E148Q is a disease-causing MEFV mutation: a phenotypic evaluation in patients with familial Mediterranean fever

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.

The Role of Tenascin-C in the Physiopathology of Familial Mediterranean Fever

OBJECTIVE

Familial Mediterranean fever (FMF) is an autoinflammatory disease common in the Mediterranean basin. It has been determined that tenascin-C level is increased in rheumatic inflammatory diseases such as rheumatoid arthritis (RA), systemic lupus erythematosus, and systemic sclerosis. However, the role of tenascin-C has not been investigated in FMF. This study aimed to investigate serum tenascin-C levels in FMF patients and to investigate possible relationships between them.

MATERIALS AND METHODS

About 38 patients diagnosed with FMF and 40 healthy controls were included in the study. The patient's sex, age, clinical symptoms, physical examination, and laboratory results were recorded. Serum tenascin-C levels were determined by the enzyme-linked immunosorbent assay (ELISA) method.

RESULTS

The serum tenascin-C levels were significantly lower in the FMF patients (10297 ± 8107 pg/ml) compared to the healthy control group (29461 ± 13252 pg/ml) (p < 0.001). In receiver operating characteristic (ROC) analysis, when the cut-off point was chosen as 11076 pg/ml, sensitivity was 77.1% and specificity was 91.9%. When the cut-off point was chosen as 19974 pg/ml, sensitivity was 91.4% and specificity was 75.7%. It was determined that the serum tenascin-C levels did not correlate with age, gender, and laboratory parameters in the healthy control group and FMF patients (p > 0.05).

CONCLUSION

This is the first study investigating tenascin-C levels in FMF. Tenascin-C levels in FMF patients were lower than in healthy controls. Low tenascin-C levels in FMF, which are high in other chronic rheumatic diseases, may be a valuable indicator. Therefore, serum tenascin-C level seems to be a useful marker in distinguishing FMF patients from healthy individuals.

Evaluation of cardiac functions in children with familial Mediterranean fever

OBJECTIVES

Familial Mediterranean fever is an autosomal recessive autoinflammatory inherited disease. We aimed to evaluate cardiac involvement in children with familial Mediterranean fever during the attack-free period.

MATERIAL AND METHODS

The prospective study included 75 familial Mediterranean fever patients during the attack-free period and 50 healthy children. Cardiac evaluation was performed using electrocardiography, 24-hour ambulatory Holter monitoring, and conventional and tissue Doppler echocardiography. Aortic stiffness indices were calculated.

RESULTS

There were no differences between the groups in age, height, sex, body mass index, and arterial blood pressure parameters (p > 0.05). QT and corrected QT dispersion parameters were similar in both groups (p > 0.05). The E wave velocity and the E/A ratio of the mitral and tricuspid valves decreased, and the A wave velocity of the tricuspid and mitral valve increased in familial Mediterranean fever by the Doppler echocardiography (p < 0.05). The myocardial contraction velocities (Sd), early relaxation velocity (Ed), and Ed/late relaxation velocity (Ad) of both ventricles were decreased in familial Mediterranean fever group, whereas the Ad of both ventricles and the interventricular septum was increased in familial Mediterranean fever group. Aortic strain and distensibility were decreased, and pressure strain elastic modules (Ep), pressure strain normalised (Ep*) by diastolic pressure, and aortic stiffness β index were increased in familial Mediterranean fever patients (p < 0.05). When time domain heart rate variability parameters were evaluated, SDNN-i, RMSSD, and PNN50 significantly decreased in familial Mediterranean fever patients (p < 0.05), whereas SDNN and SDANN were similar in both groups (p > 0.05).

CONCLUSION

Our findings showed that cardiac involvement could exist in familial Mediterranean fever patients, even during nonattack periods.

Pyrin variant E148Q potentiates inflammasome activation and the effect of pathogenic mutations in cis

OBJECTIVE

The p.E148Q variant in pyrin is present in different populations at a frequency of up to 29%, and has been associated with diseases, including vasculitis and FMF. The pathogenicity of p.E148Q in FMF is unclear, even when observed in cis or in trans to a single, typically recessive, pathogenic mutation. We performed functional validation to determine whether p.E148Q increases the ability of pyrin to form an active inflammasome complex in cell lines.

METHODS

We interrogated the Australian Autoinflammatory Disease RegistrY (AADRY) to find candidate inheritance patterns for the p.E148Q variant in pyrin. Different pyrin variant combinations were tested in HEK293T cells stably expressing the adaptor protein apoptosis-associated speck-like (ASC), which were analysed by flow cytometry to visualize inflammasome formation, with and without stimulation by Clostridioides difficile toxin B (TcdB). Inflammasome-dependent cytokine secretion was also quantified by ELISA of supernatants from THP-1 cells transduced with lentiviral expression vectors.

RESULTS

In AADRY, we observed the p.E148Q allele in individuals with autoinflammatory diseases alone or in conjunction with other pyrin variants. Two FMF families harboured the allele p.E148Q-M694I in cis with dominant heritability. In vitro, p.E148Q pyrin could spontaneously potentiate inflammasome formation, with increased IL-1β and IL-18 secretion. p.E148Q in cis to classical FMF mutations provided significant potentiation of inflammasome formation.

CONCLUSION

The p.E148Q variant in pyrin potentiates inflammasome activation in vitro. In cis, this effect is additive to known pathogenic FMF mutations. In some families, this increased effect could explain why FMF segregates as an apparently dominant disease.

Patient Experiences and Challenges in the Management of Autoinflammatory Diseases-Data from the International FMF & AID Global Association Survey

BACKGROUND

Autoinflammatory diseases (AIDs) are rare, mostly genetic diseases that affect the innate immune system and are associated with inflammatory symptoms. Both paediatric and adult patients face daily challenges related to their disease, diagnosis and subsequent treatment. For this reason, a survey was developed in collaboration between the FMF & AID Global Association and the Erlangen Center for Periodic Systemic Autoinflammatory Diseases.

METHODS

The aim of the survey was to collect the personal assessment of affected patients with regard to their current status in terms of diagnostic timeframes, the interpretation of genetic tests, the number of misdiagnoses, and pain and fatigue despite treatment.

RESULTS

In total, data from 1043 AID patients (829 adults and 214 children/adolescents) from 52 countries were collected and analyzed. Familial Mediterranean fever (FMF) (521/50%) and Behçet's disease (311/30%) were the most frequently reported diseases. The average time to diagnosis was 3 years for children/adolescents and 14 years for adults. Prior to the diagnosis of autoinflammatory disease, patients received several misdiagnoses, including psychosomatic disorders. The vast majority of patients reported that genetic testing was available (92%), but only 69% were tested. A total of 217 patients reported that no increase in acute-phase reactants was detected during their disease episodes. The intensity of pain and fatigue was measured in AID patients and found to be high. A total of 88% of respondents received treatment again, while 8% reported no treatment.

CONCLUSIONS

AID patients, particularly adults, suffer from significant delays in diagnosis, misdiagnosis, and a variety of symptoms, including pain and fatigue. Based on the results presented, raising awareness of these diseases in the wider medical community is crucial to improving patient care and quality of life.

