A plasmonic biosensor pre-diagnostic tool for Familial Mediterranean Fever.

Familial Mediterranean Fever (FMF) is an autosomal recessive genetic disorder, primarily observed in populations around the Mediterranean Sea, linked to MEFV gene mutations. These mutations disrupt inflammatory responses, increasing pyrin-protein production. Traditional diagnosis relies on clinical symptoms, family history, acute phase reactants, and excluding similar syndromes with MEFV testing, which is expensive and often inconclusive due to heterozygous mutations. Here, we present a biosensor platform that detects differences in pyrin-protein levels between healthy and affected individuals, offering a cost-effective alternative to genetic testing. Our platform uses gold nanoparticle-based plasmonic chips enhanced with anti-pyrin antibodies, achieving a detection limit of 0.24 ng/mL with high specificity. The system integrates an optofluidic system and visible light spectroscopy for real-time analysis, with signal stability maintained for up to six months. Our technology will enhance FMF diagnosis accuracy, enabling early treatment initiation and providing a cost-effective alternative to genetic testing, thus improving patient care.

Complex MEFV and MVK Variations in a Syrian Child: Implications for Clinical Phenotypes and Treatment Response-A Case Report.

This case report presents a 10-year-old Syrian boy with concurrent mutations in the Mediterranean fever (MEFV) and mevalonate kinase (MVK) genes, resulting in overlapping symptoms of Familial Mediterranean Fever (FMF) and Hyperimmunoglobulinemia D syndrome (HIDS), both classified as Periodic Fever Syndromes (PFSs). The co-occurrence of these mutations within a single individual is highly unusual. He presented with pallor, intermittent fever, and recurrent respiratory infections from an early age, along with anemia, splenomegaly, hepatomegaly, cervical lymphadenopathy, and growth failure noted in initial investigations. Still's disease was initially considered as the most likely differential diagnosis, leading to the initiation of treatment with methylprednisolone; however, the parents did not follow-up with the treatment. The child returned at 5 years old with appendicitis, which was surgically removed, and parents reported recurrent episodes of arthralgia and joint swelling accompanied by nearly daily fever. Although the child experienced delayed motor development, his cognitive abilities were normal. Genetic analysis identified a homozygous likely pathogenic variant in the MVK gene and a heterozygous likely pathogenic variant in the MEFV gene. The child remains reliant on corticosteroids, with limited response to colchicine and improvement noted after transitioning from tocilizumab to infliximab. The latest follow-up demonstrated significant improvement with no fever, joint swelling, or lymphadenopathy; however, signs of growth failure persist. The atypical manifestations observed in this case may indicate a synergistic effect between the 2 mutations, contributing to the overall clinical picture. Therefore, although HIDS may dominate the clinical presentation, we cannot entirely dismiss the possibility that the FMF mutation plays a role in modulating these symptoms.

α9ß1 integrin & its ligands as new potential biomarkers in FMF.

Background & objectives Familial Mediterranean Fever (FMF) manifests as a hereditary condition characterized by repeated bouts of fever, abdominal, chest, and joint discomfort, and swelling. Colchicine is the most common form of treatment, but it does not eliminate the disease. The underlying causes of the inflammatory mechanism are still not fully known. Methods A total of 20 healthy controls, 16 individuals with FMF in the attack period, and 14 in the remission period participated in the study. ITGA9, ITGB1, OPN, TNC, VEGF, VCAM-1, TGM2, TSP-1, Emilin-1, and vWF levels were measured by ELISA by obtaining serum from blood samples of individuals. In addition, gene expressions of α9ß1 (ITGA9, ITGB1) and its best known ligands (TNC, SPP1) were analyzed by quantitative real-time PCR (qPCR). Results The findings of this study showed that serum levels of α9ß1 and its ligands were higher in individuals with FMF in the attack period than in the healthy controls and the FMF group in the remission period (P<0.05). The marker levels of the healthy group were also higher than those in the remission period (p<0.05). In addition, when the gene expressions were compared between the healthy controls and FMF group, no significant difference was found for ITGA9, ITGB1, TNC, and SPP1 genes. Interpretation & conclusions The function of α9ß1 and its ligands in FMF disease was investigated for the first time in this study as per our knowledge. Serum levels of these biomarkers may help identify potential new targets for FMF disease diagnosis and treatment approaches.

