The genetic basis of autosomal dominant familial Mediterranean fever

Current genetic diagnostics in inborn errors of immunity

New technologies in genetic diagnostics have revolutionized the understanding and management of rare diseases. This review highlights the significant advances and latest developments in genetic diagnostics in inborn errors of immunity (IEI), which encompass a diverse group of disorders characterized by defects in the immune system, leading to increased susceptibility to infections, autoimmunity, autoinflammatory diseases, allergies, and malignancies. Various diagnostic approaches, including targeted gene sequencing panels, whole exome sequencing, whole genome sequencing, RNA sequencing, or proteomics, have enabled the identification of causative genetic variants of rare diseases. These technologies not only facilitated the accurate diagnosis of IEI but also provided valuable insights into the underlying molecular mechanisms. Emerging technologies, currently mainly used in research, such as optical genome mapping, single cell sequencing or the application of artificial intelligence will allow even more insights in the aetiology of hereditary immune defects in the near future. The integration of genetic diagnostics into clinical practice significantly impacts patient care. Genetic testing enables early diagnosis, facilitating timely interventions and personalized treatment strategies. Additionally, establishing a genetic diagnosis is necessary for genetic counselling and prognostic assessments. Identifying specific genetic variants associated with inborn errors of immunity also paved the way for the development of targeted therapies and novel therapeutic approaches. This review emphasizes the challenges related with genetic diagnosis of rare diseases and provides future directions, specifically focusing on IEI. Despite the tremendous progress achieved over the last years, several obstacles remain or have become even more important due to the increasing amount of genetic data produced for each patient. This includes, first and foremost, the interpretation of variants of unknown significance (VUS) in known IEI genes and of variants in genes of unknown significance (GUS). Although genetic diagnostics have significantly contributed to the understanding and management of IEI and other rare diseases, further research, exchange between experts from different clinical disciplines, data integration and the establishment of comprehensive guidelines are crucial to tackle the remaining challenges and maximize the potential of genetic diagnostics in the field of rare diseases, such as IEI.

Updates on the role of epigenetics in familial mediterranean fever (FMF)

Familial Mediterranean Fever (FMF) is an autosomal recessive autoinflammatory disease caused by mutations in the MEFV (MEditerranean FeVer) gene that affects people originating from the Mediterranean Sea. The high variability in severity and clinical manifestations observed not only between ethnic groups but also between and within families is mainly related to MEFV allelic heterogeneity and to some modifying genes. In addition to the genetic factors underlying FMF, the environment plays a significant role in the development and manifestation of this disease through various epigenetic mechanisms, including DNA methylation, histone modification, and noncoding RNAs. Indeed, epigenetic events have been identified as an important pathophysiological determinant of FMF and co-factors shaping the clinical picture and outcome of the disease. Therefore, it is essential to better understand the contribution of epigenetic factors to autoinflammatory diseases, namely, FMF, to improve disease prognosis and potentially develop effective targeted therapies. In this review, we highlight the latest updates on the role of epigenetics in FMF.

Experimental models in Familial Mediterranean Fever (FMF): Insights into pathophysiology and therapeutic strategies

Familial Mediterranean Fever (FMF) is a recurrent polyserositis characterized by self-limiting episodes or attacks of fever along with serosal inflammation. It mainly impacts people of the Mediterranean and Middle Eastern basin. FMF is a recessive autoinflammatory condition caused by mutation in the MEFV gene located on chromosome 16p13. MEFV mutations lead to the activation of the pyrin inflammasome resulting in an uncontrolled release of IL-1β. Various in vitro, in vivo and ex vivo experimental models have been developed to further comprehend the etiology and pathogenesis of FMF. These models have been proven to be clinically relevant to human FMF and can provide significant information about biological systems with respect to this condition. Additionally, these models have provided pertinent contributions to the development of potent therapeutic strategies against FMF. In this review, we describe the different experimental models utilized in FMF and we focus primarily on the most widely used models that have produced prominent insights into the pathophysiology of the disease.

The Influence of Coexisting Familial Mediterranean Fever on Crohn's Disease: Data From an FMF Endemic Area

GOAL

The goal of this study was to evaluate the impact of coexisting familial Mediterranean fever (FMF) on Crohn's disease (CD) patients' phenotype and disease course in an endemic region for FMF.

BACKGROUND

CD and FMF are inflammatory diseases characterized by recurrent abdominal pain and fever attacks. The impact of coexisting FMF on CD patients' phenotype and disease course is currently unknown.

