Concurrence of Guillain-Barré syndrome and primary biliary cholangitis not related to SARS-CoV-2: Case report. / Concurrencia de síndrome de Guillain-Barré y colangitis biliar primaria no vinculado a SARS-CoV-2: reporte de caso.

Introduction: Guillain-Barré syndrome is a polyradiculoneuropathy of autoimmune origin, considered the most frequent cause of acute flaccid paralysis. Various associations of Guillain-Barré syndrome with other non-neurological autoimmune diseases have been reported, some of them extremely rare, such as that which occurs with primary biliary cholangitis, a chronic disease of autoimmune etiology whose diagnosis is also supported by the clinical picture. , in the alteration of liver enzymes and the presence of anti-mitochondrial antibodies. Clinical case: A 38-year-old male patient, with no history of previous comorbidities, who, after presenting with diarrheal disease two weeks prior, developed subacute onset ascending weakness associated with paresthesias in four extremities that progressed to quadriplegia and respiratory distress. Cerebrospinal fluid cytochemistry was performed, which showed albuminocytological dissociation and electromyography, which showed findings compatible with acute motor axonal neuropathy, for which he received treatment with intravenous immunoglobulin at 0.4g/kg/day, achieving improvement in the neurological condition. Since admission and during hospitalization, he presented persistent changes in liver enzymes which followed a cholestatic pattern, in addition to mild abdominal pain and generalized itching, for which he was evaluated by gastroenterology, who requested anti-mitochondrial antibodies that were positive. Concluding in the diagnosis of primary biliary cholangitis. Conclusion: The present case shows an extremely rare association of two autoimmune diseases Guillain-Barré syndrome and primary biliary cholangitis, so much so that it represents the first case reported, not linked to SARS-CoV-2.

Introducción: El síndrome de Guillain-Barré es una polirradiculoneuropatia de origen autoinmune, considerada la causa más frecuente de parálisis flácida aguda. Se han reportado diversas asociaciones del síndrome de Guillain-Barré con otras enfermedades autoinmunes no neurológicas, algunas de ellas extremadamente raras, como la que ocurre con la colangitis biliar primaria, una enfermedad crónica de etiología autoinmune cuyo diagnóstico se sustenta, además del cuadro clínico, en la alteración de las enzimas hepáticas y la presencia de anticuerpos anti-mitocondriales. Caso clínico: Paciente varón de 38 años, sin antecedente de comorbilidades previas, quien luego de presentar enfermedad diarreica dos semanas antes, desarrolló debilidad ascendente de inicio subagudo asociado a parestesias en cuatro extremidades que progresó hasta generar cuadriplejia y dificultad respiratoria. Se le realizó examen citoquímico de líquido cefalorraquídeo que evidenció disociación albumino-citológica y electromiografía que mostró hallazgos compatibles con neuropatía axonal motora aguda. Recibió tratamiento con inmunoglobulina intravenosa a dosis de 0,4 gramos por kilogramo al día, logrando mejoría del cuadro neurológico. Desde su ingreso y durante la hospitalización, presentó alteración persistente de las enzimas hepáticas que seguía un patrón colestásico. Además, se agregó dolor abdominal de leve intensidad y prurito generalizado, por lo cual fue evaluado por gastroenterología, quienes solicitaron anticuerpos anti-mitocondriales que resultaron positivos. Con esta prueba, se comprobó el diagnóstico de colangitis biliar primaria. Conclusión: El presente caso muestra una asociación extremadamente rara de dos enfermedades autoinmunes; síndrome de Guillain-Barré y colangitis biliar primaria, tanto así que representa el primer caso reportado, no vinculado a SARS-CoV-2.

Autoimmune Hepatitis-Primary Biliary Cholangitis Overlap Syndrome Triggered by COVID-19.