Cost-saving approach with screening of selected variants in genetic diagnosis in Turkish pediatric familial Mediterranean fever patients: a single center longitudinal study.

BACKGROUND: The aim of this study was to investigate whether a short exon screening consisting of selected variants could confirm the diagnosis in patients with a preliminary diagnosis of familial Mediterranean fever (FMF), thus providing a cost-saving alternative to a comprehensive MEditerranean FeVer (MEFV) gene sequence analysis test. METHODS: This observational study on pediatric patients focused on clinically suspected FMF cases without prior genetic analysis. Participants met the Turkish pediatric FMF criteria. They underwent short exon screening for M694V, M680I, V726A, and E148Q variants. Those who were heterozygous or negative on short exon screening received further MEFV gene sequence analysis. RESULTS: The study involved 1557 patients. Pathogenic variants in both alleles of the MEFV gene were found in 611 patients (39.2%), and a high-penetrance variant in heterozygosity or an E148Q variant on the other allele was found in 643 patients (41.3%). A further 189 patients (12.1%) had one or two E148Q variants. Short-exon screening was negative in 114 patients (7.6%). Of the 876 patients who underwent MEFV gene sequence analysis, additional variants were found in 72 of the 762 initially heterozygous patients. Of the 114 initially negative patients, 34 had homozygous or compound heterozygous variants, and 74 had heterozygous variants. Ultimately, only 6 patients yielded negative results in the MEFV gene sequence analysis. CONCLUSION: The short exon screening for common MEFV mutations offers a practical and cost-saving alternative to comprehensive MEFV gene sequence analysis in populations with a high prevalence of FMF.

Molecular investigation of MEFV gene polymorphisms among patients with familial mediterranean fever-like symptoms.

The diagnosis of familial Mediterranean fever (FMF) is primarily based on clinical standards. The purpose of this study was to investigate the relevance of Mediterranean fever (MEFV) genetic testing in the diagnosis of FMF as well as to identify the most frequent variant alleles and their relationship to clinical symptoms in Egyptian patients. Egyptian patients with a clinical suspicion of having FMF were studied in order to determine MEFV genotypes. Each patient was meticulously evaluated through an extensive collection of their medical history, a thorough clinical examination, and a series of laboratory tests, encompassing CBC, ESR, and CRP measurements. The MEFV variant screening procedure included the use of reverse dot blot hybridization. The average age of our patients when they were given a diagnosis was 22.8 ± 1.404 years old. The predominant clinical manifestations identified were abdominal pain, fever, and arthralgia.  Molecular interrogation of the MEFV gene unveiled that a significant proportion of the cohort, constituting 72 individuals (60%), displayed heterozygosity, whereas a smaller fraction, comprising 12 subjects (10%), demonstrated homozygosity and an equivalent number (10%) exhibited compound heterozygosity. Pertaining to the distribution of allele variants, E148Q emerged as the most prevalent, succeeded by M694I, accounting for 12.5% of the cases, and M680I (G/A), representing 10.41%. This notable prevalence of heterozygous genotypes among the Egyptian demographic, preliminarily identified as potential FMF cases, underscores the imperative for molecular diagnostics to enhance the precision of FMF identification.

[Challenges in diagnosing familial Mediterranean fever: exploring atypical clinical features. Clinical case].

This clinical case series presents descriptions of 3 patients with familial Mediterranean fever (FMF) who have atypical manifestations and abnormal inheritance mechanisms in terms of Gregor Mendel's laws. Although molecular genetic testing can help with disease diagnosis, it is not always conclusive. The primary need for genetic testing in atypical cases is to explain the mechanism of inflammation and to select the optimal therapy. These clinical observations demonstrate the changes in the spectrum of phenotypic manifestations of FMF in the context of the widespread introduction of molecular genetic methods.

