromboembolic events in patients with antiphospholipid antibodies (aPL) or antiphospholipid syndrome.

Methods

This prospective multicenter cohort study included consecutive patients with aPL or systemic lupus erythematosus. We followed 137 patients (43.5 ± 15.4 year old; 107 women) for a mean duration of 43.1 ± 20.7 months.

Results

We detected aDI IgG antibodies by ELISA in 21 patients. An APC sensitivity ratio (APCsr) was determined using a thrombin generation–based test. The APCsr was higher in patients with anti–domain I antibodies demonstrating APC resistance (0.75 ± 0.13 vs 0.48 ± 0.20, P &lt; 0.0001). In univariate analysis, the hazard ratio (HR) for thrombosis over time was higher in patients with aDI IgG (3.31 [95% CI, 1.15–9.52]; P = 0.03) and patients with higher APC resistance (APCsr &gt;95th percentile; HR, 6.07 [95% CI, 1.69–21.87]; P = 0.006). A sensitivity analysis showed an increased risk of higher aDI IgG levels up to HR 5.61 (95% CI, 1.93–16.31; P = 0.01). In multivariate analysis, aDI IgG (HR, 3.90 [95% CI, 1.33–11.46]; P = 0.01) and APC resistance (HR, 4.98 [95% CI, 1.36–18.28]; P = 0.02) remained significant predictors of thrombosis over time.

Conclusions

Our study shows that novel tests for antibodies recognizing domain I of β2-glycoprotein I and functional tests identifying APC resistance are significant predictors of thrombosis over time and may be useful for risk stratification.

Evaluation of a novel extended automated particle-based multi-analyte assay for the detection of autoantibodies in the diagnosis of primary biliary cholangitis

Background

Anti-mitochondrial autoantibodies (AMA) detected by indirect immunofluorescence (IIF) on rodent tissues are the diagnostic marker of primary biliary cholangitis (PBC). However, up to 15% of patients with PBC are AMA-negative by IIF. In the effort to close the serological gap and improve the diagnostic sensitivity of PBC testing, recently, novel autoantibodies specific for PBC, such as kelch-like 12 (KLHL12, KLp epitope) and hexokinase 1 (HK1) have been described. In this study, we evaluated the autoantibody profile in a large cohort of PBC patients and in patients with other liver disease, including anti-HK1 and anti-KLp autoantibodies.

Methods

Sera of 194 PBC patients (126 AMA-IIF-positive and 68 AMA-IIF-negative) and 138 disease controls were tested for a panel of PBC-specific antibodies (MIT3, sp100, gp210, HK1, KLp) using a new automated particle-based multi-analyte technology (PMAT) assay on the Aptiva instrument (Inova).

Results

Selecting a cutoff yielding a specificity of >95% for all the markers, the sensitivity for anti-MIT3, anti-sp100, anti-gp210, anti-HK1 and anti-KLp in the PBC AMA-IIF-negative cohort was 20.6%, 16.2%, 23.5%, 22.0%, 17.6 and 13.2%, respectively. Six out of the 68 (8.8%) AMA-IIF negative sera were positive for anti-HK1 or anti-KLp alone. Using these new markers in addition to anti-MIT3, anti-sp100 and anti-gp210, the overall sensitivity in this cohort of AMA-IIF-negative patients increased from 53% to 61.8%, reducing the serological gap in AMA-negative PBC patients.

Conclusions

PBC antibody profiling, made possible by the new Aptiva-PMAT technology, allows recognition of a higher number of AMA-negative PBC patients than conventional immunoassays and may represent a useful tool to evaluate the prognostic significance of autoantibody association in PBC patients.

"Non-criteria" antiphospholipid antibodies add value to antiphospholipid syndrome diagnoses in a large Chinese cohort

BACKGROUND

Despite expansion in the 2006 Sydney antiphospholipid syndrome (APS) classification criteria to include IgG/IgM anti-β2-glycoprotein (aβ2GPI) antibodies in addition to IgG/IgM anti-cardiolipin antibodies (aCL) and lupus anticoagulant (LAC), some individuals with clinical features of APS remain seronegative (seronegative APS or SNAPS) and are at risk of recurrent thrombosis and pregnancy morbidities. Our aim was to assess the value of "non-criteria" aPL antibodies to detect these SNAPS patients.

METHODS

One hundred ninety-two APS patients, 90 SNAPS patients, 193 autoimmune disease controls, and 120 healthy controls were evaluated. Ten antiphospholipid antibodies (aPLs) were tested using commercial kits, including 5 non-criteria aPLs: anti-phosphatidylserine/prothrombin antibodies (aPS/PT) IgG/IgM, aCL IgA, aβ2GPI IgA, and anti-β2GPI Domain 1 (aβ2GPI-D1) IgG.

RESULTS

Up to 60.9% of the SNAPS and 93.5% of APS patients were detected by at least one non-criteria aPL. aPS/PT IgG had the highest Youden index in classifying APS and SNAPS from controls. aPS/PT IgG and aβ2GPI Domain 1 IgG seem to be the most significant risk factors for thrombotic events and pregnancy morbidity, respectively. aPS/PT IgG/IgM and aβ2GPI-D1 IgG were detected in some SNAPS patients, while IgA isotypes of aCL/aβ2GPI tended to appear together with other biomarkers. The combined analysis showed enhanced diagnostic performance with the inclusion of non-criteria aPLs.

CONCLUSIONS

Recognition of SNAPS patients is critical for clinical management and prevention of potential thrombotic and obstetric adverse events. The non-criteria antiphospholipid antibodies help to identify a considerable portion (60.9%) of these patients who otherwise may remain untreated and at clinical risk.

Clinical performance of automated chemiluminescent methods for anticardiolipin and anti-β2-glycoprotein I antibodies detection in a large cohort of Chinese patients with antiphospholipid syndrome

INTRODUCTION

To assess the clinical performance and correlations of automated chemiluminescence assay (CIA) and enzyme-linked immunosorbent assay (ELISA) for detecting antiphospholipid (aPL) antibodies in the diagnosis of antiphospholipid syndrome (APS).

METHODS

The study recruited 505 subjects, including 192 with APS, 193 with connective tissue diseases other than APS, and 120 healthy donors. We measured anticardiolipin (aCL) and anti-β2-glycoprotein I (anti-β2GPI) antibodies IgG, IgM, and IgA in all the samples using both CIA and ELISA.

RESULTS

Total agreement between the two methods ranged from 83.50% for anti-β2GPI IgG antibodies to 92.76% for anti-β2GPI IgM antibodies in all the groups. Anti-β2GPI and aCL IgG assays showed the highest Spearman's rho coefficients (anti-β2GPI IgG = 0.742, aCL IgG = 0.715). Anti-β2GPI IgG CIA showed the highest sensitivity for diagnosis of APS at 80.21%, which was significantly higher than the sensitivity of anti-β2GPI IgG ELISA (52.08%). For diagnosis of APS, anti-β2GPI IgG CIA had the best discrimination power with the area under the curves (AUC) of 0.922, followed by aCL IgG CIA (AUC of 0.905). While the CIA AUC was slightly higher in all cases, the difference was not statistically significant.

CONCLUSION

CIA measurements had a good agreement and correlation with comparative ELISA assays. The CIA anti-β2GPI IgG however was significantly more sensitive for APS diagnosis. The two assay methodologies showed comparable predictive powers and support the value of the CIA method for improved diagnosis and management of patients with APS.

Anti-β2GPI domain 1 antibodies stratify high risk of thrombosis and late pregnancy morbidity in a large cohort of Chinese patients with antiphospholipid syndrome

INTRODUCTION

Anti-β2GPI-Domain 1 (β2GPI-D1) antibodies are considered to be a pathogenic subset of anti-β2GPI antibodies and have been strongly associated with thrombosis and pregnancy morbidity in patients with antiphospholipid syndrome (APS). We evaluated the clinical utility of anti-β2GPI-D1 IgG antibodies for stratifying the risk of thrombosis and/or pregnancy morbidity (PM) in a cohort of Chinese patients with APS and also assessed its correlation with the Global Anti-Phospholipid Syndrome Score (GAPSS).

MATERIALS AND METHODS

Sera and plasma from 192 consecutive APS patients, 17 aPL carriers, 193 patients with other systemic autoimmune diseases, and 120 healthy controls were collected and the presence of aCL IgG/IgM, anti-β2GPI IgG/IgM and anti-β2GPI-D1 IgG antibodies were assessed by chemiluminescence assays (CIA). Detection of LAC was performed according to international guidelines with the use of screening, mixing and confirmation tests. Anti-phosphatidylserine-prothrombin (aPS/PT) IgG and IgM antibodies were detected by commercial ELISA kits.