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 infection, has caused the ongoing global pandemic. Initially considered a respiratory disease, it can manifest with a wide range of complications (gastrointestinal, neurological, thromboembolic and cardiovascular) leading to multiple organ dysfunction. A range of immune complications have also been described. We report the case of a 57-year-old man with a medical history of hypertension, prediabetes and beta thalassemia minor, who was diagnosed with COVID-19 and subsequently developed fatigue and arthralgias, and whose blood work showed hyperferritinemia, elevated liver enzymes (AST/ALT/GGT), hypergammaglobulinemia, anti-smooth muscle antibody, anti-mitochondrial antibody, and anti-double-stranded DNA antibodies. The patient was diagnosed with autoimmune hepatitis-primary biliary cholangitis overlap syndrome triggered by COVID-19. To our knowledge, this is the first such case reported. LEARNING POINTS: COVID-19 can precipitate a wide range of immune complications; we report a case of autoimmune hepatitis-primary biliary cholangitis overlap syndrome triggered by COVID-19.Clinicians should be aware of this unusual manifestation of COVID-19 so that prompt and appropriate diagnostic and therapeutic interventions can be initiated if the syndrome is suspected or confirmed.Our case further suggests the necessity for continued and regular follow-up of patients who have recovered from COVID-19 in order to uncover the long-term effects of the novel virus.

The Genetics of Primary Biliary Cholangitis: A GWAS and Post-GWAS Update.

Primary biliary cholangitis (PBC) is a chronic, progressive cholestatic liver disease in which the small intrahepatic bile ducts are destroyed by autoimmune reactions. Among autoimmune diseases, which are polygenic complex traits caused by the combined contribution of genetic and environmental factors, PBC exhibits the strongest involvement of genetic heritability in disease development. As at December 2022, genome-wide association studies (GWASs) and associated meta-analyses identified approximately 70 PBC susceptibility gene loci in various populations, including those of European and East Asian descent. However, the molecular mechanisms through which these susceptibility loci affect the pathogenesis of PBC are not fully understood. This study provides an overview of current data regarding the genetic factors of PBC as well as post-GWAS approaches to identifying primary functional variants and effector genes in disease-susceptibility loci. Possible mechanisms of these genetic factors in the development of PBC are also discussed, focusing on four major disease pathways identified by in silico gene set analyses, namely, (1) antigen presentation by human leukocyte antigens, (2) interleukin-12-related pathways, (3) cellular responses to tumor necrosis factor, and (4) B cell activation, maturation, and differentiation pathways.

Ursodeoxycholic acid is associated with a reduction in SARS-CoV-2 infection and reduced severity of COVID-19 in patients with cirrhosis.

BACKGROUND AND AIMS: Studies have demonstrated that reducing farnesoid X receptor activity with ursodeoxycholic acid (UDCA) downregulates angiotensin-converting enzyme in human lung, intestinal and cholangiocytes organoids in vitro, in human lungs and livers perfused ex situ, reducing internalization of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) into the host cell. This offers a potential novel target against coronavirus disease 2019 (COVID-19). The objective of our study was to compare the association between UDCA exposure and SARS-CoV-2 infection, as well as varying severities of COVID-19, in a large national cohort of participants with cirrhosis. METHODS: In this retrospective cohort study among participants with cirrhosis in the Veterans Outcomes and Costs Associated with Liver cohort, we compared participants with exposure to UDCA, with a propensity score (PS) matched group of participants without UDCA exposure, matched for clinical characteristics, and vaccination status. The outcomes included SARS-CoV-2 infection, symptomatic, at least moderate, severe, or critical COVID-19, and COVID-19-related death. RESULTS: We compared 1607 participants with cirrhosis who were on UDCA, with 1607 PS-matched controls. On multivariable logistic regression, UDCA exposure was associated with reduced odds of developing SARS-CoV-2 infection (adjusted odds ratio [aOR] 0.54, 95% confidence interval [CI] 0.41-0.71, p < 0.0001). Among patients who developed COVID-19, UDCA use was associated with reduced disease severity, including symptomatic COVID-19 (aOR 0.54, 95% CI 0.39-0.73, p < 0.0001), at least moderate COVID-19 (aOR 0.51, 95% CI 0.32-0.81, p = 0.005), and severe or critical COVID-19 (aOR 0.48, 95% CI 0.25-0.94, p = 0.03). CONCLUSIONS: In participants with cirrhosis, UDCA exposure was associated with both a decrease in SARS-CoV-2 infection, and reduction in symptomatic, at least moderate, and severe/critical COVID-19.

Genetic predisposition between coronavirus disease 2019 and rheumatic diseases: A 2-sample Mendelian randomization study.