MATERIALS AND METHODS

We reviewed the medical records of 210 adult CD patients who were regularly followed up at a tertiary gastroenterology clinic between November 2006 and April 2018. The patients were divided into FMF positive (CD-FMF) and FMF negative (CD-control) groups. The severity of CD was assessed by the rate of hospitalization because of CD, the need for biological therapy, and whether surgery was performed for CD.

RESULTS

Eight (3.8%) of 210 CD patients have concomitant FMF, which is 35 to 40 times higher than expected in an endemic region for FMF. Baseline demographic parameters, location/behavior of the CD, and initial therapeutic regimens were similar between the 2 groups. The prevalence of peripheral arthritis was significantly higher in CD-FMF group (37.5% vs. 10.4%, respectively, P =0.04). A significantly greater proportion of the CD-FMF patients had received biological therapy (50% vs. 11.9%; P =0.012). Steroid dependence and CD-related hospitalization rates in the CD-FMF group were relatively higher but were not statistically significant (37.5% vs. 15.3 and 62.5% vs. 41.1%).

CONCLUSIONS

Our findings indicate that the disease course of CD tends to be more severe in patients with coexisting FMF.

R202Q prevalence in clinically diagnosed Familial Mediterranean Fever patients: 9 years of data analysis from 1570 patients living Central Black Sea region, Turkey

INTRODUCTION

Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent self-limiting fever, peritonitis, arthritis, and erysipelas-like-erythema, common among ethnic groups such as Turkish, Armenian, Arab, and Jewish. The disease is caused by mutations in the MEFV gene encoding the Pyrin. This study examines the genotypes of FMF patients from Amasya, Turkey.

METHOD

According to the Tel Hashomer criteria, one thousand five hundred seventy patients (871 female, 699 male, mean age 21.2 ± 15.5 years) living in Amasya Province and the surroundings were screened for sequence variants in the entire MEFV gene. Besides, mutation types and alleles were evaluated with clinical findings.

RESULTS

MEFV mutations and polymorphisms were found in 1413 of the 1570 patients (90%). Among these patients, 5 (0.3%) were double homozygous, 152 (9.7%) were homozygous, 373 (23.8%) were double heterozygous, and 882 (56.2%) were heterozygous. The most frequent genotype was R202Q (960, 43.5%) followed by M694V (n = 412, 18.7%), E148Q (n = 321, 14.6%), and M680I (n = 200, 9.1%). The most common clinical symptoms were abdominal pain (96.4%) and fever (91.3%).

CONCLUSIONS

The fact that the R202Q genotype, which is compatible with the known FMF clinic, is frequently seen shows that it should be included in routine molecular screenings of the patients. Functional studies of the R202Q variant pyrin protein should be performed to understand FMF better. Finally, it is unclear whether the R202Q genotype might be regarded as a mutation while being approved as a polymorphism in the inFevers database.

Comparison of posterior segment ocular parameters of Familial mediterranean fever with homozygous M694V mutation and carriers with heterozygous M694V mutation in children

PURPOSE

The aim of this study is to comparatively evaluate the posterior segment ocular parameters of Familial Mediterranean fever (FMF) patients, asymptomatic FMF carriers, and the healthy controls in the pediatric age group.

METHODS

The study included 30 FMF patients with homozygous M694V mutation in remission under colchicine therapy, 12 asymptomatic FMF carriers with heterozygous M694V mutation, and 41 age-sex-matched healthy controls. All patients underwent detailed eye examination, and peripapillary retinal nerve fiber layer (pRNFL) thickness, central macular thickness (CMT), subfoveal choroidal thickness (SCT), macular vascular densities, and foveal avascular zone (FAZ) areas were measured using swept-source optical coherence tomography angiography.

RESULTS

In this study, the mean pRNFL thickness was statistically significantly thinner (p = 0.010) in the FMF patients group compared to the FMF carriers group and the healthy control group, especially in the inferior quadrant of pRNFL (p = 0.042). The CMT in asymptomatic FMF carriers group was statistically significantly thicker than in FMF patients group (p = 0.037), especially the superior and inferior quadrants of macula were affected (p = 0.024; p = 0.020, respectively). In addition, this study showed that the changes of pRNFL thickness and CMT in pediatric patients with FMF were moderately correlated with the duration of diagnosis. There was no significant difference between the groups in terms of macular vascular densities and FAZ values.

CONCLUSION

FMF is a hereditary autoinflammatory disease that causes multi-organ involvement, and this study showed that posterior segment ocular parameters could be affected not only in FMF patients but also in asymptomatic FMF carriers.