RESULTS

Anti-β2GPI-D1 IgG antibodies showed high specificity (97.12%) and moderate sensitivity (64.32%) for the diagnosis of APS. Anti-β2GPI-D1 antibodies levels were significantly higher in patients with triple aPL positivity than in those with double (P < 0.001) and single positive aPL (P < 0.001) and correlated well with the GAPSS (rho = 0.60, P < 0.001). Anti-β2GPI-D1 antibodies presented with a higher prevalence and higher titers in patients with late pregnancy morbidity (≥10 weeks) and thrombotic APS compared to those with early pregnancy (<10 weeks) morbidity. Higher anti-β2GP1-D1 antibodies titers effectively distinguished APS from other autoimmune diseases.

CONCLUSION

This study suggests a predictive role of anti-β2GPI-D1 IgG antibodies as a strong risk factor for both thrombotic and obstetric APS (OAPS), especially for stratification comparing early PM with late PM and thrombosis.

KIR/HLA genotypes confer susceptibility and progression in patients with autoimmune hepatitis

Natural killer (NK) cells are key participants in the innate immune response. Killer cell immunoglobulin-like receptors (KIRs) are involved in the activation and inhibition of NK cells through the recognition of human leukocyte antigen (HLA) class I molecules. We investigated the impact of KIR/HLA combinations on susceptibility and long-term clinical outcome in Japanese patients with type 1 autoimmune hepatitis (AIH).

Methods

A total of 154 cases of AIH were recruited at Shinshu University Hospital between 1974 and 2018. KIR genes and HLA class I and II alleles were genotyped in all patients along with 201 healthy individuals. Associations between KIR/HLA pairs and clinical outcomes (liver decompensation and liver-related death) were evaluated using the Cox proportional hazards model with stepwise method.

Results

After a median follow-up period of 11.1 years, 12% of patients experienced liver decompensation and 8% died from liver disease. KIR3DL1/HLA-B Bw4-80Ile (p = 0.0062) and the HLA-DRB1*04:05-DQB1*04:01 haplotype (p ≪0.001) were significantly associated with AIH. Conversely, significant protective associations were found for KIR3DL1/HLA-B Bw4-80Thr (p = 0.0092) and KIR2DL1/HLA-C2 (p = 0.0025). The KIR3DL1/HLA-B Bw4-positive phenotype was strongly associated with a favorable clinical outcome (liver decompensation: hazard ratio [HR] 0.37, p = 0.037; liver-related death: HR 0.26, p = 0.038). Cirrhosis was detected in 16 (10%) patients at diagnosis and was significantly related to poor survival (HR 17.87, p ≪0.001) and progression to liver decompensation (HR 9.00, p ≪0.001).

Conclusions

This study revealed the impact of specific KIR/HLA pairs in AIH susceptibility and progression in Japanese patients. KIR3DL1/HLA-B Bw4-negative patients with AIH and cirrhosis at diagnosis are at high risk of adverse outcomes and require careful surveillance.

Lay summary

Autoimmune hepatitis (AIH) is a disease of the liver that can present in acute or chronic hepatitis. We examined whether KIR/HLA pairs were associated with AIH susceptibility or disease progression. KIR3DL1/HLA-B Bw4 was a novel KIR/HLA pair related to a favorable clinical outcome, while cirrhosis at the initial diagnosis was a risk factor for poor prognosis. Thus, frequent and careful surveillance is advised for KIR3DL1/HLA-B Bw4-negative patients with AIH and cirrhosis.

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KIR3DL1/HLA-B Bw4-80Ile is significantly associated with autoimmune hepatitis.

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KIR2DL1/HLA-C2 and KIR3DL1/HLA-B Bw4-80Thr have protective associations with autoimmune hepatitis.

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KIR3DL1/HLA-B Bw4 is a novel KIR/HLA pair related to a favorable outcome in autoimmune hepatitis.

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Combined KIR3DL1/HLA-B Bw4 and cirrhosis at diagnosis relate to autoimmune hepatitis progression.

Autoantibodies in patients with interleukin 12 receptor beta 1 deficiency

OBJECTIVE

Interleukin 12 receptor beta 1 (IL-12Rβ1) deficiency is a primary immunodeficiency that exposes affected individuals to an augmented risk of intracellular pathogen-mediated infections. The paradoxical presence of autoimmune manifestations in immune-deficient patients has been recognized, but the basis of this phenomenon is unclear, with the role of frequent infections being a possible trigger to break tolerance. Our study aimed to analyze extensively a profile of autoantibodies in a clinically well-defined case series of patients with IL-12Rβ1 deficiency.

METHODS

Eight patients with IL-12Rβ1 deficiency referred to Children's Medical Center in Tunis, Tunisia, during 1995-2012 were enrolled in the study. Sixteen age- and gender-matched blood donors served as controls. Serum, liver-related autoantibodies immunoglobulin (Ig)G, IgM, IgA were tested by ELISA and by standard indirect immunofluorescence on Hep-2 cells.

RESULTS

We found a significant prevalence of liver autoantibodies in the study group. Regarding primary biliary cholangitis (PBC), two of eight patients were positive for MIT3 autoantibodies, both confirmed by immunofluorescence, and one patient was positive for PBC-specific antinuclear antibodies, sp100. Moreover, two patients had significantly increased gamma-glutamyltransferase levels and one had IgM levels twice the upper limit of normal. Intriguingly two patients were positive for anti-actin antibodies; a typical feature of autoimmune hepatitis type 1, along with a significant increase in IgG levels.

CONCLUSIONS

This is the first report of a serological analysis in patients with an IL-12Rβ1 deficiency. Despite the difficulty in interpreting the role of the IL-12, the evidence of liver-specific autoantibodies confirms the importance its signal in liver autoimmunity.

The IgA Isotype of Anti-β2 Glycoprotein I Antibodies Recognizes Epitopes in Domains 3, 4, and 5 That Are Located in a Lateral Zone of the Molecule (L-Shaped)

Background: Antiphospholipid syndrome (APS) is characterized by thrombosis and/or pregnancy morbidity with presence of anti-phospholipid antibodies (aPL). The APS classification criteria only consider the aPL of IgG/IgM isotype, however testing of aPL of IgA isotype is recommended when APS is suspected and consensus aPL are negative. IgA anti-βeta-2 glycoprotein-I (B2GP1) has been clearly related with occurrence of thrombotic events. Antibodies anti-B2GP1 of IgG/M isotypes recognize an epitope in Domain 1 (R39-G43), the epitopes that recognize IgA anti-B2GP1 antibodies are not well-identified. Aim: To determine the zones of B2GP1 recognized by antibodies of IgA isotype from patients with APS symptomatology and positive for IgA anti-B2GP1. Methods: IgA antibodies to Domain-1(D1) and Domain-4/5(D4/5) of B2GP1 (ELISA) and epitope mapping on oligopeptide arrays of B2GP1 were evaluated in sera from a group of 93 patients with at least one thrombotic and with isolated positivity for IgA anti-B2GP1 antibodies (negative for other aPL). Results: A total of 47 patients (50.5%) were positive for anti-D4/5 and 23(25%) were positive for anti-D1. When peptide arrays were analyzed, three zones of B2GP1 reactivity were identified for more than 50% of patients. The center of these zones corresponds to amino acids 140(D3), 204(D4), and 264(D5). The peptides recognized on D3 and D4 contain amino acid sequences sharing high homology with proteins of microorganism that were previously related with a possible APS infectious etiology. In the three-dimensional structure of B2GP1, the three peptides, as the R39-G43 epitope, are located on the right side of the molecule (L-shape). The left side (J-shape) does not bind the antibodies. Conclusions: Patients with thrombotic APS clinical-criteria, and isolated IgA anti-B2GP1 positivity appear to preferentially bind, not to the D1 or D4/5 domains of B2GP1, but rather to three sites in D3, D4, and D5. The sites on D3 and D4 were previously described as the target identified by human monoclonal antibodies derived from patients that were capable of inducing APS in animal models. The localization of these epitopes opens a new route to explore to increase understanding of the patholophysiology of the APS and to propose new alternatives and therapeutic targets.

Anti-C1q autoantibodies are frequently detected in patients with systemic sclerosis associated with pulmonary fibrosis

BACKGROUND

Anti-C1q autoantibodies (autoAbs) are associated with systemic lupus erythematosus (SLE), but their presence in other rheumatic diseases has not been adequately investigated.

OBJECTIVES

We aimed to assess anti-C1q autoAbs and circulating immune complexes (CICs) in systemic sclerosis (SSc).

METHODS

In total 124 patients with SSc were studied; 106 were female and the median age was 59·4 years (range 25-81·4). Overall 75 (60·5%) had limited cutaneous SSc and 49 (39·5%) had diffuse cutaneous SSc. Also included were 25 patients with Sjögren syndrome (SjS), 29 with rheumatoid arthritis (RA), 38 with SLE and 53 healthy controls. Enzyme-linked immunosorbent assays with high- and low-salt buffers were used to measure anti-C1q antibodies and CICs. The former allows only anti-C1q antibody binding to C1q and the latter also allows IgG Fc to bind to C1q.