Immunologic and Genetic Contributors to CD46-Dependent Immune Dysregulation

Mutations in CD46 predispose to atypical hemolytic uremic syndrome (aHUS) with low penetrance. Factors driving immune-dysregulatory disease in individual mutation carriers have remained ill-understood. In addition to its role as a negative regulator of the complement system, CD46 modifies T cell-intrinsic metabolic adaptation and cytokine production. Comparative immunologic analysis of diseased vs. healthy CD46 mutation carriers has not been performed in detail yet. In this study, we comprehensively analyzed clinical, molecular, immune-phenotypic, cytokine secretion, immune-metabolic, and genetic profiles in healthy vs. diseased individuals carrying a rare, heterozygous CD46 mutation identified within a large single family. Five out of six studied individuals carried a CD46 gene splice-site mutation causing an in-frame deletion of 21 base pairs. One child suffered from aHUS and his paternal uncle manifested with adult-onset systemic lupus erythematosus (SLE). Three mutation carriers had no clinical evidence of CD46-related disease to date. CD4+ T cell-intrinsic CD46 expression was uniformly 50%-reduced but was comparable in diseased vs. healthy mutation carriers. Reconstitution experiments defined the 21-base pair-deleted CD46 variant as intracellularly-but not surface-expressed and haploinsufficient. Both healthy and diseased mutation carriers displayed reduced CD46-dependent T cell mitochondrial adaptation. Diseased mutation carriers had lower peripheral regulatory T cell (Treg) frequencies and carried potentially epistatic, private rare variants in other inborn errors of immunity (IEI)-associated proinflammatory genes, not found in healthy mutation carriers. In conclusion, low Treg and rare non-CD46 immune-gene variants may contribute to clinically manifest CD46 haploinsufficiency-associated immune-dysregulation.

IL-1 and autoinflammatory disease: biology, pathogenesis and therapeutic targeting

Over 20 years ago, it was first proposed that autoinflammation underpins a handful of rare monogenic disorders characterized by recurrent fever and systemic inflammation. The subsequent identification of novel, causative genes directly led to a better understanding of how the innate immune system is regulated under normal conditions, as well as its dysregulation associated with pathogenic mutations. Early on, IL-1 emerged as a central mediator for these diseases, based on data derived from patient cells, mutant mouse models and definitive clinical responses to IL-1 targeted therapy. Since that time, our understanding of the mechanisms of autoinflammation has expanded beyond IL-1 to additional innate immune processes. However, the number and complexity of IL-1-mediated autoinflammatory diseases has also multiplied to include additional monogenic syndromes with expanded genotypes and phenotypes, as well as more common polygenic disorders seen frequently by the practising clinician. In order to increase physician awareness and update rheumatologists who are likely to encounter these patients, this review discusses the general pathophysiological concepts of IL-1-mediated autoinflammation, the epidemiological and clinical features of specific diseases, diagnostic challenges and approaches, and current and future perspectives for therapy.

MEFV gene allele frequency and genotype distribution in 3230 patients' analyses by next generation sequencing methods

Familial Mediterranean Fever (FMF, OMIM ID: 249100) is the most common autoinflammatory, autosomal recessive disease caused by mutations in the MEFV gene. It is widespread in the Mediterranean, primarily among Turkish, Armenian, Arab and Jewish. This study aims to examine genotype distributions of common MEFV variants in the Turkish population using targeted NGS and to evaluate all rare mutations. It included 3230 people applying to Ege University Children's Hospital Molecular Medicine Laboratory with the suspicion of autoinflammatory disease between 2017 and 2021. MEFV missense variant was detected in 1839 (56.9%) individuals. One or more mutations were found in them. 1063 patients were heterozygous (57.8%), 410 were compound heterozygous (22.3%), 238 were complex genotype (12.9%), and 128 were homozygous (7%). 56 different mutations and 141 genotypes were detected, two of which were novel (p.His87Arg, c.260A > G and p.Leu396Phe, c.1186C > T). These were determined as 6benign, 40 uncertain significant, 3 likely pathogenic and 7 pathogenic according to the ACMG classification. The most common ones were R202Q (n = 1097, 37.48%), E148Q (n = 512, 17.49%), M694V (n = 493, 16.84%), V726A (n = 155, 5.30%), M680I (n = 150, 5.12%), P369S (n = 108, 3.69%), R408Q (n = 95, 3.25%) respectively. They constitute 89.17 % of the entire patient population. In conclusion, DNA variants/mutations in the MEFV gene were evaluated in 3230 patients. To date, no mutation screening has been encountered in such a large population using NGS. Genotype distributions of both common and rare mutations were revealed. The obtained data will hopefully contribute to the future genotype-phenotype studies of FMF disease.

Familial Mediterranean Fever: How to Interpret Genetic Results? How to Treat? A Quarter of a Century After the Association with the Mefv Gene

PURPOSE OF REVIEW

To provide an up-to-date approach to diagnosis and management of FMF patients.

RECENT FINDINGS

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease and prototype monogenic autoinflammatory recurrent fever syndrome. Although it is one of the well-known autoinflammatory disorders, evaluations in the etiopathogenesis and genetics of the disease have shown that FMF is more complex than previously known. Since the number of reported MEFV variants increased, evaluating the genetic test results has become more challenging. Here, we suggest a roadmap for clinicians to facilitate their decisions regarding diagnosis, treatment, and follow-up in FMF patients with different genotype-phenotype combinations. The correct interpretation of genetic test results is crucial for timely diagnosis, appropriate treatment, and follow-up of FMF patients.

The clinical effect of gene mutations in familial Mediterranean fever disease

BACKGROUND

Familial Mediterranean fever (FMF) is a self-limiting, autoinflammatory disease characterized by inflammation of the serosal surfaces and recurrent episodes of fever. The aim of this study is to determine the effect of genetic mutations on clinical features in children with FMF.

METHODS

A total of 303 patients aged 0-18 years, who were diagnosed with FMF, according to Yalcinkaya-Özen diagnostic criteria and whose Mediterranean fever gene (MEFV) analysis was studied, were evaluated retrospectively. The clinical and demographic characteristics of the patients and the relationship between common alleles and genotypes were investigated.

RESULTS

The most common mutation in patients was M694V heterozygous. When the patients were divided into four groups, M694V homozygous, M694V heterozygous, M694V/other allele combined heterozygous, and other mutations, Arthritis was statistically significantly higher in the group that was M694V homozygous compared to the other groups. It was observed that the presence of the M694V allele significantly increased the frequency of periodic fever, aphthous stomatitis, pharyngitis, adenitis syndrome. The frequency of arthritis was significantly higher in patients who were E148Q homozygous than in patients who were heterozygous. Appendectomy history was significantly higher in the group carrying the V726A allele.

CONCLUSIONS

FMF disease and the effect of genetics on the disease can be better understood, thanks to studies evaluating the genotype-phenotype relationship. In this regard, we believe that studies evaluating the clinical and genotype relationship with a large series are needed.

Role of E148Q in familial Mediterranean fever with an exon 10 mutation in MEFV

BACKGROUND

Familial Mediterranean fever (FMF) is an autosomal recessive disease caused by mutations in the MEFV gene. Mutations in exon 10 are associated with typical FMF. Most Japanese patients with typical FMF are compound heterozygotes of M694I in exon 10 and E148Q in exon 2. However, the pathogenic role of E148Q remains controversial.

METHODS

We assessed symptoms and serum cytokines among patients with FMF and their family members. They were divided into three subgroups, based on MEFV mutations: individuals carrying M694I and E148Q (group A, n = 14), individuals carrying M694I, but not E148Q (group B, n = 10), and individuals carrying E148Q, but not M694I (group C, n = 11).

RESULTS

All but one individual in group A had typical FMF phenotypes, whereas no individual in groups B and C exhibited any episodes of fever or serositis. The serum levels of interleukin-18 during the afebrile phase were significantly elevated in group A (2,806 ± 2,107 pg/mL), compared to those in groups B (499 ± 369 pg/mL) and C (427 ± 410 pg/mL). No difference in interleukin-6 levels was observed among the three groups.

CONCLUSIONS

These findings indicated that E148Q may contribute to disease development of FMF in Japanese patients carrying the heterozygous M694I mutation in MEFV and that genetic testing of both parents would lead to better counseling for their children.

Clinical significance of E148Q heterozygous variant in paediatric familial Mediterranean fever

OBJECTIVES

FMF results from mutations in the Mediterranean fever (MEFV) gene. The p. E148Q protein alternation is one of the most frequent in the MEFV gene, yet the exact E148Q genotype-phenotype correlation remains unclear. The aim of this study was to examine clinical significance of heterozygous E148Q variant in a paediatric FMF cohort.

