Epigenetic, transcriptional, and functional characterization of myeloid cells in familial Mediterranean fever

Familial Mediterranean fever (FMF) is a periodic fever syndrome caused by variation in MEFV. FMF is known for IL-1β dysregulation, but the innate immune landscape of this disease has not been comprehensively described. Therefore, we studied circulating inflammatory proteins, and the function of monocytes and (albeit less extensively) neutrophils in treated FMF patients in remission. We found that monocyte IL-1β and IL-6 production was enhanced upon stimulation, in concordance with alterations in the plasma inflammatory proteome. We did not observe changes in neutrophil functional assays. Subtle differences in chromatin accessibility and transcriptomics in our small patient cohort further argued for monocyte dysregulation. Together, these observations suggest that the MEFV-mutation-mediated primary immune dysregulation in monocytes leads to chronic inflammation that is subsequently associated with counterregulatory epigenetic/transcriptional changes reminiscent of tolerance. These data increase our understanding of the innate immune changes in FMF, aiding future management of chronic inflammation in these patients.

Inflammatory markers in rheumatic diseases

Immune-mediated rheumatic diseases (IMRDs) are a broad group of pathological conditions based on impaired immunological tolerance to one’s own tissues leading to inflammation and irreversible organ damage. Laboratory diagnosis of IMRDs includes a wide range of biomarkers (autoantibodies, acute phase proteins, cytokines, markers of endothelial damage, components of the complement system, immunoglobulins, cryoglobulins, lymphocyte subpopulations, indicators of bone metabolism, apoptosis markers, genetic markers, etc). One of the leading aspects of laboratory diagnosis of IMRDs is the study of the level of inflammation markers in the blood (erythrocyte sedimentation rate, C-reactive protein (CRP), serum amyloid protein (CAA), ferritin, procalcitonin, apolipoprotein AI, calprotectin, etc). The analysis of inflammation markers makes it possible to assess the disease activity, the nature of the progression and the prognosis of the outcomes of a chronic inflammatory process, as well as the effectiveness of the therapy. The review presents the latest data on the role of the most frequently studied inflammatory markers such as CRP, CAA and ferritin.

Dysregulated inflammasome activity in intestinal inflammation - Insights from patients with very early onset IBD

Inflammatory bowel disease (IBD) is a multifactorial disorder triggered by imbalances of the microbiome and immune dysregulations in genetically susceptible individuals. Several mouse and human studies have demonstrated that multimeric inflammasomes are critical regulators of host defense and gut homeostasis by modulating immune responses to pathogen- or damage-associated molecular patterns. In the context of IBD, excessive production of pro-inflammatory Interleukin-1β has been detected in patient-derived intestinal tissues and correlated with the disease severity or failure to respond to anti-tumor necrosis factor therapy. Correspondingly, genome-wide association studies have suggested that single nucleotide polymorphisms in inflammasome components might be associated with risk of IBD development. The relevance of inflammasomes in controlling human intestinal homeostasis has been further exemplified by the discovery of very early onset IBD (VEO-IBD) patients with monogenic defects affecting different molecules in the complex regulatory network of inflammasome activity. This review provides an overview of known causative monogenic entities of VEO-IBD associated with altered inflammasome activity. A better understanding of the molecular mechanisms controlling inflammasomes in monogenic VEO-IBD may open novel therapeutic avenues for rare and common inflammatory diseases.

Clinical perspectives and therapeutic strategies: pediatric autoinflammatory disease-a multi-faceted approach to fever of unknown origin of childhood

Among the different etiologies for fever of unknown origin in children, infectious diseases are the most frequent final diagnosis, followed by autoimmune diseases and malignancies. Autoinflammatory diseases are relatively rare among children and are frequently overlooked as differential diagnoses for fever of unknown origin. Once the possibility of a particular autoimmune disease is considered by physicians, the diagnosis might be easily made by a genetic approach because many of autoinflammatory diseases are of monogenic origin. To reach the diagnosis, detailed history-taking, precise physical examinations, and cytokine profiling as well as extensive mutation analysis of candidate genes should be undertaken for febrile children. Such the approach will protect the patients, and their family to undergo “diagnostic odyssey” in which unnecessary and sometimes risky diagnostic and therapeutic interventions are taken.