RESULTS

Anti-C1q antibodies were present in 20 of 124 (16·1%) patients with SSc: five had high levels (> 80 RU mL^-1 ) and 10 (50%) had moderate levels (40-80 RU mL^-1 ). Anti-C1q antibodies were also present in one of 25 (4%) patients with SjS, one of 29 (3%) with RA (P < 0·05 for both) and three of 53 (6%) healthy controls (P < 0·01). Anti-C1q antibodies were detected in 13 of 38 (34%) patients with SLEs. Anti-C1q antibodies were more frequent in male than female patients with SSc (P = 0·005); this association remained after multivariate regression analysis. Anti-C1q antibody level was the most important factor in predicting the presence of pulmonary fibrosis, and the second most important in predicting pulmonary arterial hypertension. Fourteen patients with SSc (11·3%) had CICs.

CONCLUSIONS

Anti-C1q autoAbs were frequently detected in patients with SSc, and their high levels predict the co-occurrence of pulmonary fibrosis or pulmonary arterial hypertension.

Comparison of celiac disease markers in women with early recurrent pregnancy loss and normal controls

PROBLEM

Celiac disease (CD) is an autoimmune intestinal inflammatory disease triggered by gluten in the diet. Untreated CD has been associated with pregnancy loss and infertility. The purpose of this study was to screen unselected women with recurrent pregnancy loss (RPL) for markers of CD to determine whether a correlation exists between RPL and CD serum markers.

METHOD OF STUDY

Frequencies of three serum markers of CD [tissue transglutaminase (TTG) IgA, endomysial (EMA) IgA, and deaminated gliadin peptide (DGP) IgA] were determined by enzyme-linked immunoassay (ELISA). Seven hundred and eight women who had two or more failed clinical pregnancies (cases) and one hundred women with at least one live birth and no miscarriages (controls) were included in this study. All cases had a full workup for RPL based on the American Society for Reproductive Medicine 2013 guidelines. Antiphospholipid antibodies (aPL) were correlated with CD markers based on their potential prothrombotic role. Results The results show no significant difference in the prevalence of CD autoantibodies when comparing the RPL patients with the controls. Over half of the patients who tested positive for serum markers for CD also had positive aPL. Conclusion Screening unselected women with RPL who are asymptomatic for CD is not supported based on these data. Women who test positive for CD may be candidates for aPL testing based on the association of adverse pregnancy outcomes.

The Prevalence of Anti-Hexokinase-1 and Anti-Kelch-Like 12 Peptide Antibodies in Patients With Primary Biliary Cholangitis Is Similar in Europe and North America: A Large International, Multi-Center Study

Primary biliary cholangitis (PBC), formerly known as primary biliary cirrhosis, is present worldwide. Autoantibodies, in particular anti-mitochondrial antibodies (AMA) detected by indirect immunofluorescence assays or newer solid phase immunoassays can detect most, but not all individuals with PBC. Detection of antibodies to the anti-nuclear antigens sp100 and gp210 can identify additional PBC patients, but some seronegative patients remain, often resulting in delayed diagnosis and treatment. Antibodies to kelch-like 12 (KLHL12) and hexokinase 1 (HK-1) were recently identified as new biomarkers for PBC and notably identify patients who are negative for conventional autoantibodies. To become globally adopted, it is important to validate these new biomarkers in different geographic areas. In the present study we evaluated the prevalence of anti-KLHL12 (measured by a KLHL12-derived peptide referred to as KL-p) and anti-HK-1 antibodies by ELISA at five sites within Europe and North America and demonstrated the presence of these antibodies in patients with PBC in all geographies.

Antiphosphatidylserine/prothrombin antibodies (aPS/PT) as potential diagnostic markers and risk predictors of venous thrombosis and obstetric complications in antiphospholipid syndrome

BACKGROUND

The aim of the study was to determine the prevalence and clinical associations of antiphosphatidylserine/prothrombin antibodies (aPS/PT) with thrombosis and pregnancy loss in Chinese patients with antiphospholipid syndrome (APS) and seronegative APS (SNAPS).

METHODS

One hundred and eighty six Chinese patients with APS (67 primary, 119 secondary), 48 with SNAPS, 176 disease controls (79 systemic lupus erythematosus [SLE], 29 Sjogren's syndrome [SS], 30 ankylosing spondylitis [AS], 38 rheumatoid arthritis [RA]) and 90 healthy donors were examined. IgG and IgM aPS/PT, IgG/IgM/IgA anticardiolipin (aCL) and IgG/IgM/IgA anti-β2-glycoprotein I (anti-β2GPI) antibodies were tested by ELISA.

RESULTS

One hundred and sixty (86.0%) of APS patients were positive for at least one aPS/PT isotype. One hundred and thirty five (72.6%) were positive for IgG aPS/PT, 124/186 (66.7%) positive for IgM aPS/PT and 99 (53.2%) positive for both. Approximately half of the SNAPS patients were positive for IgG and/or IgM aPS/PT. Highly significant associations between IgG aPS/PT and venous thrombotic events (odds ratio [OR]=6.72) and IgG/IgM aPS/PT and pregnancy loss (OR=9.44) were found. Levels of IgM aPS/PT were significantly different in APS patients with thrombotic manifestations and those with fetal loss (p=0.014). The association between IgG/IgM aPS/PT and lupus anticoagulant (LAC) was highly significant (p<0.001). When both were positive, the OR for APS was 101.6. Notably, 91.95% (80/87) of LAC-positive specimens were positive for IgG and/or IgM aPS/PT, suggesting aPS/PT is an effective option when LAC testing is not available.

CONCLUSIONS

Anti-PS/PT antibody assays demonstrated high diagnostic performance for Chinese patients with APS, detected some APS patients negative for criteria markers and may serve as potential risk predictors for venous thrombosis and obstetric complications.

The interplay of type I and type II interferons in murine autoimmune cholangitis as a basis for sex-biased autoimmunity

We have reported on a murine model of autoimmune cholangitis, generated by altering the AU-rich element (ARE) by deletion of the interferon gamma (IFN-γ) 3' untranslated region (coined ARE-Del^-/- ), that has striking similarities to human primary biliary cholangitis (PBC) with female predominance. Previously, we suggested that the sex bias of autoimmune cholangitis was secondary to intense and sustained type I and II IFN signaling. Based on this thesis, and to define the mechanisms that lead to portal inflammation, we specifically addressed the hypothesis that type I IFNs are the driver of this disease. To accomplish these goals, we crossed ARE-Del^-/- mice with IFN type I receptor alpha chain (Ifnar1) knockout mice. We report herein that loss of type I IFN receptor signaling in the double construct of ARE-Del^-/- Ifnar1^-/- mice dramatically reduces liver pathology and abrogated sex bias. More importantly, female ARE-Del^-/- mice have an increased number of germinal center (GC) B cells as well as abnormal follicular formation, sites which have been implicated in loss of tolerance. Deletion of type I IFN signaling in ARE-Del^-/- Ifnar1^-/- mice corrects these GC abnormalities, including abnormal follicular structure.

CONCLUSION

Our data implicate type I IFN signaling as a necessary component of the sex bias of this murine model of autoimmune cholangitis. Importantly these data suggest that drugs that target the type I IFN signaling pathway would have potential benefit in the earlier stages of PBC. (Hepatology 2018;67:1408-1419).

Significance of serological markers in the disease course of ulcerative colitis in a prospective clinical cohort of patients

Background & aims

To determine the prognostic potential of classic and novel serologic antibodies regarding unfavorable disease course in a prospective ulcerative colitis (UC) patient cohort, since few and conflicting data are available in the literature regarding this matter.

Methods

187 consecutive patients were studied prospectively (median follow-up: 135 months) from a single referral IBD center in Hungary. Sera were tested for different IgA/IgG type autoantibodies (anti-neutrophil cytoplasmic [ANCA], anti-DNA-bound-lactoferrin [anti-LFS], anti-goblet cell [anti-GAB] and anti-pancreatic [PAB: anti-CUZD1 and anti-GP2)]) by indirect immunofluorescence technique and for anti-microbial (anti-Saccharomyces cerevisiae [ASCA] IgG/IgA and anti-OMP Plus^™ IgA) antibodies by enzyme-linked immunosorbent assays.

Results

A total of 73.6%, 62.4% and 11.2% of UC patients were positive for IgA/IgG type of atypical perinuclear-ANCA, anti-LFS and anti-GAB, respectively. Occurrences of PABs were 9.6%, while ASCA IgA/IgG and anti-OMP IgA were 17.6% and 19.8%, respectively. Antibody status was stable over time. IgA type PABs were more prevalent in patients with primary sclerosing cholangitis (37.5% vs. 4.7% for anti-CUZD1 and 12.5% vs. 0% for anti-GP2, p<0.001 for both). IgA type ASCA and anti-CUZD1 antibodies were associated with higher risk of requirement for long-term immunosuppressant therapy in Kaplan-Meier analysis (pLogRank <0.01 for both). However, in multivariate Cox-regression analysis only ASCA IgA (HR: 2.74, 95%CI: 1.46–5.14, p<0.01) remained independent predictor. UC-related hospitalization due to disease activity was only associated with multiple antibody positivity (for 3 or more; HR 2.03 [95% CI: 1.16–3.56]; p = 0.013). None of the individual antibodies or their combination was associated with the risk of development of extensive disease or colectomy.