METHODS

We compared the clinical manifestations and disease severity score of four genetic subgroups: (group 1) patients harbouring a single heterozygous p. E148Q variant (n = 6); (group 2) patients harbouring a single p. M694V heterozygous variant (n = 88); (group 3) patients harbouring compound heterozygous p. M694V and p. E148Q variants (n = 36); and (group 4) homozygotes for p. M694V variant (n = 160).

RESULTS

Of 646 FMF children from our centre, only 1% (six patients) of our genetically characterized FMF cohort had a single E148Q variant, most presenting with recurrent fevers and abdominal pain. None of the participants was found to harbour homozygous E148Q. Overall, M694V/E148Q compound heterozygosity did not exhibit a more severe phenotype compared with patients with a single M694V variant. The former group were less likely to have abdominal pain and exertional leg pain (P < 0.004 and P < 0.001, respectively) and more likely to have chest pain (P < 0.01). Both subgroups showed milder clinical phenotype compared with patients with M694V homozygosity.

CONCLUSION

Our findings demonstrate that a single heterozygous E148Q variant is unlikely to cause FMF in children and that E148Q/M694V is clinically indistinguishable from a single M694V variant. Thus, E148Q heterozygosity does not result in clinically meaningful phenotype in children.

Evaluation of E148Q and Concomitant AA Amyloidosis in Patients with Familial Mediterranean Fever

The aim of the study was to compare the clinical phenotype of patients with familial Mediterranean fever (FMF)-related AA amyloidosis, according to the age of FMF diagnosis and E148Q genotype. Patients with biopsy-confirmed FMF-related AA amyloidosis were included in the study. Tel-Hashomer criteria were applied in the diagnosis of FMF. All patients had detailed baseline assessment of clinical features, renal functions, genetic testing, histopathological diagnosis of amyloidosis, and treatment received. Multiple comparisons were performed according to the age of diagnosis, disease phenotype, mutation, and mortality. Our study included 169 patients with a diagnosis of AA amyloidosis. There were 101 patients diagnosed with FMF < 18 years of age and 68 patients diagnosed who were ≥18 years of age. The three most common clinical manifestations were fever (84.6%), abdominal pain (71.6%), and arthritis (66.9%). The most common allele among FMF patients was M694V (60.6%), followed by E148Q (21.4%), and M680I (10.3%). The most frequent genotypes were M694V/M694V (45.0%), M694V/E148Q (14.8%), and E148Q/E148Q (11.2%) among 169 patients in our cohort. During the follow-up period, 15 patients (10 male, 5 female) died, of whom 14 had M694V homozygous genotype and one was homozygous for E148Q. Clinicians should be aware of patients with homozygous E148Q genotype for close monitoring and further evaluation. The possible relationship between E148Q and AA amyloidosis needs to be confirmed in other ethnicities.

Comparison of Pediatric Familial Mediterranean Fever Patients Carrying Only E148Q Variant With the Ones Carrying Homozygous Pathogenic Mutations

OBJECTIVE

The aims of this study were to compare demographic data, clinical features, and severity scores of familial Mediterranean fever patients carrying E148Q variant with the patients having homozygous pathogenic MEFV mutations and to evaluate both of these groups for the performance of Tel-Hashomer, Livneh, and pediatric diagnostic criteria.

METHODS

The demographic and clinical data of patients with familial Mediterranean fever either heterozygous or homozygous for E148Q variant (group 1) and patients with homozygous mutations (M694V, M694I, M680I, V726A) (group 2) were collected retrospectively. All patients were evaluated for 3 diagnostic criteria.

RESULTS

E148Q variant was present in 128 patients (22.9%), 112 of whom had heterozygous and 16 of whom had homozygous E148Q mutation. Group 2 had 430 patients (77.1%), 372 of whom had homozygous M694V mutation, 50 of whom had homozygous M680I mutation, 5 of whom had homozygous V726A mutation, and 3 of whom had homozygous M694I mutation. Pleuritis, arthritis, recurrent fever, erysipelas-like erythema, and anemia were significantly more common in group 2 than group 1 (p < 0.05). Moderate and severe Pras scores were significantly higher in group 2 (p < 0.001). During attack-free periods, C-reactive protein, erythrocyte sedimentation rate, and serum amyloid A were found significantly higher in group 2 than in group 1 (p < 0.05). The percentage of children diagnosed according to Tel-Hashomer and pediatric criteria was significantly higher in group 2 than in group 1 (p < 0.05). Both groups show similar diagnostic utility by Livneh criteria.

CONCLUSIONS

Children with the E148Q variant met the 3 diagnostic criteria; they had a milder disease course both clinically and in laboratory means.

Dermatomyositis-like eruptions and fasciitis with novel compound heterozygous MEFV mutations: Newly recognized features of a variant of familial Mediterranean fever

Familial Mediterranean fever (FMF) is an autoinflammatory disease characterized by recurrent febrile attacks and serositis. The diagnosis of FMF has been based on clinical criteria, including frequent symptoms and good response to the treatment with colchicine. Some patients with FMF show skin or muscle manifestations, which may be confused with other cutaneous or muscle disorders. Here we report a female in her 40s with periodic fever, migratory myalgia, dermatomyositis-like dermatitis, arthralgia, pharyngalgia, and lymphadenopathy. The initial clinical differential diagnosis included dermatomyositis, malignant lymphoma, and adult-onset Still's disease. However, the following examinations could not explain her pathological condition with such diseases. In particular, findings from muscle and fascial biopsy demonstrated severe inflammatory cell infiltrate in the fascia, suggesting fasciitis as a possible cause of migratory myalgia. We examined the possibility of autoinflammatory diseases by genetic testing. Accordingly, she was found to have novel compound heterozygous mutations (L110P, E148Q, and P369S) in the MEFV gene. Given her genetic mutations and favorable response to colchicine, she was finally diagnosed as a variant of FMF with myalgia and previously unprecedented skin eruptions.

MEFV E148Q variant is more associated with familial Mediterranean fever when combined with other non-exon 10 MEFV variants in Japanese patients with recurrent fever

OBJECTIVE

To investigate the genetic characteristics of one of the MEFV gene variants, p.Glu148Gln (E148Q), in patients with familial Mediterranean fever (FMF) and examine its significance in Japanese patients with recurrent fever.

METHODS

The clinical phenotype and genomic variants of systemic autoinflammatory diseases (SAIDs), including MEFV, were analyzed in 211 Japanese patients with recurrent fever. Genetic analysis was performed via next-generation sequencing of exons, including exon-intron boundaries.

RESULTS

Twelve patients met the diagnostic criteria for SAIDs other than FMF. Considering 199 patients with recurrent fever, 137 cases (68.8%) were clinically diagnosed with FMF. Although Bonferroni-adjusted p-value did not reach significance level, the group containing heterozygous E148Q and other variants tended to be at higher risk of developing the FMF phenotype (nominal p = .036) than the group with heterozygous E148Q only. Comparison between the group with heterozygous E148Q and other variants and the heterozygous group containing non-E148Q showed no statistically significant difference in FMF phenotype expression (nominal p = 1.00).

CONCLUSION

Patients with heterozygous E148Q and other variants exhibited higher expression of FMF phenotype than those with heterozygous E148Q only, and suggested that other variants than E148Q as well as exon 10 variants might contribute to the FMF phenotype.

Comparison of Clinical and Demographic Features of FMF with Sacroiliitis Patients with FMF and Axial Spondyloarthritis Patients

Objectives Familial Mediterranean fever (FMF) is the most common autoinflammatory disease, characterised by recurrent fever and serositis attacks lasting 1–3 days. Musculoskeletal involvement is the second most common manifestation in FMF patients. Sacroiliitis is another musculoskeletal involvement; as there is no spinal involvement, this is called FMF with sacroiliitis. This study was designed to investigate the clinical, demographic and genetic features of FMF in sacroiliitis patients and to compare them with axial SpA and FMF patients.