This short review discusses the clinical and laboratory features of familial Mediterranean fever and systemic juvenile idiopathic arthritis, as representative illnesses of monogenic and polygenic autoinflammatory diseases, respectively. Cytokine profiling and mutation analyses both help to understand and decipher the heterogeneous pathologies in both disease categories.

Efficacy and safety of canakinumab for colchicine-resistant or colchicine-intolerant familial Mediterranean fever: A single-centre observational study

OBJECTIVES

To evaluate the efficacy and safety of canakinumab in Japanese patients with colchicine-resistant or colchicine-intolerant familial Mediterranean fever (FMF) in a real-world clinical setting.

METHODS

We reviewed 13 Japanese FMF patients to whom canakinumab was introduced during the period of October 2017 to December 2020. All patients were diagnosed as FMF according to Tel-Hashomer criteria. We performed genetic analyses for Mediterranean fever or MEFV by targeted next-generation sequencing. Efficacy was assessed by attack frequency and the percentage of patients who achieved attack improvement at 24 weeks. Safety was assessed by adverse events observed during canakinumab treatment.

RESULTS

The median duration and follow-up of canakinumab treatment were 13 and 16 months, respectively. The median attack frequency was 0.50 [0.30-1.00] at 24 weeks, which was a significant decrease from 2.00 [0.85-2.88] at the time of induction (p = .019). There were three patients (23%) with complete resolution of attacks at 24 weeks. No serious adverse events were observed. However, one patient had small intestinal ulceration which led to the discontinuation of canakinumab.

CONCLUSIONS

Although the number of cases is small, this study suggests that canakinumab is efficacious and safe for use in Japanese patients with colchicine-resistant or colchicine-intolerant FMF in a real-world clinical setting in Japan.

Serum Amyloid A in Inflammatory Rheumatic Diseases: A Compendious Review of a Renowned Biomarker

Serum amyloid A (SAA) is an acute phase protein with a significant importance for patients with inflammatory rheumatic diseases (IRD). The central role of SAA in pathogenesis of IRD has been confirmed by recent discoveries, including its involvement in the activation of the inflammasome cascade and recruitment of interleukin 17 producing T helper cells. Clinical utility of SAA in IRD was originally evaluated nearly half a century ago. From the first findings, it was clear that SAA could be used for evaluating disease severity and monitoring disease activity in patients with rheumatoid arthritis and secondary amyloidosis. However, cost-effective and more easily applicable markers, such as C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR), overwhelmed its use in clinical practice. In the light of emerging evidences, SAA has been discerned as a more sensitive biomarker in a wide spectrum of IRD, especially in case of subclinical inflammation. Furthermore, a growing number of studies are confirming the advantages of SAA over many other biomarkers in predicting and monitoring response to biological immunotherapy in IRD patients. Arising scientific discoveries regarding the role of SAA, as well as delineating SAA and its isoforms as the most sensitive biomarkers in various IRD by recently developing proteomic techniques are encouraging the revival of its clinical use. Finally, the most recent findings have shown that SAA is a biomarker of severe Coronavirus disease 2019 (COVID-19). The aim of this review is to discuss the SAA-involving immune system network with emphasis on mechanisms relevant for IRD, as well as usefulness of SAA as a biomarker in various IRD. Therefore, over a hundred original papers were collected through an extensive PubMed and Scopus databases search. These recently arising insights will hopefully lead to a better management of IRD patients and might even inspire the development of new therapeutic strategies with SAA as a target.