Conclusion

Even with low prevalence rates, present study gives further evidence to the role of certain antibodies as markers for distinct phenotype and disease outcome in UC. Considering the result of the multivariate analysis the novel antibodies investigated do not seem to be associated with poor clinical outcome in UC, only a classic antibody, IgA subtype ASCA remained an independent predictor of long-term immunosuppressive therapy.

Antibodies to phosphatidylserine/prothrombin (aPS/PT) enhanced the diagnostic performance in Chinese patients with antiphospholipid syndrome

Background:

Increasing evidence has highlighted the role of non-criteria antiphospholipid antibodies (aPLs) as important supplements to the current criteria aPLs for the diagnosis of antiphospholipid syndrome (APS). In this retrospective study, we evaluated the clinical relevance of antibodies to phosphatidylserine/prothrombin (aPS/PT) in Chinese patients with APS.

Methods:

A total of 441 subjects were tested, including 101 patients with primary APS (PAPS), 140 patients with secondary APS (SAPS), 161 disease controls (DCs) and 39 healthy controls (HCs). Serum IgG/IgM aPS/PT was determined by ELISA.

Results:

The levels of IgG/IgM aPS/PT were significantly increased in patients with APS compared with DCs and HCs. IgG and IgM aPS/PT were present in 29.7% and 54.5% of PAPS, and 42.1% and 53.6% of SAPS, respectively. For diagnosis of APS, IgG aCL exhibited the highest positive likelihood ratio (LR+) of 21.60, followed by LA (13.84), IgG aβ2GP1 (9.19) and IgG aPS/PT (8.49). aPS/PT was detected in 13.3% of seronegative PAPS patients and 31.3% of seronegative SAPS patients. LA exhibited the highest OR of 3.64 in identifying patients with thrombosis, followed by IgG aCL (OR, 2.63), IgG aPS/PT (OR, 2.55) and IgG aβ2GP1 (OR, 2.33). LA and IgG aCL were correlated with both arterial and venous thrombosis, whereas IgG aPS/PT and IgG aβ2GP1 correlated with venous or arterial thrombosis, respectively.

Conclusions:

Our findings suggest that the inclusion of IgG/IgM aPS/PT may enhance the diagnostic performance for APS, especially in those in whom APS is highly suspected, but conventional aPLs are repeatedly negative. In addition, IgG aPS/PT may contribute to identify patients at risk of thrombosis.

Evaluation of classical and novel autoantibodies for the diagnosis of Primary Biliary Cholangitis-Autoimmune Hepatitis Overlap Syndrome (PBC-AIH OS)

Background and aims

Up to 20% of Primary Biliary Cholangitis (PBC) patients are estimated to have features that overlap with Autoimmune Hepatitis (AIH). Patients with PBC-AIH overlap syndrome (PBC-AIH OS) have been reported to exhibit suboptimal responses to ursodeoxycholic acid therapy, and are more likely to progress to cirrhosis. Anti-double stranded DNA (anti-dsDNA) and anti-p53 have been previously suggested to be potential autoantibodies for identifying patients with PBC-AIH OS. In our well defined PBC patient cohorts, a comprehensive assessment of various classical and novel autoantibodies was evaluated for their utility in identifying PBC-AIH OS patients.

Methods

PBC-AIH OS was classified according to the Paris criteria and PBC as per the European Association for the Study of the Liver guidelines. Biobanked serum samples from 197 patients at the University of Calgary Liver Unit and the University of Alberta were analyzed for classical and novel autoantibodies. Anti-dsDNA was measured by the Crithidia luciliae immunofluorescence (CLIFT) assay (1:20 dilution) and chemiluminescence (CIA: QUANTA Flash®, Inova Diagnostics, San Diego). Anti-p53, anti-Ro52/TRIM21, anti-YB 1, anti-GW182, anti-Ge-1, and anti-Ago 2 were measured by either an addressable laser bead immunoassay (ALBIA) or line immunoassay (LIA). Autoantibodies against MIT3, gp210, sp100, LKM1, SLA, and the novel autoantibodies Hexokinase-1 (HK-1), and Kelch like protein 12 (KLHL-12) were measured using QUANTA Lite® ELISA assays. We applied non-parametric methods to compare the biomarkers frequencies between study groups. We used multivariate adjusted models and AUROC to compare the diagnostic accuracy of the different autoantibodies alone or in combination with serum biochemistry.

Results

16 out of 197 PBC patients (8.1%) were classified as PBC-AIH OS. Compared to PBC patients, PBC-AIH OS patients were similar in age (median: 59 vs. 63, P = 0.21) and female predominance (94% vs. 89%, P = 1.00). Anti-dsDNA-by CLIFT (37.5% in PBC-AIH OS vs 9.9% in PBC alone, P <0.01) was the only autoantibody associated with PBC-AIH OS; a finding consistent with previous reports. Significant elevation in serum ALT (62 IU/L in PBC-AIH OS vs 37 IU/L in PBC alone, P < 0.01), and serum IgG (17.6 g/L in OS vs 12.1 g/L in PBC alone, P <0.01) were observed in patients with PBC-AIH OS receiving medical/immunosuppressive therapy. In a multivariate model, positive anti-dsDNA by CLIFT, ALT and IgG were significant predictors of PBC-AIH OS with an area under the receiver operator curve (AUROC) value of 0.84.

Conclusions

Consistent with previous findings, the presence of anti-dsDNA by CLIFT is associated with PBC-AIH OS. Contrary to previous reports, anti-p53 was not associated with PBC-AIH OS. Our comprehensive evaluation of various classical and novel autoantibody biomarkers including Ro52/TRIM21, anti-p53, anti-KLHL-12 and anti-HK-1 were not significantly associated with PBC-AIH OS. Our findings highlight the ongoing need for the research and development of new autoantibody biomarkers to aid in the diagnosis of PBC-AIH OS.

Beyond thrombosis: Anti-β2GPI domain 1 antibodies identify late pregnancy morbidity in anti-phospholipid syndrome

Antibodies against β2 glycoprotein I (anti-β2GPI) have been identified as the main pathogenic autoantibody subset in anti-phospholipid syndrome (APS); the most relevant epitope is a cryptic and conformation-dependent structure on β2GPI domain (D) 1. Anti-β2GPI domain profiling has been investigated in thrombotic APS, leading to the identification of antibodies targeting D1 as the main subpopulation. In contrast, scarce attention has been paid to obstetric APS, hence this study aimed at characterizing the domain reactivity with regards to pregnancy morbidity (PM). To this end, 135 women with persistently positive, medium/high titre anti-β2GPI IgG, without any associated systemic autoimmune diseases and at least one previous pregnancy were included: 27 asymptomatic carriers; 53 women with obstetric APS; 20 women with thrombotic APS; and 35 women with both thrombotic and obstetric complications. Anti-D1 and anti-D4/5 antibodies were tested using a chemiluminescent immunoassay and a research ELISA assay, respectively (QUANTA Flash^® β2GPI Domain 1 IgG and QUANTA Lite^® β2GPI D4/5 IgG, Inova Diagnostics). Positivity for anti-D1 antibodies, but not anti-D4/5 antibodies, was differently distributed across the 4 subgroups of patients (p < 0.0001) and significantly correlated with thrombosis (χ2 = 17.28, p < 0.0001) and PM (χ2 = 4.28, p = 0.039). Patients with triple positivity for anti-phospholipid antibodies displayed higher anti-D1 titres and lower anti-D4/5 titres compared to women with one or two positive tests (p < 0.0001 and p = 0.005, respectively). Reactivity against D1 was identified as a predictor for PM (OR 2.4, 95% confidence interval [CI] 1.2-5.0, p = 0.017); in particular, anti-D1 antibodies were predictive of late PM, conveying an odds ratio of 7.3 (95% CI 2.1-25.5, p = 0.022). Positivity for anti-D1 antibodies was not associated with early pregnancy loss. Anti-D4/5 antibodies were not associated with clinical APS manifestations. As a whole, our data suggest that anti-D1 antibodies are significantly associated not only with thrombosis, but also with late PM, while positive anti-D4/5 antibodies are not predictive of thrombosis or PM.