The past 25 years in paediatric rheumatology: insights from monogenic diseases.

The past 25 years have seen major novel developments in the field of paediatric rheumatology. The concept of autoinflammation was introduced to this field, and medicine more broadly, with studies of familial Mediterranean fever, the most common autoinflammatory disease globally. New data on the positive evolutionary selection of familial Mediterranean fever-associated genetic variants might be pertinent to mild gain-of-function variants reported in other disease-associated genes. Genetic studies have unveiled the complexity of human heritability to inflammation and flourishing data from rare monogenic disorders have contributed to a better understanding of general disease mechanisms in paediatric rheumatic conditions. Beyond genomics, the application of other 'omics' technologies, including transcriptomics, proteomics and metabolomics, has generated an enormous dataset that can be applied to the development of new therapies and in the practice of precision medicine. Novel biomarkers for monitoring disease activity and progression have also emerged. A surge in the development of targeted biologic therapies has led to durable remission and improved prognosis for many diseases that in the past caused major complications. Last but not least, the COVID-19 pandemic has affected paediatric rheumatology practice and has sparked new investigations into the link between viral infections and unregulated inflammatory responses in children.

The Impact of Different MEFV Genotypes on Clinical Phenotype of Patients with Familial Mediterranean Fever: Special Emphasis on Joint Involvement.

Familial Mediterranean Fever (FMF) is the most common monogenic autoinflammatory disease worldwide. In this retrospective cohort study, we aimed to assess the effects of various MEFV genotypes on the clinical characteristics of the patients, with a special focus on the joint involvement. In total, 782 patients with FMF were categorized into 3 groups according to the MEFV mutation; Group 1: Patients homozygous for M694V; Group 2: Patients carrying other pathogenic MEFV variants in exon 10 in homozygous or compound heterozygous states; and Group 3: FMF patients with other variants or without mutations. Clinical and demographic findings were compared between groups. Among the 782 FMF patients, total frequency of arthritis was 237 (30.3%): 207 (26.4%) were acute monoarthritis and 67 (8.5%) were chronic arthritis. Both the frequency of arthritis (acute and/or chronic) (40.4% vs. 24.8% vs. 26.7%; p:0.001) and acute monoarthritis (35.4% vs. 20% vs. 23.7%; p:0.001) were significantly higher in Group 1 than in the other groups. FMF patients with chronic arthritis showed a distinct juvenile idiopathic arthritis (JIA) distribution pattern with a more frequent enthesitis-related arthritis (ERA) subtype (43.2%). HLA-B27 was positive in 24% of the ERA patients.Conclusion: Homozygous M694V mutation is associated with a more frequent and longer acute monoarthritis comparing to other MEFV genotypes. In addition, the risk of chronic arthritis seems not related to the MEFV mutations. However, FMF patients with chronic arthritis show a distinct ILAR JIA distribution pattern with a more frequent ERA and undifferentiated arthritis subtype. What is known: • Homozygous M694V mutation is associated with a more frequent and longer acute monoarthritis What is new: • FMF patients with chronic arthritis show a distinct ILAR JIA distribution pattern with a more frequent ERA subtype • ERA patients with negative HLA-B27 antigen should also be assessed for polyserositis episodes of FMF, especially in countries with high FMF carrier frequency.

E148Q variant: a familial Mediterranean fever-causing mutation or a sequence variant?

Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disease, linked to mutations in the MEFV gene. The p.E148Q variant, found on exon 2, has an uncertain role in FMF, with debates on whether it is a benign polymorphism or a pathogenic mutation. This study aimed to assess the clinical characteristics and severity of FMF in patients homozygous for the p.E148Q variant and to evaluate the impact of the p.V726A variant in these patients. This retrospective cohort study analyzed data from electronic medical records at Carmel Medical Center, Israel. Patients who underwent genetic testing for FMF from November 2004 to December 2019 and had p.E148Q/p.E148Q or p.E148Q/p.E148Q + p.V726A variants were included. Disease severity was assessed using the Tel Hashomer Key to Severity Score. Statistical analyses compared clinical characteristics and severity between genotype groups. The study included 61 FMF patients, with 24 (39%) having p.E148Q/p.E148Q and 37 (61%) having p.E148Q/p.E148Q + p.V726A variants. The majority (72%) were Druze. Most patients (65.5%) exhibited mild disease, while 31.1% had moderate disease, with no cases of severe disease. Colchicine treatment significantly reduced CRP levels in all patients. CONCLUSION: These findings suggest that the p.E148Q variant, whether alone or with p.V726A, generally results in mild to moderate FMF severity, supporting its pathogenic role in particular ethnicity. These results contribute to understanding the clinical significance of the p.E148Q variant and considering the patient's need for Colchicine treatment. WHAT IS KNOWN: • The role of the p.E148Q variant in FMF is debated, with questions about whether it is a benign polymorphism or a pathogenic mutation. • The prevalence of MEFV variants can vary significantly among different ethnic groups. WHAT IS NEW: • The p.E148Q variant has clinical significance in particular ethnicities, as supported by a significant reduction in CRP levels following colchicine treatment. • The p.E148Q variant, whether alone or with p.V726A, generally results in mild to moderate FMF severity.

How do gene mutation diversity and disease severity scoring affect physical capacity and quality of life in children/adolescents with Familial Mediterranean Fever?

OBJECTIVES: The aim of this study is to examine how gene mutation diversity and disease severity affect physical capacity and quality of life in children/adolescents with Familial Mediterranean Fever (FMF). METHODS: Eighty children/adolescents (42 female, 38 male) diagnosed with FMF according to Tell-Hashomer diagnostic criteria were included in this study. Disease severity score (PRAS), running speed and agility and strength subtests of Bruininks-Oseretsky Test of Motor Proficiency Second Edition Short Form (BOT-2 SF), Physical Activity Questionnaire, Pediatric Quality of Life Inventory 3.0 Arthritis Module (PedsQL) was used for evaluation. Participants were divided into 2 groups as M694V and other mutations according to MEFV gene mutation and were divided into 3 groups as mild, moderate and severe according to PRAS. RESULTS: When the data were compared between groups; in terms of gene mutation, a significant difference was observed in treatment subtest of PedsQL-parent form in favor of the M694V gene mutation group (p<0.05). In terms of PRAS, significant difference was seen in the pain, treatment subtests and total score of the PedsQL-child form, and in the pain, treatment, worry subtests and total score of the PedsQL-parent form in favor of the mild group (p<0.05). CONCLUSIONS: MEFV gene mutations in children and adolescents with FMF did not differ on physical capacity and quality of life. PRAS was not effective on physical parameters, but quality of life decreased as the severity score increased. Encouraging children/adolescents with FMF to participate in physical activity and to support them psychosocially can be important to improve their quality of life.

Comparison of Clinical and Genetic Characteristics of Familial Mediterranean Fever Patients Among Adult Age Groups.

Familial mediterranean fever (FMF) is a genetic autoinflammatory disease typically diagnosed in childhood. In this study, we aimed to investigate the demographic, clinical, and genetic characteristics of patients aged 18 years and older who were diagnosed with FMF. Patients diagnosed with FMF between 2014 and 2022 at Karadeniz Technical University Faculty of Medicine Hospital were included in the study. Patients were divided into 2 groups based on the age of disease onset. Group I included patients with adult-onset (ages 18-40), while group II comprised patients with late onset (ages 40 and above). Subsequently, the 2 groups were compared. A total of 150 patients with a mean age of 32 (18-79) were included in the study. There were 116 patients in group I and 34 (22.7%) in group II. The most common presenting complaint was abdominal pain (91.3%), and the most prevalent complication was amyloidosis (4.7%). No significant differences were observed between age groups regarding clinical findings and symptoms. The most frequent homozygous mutations were M694V (9.3%) and R202Q (1.8%), while the heterozygous mutations were M694V (37.3%) and R202Q (35.5%), respectively. The rate of M694V gene positivity in the adult-onset group was significantly higher compared to the lateonset group (52.9% and 25%, respectively, P = .020). There does not appear to be a significant difference in clinical signs and symptoms between adult-onset and late-onset FMF patients. The higher rate of M694V gene positivity in the adult-onset group suggests that the M694V mutation may be responsible for the early expression of the disease.