[Results of the systematic literature search as basis for the "Evidence-based treatment recommendations for familial Mediterranean fever patients with insufficient response or intolerability to colchicine" of the Society for Pediatric and Adolescent Rheumatology and the German Society for Rheumatology]

BACKGROUND

Familial Mediterranean fever (FMF) is a genetic disease of childhood and adulthood which is relatively rare in Germany. It is characterized by recurrent febrile attacks, peritonitis, pleuritis and arthritis. The established treatment with colchicine is effective and well-tolerated by most patients; however, some patients do not adequately respond or do not tolerate this treatment. Biologics can be considered for some of these patients. The Society for Pediatric and Adolescent Rheumatology (GKJR) and the German Society for Rheumatology (DGRh) have agreed to develop joint recommendations for this specific clinical situation.

AIM

Implementation of a systematic literature search (SLR) on the basis of the EULAR recommendations published in 2016 as the foundation for the development of evidence-based treatment recommendations for FMF patients with insufficient response or intolerance to colchicine.

METHODS

The SLR was performed using references from various databases as an update of the SLR carried out by EULAR up to 2014, whereby all articles must have been published between 1 January 2015 and 31 December 2017. The Rayyan abstract tool for the preselection and the classification of the Oxford Centre for Evidence Based Medicine 2009 were used for the preparation of the evidence tables.

RESULTS

The search yielded 360 hits and after duplicate matching 263. A total of 88 publications were included (34%) and 102 excluded (39%), a review of the full publication was necessary for a further 73 (28%) and 43 were discussed more intensively. Finally, 64 publications (24%) remained. A total of 4 case-control studies, 31 cohort studies, 8 case series, 7 controlled studies (including 5 abstracts), 10 reviews, 4 meta-analyses and systematic reviews were accepted.

DISCUSSION

The SLR was carried out in a scientifically accurate and transparent manner according to international standards. The SLR proved to be a good basis for a consensus on the 5 overarching principles and the 10 recommendations, so that the joint activity of the GKJR and DGRh was successfully and even promptly concluded. The recommendations are a solid basis for treating patients of all ages with FMF. The explanations on the problem of colchicine resistance play an important role here.

Long-term efficacy and safety of canakinumab in patients with colchicine-resistant familial Mediterranean fever: results from the randomised phase III CLUSTER trial

Objectives

To evaluate the long-term efficacy and safety of canakinumab to treat patients with colchicine-resistant familial Mediterranean fever (crFMF) during Epoch 4 (weeks 41 to 113) of the CLUSTER study.

Methods

Patients received open-label canakinumab 150 or 300 mg, every 4 or 8 weeks during a 72-week period. We evaluated disease activity every 8 weeks using the physician global assessment (PGA) of disease activity, counting the number of flares, and measuring concentrations of C reactive protein (CRP) and serum amyloid A (SAA). Safety was studied by determination and classification of observed adverse events (AEs). We analysed safety and efficacy separately in two subgroups of patients receiving a cumulative dose of less than 2700 mg, or equal or more than 2700 mg.

Results

Of the 61 patients that started the CLUSTER study, 60 entered Epoch 4 and 57 completed it. During the 72-week period, 35/60 (58.3%) patients experienced no flares, and 23/60 (38.3%) had one flare, as compared with a median of 17.5 flares per year reported at baseline. PGA scores indicated no disease activity for the majority of patients throughout the study. Median CRP concentrations were always lower than 10 mg/L, while median SAA concentrations remained over the limit of normal (10 mg/L) but under the 30 mg/L threshold. No new or unexpected AEs were reported.

Conclusion

crFMF patients treated with canakinumab during 72 weeks experienced a minimal incidence of flares and good control of clinical disease activity, with no new safety concerns reported.