Comprehensive review of autoantibodies in patients with hyper-IgM syndrome

Hyper-immunoglobulin M syndrome is an X-linked primary immunodeficiency disease caused by mutations in the CD40 ligand gene. The CD40 ligand has been recently highlighted as playing a key role in the pathogenesis of primary biliary cholangitis. In the present study, we assessed an extensive set of serum autoantibodies in a series of well-defined patients with hyper-immunoglobulin M syndrome. Serum, liver-related and liver-not-related autoantibodies IgG, IgM and IgA were tested by ELISA and standard indirect immunofluorescence in HEp-2 cells in 13 Tunisian patients (8 males and 5 females, aged 1-12 years) with hyper-immunoglobulin M syndrome during 1995-2012 and, as controls, 21 age- and gender-matched blood donors. The level of IgM antibody against MIT3 was significantly higher in patients than in controls (35.8 vs 10.7, P=0.002). Half of the hyperimmunoglobulin M syndrome patients were found to be anti-MIT3 IgM positive vs none of the controls (P<0.0001). Twenty-three percent of patients were found to be anti-sp100 antibody positive vs only 0.05% of controls. By immunofluorescence, 92.3% of patients were MIT3 IgM positive vs none of the controls. In conclusion, the IgM class of anti-MIT3 antibodies was shown to be present by both ELISA and immunofluorescence in most of the patients with hyper-immunoglobulin M syndrome. The presence of the hallmark of primary biliary cholangitis, a disease where the CD40 ligand is a key player, in an immunodeficiency disease caused by mutations in the CD40 ligand gene is very intriguing and opens new scenarios in understanding the immune pathogenesis of primary biliary cholangitis.

Closing the Serological Gap in the Antiphospholipid Syndrome: The Value of "Non-criteria" Antiphospholipid Antibodies

OBJECTIVE

Most clinicians use the 2006 Sydney classification criteria to evaluate patients suspected of having antiphospholipid syndrome (APS). Although sensitive and specific for APS, many patients fulfilling clinical criteria for the syndrome are persistently negative for the specific serological tests ("laboratory criteria"). These "seronegative APS" (SN-APS) patients can go undiagnosed and untreated until they experience serious clinical events. This study's objective was to describe antibody profiles of SN-APS patients using non-criteria markers, assess the clinical utility of these markers separately and in combination, and suggest incorporation into guidelines for patients suspected of APS.

METHODS

We categorized 175 consecutive patients suspected of APS into 2 subgroups: 107 fulfilling Sydney APS classification for seropositive APS (SP-APS) and 68 with clinical manifestations suggestive of APS but having negative serology, on 2 occasions, for criteria markers (SN-APS). On study inclusion, samples were retested for criteria and 11 non-criteria markers, including antiphosphatidylserine/prothrombin antibodies.

RESULTS

Using 4 of 11 non-criteria tests, a cumulative 30.9% of SN-APS patients were detected. Combining results of all 11 non-criteria tests, 25 SN-APS (36.8%) and 89 SP-APS (83.2%) were positive for 1 or more non-criteria antibodies.

CONCLUSION

Failure to diagnose APS can result in severe clinical consequences. Patients displaying clinical features of APS, but negative for conventional criteria markers, should undergo additional testing for non-criteria biomarkers. In our cohort, around one-third of SN-APS patients showed reactivity to 1 or more non-criteria markers. An update to the current classification criteria incorporating new serological markers should be considered to identify and stratify patients with APS for more effective treatment and management.

Genetic Risk Factors for Autoimmune Thyroid Disease might Affect the Susceptibility to and Modulate the Progression of Primary Biliary Cholangitis

Background & Aims: Patients with primary biliary cholangitis (PBC) frequently suffer from extrahepatic autoimmune conditions, of which autoimmune thyroid disease (AITD) is one of the most common. Previous studies identified several genetic variants increasing the odds of developing AITD. Here we investigate whether AITD-associated polymorphisms might also play a role in the development and clinical course of PBC and PBC associated with AITD (PBC-AITD).Methods: To this end, we prospectively recruited 230 patients with PBC and 421 healthy controls. Among recruited patients, 64 (30.9%) had PBC-AITD as diagnosed by elevated serum TPO-antibodies. In all subjects we genotyped 10 variants previously associated with AITD.Results: We detected significant associations between the PTPN22 polymorphism and risk of developing PBC (rs2476601, OR=1.43, P=0.035) as well as PBC-AITD (OR=1.74, P=0.028). The IL2RA polymorphism was associated with liver cirrhosis (rs41295061, OR=1.76, P=0.033) whereas the MMEL1 polymorphism increased the risk of requiring liver transplantation (rs2843403, OR=1.70, P=0.023). Although no significant differences in clinical or biochemical characteristics between patients with PBC and PBC-AITD were seen (all P>0.05), liver function tests and metabolic traits in PBC patients were significantly (all P<0.05) affected by the CTLA4 (rs3087243), MMEL1 (rs2843403), PTPN22 (rs2476601) and RNASET2 (rs9355610) variants.Conclusion: Our study demonstrates the existence of a genetic overlap between PBC and AITD. Apparently, genetic variants known to increase the AITD risk might affect the clinical course of PBC. On the other hand, AITD per se does not seem to significantly influence the natural history of PBC.Abbreviations: AITD: autoimmune thyroid disease; ALP: alkaline phosphatase; ALT: alanine transaminase; AMA: anti-mitochondrial autoantibodies; AST: aspartate aminotransferase; DM1: diabetes mellitus type 1; ELISA: enzyme-linked immunosorbent assay method; GGT: gamma-glutamyl transpeptidase; GD: Graves’ disease; GWAS: genome-wide association studies; HT: Hashimoto thyroiditis; HWE: Hardy-Weinberg equilibrium; Lyp: lymphoid-specific protein tyrosine phosphatase non-receptor type 22; OR: odds ratio; PBC: primary biliary cholangitis; RA: rheumatoid arthritis; SLE: systemic lupus erythematosus; TPOAb: thyroid peroxidase antibody; UDCA: ursodeoxycholic acid.

Gut barrier failure biomarkers are associated with poor disease outcome in patients with primary sclerosing cholangitis

AIM

To assess the prevalence of a panel of serologic markers that reflect gut barrier dysfunction in a mixed cohort of pediatric and adult primary sclerosing cholangitis (PSC) patients.

METHODS

Sera of 67 PSC patients [median age (range): 32 (5-79) years, concomitant IBD: 67% and cirrhosis: 20%] were assayed for the presence of antibodies against to F-actin (AAA IgA/IgG) and gliadin (AGA IgA/IgG)] and for serum level of intestinal fatty acid-binding protein (I-FABP) by ELISA. Markers of lipopolysaccharide (LPS) exposure [LPS binding protein (LBP)] and various anti-microbial antibodies [anti-OMP Plus IgA and endotoxin core IgA antibody (EndoCAb)] were also determined. Poor disease outcome was defined as orthotopic liver transplantation and/or liver-related death during the follow-up [median: 99 (14-106) mo]. One hundred and fifty-three healthy subjects (HCONT) and 172 ulcerative colitis (UC) patients were the controls.

RESULTS

A total of 28.4%, 28.0%, 9% and 20.9% of PSC patients were positive for AAA IgA, AAA IgG, AGA IgA and AGA IgG, respectively. Frequencies of AAA IgA and AAA IgG (P < 0.001, for both) and AGA IgG (P = 0.01, for both) but not AGA IgA were significantly higher compared to both of the HCONT and the UC groups. In survival analysis, AAA IgA-positivity was revealed as an independent predictor of poor disease outcome after adjusting either for the presence of cirrhosis [HR = 5.15 (1.27-20.86), P = 0.022 or for the Mayo risk score (HR = 4.24 (0.99-18.21), P = 0.052]. AAA IgA-positivity was significantly associated with higher frequency of anti-microbial antibodies (P < 0.001 for EndoCab IgA and P = 0.012 for anti-OMP Plus IgA) and higher level of the enterocyte damage marker (median I-FABP_{AAA IgA posvsneg}: 365 vs 166 pg/mL, P = 0.011), but not with serum LBP level.

CONCLUSION

Presence of IgA type AAA identified PSC patients with progressive disease. Moreover, it is associated with enhanced mucosal immune response to various microbial antigens and enterocyte damage further highlighting the importance of the gut-liver interaction in PSC.

Association between serum soluble CD14 and IL-8 levels and clinical outcome in primary biliary cholangitis

BACKGROUND & AIMS

Primary biliary cholangitis (PBC) is an autoimmune liver disease characterized by portal inflammation and immune-mediated destruction of intrahepatic bile ducts that often leads to liver decompensation and liver failure. Although the biochemical response to ursodeoxycholic acid (UDCA) can predict disease outcome in PBC, few biomarkers have been identified as prognostic tools applicable prior to UDCA treatment. We therefore sought to identify such indicators of long-term outcome in PBC in the Japanese population.

METHODS

The prebiopsy serum samples and subsequent clinical data of 136 patients with PBC treated with UDCA were analysed over a median follow-up period of 8.8 years. Serum levels of biomarkers related to microbial translocation (sCD14, EndoCAb and I-FABP) were measured along with those of 33 cytokines and chemokines and additional auto-antibodies. Associations between the tested parameters and the clinical outcomes of liver decompensation and liver-related death/liver transplantation were evaluated using the Cox proportional hazards model with stepwise methods and Kaplan-Meier analysis.