Materials and Methods Forty-two FMF with sacroiliitis patients, 100 axial SpA patients and 100 FMF patients were recruited, and their demographic characteristics were recorded. Evidence of sacroiliitis was confirmed by sacroiliac joint MRI, and patients were examined for arthritis and enthesitis. MEFV gene mutations, HLA B27 positivity and ESR and CRP results were compared.

Results In the FMF with sacroiliitis group, the M694V mutation was detected in 59.5% of patients. FMF with sacroiliitis patients were largely (83.3%) negative for HLA B27. The frequency of enthesitis was similar between FMF with sacroiliitis and axial SpA, and the frequency of arthritis was higher in axial SpA patients. Inflammatory markers (ESR and CRP) were statistically higher in FMF with sacroiliitis patients compared with axial SpA and FMF patients.

Conclusion When all three groups were compared, the M694V mutation was more common, HLA B27 was largely negative and inflammatory markers were higher in the FMF with sacroiliitis group. FMF should be included in the differential diagnosis of sacroiliitis for managing treatment correctly and preventing complications.

Clinical phenotypes and genetic analyses for diagnosis of systemic autoinflammatory diseases in adult patients with unexplained fever

OBJECTIVE

To make an accurate diagnosis of systemic autoinflammatory diseases (SAIDs), clinical and genetic analyses were performed in patients with unexplained fever.

METHODS

The clinical phenotype and genomic variants of 11 genes responsible for SAIDs were analyzed in 179 Japanese patients with unexplained fever. Genetic analysis was performed by next generation sequencing (NGS) on exons including exon-intron boundaries.

RESULTS

Three cases met the diagnostic criteria for SAIDs other than familial Mediterranean fever (FMF). Considering 176 patients with unexplained fever, 43 cases (24.0%) were clinically diagnosed as FMF. Gene variants were found in 53 cases (30.1%) when searching for variants in the 10 disease genes other than the MEFV gene. Among them, the most frequently-identified genes were NLRP3, NOD2, NLRP12, NLRC4, and PLCG2, which accounted for 14, 7, 17, 7, and 6 cases, respectively. These variants were less than 1% of healthy individuals or novel variants, but not regarded as pathogenic since the patients did not meet the diagnostic criteria of SAIDs caused by their identified variants clinically.

CONCLUSION

Twenty four percent of Japanese patients with unexplained fever were clinically diagnosed as FMF in this study. Low frequency but not pathogenic variants in genes other than MEFV were identified in 30.1% of the cases. It is not clear how much these gene variants contribute to the inflammatory phenotypes; therefore, further analysis would uncover their autoinflammatory phenotypes that cause fever.

Amyloid A amyloidosis in a patient with Caplan's syndrome, with special reference to genetic predisposition

Secondary amyloid A (AA) amyloidosis, which is a disorder of protein conformation and metabolism, is an important serious complication of inflammatory diseases, especially rheumatoid arthritis (RA). AA amyloidosis develops when AA fibrils, which are derived from the acute-phase reactant, serum amyloid AA (SAA) protein, in the circulation, are deposited in organs and cause systemic organ dysfunction. Caplan's syndrome, or rheumatoid pneumoconiosis, is a rare type of lung disease in which individuals suffering from RA develop lung nodules that are associated with occupational exposure to silica and coal dust. Confirmation of diagnosing as Caplan's syndrome requires the patient's occupational history, imaging studies, and serology. A 72-year-old male, working as a tunnel construction worker for 38 years, with RA who had both chronic cardiac and renal dysfunction was referred to our hospital. He received a diagnosis of pneumoconiosis about 20 years ago, after which he was also diagnosed with RA. So far we performed medical English literature searches on the combination of Caplan's syndrome with AA amyloidosis; there were no articles in relation to such association. Although RA is one of the most common underlying diseases that occur with AA amyloidosis, our report here is the first description of a case of Caplan's syndrome associated with AA amyloidosis. In this report, we provide details about this rare disease occurring with AA amyloidosis and discuss on the possible pathogenesis of AA amyloidosis from a genetic point of aetiological view.

Characteristics of patients with familial Mediterranean fever in Denmark: a retrospective nationwide register-based cohort study

Objectives: To investigate epidemiology, demography, and genetic and clinical characteristics of patients with familial Mediterranean fever (FMF) in Denmark. Method: In this population-based, cross-sectional cohort study, we identified FMF patients from discharge diagnoses using ICD-10 codes in the Danish National Patient Register, and linked data from the Danish Civil Registration System and laboratory databases for results of MEFV gene variant screening. Results: We identified 495 FMF patients (prevalence 1:11 680) with a median age of 29 years and a female ratio of 51%. The median age at diagnosis of FMF was 13 (IQR 7-22) years, with an estimated median diagnostic delay of 3 (IQR 0.7-6.9) years. The predominant ethnicities were Turkish (41.8%), Lebanese (15.8%), Syrian (6.5%), South-West Asian (7.9%), and South-East Asian (3.0%). The MEFV genotype distribution was 18.7% homozygous, 21.2% compound heterozygous, 32.0% heterozygous, 11.0% with complex alleles or unresolved zygosity, and 17.1% with no detected variants. M694V was the most prevalent variant in the overall cohort (32.5%). Homozygous or compound heterozygous MEFV exon 10 variants were associated with younger age at diagnosis (p < 0.001) and reduced number of hospital contacts before diagnosis (p = 0.008). The Charlson Comorbidity Index was ≥ 2 in 8.1% of patients. The prevalence of amyloidosis was 1.0%. Conclusions: FMF in Denmark is rare and patients are mainly of Eastern Mediterranean ethnicity. Diagnostic delay was long but patients with exon 10 MEFV variants were diagnosed at a younger age. Prolonged diagnostic delay is probably caused by lack of FMF awareness in the Danish healthcare system.

Coexisting Diseases in Patients with Familial Mediterranean Fever

Background and Aims

Familial Mediterranean fever (FMF) is a prototype of autoinflammatory disease and mainly associated with MEFV gene mutations. This single-center study as an experience represents FMF-coexisting disease in the FMF registration database.

Methods

Four hundred patients who had FMF based on clinical criteria (Tel-Hashomer) and/or MEFV mutations enrolled the study. Twelve most common MEFV mutations (P369S, F479L, M680I (G/C), M680I (G/A), I692del, M694V, M694I, K695R, V726A, A744S, R761H, E148Q) were analyzed if needed by the reverse hybridization assay. Any co-existed disease had been confirmed by a related subspecialist. All data were analyzed by a simple analytical method.

Results

Fifty-seven (14%) patients had associated disease, 32 patients were male and 24 patients were under 10 years old. They included 92 MEFV variant alleles and only in five patients there were not any mutations. The most common variant alleles were M694V (36%), E148Q (22%), V726A (17%), M680I (1%) and M694I (0.07%) respectively. Rheumatologic disorders were the most common coexisting disease, then followed by gastrointestinal and neurological disorders. Some rare diseases such as TTP, growth hormone deficiency, multiple sclerosis, idiopathic ascites, Leiden factor V deficiency and Felty syndrome have been detected. Homozygote mutations of (M694V-M694V) were associated with idiopathic ascites, orchitis and pericarditis.

Conclusion

Coexisting disease in patients with FMF is presented with positive MEFV gene mutations particularly with these five common variant alleles: M694V, E148Q, V726A, M680I, and M694I. The commonly associated diseases are rheumatologic, gastrointestinal and CNS disorders.