Long-term effectiveness and safety of canakinumab in pediatric familial Mediterranean fever patients

Background: Little is known about the long-term efficacy and safety of canakinumab in paediatric FMF patients.Aim: To present the single centre experience of colchicine-resistant paediatric-onset FMF patients who were treated with canakinumab by off-label use since 2012.Methods: The hospital files of 15 children who used canakinumab were retrospectively evaluated. Clinical and laboratory data of each visit were recorded. Drug-related adverse events were recorded. Complete remission was described as no attacks and normal acute phase reactants; partial remission was defined as decrease in severity and rate of attacks and/or elevated acute phase reactants with anti-IL-1 treatment.Results: The average duration of canakinumab use was 23.9 months (min:12, max:58 months). Twelve patients were M694V homozygotes. Eleven patients achieved complete remission after the first dose at 2 months and 12 patients at 6 months. Canakinumab interval was shortened in 2 patients from 150 mg/8 weeks to 150 mg/4 weeks. Except one, 14 patients achieved complete remission by 12 months. Two patients had mild urinary tract infections. One patient had bronchopneumonia requiring hospitalization. Two patients had teeth abscess. There were no serious adverse events such as opportunistic infections, malignancies, or deaths. Besides, no significant laboratory abnormalities occurred in complete blood count parameters, liver and kidney function tests.Conclusion: To the best of our knowledge, this is the longest outcome study about canakinumab use in paediatric FMF patients. This study suggested that canakinumab is safe and effective in children with FMF in the long term.

Familial Mediterranean fever: overview of pathogenesis, clinical features and management

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease, and is characterized by recurrent attacks of fever and polyserositis. It is associated with mutations in the MEFV gene encoding pyrin, which result in inflammasome activation and the uncontrolled production of IL-1β. FMF mainly affects individuals originating from the Mediterranean basin; however, a Japanese nationwide survey demonstrated that FMF is not uncommon in Japan. The survey also indicated that Japanese FMF patients are clinically or genetically distinct from Mediterranean FMF patients, suggesting a genotype-phenotype correlation. In Japanese patients with FMF, MEFV exon 10 mutations are associated with the more typical FMF phenotype. Conversely, Japanese FMF patients with mutations in MEFV exons 2 or 3 present with an atypical FMF phenotype. Colchicine is the mainstay of FMF treatment, and its regular use prevents febrile attacks and decreases the long-term risk of AA amyloidosis. However, a minority of FMF patients are colchicine-resistant, and anti-IL-1 treatment has proven beneficial in suppressing inflammation in these patients. Although Japanese FMF patients may develop less severe disease compared with Mediterranean FMF patients, they should nevertheless be treated early to prevent recurrent attacks and the subsequent development of AA amyloidosis.

Can the Thiol/Disulfide Imbalance Be a Predictor of Colchicine Resistance in Familial Mediterranean Fever?

Familial Mediterranean fever (FMF) is a chronic autoinflammatory condition characterized by fever attacks and recurrent polyserositis. Subclinical inflammation that persists during attack-free periods can result in oxidative stress (OS) damage. Thiol groups bind to reactive oxygen radicals and protect cells and tissues from OS damage. The aim of this study was to investigate the relationship between thiol-disulfide balance and colchicine resistance in FMF patients during an attack or attack-free period. A newly developed spectrophotometric method was used to measure native thiol (NT) and disulfide (DS) levels in FMF patients and an age-sex matched group of healthy controls. NT and DS levels were compared in FMF patients 1) with vs. without colchicine resistance; and 2) during an attack (FMF-AP) vs. attack-free period (FMF-AFP). A total of 118 FMF patients and 60 healthy controls were studied. NT (P < 0.001) and total thiol (TT) (P < 0.001) levels in FMF patients were significantly lower compared to healthy controls. NT (P = 0.030) and TT (P = 0.010) levels of FMF-AP patients were significantly lower than that of FMF-AFP patients. FMF-AP patients had significantly higher DS levels than FMF-AFP patients (P = 0.039). Compared to FMF patients without colchicine resistance, elevated levels of DS (P = 0.019) but not NT (P = 0.620) and TT (P = 0.718) were found in those with colchicine resistance. Thiol-disulfide homeostasis is altered in FMF patients during an attack period and this imbalance may be associated with colchicine resistance.