RESULTS

Elevated levels of serum IL-8, and sCD14 before UDCA therapy were significantly associated with both liver decompensation and liver-related death/liver transplantation. In multivariate analyses, IL-8≥46.5 pg/mL or sCD14≥2.0 μg/mL at enrolment demonstrated the same results. Kaplan-Meier analysis also revealed IL-8 and sCD14 to be significantly associated with a poor outcome. sCD14 was significantly correlated with IL-8. EndoCAb and I-FABP were not related to disease outcome.

CONCLUSIONS

Serum IL-8 and sCD14 levels before UDCA therapy represent noninvasive surrogate markers of prognosis in patients with PBC.

Autoantibodies to domain 1 of beta 2 glycoprotein I determined using a novel chemiluminescence immunoassay demonstrate association with thrombosis in patients with antiphospholipid syndrome

INTRODUCTION

Antibodies to the domain 1 of beta 2 glycoprotein I (β2GPI-D1) have been suggested as a risk marker for thrombosis in patients with the antiphospholipid syndrome (APS). This cross-sectional study aimed to analyze the clinical utility of a novel chemiluminescence assay for the detection of anti-β2GPI-D1 antibodies.

PATIENTS AND METHODS

Sera collected from patients with primary or secondary APS (n = 106; 72 with and 34 without history of thrombosis) and controls (n = 272) were tested for anti-β2GPI-D1 IgG by chemiluminescence assay (QUANTA Flash) and by two anti-β2GPI IgG assays (QUANTA Lite and QUANTA Flash β2GPI IgG).

RESULTS

Anti-β2GPI-D1 IgG titers were significantly higher in patients with thrombosis (P = 0.0032) than those without. At the cut-off of 20 units, which yielded a 99.5% specificity, 24 of 72 (34.9%) patients with thrombosis and four of 34 (11.8%) without thrombosis were anti-β2GPI-D1 IgG positive (odds ratio, OR = 4.0). By further optimizing the cut-off specifically for correlation with thrombosis, 20.8% of the patients with thrombosis and 2.9% of the patients without thrombosis were positive (OR = 8.7). The ORs were significantly lower for antibodies to the full-length β2GPI by either the chemiluminescence assay or ELISA. Using the anti-β2GPI chemiluminescence assay, the OR was 2.3 (recommended cut-off of 20 CU) or 4.1 (optimal cut-off 164.6 CU). Using the anti-β2GPI ELISA, the OR was 2.7 (recommended cut-off of 20 units) or 3.7 (optimal cut-off 7.6 units).

CONCLUSION

These data indicate that anti-β2GPI-D1 IgG are present more frequently and in higher titers in APS patients with thrombotic complications than in those without.The novel β2GPI-D1 chemiluminescence assay appears to be superior to full-length β2GPI assays for the risk assessment of thrombotic events in APS patients.

COMP serum levels: A new non-invasive biomarker of liver fibrosis in patients with chronic viral hepatitis

BACKGROUND & AIMS

Recently we have shown that cartilage oligomeric matrix protein (COMP), a fibrillar collagen assembly regulator, is strongly associated with cirrhosis and hepatocellular carcinoma progression. Therefore, we assessed whether serum COMP levels can be used as a non-invasive fibrosis marker in patients with chronic viral hepatitis (CVH) and compared this marker with standard methods for disease stage assessment [histology, transient elastography (TE), APRI, FIB-4].

METHODS

Sera from 116 CVH patients, 66 HBV [24 female; median age 53(22-76)] and 50 HCV [21 female; median age 48.5(25-69)] were investigated by COMP-ELISA. APRI and FIB-4 score was calculated in all along with TE. Liver biopsy was performed in 61. Patients were divided into two groups (F1/F2 and F3/F4) according to Metavir score.

RESULTS

55/116 (47%) CVH patients were classified in F3/F4-group according to TE [14.3(9.3-75)kPa]. APRI score was >1.5 in 21/116 and FIB-4>3.25 in 20/116. Liver histology revealed 24/61 (39%) patients with significant fibrosis (stage 3-4), while 12/61 (19.7%) had cirrhosis. COMP levels correlated with TE measurements (r=0.5; p<0.001) and APRI score (r=0.23; p<0.02). The diagnostic accuracy of COMP in detecting cirrhosis was as good as TE, APRI and FIB-4 index (AUC 0.884) with sensitivity and specificity of 83.3% and 83.7% (cut-off 11.5U/L).

CONCLUSIONS

COMP serum levels performed as well as TE, APRI and FIB4 score in detecting cirrhosis in CVH patients, suggesting COMP as a sensitive non-invasive, easy to perform biomarker of liver fibrosis. Further studies are needed in order to validate our findings in CVH patients.

Autoantibodies to the Atheroma Component Beta2-Glycoprotein I and Risk of Symptomatic Peripheral Artery Disease

Peripheral artery disease (PAD) is mostly related to atherosclerosis. Autoimmunity and, in particular, antibodies to cardiolipin (aCL) and phospholipid cofactors such as beta2-glycoprotein I (beta2-gpI) might influence the development of atheroma. Beta2-glycoprotein I (beta2-gpI) has been found in atheroma. It has previously been shown that immunoglobulin A (IgA) anti-beta2-gpI antibodies are associated with a risk of cerebral ischemia and myocardial infarction. This case control study aimed to determine whether elevated levels of aCL/anti-beta2-gpI antibodies are associated with a risk of symptomatic PAD (sPAD). Cases comprised a nonselected population of patients with sPAD (intermittent claudication or critical ischemia). Patient recruitment was based on arteriography changes. Controls were selected from patients admitted to orthopedic wards as a result of fractures or muscle-ligamentous disorders. Age, sex, race, hypertension, smoking, diabetes mellitus, and hypercholesterolemia were evaluated as risk factors in both groups. IgG/IgM/IgA aCL and anti-beta2-gpI were detected by enzyme-linked immunoabsorbant assays (ELISA). To estimate the grade of association of antibodies with sPAD, odds ratios (OR) were calculated. Logistic regression was utilized for adjustment of confounding factors. Seventy-seven cases and 93 controls were studied. The mean age was 61.5 years for cases and 47.5 years for controls (p <0.001). Among the risk factors evaluated, the presence of hypertension showed the strongest association with sPAD (OR 12.1; 95%CI 5.8—30). The presence of IgA anti-beta2-gpI was independently associated with sPAD (OR 5.4; 95%CI 1.8—15.8; p = 0.01). IgA aCL was strongly associated with the outcome (nonadjusted OR 11.5 after Agresti correction). IgA aCL and IgA anti-beta2-gpI antibodies were not associated with any known risk factors for sPAD or with arteriography changes. The occurrence of these autoantibodies might represent one of the links between autoimmunity and atherosclerosis in patients with sPAD.

Assessment of health related quality of life in polish patients with primary biliary cirrhosis

BACKGROUND

Most patients with primary biliary cirrhosis (PBC) have impaired health related quality of life (HRQoL), as assessed by PBC-specific HRQoL (PBC-40) and generic (SF-36) questionnaires. Data on the applicability of PBC-27, a shorter version of PBC-40, have been limited.

AIMS

To assess HRQoL in Polish PBC patients, applying PBC-40, PBC-27 and SF-36 and to associate clinical or laboratory parameters with HRQoL factors.

METHODS

A total of 205 PBC patients (188 females) were analyzed using PBC-40, PBC-27 and SF-36; 85 disease-free demographically matched (in terms of age, gender, ethnicity) individuals were used as normal controls.

RESULTS

When compared to controls, PBC patients had significantly impaired HRQoL across all the domains of SF-36. HRQoL impairment by PBC-40 and PBC-27 was comparable between cirrhotics and non-cirrhotics, except for significantly worse Itch in cirrhotics (6.5±4.9 vs 5.1±4.3; P=0.03). In PBC-40/27, alkaline phosphatase (ALP) levels correlated with itch (P=0.0003). Female patients had marginally impaired cognitive function compared to males by PBC-40 (P=0.06). Other gender-related differences were not found. Anti-gp210 positive, as well as AMA negative PBC patients, had worse HRQoL features in itch and social/emotional domains of PBC-40/PBC-27 questionnaires. Very strong correlations (P<0.0001) between PBC-40/PBC-27 and SF-36 were seen for several domains.

CONCLUSIONS

HRQoL is significantly impaired in Polish patients with PBC, independently of gender and disease severity. PBC-40 and PBC-27 questionnaires are efficient in detecting HRQoL impairment in Polish PBC patients. The striking correlation between PBC-40/PBC-27 and SF-36 confirms the usefulness of the former HRQoL measures in PBC patients from Central-Eastern Europe.