Current State of Precision Medicine in Primary Systemic Vasculitides

Precision medicine (PM) is an emerging data-driven health care approach that integrates phenotypic, genomic, epigenetic, and environmental factors unique to an individual. The goal of PM is to facilitate diagnosis, predict effective therapy, and avoid adverse reactions specific for each patient. The forefront of PM is in oncology; nonetheless, it is developing in other fields of medicine, including rheumatology. Recent studies on elucidating the genetic architecture of polygenic and monogenic rheumatological diseases have made PM possible by enabling physicians to customize medical treatment through the incorporation of clinical features and genetic data. For complex inflammatory disorders, the prevailing paradigm is that disease susceptibility is due to additive effects of common reduced-penetrance gene variants and environmental factors. Efforts have been made to calculate cumulative genetic risk score (GRS) and to relate specific susceptibility alleles for use of target therapies. The discovery of rare patients with single-gene high-penetrance mutations informed our understanding of pathways driving systemic inflammation. Here, we review the advances in practicing PM in patients with primary systemic vasculitides (PSVs). We summarize recent genetic studies and discuss current knowledge on the contribution of epigenetic factors and extracellular vesicles (EVs) in disease progression and treatment response. Implementation of PM in PSVs is a developing field that will require analysis of a large cohort of patients to validate data from genomics, transcriptomics, metabolomics, proteomics, and epigenomics studies for accurate disease profiling. This multi-omics approach to study disease pathogeneses should ultimately provide a powerful tool for stratification of patients to receive tailored optimal therapies and for monitoring their disease activity.

Familial mediterranean fever: assessment of clinical manifestations, pregnancy, genetic mutational analyses, and disease severity in a national cohort

The aims of this study were to investigate the main clinical and laboratory features, including pregnancy and genetic analysis, of Turkish Familial Mediterranean Fever (FMF) patients and to analyze the relationships between genotypic features, age of disease onset, clinical findings, and disease severity. A study was planned within a national network of 22 different centers. Demographics, clinical and laboratory findings, attack characteristics, drugs, pregnancy and birth history, disease severity, and gene mutation analyses were evaluated. Disease severity, assessed using a scoring system developed by Pras et al., was evaluated in relation to gene mutations and age of disease onset. A total of 979 patients (643 females and 336 males; mean age: 35.92 ± 11.97 years) with FMF were included in the study. Of a total of 585 pregnancies, 7% of them resulted in preterm birth and 18.1% resulted in abortions. During pregnancy, there was no FMF attack in 61.4% of patients. Of the MEditerranean FeVer (MEFV) mutations, 150 (24.3%) cases were homozygous, 292 (47.3%) cases were heterozygous, and 175 (28.4%) were compound heterozygous. Patients with homozygous gene mutations had more severe disease activity, earlier age of disease onset, higher rates of joint and skin involvement, sacroiliitis, and amyloidosis. Patients with compound heterozygous genotype displayed severe disease activity in close resemblance to patients with homozygous mutation. In addition, patients with compound heterozygous mutations had higher rates of protracted febrile myalgia and elevated fibrinogen levels. In 63.9% of compound heterozygous patients, age of onset was < 20 years, with greater disease severity, and high rates of attack frequency and colchicine resistance. Our results suggest that indicators for disease severity include early onset of disease and homozygous gene mutations. Furthermore, patients with compound heterozygous mutations displayed significant presentations of severe disease activity.

Mediterranean fever (MEFV) gene profile and a novel missense mutation (P313H) in Iranian Azari-Turkish patients

BACKGROUND

Familial Mediterranean fever (FMF) is common in Azari-Turkish people, one of the biggest ethnic groups in Iran. In this study, we sought to investigate the mutation spectrum of the MEFV gene and any genotype-phenotype correlations.

METHODS AND MATERIALS

400 unrelated Azari-Turkish FMF patients were analyzed in this study. Mutations in exons 2, 3, 5, and 10 of the MEFV gene were investigated using direct Sanger sequencing, and their correlations with the clinical features of the patients were analyzed.

RESULTS

At least one mutation was detected in 248 (62%) patients. The most common mutations were M694V (26.25%) and E148Q (24.75%), respectively. Abdominal pain (65.2%) and fever 204 (51%) were the most frequent clinical problems in all subjects. The analysis recognized a novel missense mutation in the coding region of the MEFV gene, named P313H, which is the first report of a new mutation in exon 2 of the MEFV gene in an Azari-Turkish family.

CONCLUSION

Genotype-phenotype correlations obtained from this study would be helpful in the diagnosis and management of FMF patients in clinical situations. This novel missense mutation may provide useful evidence for further studies of FMF pathogenesis.

Periodic fever syndromes: beyond the single gene paradigm

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease in Canada and is characterized by a clinical syndrome of episodic inflammatory symptoms. Traditionally, the disease is defined by autosomal recessive inheritance of MEFV gene variants, yet FMF also not uncommonly manifests in individuals with only one identified disease-associated allele. Increasing availability and affordability of gene sequencing has led to the identification of multiple MEFV variants; however, they are often of unknown clinical significance. Variants in other genes affecting overlapping or distinct inflammatory signaling pathways - together with gene-environment interactions including epigenetic modulation - likely underlie the significant genetic and phenotypic heterogeneity seen among patients with this disease. We review recent evidence of the expanding spectrum of FMF genotype and phenotype and suggest that current drug funding schemes restricting biologic agents to patients with homozygous mutations have not kept pace with our biological understanding of the disease.

A Rare Case of Cryopyrin-associated Periodic Syndrome in an Elderly Woman with NLRP3 and MEFV Mutations

We herein report a case of a 75-year-old woman who presented with a low-grade fever, repeated cold-induced urticaria, and painful leg edemas with neutrocytosis. Because her mother also had cold-induced urticaria and her skin lesions histologically showed neutrophilic dermatitis, we suspected that she had familial cold autoinflammatory syndrome, a subtype of cryopyrin-associated periodic syndromes. Sequencing of the NLRP3 and MEFV genes revealed that she carried both the p.A439V missense mutation and p.E148Q homozygous mutation, which is commonly detected in familial Mediterranean fever patients. The administration of colchicine reduced the frequency and severity of her skin rash and leg edema.

Association of pyrin mutations and autoinflammation with complex phenotype hidradenitis suppurativa: a case-control study

BACKGROUND

Hidradenitis suppurativa (HS) is a rare, debilitating neutrophilic dermatosis characterized by chronic inflammation of hair follicles. Many inflammatory conditions may accompany HS.

OBJECTIVES

To investigate the association of variants of the MEFV gene with a complex HS phenotype.

METHODS

Firstly, we identified the clinical characteristics of 119 patients with HS with a complex phenotype (Hurley stage III disease and/or additional inflammatory symptoms). Then, we searched for MEFV variants among these patients. The odds ratios (ORs) for pathogenic MEFV mutations were calculated using data from these patients with HS and 191 healthy controls.

RESULTS

The male/female ratio was higher, and the mean age of onset was earlier, in our complex HS group compared with patients with HS in general. Five of the patients with HS (4·2%) had a diagnosis of familial Mediterranean fever (FMF) with a standardized morbidity ratio of 45 [95% confidence interval (CI) 16·50-99·84, P < 0·001] when compared with the frequency of FMF in the general Turkish population. Of the patients with complex HS, 38% were positive for pathogenic variants of MEFV. The OR for carrying a pathogenic MEFV allele was 2·80 (95% CI 1·31-5·97, P < 0·001).

CONCLUSIONS

The frequency of MEFV mutations in the group of patients with complex HS was higher than that in healthy controls, suggesting that MEFV mutations may contribute to the pathogenesis of HS. Understanding the role of autoinflammation in HS is of fundamental importance for the development of novel therapies.

Familial Mediterranean Fever

Familial Mediterranean Fever (FMF) is the oldest and the most frequent of all described hereditary periodic fever syndromes. The populations originating from Mediterranean basin carry the highest risk for FMF however it is being increasingly recognized in many parts of the world. It is an autoinflammatory disease with an autosomal recessive transmission. In the majority of the patients it is related with mutations in the MEFV gene that encodes a protein named pyrin. This protein has been shown to act as a regulator of inflammation mediated by IL-1β, which plays a major role in the pathogenesis of FMF. Approximately one-third of the patients have either a single or no mutation which raise questions about its mode of inheritance. FMF is a clinical diagnosis and characterized by self-limited bouts of fever and serositis. The main long-term complication of the disease is AA amyloidosis. The mainstay of treatment is life-long colchicine given daily to prevent the recurrence of febrile attacks and the development of amyloidosis. Patients with insufficient response to colchicine may be treated with anti IL-1 agents.