Longterm Beneficial Effect of Canakinumab in Colchicine-resistant Familial Mediterranean Fever

Objective.

To assess the efficacy and safety of the interleukin-1β (IL-1β) inhibitor canakinumab in all adolescent and adult patients with familial Mediterranean fever (FMF) identified from the Greek National Registry for off-label drug use between 2010 and 2015.

Methods.

In this retrospective longitudinal outcome study, clinical and laboratory data were collected from 14 patients (7 men) aged median 38.5 years (range 13–70), with median disease duration of 14 years, and active FMF despite colchicine (n = 9) or both colchicine and anakinra (n = 5).

Results.

All patients continued to receive canakinumab at last visit (median of 18 mos, range 13–53), which was initially given as monotherapy (n = 8) or in combination with colchicine and/or corticosteroids, every 4 (n = 7), 6 (n = 2), or 8 weeks (n = 5). Eleven patients (79%), including 6 receiving monotherapy, achieved complete clinical remission within 2 months (median), while normalization of all laboratory variables denoting inflammation occurred in 92% at 3 months (median). The remaining 3 patients achieved partial responses. Responses were sustained in all but 4 patients, who relapsed. Reducing the canakinumab administration interval from 8 or 6 weeks to 4 weeks led to suppression of disease activity in the relapsing patients. On the other hand, drug administration interval could be safely increased in 2 patients in remission. Corticosteroid doses were significantly reduced during followup. Canakinumab was well tolerated; 1 patient experienced a urinary tract infection and another one a viral gastroenteritis.

Conclusion.

Treatment with canakinumab in an individualized dosing scheme results in rapid and sustained remission in colchicine-resistant FMF.

Acute exacerbation of rheumatoid interstitial lung disease during the maintenance therapy with certolizumab pegol

We report a case involving a 68-year-old woman with rheumatoid arthritis (RA) with acute exacerbated interstitial lung disease (ILD) during certolizumab pegol maintenance therapy. She recovered quickly with steroid pulse therapy and was discharged without deterioration of basal pulmonary function. Immunoblot analysis demonstrated the circulating cleaved interleukin-1β at the phase of acute exacerbation of RA-associated ILD (RA-ILD) in this patient. The findings from this case suggested that the Nod-like receptor pyrin domain-containing protein 3 inflammasome is implicated in acute RA-ILD exacerbation.

Increased prevalence of MEFV exon 10 variants in Japanese patients with adult-onset Still's disease

Autoinflammatory diseases include a large spectrum of monogenic diseases, e.g. familial Mediterranean fever (FMF), as well as complex genetic trait diseases, e.g. adult-onset Still's disease (AOSD). In populations where FMF is common, an increased MEFV mutation rate is found in patients with rheumatic diseases. The aim of this study was to examine MEFV mutations in Japanese patients with AOSD. Genomic DNA was isolated from 49 AOSD patients and 105 healthy controls, and exons 1, 2, 3 and 10 of the MEFV gene genotyped by direct sequencing. MEFV mutation frequencies in AOSD patients were compared with controls. We found no significant difference in overall allele frequencies of MEFV variants between AOSD patients and controls. However, MEFV exon 10 variants (M694I and G632S) were significantly higher in AOSD patients than controls (6.1 versus 0%). In addition, there was no significant difference between MEFV variant carriers and non-carriers with clinical manifestations, but the monocyclic clinical course of the AOSD disease phenotype was observed less frequently in patients without MEFV variants. AOSD patients had significantly higher frequencies of MEFV exon 10 mutations, suggesting that low-frequency variants of MEFV gene may be one of the susceptibility factors of AOSD.