Evaluation of phosphatidylserine-dependent antiprothrombin antibody testing for the diagnosis of antiphospholipid syndrome: results of an international multicentre study

Objective A task force of scientists at the International Congress on Antiphospholipid Antibodies recognized that phosphatidylserine-dependent antiprothrombin antibodies (aPS/PT) might contribute to a better identification of antiphospholipid syndrome (APS). Accordingly, initial and replication retrospective, cross-sectional multicentre studies were conducted to ascertain the value of aPS/PT for APS diagnosis. Methods In the initial study (eight centres, seven countries), clinical/laboratory data were retrospectively collected. Serum/plasma samples were tested for IgG aPS/PT at Inova Diagnostics (Inova) using two ELISA kits. A replication study (five centres, five countries) was carried out afterwards. Results In the initial study ( n = 247), a moderate agreement between the IgG aPS/PT Inova and MBL ELISA kits was observed ( k = 0.598). IgG aPS/PT were more prevalent in APS patients (51%) than in those without (9%), OR 10.8, 95% CI (4.0-29.3), p < 0.0001. Sensitivity, specificity, positive (LR+) and negative (LR-) likelihood ratio of IgG aPS/PT for APS diagnosis were 51%, 91%, 5.9 and 0.5, respectively. In the replication study ( n = 214), a moderate/substantial agreement between the IgG aPS/PT results obtained with both ELISA kits was observed ( k = 0.630). IgG aPS/PT were more prevalent in APS patients (47%) than in those without (12%), OR 6.4, 95% CI (2.6-16), p < 0.0001. Sensitivity, specificity, LR + and LR- for APS diagnosis were 47%, 88%, 3.9 and 0.6, respectively. Conclusions IgG aPS/PT detection is an easily performed laboratory parameter that might contribute to a better and more complete identification of patients with APS.

Significance of fully automated tests for the diagnosis of antiphospholipid syndrome

Antiphospholipid antibodies (aPLs) can vary both immunologically and functionally, thus it is important to effectively and correctly identify their presence when diagnosing antiphospholipid syndrome. Furthermore, since many immunological/functional tests are necessary to measure aPLs, complete examinations are often not performed in many cases due to significant burden on the testing departments. To address this issue, we measured aPLs defined according to the classification criteria (anticardiolipin antibody: aCL) IgG/IgM and anti-β₂ glycoprotein I antibody (aβ₂GPI) (IgG/IgM) as well as non-criteria antibodies (aCL IgA, aβ₂GPI IgA and aβ₂GPI domain I), in a cohort of 211 patients (61 APS, 140 disease controls and 10 healthy individuals). APLs were measured using a fully automated chemiluminescent immunoassay instrument (BIO-FLASH®/ACL AcuStar®) and with conventional ELISA tests. We demonstrated that both sensitivity and accuracy of diagnosis of aCL IgG and aβ₂GPI IgG were high, in agreement with the past reports. When multiple aPLs were examined, the accuracy of diagnosis increased. The proportion of APS patients that were positive for 2 or more types of aPLs (47/61, 77%) was higher than that of patients with systemic lupus erythematosus (SLE)(3/37, 9%), those with non-SLE connective tissues diseases (1/53,2%), those with other diseases or healthy volunteers. Based on these findings, it was concluded that the fully automated chemiluminescent immunoassay instrument, which allows the simultaneous evaluation of many types of aPLs, offers clear advantages for a more complete, more rapid and less labor-intensive alternative to running multiple ELISA and could help in better diagnosis for suspected APS patients.

Clinical characterization of antiphospholipid syndrome by detection of IgG antibodies against β2 -glycoprotein i domain 1 and domain 4/5: ratio of anti-domain 1 to anti-domain 4/5 as a useful new biomarker for antiphospholipid syndrome

OBJECTIVE

It has been suggested that only antibodies against domain 1 (D1) of β2 -glycoprotein I (β2 GPI) are pathogenic and diagnostic. The role of antibodies against other β2 GPI domains is still debated. This study was undertaken to evaluate the clinical relevance of domain specificity profiling of anti-β2 GPI IgG antibodies in antiphospholipid syndrome (APS) patients and in control groups of patients with systemic autoimmune rheumatic diseases and in asymptomatic antiphospholipid antibody (aPL) carriers.

METHODS

We evaluated 159 subjects with persistently positive, medium or high-titer anti-β2 GPI IgG, including 56 patients with thrombotic (obstetric or nonobstetric) primary APS, 31 women with obstetric primary APS, 42 aPL-positive patients with systemic autoimmune rheumatic diseases, and 30 asymptomatic aPL carriers. One hundred healthy donors were included. Anti-β2 GPI D1 and D4/5 IgG were tested on research enzyme-linked immunosorbent assays containing recombinant β2 GPI domains.

RESULTS

As compared to other groups, aPL carriers displayed higher frequency/titer of anti-D4/5 IgG. Unlike anti-D4/5, anti-D1 IgG antibodies were more frequent and at higher titer in triple than in single or double aPL-positive subjects. An anti-D1 to anti-D4/5 ratio of ≥1.5 was predictive of systemic autoimmunity (odds ratio 3.25 [95% confidence interval 1.45-7.49], P = 0.005). Neither anti-D1 nor anti-D4/5 antibodies were associated with APS clinical criteria.

CONCLUSION

Anti-D1 IgG is the preferential specificity not only in vascular and obstetric primary APS, but also in patients with systemic autoimmune rheumatic disease with no clinical features of APS. Conversely, aPL carriers do not have a polarized profile toward D1. Combined testing for anti-β2 GPI IgG with different domain specificity allows a more accurate aPL profiling, with polarization toward anti-D1 IgG as a possible fingerprint of systemic autoimmunity.

The Significance of Autoantibody Changes Over Time in Primary Biliary Cirrhosis

OBJECTIVES

In primary biliary cirrhosis (PBC), the antimitochondrial antibody is a cornerstone of diagnosis, but there have been conflicting reports about the correlation of autoantibodies with disease stage and prognosis. We studied whether autoantibody levels changed over time and sought correlations with clinical outcomes in a cohort of patients with PBC.

METHODS

We tested serial serum samples from patients with PBC at a research institution for several autoantibodies. Long-term clinical follow-up data were used to calculate the slopes (change over time) for autoantibodies, platelet count, Ishak fibrosis score, biopsy copper, and number of portal areas with bile ducts. An adverse clinical outcome was defined as hepatic decompensation, development of hepatocellular carcinoma, liver transplantation, or liver-related death. We performed linear or logistic regression or Fisher exact test as appropriate, adjusting for multiple comparisons.

RESULTS

Twenty-seven patients with PBC with 145 serum samples were studied. Of the cohort, 85% was white, 81% was female, and median follow-up time was 20 years. Of the autoantibodies tested, only sp100 changed significantly over time. The sp100 slope was inversely associated with the Ishak fibrosis slope (parameter estimate, -0.05; P = .0003).

CONCLUSIONS

While changes in most autoantibodies over time do not seem to correlate with clinical outcomes in PBC, a change in the sp100 autoantibody level may have prognostic utility with respect to the development of fibrosis on liver biopsy.

Risk Matrix for Prediction of Disease Progression in a Referral Cohort of Patients with Crohn's Disease

BACKGROUND

Early identification of patients with Crohn's disease (CD) at risk of subsequent complications is essential for adapting the treatment strategy. We aimed to develop a prediction model including clinical and serological markers for assessing the probability of developing advanced disease in a prospective referral CD cohort.

METHODS

Two hundred and seventy-one consecutive CD patients (42.4% males, median follow-up 108 months) were included and followed up prospectively. Anti-Saccharomyces cerevisiae antibodies (ASCA IgA/IgG) were determined by enzyme-linked immunosorbent assay. The final analysis was limited to patients with inflammatory disease behaviour at diagnosis. The final definition of advanced disease outcome was having intestinal resection or disease behaviour progression.

RESULTS

Antibody (ASCA IgA and/or IgG) status, disease location and need for early azathioprine were included in a 3-, 5- and 7-year prediction matrix. The probability of advanced disease after 5 years varied from 6.2 to 55% depending on the combination of predictors. Similar findings were obtained in Kaplan-Meier analysis; the combination of ASCA, location and early use of azathioprine was associated with the probability of developing advanced disease (p < 0.001, log rank test).

CONCLUSIONS

Our prediction models identified substantial differences in the probability of developing advanced disease in the early disease course of CD. Markers identified in this referral cohort were different from those previously published in a population-based cohort, suggesting that different prediction models should be used in the referral setting.

Rediscovery of the Anti-Pancreatic Antibodies and Evaluation of their Prognostic Value in a Prospective Clinical Cohort of Crohn's Patients: The Importance of Specific Target Antigens [GP2 and CUZD1]

BACKGROUNDS

Glycoprotein 2[GP2] and CUB zona pellucida-like domain 1[CUZD1] belong to protein families involved in gut innate immunity processes and have recently been identified as specific targets of anti-pancreatic autoantibodies [PAbs] in Crohn's disease[CD]. We aimed to determine the prognostic potential of novel target-specific PAbs regarding long-term disease course of an adult CD patient cohort.