Clinical Associations of E148Q Heterozygosity: What to Expect From E148Q?

OBJECTIVE: The exact effects of MEFV variants on inflammation are still under investigation, and reports on variants of unknown significance, particularly the E148Q variant, have been conflicting. Therefore, this study aims to investigate patients exhibiting E148Q heterozygosity, focusing on diagnoses and disease courses to assist physicians in interpreting the variant. METHODS: Data of pediatric patients presenting to the Pediatric Rheumatology clinic between November 2016 and September 2023, exhibiting only E148Q heterozygosity in MEFV gene analysis, were extracted. Patients who were lost before 9 months of follow-up have been excluded to ensure the completion of initial diagnostic tests and evaluations. RESULTS: Among the 119 patients with E148Q variant, the diagnoses were as follows: healthy, 51.3%; IgA vasculitis, 10.1%; Familial Mediterranean Fever (FMF), 7.6%; Periodic fever, Aphtous stomatitis, Pharyngitis, Adenitis (PFAPA), 6.7%; and other diagnoses, 19.3%. IgA vasculitis patients experienced articular, gastrointestinal, and renal involvement at rates of 91.7%, 58.3%, and 16.7%, respectively. Complete response, partial response, and no response to colchicine were 37.5%, 12.5%, and 50%, respectively, in PFAPA patients. All FMF patients responded to colchicine treatment resulting in reduced mean FMF episode counts in 6 months from 3.22 ± 0.92 to 0.56 ± 0.52. CONCLUSIONS: The E148Q variant may amplify inflammation and modify disease courses. Patients with the E148Q variant experiencing typical FMF episodes should receive colchicine, but clinicians should exercise caution regarding alternative diagnoses. Additionally, the E148Q variant may increase acute phase reactants and disease severity in IgA vasculitis. However, to reach definitive conclusions on its treatment-modifying role in PFAPA, universal diagnosis and treatment response criteria should be adopted.

Plasminogen activator inhibitor-1 genotype 4G/5G associates with skin involvement in Armenian familial Mediterranean fever patients.

There is little and conflicting data on the role of the plasminogen activator inhibitor-1 (PAI-1, SERPINE1) 4G/5G polymorphism in familial Mediterranean fever (FMF). Therefore this study aimed at evaluating the impact of this polymorphism on the disease course in a cohort of 303 Armenian FMF patients. Genotyping for 12 Mediterranean fever (MEFV) gene mutations and the PAI-1 4G/5G (rs1799762) polymorphism were performed by PCR/reverse-hybridization (StripAssay) and real-time PCR, respectively. PAI-1 genotypes 4G/4G, 4G/5G, and 5G/5G could be identified in 4 (5.88%), 30 (18.63%) and 9 (12.16%) patients with erysipelas-like erythema (ELE), while this was the case for 64 (94.12%), 131 (81.37%), and 65 (87.84%) patients without ELE, respectively (P < 0.033). We have identified a significant relationship between the PAI-1 4G/5G genotype and the occurence of ELE in a relatively large cohort of Armenian FMF patients. Because of conflicting results concerning the impact of this polymorphism on the clinical course of FMF in different populations, further studies are desirable to substantiate the findings reported here.

Molecular analyses of MEFV gene mutation variants in Turkish population.