Novel presentations of periodic fever syndromes: Discrepancies between genetic and clinical diagnoses

Objective

The Periodic fever syndromes (PFS) are a group of disorders of the innate immune system. We investigated patients diagnosed with PFS at the Dartmouth Hitchcock Pediatric Rheumatology Clinic.

Methods

Case acquisition was performed by reviewing ICD 9/10 coded records for familial Mediterranean fever (ICD 9 277.31), laboratory test records for PFS genetic screening, and clinic records between 1/1/2011 and 12/31/2017.

Results

Twenty-seven cases had clinical evaluations including PFS genetic screening. Clinical diagnoses included familial Mediterranean fever (FMF) (10 cases), Muckle-Wells (2 cases), tumor necrosis factor receptor associated periodic syndrome (TRAPS) (4 cases), hyper IgD syndrome (HIDS) (1 case), Crohn’s Disease (1 case), systemic onset juvenile idiopathic arthritis (SoJIA) (1 case), fever of unknown origin (FUO) (1 case), periodic fever adenitis pharyngitis aphthous ulcer (PFAPA) (6 cases), and cold-induced urticaria (1 case). Fifteen cases were associated with a genetic cause. Seven of the 10 FMF cases were confirmed genetically and were either heterozygous or compound heterozygotes. Both cases of Muckle-Wells had either a compound heterozygote for CIAS 1 or a NOD gene mutation. Both TRAPS cases presented atypically with patients developing systemic lupus erythematosus (SLE) or being asymptomatic. Two patients had novel syndromes. One FMF patient had a TRNT1 gene mutation who responded to intravenous immunoglobulin (IVIg) and colchicine after failing multiple treatments. The other had SoJIA with a LPIN 2 gene mutation but responded to colchicine. Only one of the 15 genetically proven cases had classical presentation and genetics (HIDS secondary to a mevalonate kinase (MVK) gene mutation).

Conclusion

PFS screening was helpful in over half of the cases to develop therapeutic treatment plans. Given the atypical clinical presentations seen with genetically determined PFS, extensive genetic testing is indicated for all patients presenting with a PFS, excluding classical PFAPA syndrome.

Familial Mediterranean Fever Mutations in a Patient with Periodic Episodes of Systemic Pain Deriving from Cancer Bone Metastases

Familial Mediterranean fever (FMF), the most common autoinflammatory disorder, is characterized by recurrent febrile attacks and polyserositis. FMF is caused by mutations in MEFV, which encodes pyrin. In this report, we present an atypical FMF case with E148Q/L110P mutations in MEFV. The patient experienced periodic episodes of systemic pain originating from prostate cancer bone metastases. The pain attacks were prevented by continuous prophylactic therapy with colchicine. In this case, the presence of atypical FMF may have modulated the clinical manifestations of cancer bone metastases. To our knowledge, this is the first report to demonstrate the potential modulatory effect of MEFV mutations on cancer manifestations.

Familial Mediterranean Gene (MEFV) Mutation in Parents of Children with Familial Mediterranean Fever: What Are the Exceptions?

Objectives

Familial Mediterranean Fever (FMF) is one of the most prevalent periodic fever syndromes; MEFV, the responsible gene for the disease, is in the short arm of chromosome16. In the considerable count of the FMF patients, only one mutation is found in the MEFV and parents, who were the obligatory carriers for that mutation, were asymptomatic. The aim of this study was to evaluate these asymptomatic parents in regard to mutation in MEFV gene and similarity between parents and offspring patients.

Methods

In this cross-sectional study, asymptomatic parents of FMF patients enrolled the study were referred to periodic fever clinic or pediatric rheumatology clinic of Tehran University of Medical Sciences. The patients should have at least one mutation in MEFV gene and none of them had any family history of autoinflammatory disease. Twelve mutations in MEFV gene were assessed in the parents by Vienna Lab FMF Strip Assay kit by MAS PCR/Reverse hybridization.

Results

Forty-three patients and their parents participated in the study. Sixty-three percent (27) of patients were male. Onset of disease symptoms in 31 patients (72%) was before 4 years of old. Nine (21%) of the patients had homozygote, 16 (37%) compound heterozygote, and 17(40%) heterozygote for MEFV mutation; there was a case of complex alleles mutations (2%). M694V/M694V in 4 patients (9%) was the most homozygote genotype, and M694V/R761H in 4 (9%) and E148Q in 7 (16%) were the most compound heterozygote and heterozygote genotype, respectively. M694V, M680I, and E148Q were the most mutation in the parents. Overall, 41 patients had mutations similar to their parents' mutation, except 2 whose parents had no mutation, but a patient did.

Conclusion

It seems that occurrence of new mutations in offspring is not prevalent among FMF patients and there are other reasons for different clinical presentation in similar mutation carriers. On the other hand, in ethnicities with high prevalence of FMF, new mutation in descendant may occur, infrequently.

Kounis Syndrome, a Cause of Chest Pain to Keep in Mind, May be Associated with E148Q Mutation

Chest pain is among the leading complaints in paediatric emergency. The Kounis syndrome is a rare allergic coronary vasospasm, which can cause angina and myocardial infarction. Even though organic causes are infrequent as a cause of chest pain in children, it is important to know when and how this symptom may become serious. We reported a patient who had been admitted with chest pain to the emergency department, hospitalised for coronary vasospasm and diagnosed to have Kounis syndrome and heterozygous E148Q mutation. The finding could be a coincidental finding, but considering of the heterogeneity and phenotypic differences in FMF, the relationship between E148Q mutation and Kounis syndrome should be explored further.

Investigation of MEFV gene polymorphisms (G138G and A165A) in adult patients with familial Mediterranean fever

AIM

Various mutations have been identified in the Mediterranean fever (MEFV) gene which is reported to be responsible from Familial Mediterranean fever (FMF). In our study, we aimed to determine the frequency of the MEFV mutations in our region and to investigate the impact of G138G (rs224224, c.414A>G) and A165A (rs224223, c.495C>A) gene polymorphisms on the clinical findings of the disease.

METHODS

One hundred and sixteen patients diagnosed with FMF and 95 control subjects were included in this study. We used the DNA sequence analysis method to identify the most prevailing 10 mutations located in exon 2 and 10 of MEFV gene.

RESULTS

As a result of the MEFV mutation analysis, the most common mutation was the M694V mutation allele with a frequency rate of 41.8%. When the patients group and control group were compared in terms of frequency of both polymorphic alleles (G polymorphic allele, observed in G138G and the A polymorphic allele, observed in A165A), the variation was observed to be statistically significant (p<0.001). It was found that the MEFV mutation types have no relation with clinical findings and amyloidosis (p>0.05).

CONCLUSIONS

To our knowledge, our study is the first study in the Southern Marmara region that reports the frequency of MEFV mutations. Our findings imply that the polymorphisms of G138G and A165A may have an impact on progress of the disease. We think that more studies, having higher number of cases and investigating the polymorphisms of MEFV gene, are needed.

Vasculitis and vasculitis-like manifestations in monogenic autoinflammatory syndromes

Monogenic autoinflammatory syndromes are a rare group of disorders characterized by periodic episodes of systemic inflammation of endogenous origin. Sometimes, these diseases may present with features akin to vasculitis. We conducted a literature review on such vasculitic manifestations in described monogenic autoinflammatory syndromes utilizing the Online Mendelian Inheritance in Man (OMIM), Medline, and Scopus databases. Our search identified that Familial Mediterranean fever (FMF) can manifest with features of either small, medium, large, or variable-vessel vasculitis. Stimulator of interferon gene (STING)-associated vasculopathy of infancy (SAVI) is an interferonopathy that can mimic the presentation of medium-vessel or small-vessel vasculitis, whereas deficiency of adenosine deaminase 2 (DADA2) is another such mimic of medium-vessel vasculitis, associated in a significant number of patients with features of immunodeficiency. Occasional reports exist of vasculitic manifestations in tumor necrosis factor (TNF) receptor-associated periodic fever syndrome (TRAPS) and chronic infantile neurologic cutaneous and articular disorder (CINCA), whereas mevalonate kinase deficiency can also mimic the presentation of small- or medium-vessel vasculitis. Clinicians should be aware of the possibility of autoinflammatory disease presenting as vasculitis to diagnose and treat the same appropriately.