OBJECTIVE: The causalities between the coronavirus disease 2019 (COVID-19) and the risk of rheumatic diseases remain unclear. The purpose of this study was to investigate the causal effect of COVID-19 on rheumatic disease occurrence. METHODS: Single nucleotide polymorphisms (SNPs), acquired from published genome-wide association studies, were used to perform 2-sample Mendelian randomization (MR) on cases diagnosed with COVID-19 (n = 13 464), rheumatic diseases (n = 444 199), juvenile idiopathic arthritis (JIA, n = 15 872), gout (n = 69  374), systemic lupus erythematosus (SLE, n = 3094), ankylosing spondylitis (n = 75 130), primary biliary cholangitis (PBC, n = 11 375) and primary Sjögren's syndrome (n = 95 046). Three MR methods were used in the analysis based on different heterogeneity and pleiotropy using the Bonferroni correction. RESULTS: The results revealed a causality between COVID-19 and rheumatic diseases with an odds ratio (OR) of 1.010 (95% confidence interval [CI], 1.006-1.013; P = .014). In addition, we observed that COVID-19 was causally associated with an increased risk of JIA (OR 1.517; 95%CI, 1.144-2.011; P = .004), PBC (OR 1.370; 95%CI, 1.149-1.635; P = .005), but a decreased risk of SLE (OR 0.732; 95%CI, 0.590-0.908; P = .004). Using MR, 8 SNPs were identified to associate with COVID-19 and recognized as significant variables. None of them were previously reported in any other diseases. CONCLUSIONS: This is the first study to use MR to explore the impact of COVID-19 on rheumatic diseases. From a genetic perspective, we found that COVID-19 could increase the risk of rheumatic diseases, such as PBC and JIA, but decrease that of SLE, thereby suggesting a potential surge in the disease burden of PBC and JIA following the COVID-19 pandemic.

Antimitochondrial Antibodies: from Bench to Bedside.

Anti-mitochondrial antibodies (AMA) are directed against the E2 subunits of the 2-oxo acid dehydrogenase complexes (PDC-E2) and are the typical biomarkers of primary biliary cholangitis (PBC), being present in 90-95% of patients, with increasing sensitivity at increasing titers. Albeit being highly specific for PBC diagnosis, AMA can be detected in less than 1% of healthy subjects, and thus the management subjects with no sign or symptom of liver disease is still a challenge and data concerning clinical risk of developing PBC in this subgroup of patients are controversial. Moreover, AMA can also be detected in patients affected by overlap syndrome, as well as hepatic diseases (i.e., NASH and viral hepatitis), while the association with autoimmune diseases, in particular Sjögren's syndrome, systemic sclerosis, and systemic lupus erythematosus, is well established. Furthermore, new associations are being identified with inflammatory myositis and heart disease. AMA are directed towards the pyruvate dehydrogenase multi enzyme complex (PDC-E2) subunit, which represents an epithelial specific autoantigen for PBC. This review focuses on the main characteristics of AMA, their association with autoimmune diseases and liver diseases.

COVID-19 in Patients with Primary Biliary Cholangitis

The aim of the study. To analyze the course of COVID-19 infection in patients with primary biliary cholangitis (PBC). Materials and methods. In a single-center retrospective study, survey and analysis of medical records of 144 patients with PBC was carried out. Results. All patients (n = 144) received basic therapy with ursodeoxycholic acid (UDCA), 5 of them received fibrates as well. Response to therapy (EASL criteria) was obtained in 30 people. Between March 2020 and March 2021, 50 patients (34.7 %) suffered COVID-19, with mean age of 58.8 ± 10.7 years, 16 of which were diagnosed with liver cirrhosis. Mild COVID-19 was observed in 34 (68 %) people, moderate course - in 14 (28 %), severe - in 2 (4 %), cases of extremely severe course were not recorded. 12 patients were hospitalized, 8 of which received oxygen therapy due to a decrease in SpO2 < 94 %, there was no need for the use of other methods of oxygen therapy in any case. The duration of hospitalization was 11.4 ± 5.7 days. There was a higher initial activity of serum alkaline phosphatase (1.8 ± 1.0 versus 1.7 ± 1.4 times of the upper limit of normal, M ± SD, p = 0.04) in patients with COVID-19 infection and lack of UDCA therapy effectiveness was more prominent (40 % vs. 19.1 % of cases, p = 0.04) compared with patients who did not have COVID-19. There were no significant differences in characteristics of the course of PBC (stage, response to therapy) and age in correlation with severity of the course of COVID-19. Among hospitalized patients and those in need of oxygen support, large proportion were older patients (58.3 % and 62.5 %, respectively) and patients with concomitant diseases (62.5 % and 75 %, respectively). Patients who hadn't previously responded to UDCA therapy were more likely to require oxygen support compared to patients responding to basic therapy (p < 0.01). Conclusion. PBC is not a risk factor for severe COVID-19. A protective effect of UDCA in SARS-CoV-2 infection is possible, which requires further investigation. © 2022 Russian Journal of Gastroenterology, Hepatology, Coloproctology