BACKGROUND: Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disease primarily affecting individuals of Turkish, Armenian, Arab, and non-Ashkenazi Jewish descent, caused by mutations in the MEFV gene. The aim of this study was to review the common genotype distributions of MEFV variants and mutations in the Turkish population and evaluate rare mutations. METHODS AND RESULTS: The study included 2984 patients who applied to Ankara University Ibni Sina Hospital Immunology Laboratory with clinical suspicion of FMF between 2004 and 2014. The data of patients from different regions of the country who were followed up in the immunology-rheumatology clinic with clinical suspicion and presumptive diagnosis of FMF were evaluated retrospectively. Patients were tested for all mutations in Exon 2 and Exon 10, including M694V, M680I, M694I, V726A, E148Q and R202Q. There were 2504 patients with FMF variant. According to genotyping, R202Q (n = 1567, 39.2%) was the most common mutation. The most common co-variant was the R202Q/M694V genotype (n = 507, 16.98%). Allele frequencies for MEFV mutations were as follows: R202Q (n = 1567, 39.2%), M694V (n = 1004, 25.1%), E148Q (n = 463, 11.5%), M680I (n = 354, 8.8%), V726A (n = 319, 7.9%), A744S (n = 51, 1.2%), R761H (N = 41, 1.0%), P706P (N = 25, 0.6%), E167D (N = 23, 0.5%), M694I (N = 23, 0.5%), and K695R (N = 20, 0.5%). CONCLUSION: This research revealed the prevalence of both common and rare MEFV gene mutations in Turkish FMF patients in various age groups. R202Q was the most prevalent mutation.

Generation of iPSCs from a Patient with the M694V Mutation in the MEFV Gene Associated with Familial Mediterranean Fever and Their Differentiation into Macrophages.

Familial Mediterranean fever (FMF) is a systemic autoinflammatory disorder caused by inherited mutations in the MEFV (Mediterranean FeVer) gene, located on chromosome 16 (16p13.3) and encoding the pyrin protein. Despite the existing data on MEFV mutations, the exact mechanism of their effect on the development of the pathological processes leading to the spontaneous and recurrent autoinflammatory attacks observed in FMF, remains unclear. Induced pluripotent stem cells (iPSCs) are considered an important tool to study the molecular genetic mechanisms of various diseases due to their ability to differentiate into any cell type, including macrophages, which contribute to the development of FMF. In this study, we developed iPSCs from an Armenian patient with FMF carrying the M694V, p.(Met694Val) (c.2080A>G, rs61752717) pathogenic mutation in exon 10 of the MEFV gene. As a result of direct differentiation, macrophages expressing CD14 and CD45 surface markers were obtained. We found that the morphology of macrophages derived from iPSCs of a patient with the MEFV mutation significantly differed from that of macrophages derived from iPSCs of a healthy donor carrying the wild-type MEFV gene.

Altered expression of miR-17 and miR-148b in pediatric familial mediterranean fever patients.

Familial Mediterranean fever (FMF) is a recessively inherited autoinflammatory disorder with wide phenotypic variation that has been observed among individuals who have the same genotype. Modifying genes, epigenetic factors, or environmental factors might all have an impact on genotype-phenotype correlation in FMF. The current research aims to determine the expression levels of microRNAs (miR-148b and miR-17) in Egyptian FMF participants. We also aimed to investigate Caspase -1 gene expression to make a correlation with disease severity. The study comprised 25 clinically diagnosed FMF cases and 25 healthy subjects matched for age and sex. The molecular diagnosis of FMF cases was assessed using real-time SNP genotyping assay. MiR-148b and miR-17 expression were profiled using TaqMan assay technology. The expression level of Caspase -1 gene was also verified using qRT-PCR. MiR-17 in the studied cases was significantly upregulated compared to healthy individuals (P = 0.006), whereas miR-148b was significantly downregulated in the examined patients (P = 0.030). Moreover, statistically significant upregulation of Caspase-1 expression was also elucidated in relation to normal subjects (P = 0.033). The results obtained indicated that miR-17 and miR-148b might be potential regulatory biomarkers in FMF cases. We further hypothesized that the upregulation of Caspase-1 could hint at its significance as a future therapeutic target to alleviate the inflammatory process in these patients. Key Points • The role of miRNAs in FMF and various mechanisms involved in FMF pathogenesis has received increasing attention. • Studying the expression profiles of miR-17 and miR-148b in FMF patients revealed their potential role as regulatory biomarkers in these patients. • Significant upregulation of Caspase-1 expression in FMF cases could hint at its significance as a future therapeutic target. • Future studies on larger cohorts are warranted to clarify and better understand the role of miRNAs in the pathogenesis and severity of FMF.