METHODS

Sera of 458 consecutive well-characterised IBD patients from a single referral IBD centre were tested by enzyme-linked immunosorbent assay [ELISA] with isoform 4 of recombinant GP2 [anti-MZGP2 and anti-GP2 IgA/IgG] and indirect immunofluorescence test [IIFT] system with GP2 and CUZD1 expressing transfected HEK 293 cells [anti-rPAg2 and rPAg1 IgA/IgG]. Clinical data were available on complicated disease or surgical interventions as well as disease activity and medical treatment during the prospective follow-up [median, 108 months].

RESULTS

Totals of 12.4% and 20.8% of CD patients were positive for IgA/IgG type of anti-GP2 and anti-CUZD1, respectively, with a significant difference compared with UC [p < 0.01]. Antibody status was stable over time. Agreement among three different anti-GP2 assays was good. Positivity for PAbs, mainly IgA subtypes, predicted a faster progression towards complicated disease course. In Kaplan-Meier analysis, time to surgery or development of perianal disease was associated with anti-GP2 IgA [pLogRank < 0.01] or anti-CUZD1 IgA [pLogRank < 0.001] positivity, respectively. Anti-CUZD1 IgA remained an independent predictor in the multivariate Cox-regression model (hazard ratio [HR]: 3.43, 95% confidence interval [CI]: 1.68-7.02, p < 0.001).

CONCLUSIONS

The present study has shown that specific PAbs [especially IgA subtype] predict complicated disease course including the development of perianal disease in CD.

Cartilage oligomeric matrix protein: A novel non-invasive marker for assessing cirrhosis and risk of hepatocellular carcinoma

AIM

To assess serum cartilage oligomeric matrix protein (COMP) as a marker of cirrhosis and risk of progression to hepatocellular carcinoma (HCC).

METHODS

A COMP enzyme-linked immunosorbent assay was used to test 187 patients with chronic liver diseases at the time point of first evaluation. The selected patients included 72 with chronic hepatitis B infection, 75 with chronic hepatitis C infection, 22 with primary biliary cirrhosis, 7 with autoimmune hepatitis type 1, and 11 with alcoholic liver disease. Demographic, biochemical, histological and clinical characteristics of the patients were recorded at the first evaluation. One hundred and forty-seven patients were followed for a median [interquartile range (IQR)] duration of 96.5 (102) mo. The clinical, biochemical and histological data, as well as the development of cirrhosis, HCC according to internationally accepted criteria and in case of death, a liver-related cause during the follow-up period, were recorded at the electronic database of our clinic. COMP determination was also performed in 43 healthy individuals who served as the control study group.

RESULTS

COMP positivity (> 15 U/L) was detected in 22%-36% among chronic liver disease groups. Strikingly, almost 83% of COMP-positive patients were cirrhotic at baseline, independently of cause of liver disease. Among the patients who developed HCC during follow-up, 73.7% (14/19) were COMP positive at baseline. COMP positivity was significantly associated with older age (P < 0.001), advanced fibrosis (P = 0.001) and necroinflammatory activity (P = 0.001), higher aspartate aminotransferase (P < 0.001), alanine aminotransferase (P < 0.02), γ-glutamyl transpeptidase (P = 0.003), alkaline phosphatase (P = 0.001), bilirubin (P < 0.05), international normalized ratio (P = 0.002) and alpha-fetoprotein levels (P < 0.02), and lower albumin (P < 0.001), and platelet count (P = 0.008). COMP levels [median (IQR)] were significantly higher in cirrhotics compared to non-cirrhotics [13.8 (7.9) U/L vs 9.8 (4.6) U/L, respectively; P < 0.001]. On multivariate logistic regression analysis, COMP-positivity was independently associated only with cirrhosis (OR = 4.40, 95%CI: 1.33-14.69, P = 0.015). Kaplan-Meier analysis showed that COMP positivity was significantly associated with HCC development (P = 0.007) and higher incidence of liver-related death (P < 0.001).

CONCLUSION

Elevated COMP levels are strongly associated with cirrhosis and HCC progression. Serum COMP is a new promising non-invasive biomarker for HCC risk assessment in surveillance programs.

Validity of the global anti-phospholipid syndrome score to predict thrombosis: a prospective multicentre cohort study

OBJECTIVE

To investigate the validity of the global APS score (GAPSS) to predict thrombosis in patients with autoimmune diseases.

METHODS

This prospective cohort study included consecutive patients with aPL or SLE. aPL, aPS-PT and GAPSS were determined. A Cox proportional hazards model assessed the validity of GAPSS and identified other potential independent predictors of thrombosis.

RESULTS

One hundred and thirty-seven patients [43.5 (s.d. 15.4) years old; 107 women] were followed up for a mean duration of 43.1 (s.d. 20.7) months. Mean GAPSS was significantly higher in patients who experienced a thrombotic event compared with those without [10.88 (s.d. 5.06) vs 8.15 (s.d. 5.31), respectively, P = 0.038]. In univariate analysis, age [hazard ratio (HR) = 1.04 (95% CI 1.01, 1.08)] and GAPSS above 16 [HR = 6.86 (95% CI 1.90, 24.77)] were each significantly associated with thrombosis during follow-up, while history of arterial thrombosis [HR = 2.61 (95% CI 0.87, 7.82)] failed to reach significance. Among aPL assays, IgG aPS/PT--a component of the GAPSS--was significantly associated with thrombosis [HR = 2.95 (95% CI 1.02, 8.51)]. In multivariate analysis, GAPSS above 16 remained the only significant predictor of thrombosis [HR = 6.17 (95% CI 1.70, 22.40)].

CONCLUSION

This first external validation study confirmed that GAPSS can predict thrombosis in patients with aPL and associated autoimmune diseases.

Prevalence, significance and predictive value of antiphospholipid antibodies in Crohn’s disease

AIM: To assess the prevalence and stability of different antiphospholipid antibodies (APLAs) and their association with disease phenotype and progression in inflammatory bowel diseases (IBD) patients.

METHODS: About 458 consecutive patients [Crohn’s disease (CD): 271 and ulcerative colitis (UC): 187] were enrolled into a follow-up cohort study in a tertiary IBD referral center in Hungary. Detailed clinical phenotypes were determined at enrollment by reviewing the patients’ medical charts. Disease activity, medical treatment and data about evolvement of complications or surgical interventions were determined prospectively during the follow-up. Disease course (development f complicated disease phenotype and need for surgery), occurrence of thrombotic events, actual state of disease activity according to clinical, laboratory and endoscopic scores and accurate treatment regime were recorded during the follow-up, (median, 57.4 and 61.6 mo for CD and UC). Sera of IBD patients and 103 healthy controls (HC) were tested on individual anti-β2-Glycoprotein-I (anti-β2-GPI IgA/M/G), anti-cardiolipin (ACA IgA/M/G) and anti-phosphatidylserine/prothrombin (anti-PS/PT IgA/M/G) antibodies and also anti-Saccharomyces cerevisiae antibodies (ASCA IgA/G) by enzyme-linked immunosorbent assay (ELISA). In a subgroup of CD (n = 198) and UC patients (n = 103), obtaining consecutive samples over various arbitrary time-points during the disease course, we evaluated the intraindividual stability of the APLA status. Additionally, we provide an overview of studies, performed so far, in which significance of APLAs in IBD were assessed.

RESULTS: Patients with CD had significantly higher prevalence of both ACA (23.4%) and anti-PS/PT (20.4%) antibodies than UC (4.8%, P < 0.0001 and 10.2%, P = 0.004) and HC (2.9%, P < 0.0001 and 15.5%, P = NS). No difference was found for the prevalence of anti-β2-GPI between different groups (7.2%-9.7%). In CD, no association was found between APLA and ASCA status of the patients. Occurrence of anti-β2-GPI, ACA and anti-PS/PT was not different between the group of patients with active vs inactive disease state according to appropriate clinical, laboratory and endoscopic scores in CD as well as in UC patients. All subtypes of anti-β2-GPI and ACA IgM status were found to be very stable over time, in contrast ACA IgG and even more ACA IgA status showed significant intraindividual changes. Changes in antibody status were more remarkable in CD than UC (ACA IgA: 49.9% vs 23.3% and ACA IgG: 21.2% vs 5.8%). Interestingly, 59.1% and 30.1% of CD patients who received anti-TNF therapy showed significant negative to positive changes in ACA IgA and IgG antibody status respectively. APLA status was not associated with the clinical phenotype at diagnosis or during follow-up, medical therapy, or thrombotic events and it was not associated with the probability of developing complicated disease phenotype or surgery in a Kaplan-Meier analysis.

CONCLUSION: The present study demonstrated enhanced formation of APLAs in CD patients. However, presence of different APLAs were not associated with the clinical phenotype or disease course.