Familial Mediterranean Fever: Recent Developments in Pathogenesis and New Recommendations for Management

Familial Mediterranean fever (FMF) is the most common monogenic autoinflammatory disease (AID) affecting mainly the ethnic groups originating from Mediterranean basin. The disease is characterized by self-limited inflammatory attacks of fever and polyserositis along with elevated acute phase reactants. FMF is inherited autosomal recessively; however, a significant proportion of heterozygotes also express the phenotype. FMF is caused by mutations in the MEFV gene coding for pyrin, which is a component of inflammasome functioning in inflammatory response and production of interleukin-1β (IL-1β). Recent studies have shown that pyrin recognizes bacterial modifications in Rho GTPases, which results in inflammasome activation and increase in IL-1β. Pyrin does not directly recognize Rho modification but probably affected by Rho effector kinase, which is a downstream event in the actin cytoskeleton pathway. Recently, an international group of experts has published the recommendations for the management of FMF. Colchicine is the mainstay of FMF treatment, and its regular use prevents attacks and controls subclinical inflammation in the majority of patients. Furthermore, it decreases the long-term risk of amyloidosis. However, a minority of FMF patients fail to response or tolerate colchicine treatment. Anti-interleukin-1 drugs could be considered in these patients. One should keep in mind the possibility of non-compliance in colchicine-non-responders. Although FMF is a relatively well-described AID and almost 20 years has passed since the discovery of the MEFV gene, there are still a number of unsolved problems about it such as the exact mechanism of the disease, symptomatic heterozygotes and their treatment, and the optimal management of colchicine resistance.

The MEFV gene pathogenic variants and phenotype-genotype correlation in children with familial Mediterranean fever in the Çanakkale population

The aim of the current study was to determine the frequency of the Mediterranean fever (MEFV) gene pathogenic variants in 60 children diagnosed with familial Mediterranean fever (FMF) and to compare the phenotype-genotype correlation. Genomic DNA was isolated by the spin-column method from peripheral blood samples (collected in vacutainers containing EDTA) and buccal smears. The MEFV gene profiles for the current FMF cohort were genotyped by pyrosequencing and direct Sanger sequencing techniques for the target pathogenic variants. The most prominent clinical symptoms were abdominal pain (53.4%), fever (23.4%) and arthritis (23.3%). Eighteen different pathogenic variants were identified and the most frequent were p.Met694Val (20.0%), p.Glu148Gln (13.3%), p.Met680 Ile (11.7%) and p.Arg202Gln (11.7%). Abdominal pain, fever and arthritis were the most common presenting clinical characteristics. Results showed that not only clinical characteristics, but also genotyping of the MEFV gene is needed to establish the correct diagnosis of FMF in children and other family members.

Familial Mediterranean fever patients homozygous for E148Q variant may have milder disease

AIM

Familial Mediterranean fever (FMF) results from MEFV gene mutations. E148Q is a variant of unknown significance in MEFV. We aimed to define characteristics of FMF patients homozygous for E148Q, check for other MEFV variants in a subgroup, and compare the characteristics with FMF patients carrying other mutations.

METHODS

Thirty FMF patients homozygous for E148Q were reviewed. MEFV variant analysis was performed with strip assay. All MEFV exons were screened by direct DNA sequencing in 14 randomly selected E148Q/E148Q patients. E148Q was also checked in 100 healthy adolescents. We compared the characteristics of FMF patients between three groups: E148Q/E148Q (n = 30), M694V/E148Q (n = 19) and exon 10/exon 10 MEFV mutations (n = 48).

RESULTS

Among 30 FMF patients (E148Q/E148Q), the median age at disease onset and diagnosis were 60 (12-168) and 94 (41-196) months, respectively. Fifteen (50%) patients had mild, 14 (46.7%) moderate and one (3.3%) had severe disease. Twenty-two (73.3%) patients had complete, seven (23.3%) had incomplete response to colchicine, while only one was unresponsive. The detected MEFV variants in 14 E148Q/E148Q FMF patients were as follows: R314R (n = 9; 64.3%), E474E (n = 13; 92.9%), Q476Q (n = 13; 92.9%), D510D (n = 13; 92.9%), and P588P (n = 8; 57.1%). The E148Q allele frequency was 6.5% in healthy adolescents. When compared to FMF patients with other MEFV mutations, disease onset was later, disease was less severe and the ratio of patients responding completely to colchicine was higher in E148Q/E148Q patients.

CONCLUSION

Patients homozygous for E148Q and negative for other pathogenic MEFV variants may display FMF phenotype and may experience moderate/severe disease activity, although the disease may be milder when compared to FMF patients with other mutations.

Distribution of MEFV gene mutations and R202Q polymorphism in the Serbian population and their influence on oxidative stress and clinical manifestations of inflammation

BACKGROUND

The Mediterranean fever (MEFV) gene codes for protein pyrin, one of the regulators of inflammasome activity in innate immune cells. Mutations in this gene are considered the primary cause of Familial Mediterranean fever, but are also found in other monogenic and multifactorial autoinflammatory diseases. The aim of the study was to determine if healthy carriers of MEFV gene mutations and R202Q polymorphism have clinical manifestations of inflammation and impaired oxidative stress parameters.

METHODS

One hundred DNA samples from healthy volunteers (13.3 ± 8.87 years of age (mean ± SD); range 2-35) were sequenced by ABI PRISM 310 automated sequencer (PE Applied Biosystems, Norwalk, USA). The Eurofever questionnaire was used to collect retrospectively medical history data. Oxidative stress was determined by measuring spectrophotometrically thiobarbituric acid reactive substances (TBARS) in plasma and erythrocytes, as well as advanced oxidation protein products in plasma. Superoxide dismutase (SOD) activity was determined by McCord and Fridovich method in plasma and erythrocytes, while the catalase erythrocyte activity was assessed using a catalase ELISA kit.

RESULTS

We found heterozygous carriers of K695R/N mutations in 5 %, E148Q/N mutations in 6 %, R202Q homozygous polymorphism in 10 % and heterozygous R202Q alterations in 45 % of healthy volunteers. The MEFV mutation carriers and R202Q polymorphism homozygotes reported significantly more often recurrent febrile episodes (p = 0.009), diffuse abdominal pain (p = 0.025), and malaise (p = 0.012) compared to non-carriers. Erythrocyte TBARS levels and plasma SOD activity were higher in persons with MEFV mutations and R202Q/R202Q (p = 0.03 and p = 0.049, respectively).

CONCLUSIONS

Healthy individuals may bear E148Q and K695R MEFV gene mutations, as well as R202Q polymorphism in homozygous state. The determined gene alterations contribute to a subtle oxidative stress and may be associated with more frequent episodes of fever and unspecific inflammatory manifestations. An incomplete penetrance or variable expressivity of R202Q in populations of different ethnicity could influence the expression of autoinflammatory diseases phenotype.

A case report of cutaneous polyarteritis nodosa in siblings

Cutaneous polyarteritis nodosa (CPAN) is characterized by a necrotizing vasculitis of small and medium-sized arteries in the skin, which can be associated with fever, arthralgia, myalgia, and neuropathy, but, unlike polyarteritis nodosa (PAN), there is no visceral involvement. CPAN is rare in childhood. We report two siblings who developed CPAN during childhood. Interestingly, both had Mediterranean fever gene (MEFV) mutation, i.e. heterozygous E148Q. They also shared HLA-A24, -DR15 alleles. Simultaneous occurrence of MEFV mutation and HLA alleles with CPAN has never been reported in Japan. These cases could provide some hereditary clue for the development of CPAN.