An Update on Familial Mediterranean Fever

(1) Background: Familial Mediterranean Fever (FMF) is the prototypal autoinflammatory disease, characterized by recurrent bursts of neutrophilic inflammation. (2) Methods: In this study we look at the most recent literature on this condition and integrate it with novel information on treatment resistance and compliance. (3) Results: The canonical clinical presentation of FMF is in children with self-limited episodes of fever and polyserositis, associated with severe long-term complications, such as renal amyloidosis. It has been described anecdotally since ancient times, however only recently it has been characterized more accurately. We propose an updated overview on the main aspects of pathophysiology, genetics, diagnosis and treatment of this intriguing disease. (4) Conclusions: Overall, this review presents the all the main aspects, including real life outcome of the latest recommendation on treatment resistance of FMF, a disease, that not only helped understanding the pathophysiology of the auto inflammatory process but also the functioning of the innate immune system itself.

Indirect evaluation of amyloid deposition by ultrasonography and its relationship with MEFV gene mutation in FMF patients

OBJECTIVE

The most significant complication in familial mediterranean fever (FMF) patients is dysfunction and organ failure developing depending on amyloid deposition in organs. The golden standard for showing amyloid deposition is the biopsy; however, tissue stiffness was examined by shear wave elastography as a non-invasive method in a restricted number of studies conducted, and it is considered that amyloid deposition can be shown indirectly. In our study, we aimed to indirectly evaluate amyloid deposition in organs with Shear wave and Doppler ultrasonography and to reveal its relationship with MEFV gene mutation analysis.

METHOD

42 FMF patients with normal thyroid and renal function tests and 35 participants with no FMF symptoms were included in our study. FMF patients were grouped depending on their MEFV mutation analyses. Thyroid, salivary glands, and renal parenchymal tissue stiffness were evaluated by shear wave elastography. Thyroidal artery and both renal artery resistances were evaluated by Doppler ultrasonography.

RESULTS

Both parotis gland, thyroid and renal parenchymal stiffness and arterial vascular resistances in the patient group were found higher than the control group. A significant difference was not found in any parameters in classification based on gender. Tissue stiffness and vascular resistance values in the patient group with M694V homozygote mutation were found statistically significantly higher than the other mutation groups (p < 0.001).

CONCLUSION

Our study shows that identifying genetic mutation type in FMF patients will help determine possibly amyloidosis risk. Imaging of tissue stiffness by shear wave elastography and evaluation of vascular resistance by Doppler can be useful for routine screening of those patients.

Monocyte secretory profiling in a clinical and MEFV genotype-characterized cohort of Danish familial Mediterranean fever patients: diagnostic potential of CCL1 and CXCL1

OBJECTIVE

The autoinflammatory disease familial Mediterranean fever (FMF), characterized by recurrent attacks of sterile fever, serosal, and/or synovial inflammation, is caused by variants in the Mediterranean fever gene, MEFV, coding for the pyrin inflammasome sensor. The diagnosis of FMF is mainly based on clinical symptoms and confirmed by detection of disease-associated MEFV variants. However, the diagnosis is challenging among patients carrying variants of uncertain clinical significance (VUS). In this study, we aimed to identify potential FMF discriminatory diagnostic markers in a cohort of clinically characterized FMF patients.

METHOD

We established a cohort of clinically and MEFV genotype-characterized FMF patients by enrolling patients from major Danish hospitals (n = 91). The secretory profile of pyrin inflammasome-activated monocytes from healthy donors (HDs) and MEFV-characterized FMF patients (n = 28) was assessed by analysing cell supernatants for a custom-designed panel of 23 cytokines, chemokines, and soluble tumour necrosis factor receptors associated with monocyte and macrophage function.

RESULTS

MEFV genotypes in Danish FMF patients were associated with age at symptom onset (p < 0.05), FMF among relatives (p < 0.01), proportion of patients in colchicine treatment (p < 0.01), and treatment response (p < 0.05). Secretion of chemokines CCL1 and CXCL1 from pyrin-activated FMF monocytes was significantly decreased compared to HDs (p < 0.05), and could discriminate FMF patients with 'non-confirmatory' MEFV genotypes from HDs with 80.0% and 70.0% sensitivity for CCL1 and CXCL1, respectively (p < 0.05).

CONCLUSION

Our data suggest that a functional diagnostic assay based on CCL1 or CXCL1 levels in pyrin-activated patient monocytes may contribute to FMF diagnosis in patients with VUS.

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.

Rare genetic causes of meningitis and encephalitis

Differential diagnosis of meningitis and encephalitis is often very challenging because it cannot be determined based on symptoms, and the diseases have various causes. This article explains rare genetic causes of meningitis and encephalitis. Autoinflammatory disorders include cryopyrin-associated periodic syndromes, familial Mediterranean fever, and tumor necrosis factor receptor-associated periodic syndrome. Furthermore, other genetic disorders, such as complement factor I deficiency, phosphatidylinositol glycan anchor biosynthesis class T mutation, and neuronal intranuclear inclusion disease, can present as meningitis and encephalitis.