SARS-CoV-2 vaccination response in patients with autoimmune hepatitis and autoimmune cholestatic liver disease.

BACKGROUND/AIMS: In this observational study, we explored the humoral and cellular immune response to SARS-CoV-2 vaccination in patients with autoimmune hepatitis (AIH) and patients with cholestatic autoimmune liver disease (primary sclerosing cholangitis [PSC] and primary biliary cholangitis [PBC]). METHODS: Anti-SARS-CoV-2 antibody titers were determined using the DiaSorin LIAISON and Roche immunoassays in 103 AIH, 64 PSC, and 61 PBC patients and 95 healthy controls >14 days after the second COVID-19 vaccination. The spike-specific T-cell response was assessed using an activation-induced marker assay (AIM) in a subset of individuals. RESULTS: Previous SARS-CoV-2 infection was frequently detected in AIH but not in PBC/PSC (10/112 (9%), versus 4/144 (2.7%), p = 0.03). In the remaining patients, seroconversion was measurable in 97% of AIH and 99% of PBC/PSC patients, respectively. However, in 13/94 AIH patients antibody levels were lower than in any healthy control, which contributed to lower antibody levels of the total AIH cohort when compared to PBC/PSC or controls (641 vs. 1020 vs. 1200 BAU/ml, respectively). Notably, antibody levels were comparably low in AIH patients with (n = 85) and without immunosuppression (n = 9). Also, antibody titers significantly declined within 7 months after the second vaccination. In the AIM assay of 20 AIH patients, a spike-specific T-cell response was undetectable in 45% despite a positive serology, while 87% (13/15) of the PBC/PSC demonstrated a spike-specific T-cell response. CONCLUSION: Patients with AIH show an increased SARS-CoV-2 infection rate as well as an impaired B- and T-cell response to SARS-CoV-2 vaccine compared to PBC and PSC patients, even in the absence of immunosuppression. Thus, antibody responses to vaccination in AIH patients need to be monitored and early booster immunizations considered in low responders.

Promyelocytic Leukemia Antigen Expression: a Histological Marker for Primary Biliary Cholangitis Diagnosis?

BACKGROUND AND OBJECTIVES: Distinguishing primary biliary cholangitis (PBC) from other cholestatic diseases at the histological level could be assisted by new methods, such as immunohistochemical staining of specific antigens. METHODS: We evaluated whether the detection of promyelocytic leukemia protein (PML) can serve as a specific and sensitive marker for PBC diagnosis. Liver biopsies from 26 PBC patients, 20 primary sclerosing cholangitis (PSC), 37 viral hepatitis, 11 non-alcoholic steatohepatitis (NASH) and 5 normal patients were investigated after immunostaining with the anti-PML monoclonal PG-M3, IgG1 antibody. RESULTS: Immunoreactivity in bile ducts was expressed by the PML-score (quotient of positive ducts to the total number of portal tracts multiplied by 2). PML-score was higher in PBC as compared to controls (P < 0.001). Using a cutoff of 0.18, PML-score proved highly sensitive (84.6%) and specific (89.7%) for confirming PBC as compared to only 5% of PSC, 9.1% of NASH and 13.5% of viral hepatitis patients (P < 0.001). Irrespective of the underlying disease, patients with PML-score > 0.18 were older (P = 0.007), more often females (P < 0.001) with higher ALP (P < 0.001), γ-GT (P = 0.001) and IgM (P < 0.001) compared to the patients with PML-score < 0.18. CONCLUSIONS: We postulate that a simple PML immunohistochemical test could be sufficient for histopathological discrimination of PBC in problematic cases of undefined cholestatic disorders, including small-duct PSC and AMA-negative PBC cases.