Could familial Mediterranean fever gene mutations be related to PFAPA syndrome?

BACKGROUND

The cause and pathophysiology of PFAPA syndrome is unknown. The aim of this study was to determine all MEFV gene variants relevant to familial Mediterranean fever in children with PFAPA syndrome.

METHODS

All MEFV gene variants were analyzed in patients with PFAPA syndrome. All patients were evaluated using the Gaslini scoring system. Serum immunoglobulin levels were also determined upon admission.

RESULTS

We evaluated 64 patients with PFAPA syndrome. The median age at diagnosis was 37.5 (min-max: 6-96) months, and the percentage of male patients was 55.0%. The Gaslini diagnostic score for periodic fever was high in 81.0% of the patients. An MEFV gene mutation was found in 42 (66.0%) children. Mostly, heterozygous or compound heterozygous variants of the MEFV gene were found. Two patients were homozygous for R202Q. MEFV gene mutations were not detected in 22 (34.0%) patients. No significant differences in clinical or laboratory findings were observed between the two groups (p > 0.05), and there were no significant differences in period and duration of the fever episodes (p > 0.05). The fever of all 47 patients (100.0%) who received prednisolone during the episodes decreased within hours and did not recur. Eighteen of the patients using prednisolone underwent prophylaxis with colchicine, and the fever episodes of 9/18 (50.0%) patients using colchicine decreased within months.

CONCLUSIONS

Most patients presenting with PFAPA syndrome have heterozygous MEFV gene mutations. Whether carrying a heterozygous MEFV gene is the primary cause of this syndrome requires further investigation.

Relationship between clinical findings and genetic mutations in patients with familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is one of the most frequent genetic diseases encountered in the Mediterranean region. We aimed to investigate the correlation between genetic mutations and the clinical findings in 562 patients with FMF.

METHODS

In this retrospective cross-sectional study conducted with patients' files between 2006, and 2013, reverse hybridization assay for MEFV gene mutations was used and the 12 most frequent mutations were screened. Mutation types and clinical findings were compared with variance analysis.

RESULTS

The mean age was 6.9 ± 3.4 years (range, 1.8-11.6 years). The most common symptom was fever (97.3%). Thirty-four of the patients (6.04%) were admitted with periodic fever only. Of these patients, M694V was the most common mutation type (73.5%). The percentage of the patients predominantly presenting with recurrent abdominal pain was 77.78% and the most frequent mutations were M694V and E148Q. The rate of arthritis and arthralgia was significantly higher in patients with M694V and E148Q mutations. Chest pain was reported more often in patients homozygous for M694V (61.4%). Pericardial effusion was documented in the echocardiography of 10.9% of the 229 children with chest pain. Some patients had both FMF and Henoch Schönlein purpura (HSP), and were more likely to harbor either homozygote M694V or E148Q mutations. The frequency of episodes was higher in patients with homozygous M694V mutations (number of attacks = 4.4 ± 1.6/month). Proteinuria was detected in 106 patients of cases (29.2%), at an average of 854 ± 145 mg/L. Most of the patients with proteinuria and elevated serum amyloid-A had homozygous M694V mutation.

CONCLUSION

The most common mutation in children in Turkey with FMF is the M694V mutation. Recurrent abdominal pain, arthritis or arthralgia, chest pain, and pericarditis were commonly seen in patients with M694V and E148Q mutations.

Febrile seizures in children with familial Mediterranean fever: Coincidence or association?

BACKGROUND

Familial Mediterranean fever (FMF) is an inherited disease characterized by recurrent bouts of fever and polyserositis and caused by MEditerranean FeVer gene (MEFV) mutations. Given the febrile characteristics of the disease one would expect higher frequency of febrile seizure in this group of pediatric patients.

OBJECTIVES

To evaluate the frequency of febrile seizure and related factors in patients with FMF.

METHODS

The children with the diagnosis of FMF were enrolled in the study. Information including clinical features, type of mutation and the history of febrile seizure were all noted.

RESULTS

A total of 97 patients, 43 (44.3%) girls with a median age of 7.93 ± 4.05 years (2-16) and a median follow-up period of 20.65 ± 24.33 months (6-135) were included in the study. The frequency of febrile seizure in children with FMF was found as 13.4%, which is higher than the general population [p = 0.04, OR: 2.9 (95% CI: 1.0-8.5)]. The allele frequency of exon 2 mutations in MEFV genes was higher in the patients with febrile seizure (p = 0.03). Frequency of FMF related clinical findings (fever, abdominal pain, arthralgia/myalgia, arthritis, chest pain and erysipelas-like erythema) was similar between the two groups. However, frequency of headache was higher in the patients with febrile seizure (p = 0.014).

CONCLUSION

The frequency of febrile seizure in children with FMF was found to be higher than the general population. Although this finding may be related to high fever during FMF attacks in individuals with genetic propensity of febrile seizure, it may also be a neurologic complication of FMF.

The myths we believed in familial Mediterranean fever: what have we learned in the past years?

Familial Mediterranean fever is the most common monogenic periodic fever syndrome over the world especially in the eastern Mediterranean. It presents with recurrent and self-limited inflammatory attacks of fever and polyserositis along with high acute-phase reactants. The disease is associated with mutations in the MEFV gene that encodes pyrin, a component of inflammasome, which leads to exaggerated inflammatory response through uncontrolled production of interleukin 1. With the identification of the gene associated with the disease, we believed that everything was solved and that this was an ordinary monogenic disease with autosomal recessive inheritance. However, through the breathtaking progress in the basic research field as well as the clinical care of these patients, we have understood that the picture for this monogenic disorder was more complicated than we had anticipated. In this review, we have discussed the myths we believed in familial Mediterranean fever and how they have evolved during the past years.

Clinical and genetic profile of children with periodic fever syndromes from a single medical center in South East Michigan

OBJECTIVE

To report a cohort of children with periodic fever syndromes (PFS) from Southeast Michigan.

METHODS

A retrospective review of medical records for patients referred for periodic fever over 5 years.

RESULTS

Sixty-six patients including 21 FMF, 15 PFAPA, four TRAPS and one patient with combined HIDS and FMF were included. In addition, 25 patients were categorized as clinical PFS (cPFS) based on their clinical features however their genetic workup was either negative or inconclusive. Majority of the patients with FMF were from Middle Eastern background (88 %), but positive family history was noted in only 55 % of cases. Mean age at diagnosis was 40.8 months with a mean delay in diagnosis of 24 months. Most common MEFV mutations were p.M694V and p.M694I. Four patients with TRAPS were from mixed European descent and age at onset of symptoms was 6, 12, 12, and 84 months respectively. TNFRSF1A sequence variants in the TRAPS patients included p.R121Q (R92Q) and p.C99G (C70G); one patient had a rare occurrence of a concurrent p.V726A/-MEFV mutation. One patient with HIDS and FMF presented with atypical overlapping PFS clinical manifestations and genetic evaluation showed a unique combination of p.I268T/p.V377I MVK mutations and p.E230K/-MEFV variant. All patients with PFAPA group were from mixed European descent, symptoms started at a mean age of 34.6 months with a mean delay in diagnosis of 23.3 months. Symptoms started during infancy in six patients. All patients fulfilled the diagnostic criteria for PFAPA. The mean age of onset of symptoms in cPFS group was 17.2 months. Empiric colchicine and glucocorticosteroids controlled flares in majority of patients with cPFS. No evidence of amyloidosis was found in this entire cohort of 66 patients after a mean of 29.2 months of follow-up.

CONCLUSION

PFS can present with atypical manifestations and should not be excluded based on a negative family history. Concomitant mutations in different autoinflammatory disorders genes can be present and possibly explain atypical manifestations. Various therapies may be considered even if genetic testing is inconclusive or negative.