Spectrum of MEFV gene mutations in 4,256 familial Mediterranean fever patients from Iran: a comprehensive systematic review

Background

Familial Mediterranean fever (FMF), known as a disease with a high prevalence rate among Armenian, Turkish, Jewish, and Arab descent populations, occurs as a result of pathogenic variants in mediterranean fever (MEFV) gene. The aim of this study was to review the spectrum and frequency of MEFV gene mutations reported among Iranian FMF patients.

Methods

After performing a systematic review of the literature and implementation of inclusion and exclusion criteria, 16 articles published between 2004 and 2020, involving 4,256 Iranian FMF patients, were included.

Results

A total of 38 different MEFV gene mutations were identified. The most common mutations among Iranian FMF patients were: p.M694V (c.2080A > G) (20.27%), p.E148Q (c.442G > C) (10.27%), p.V726A (c.2177T > C) (8.24%), p.M680I (both c.2040G > C and c.2040G > A) (7.20%), p.R761H (c.2282G > A) (2.1%), and p.M694I (c.2082G > A) (2. 1%). The frequencies of these mutations were significantly different in different parts of the country.

Conclusions

The ranks and frequencies of p.M694V, p.E148Q, p.V726A, p.M680I, and p.M694I in our population were closer to those observed in the Mediterranean countries, especially in the Middle Eastern Arab populations. Although some comprehensive studies have been performed on Azeri Turkish patients living in northwestern Iran, studies in other areas, especially in eastern Iran, have been very limited. One reason for this observation could be due to the low frequency of FMF patients in those areas. Regardless of the reason for this, the exact spectrum and frequency of MEFV gene mutations in Iranian FMF patients remain unclear. Therefore, comprehensive future studies in different parts of the country are recommended.

A Novel mRNA Modification Mutation in a Patient With Ligneous Conjunctivitis Coexisting With Heterozygous Familial Mediterranean Fever Mutation

PURPOSE

To describe a novel mRNA mutation associated with ligneous conjunctivitis (LC) in a patient with heterozygous familial Mediterranean fever (FMF) mutation.

METHODS

Case presentation of a patient with LC and heterozygous FMF mutation. The patient was evaluated for various genetically predisposed inflammatory diseases through whole exome sequencing.

RESULTS

LC is a rare inflammatory ocular pathology presenting with recurrent conjunctivitis episodes with eosinophilic fibrin-rich pseudomembranes. FMF is an autoinflammatory disease presenting with recurrent episodes of fever, arthritis, and other inflammatory conditions. Various plasminogen (PLG) gene mutations have been identified in LC, whereas a variety of mutations in the Mediterranean fever (MEFV) gene have been identified in FMF patients. Based on the inflammatory nature of both pathologies, we aimed to evaluate and identify any potential common genetic pathway. We were not able to identify any mutation in PLG gene through whole gene sequencing; however, the patient was positive for heterozygous M680I FMF mutation, and we observed 22% of NM_000301.3:c.2130T>G (p.T710=) variant in mRNA isolated from affected tissue, which was not present in DNA sequence.

CONCLUSIONS

To the best of our knowledge, this is the first case of LC caused by an mRNA mutation coexisting with another genetically predisposed autoinflammatory disease mutation.

Molecular mechanisms of phenotypic variability in monogenic autoinflammatory diseases

Monogenic autoinflammatory diseases are a group of rheumatologic disorders caused by dysregulation in the innate immune system. The molecular mechanisms of these disorders are linked to defects in inflammasome-mediated, NF-κB-mediated or interferon-mediated inflammatory signalling pathways, cytokine receptors, the actin cytoskeleton, proteasome complexes and various enzymes. As with other human disorders, disease-causing variants in a single gene can present with variable expressivity and incomplete penetrance. In some cases, pathogenic variants in the same gene can be inherited either in a recessive or dominant manner and can cause distinct and seemingly unrelated phenotypes, although they have a unifying biochemical mechanism. With an enhanced understanding of protein structure and functionality of protein domains, genotype-phenotype correlations are beginning to be unravelled. Many of the mutated proteins are primarily expressed in haematopoietic cells, and their malfunction leads to systemic inflammation. Disease presentation is also defined by a specific effect of the mutant protein in a particular cell type and, therefore, the resulting phenotype might be more deleterious in one tissue than in another. Many patients present with the expanded immunological disease continuum that includes autoinflammation, immunodeficiency, autoimmunity and atopy, which necessitate genetic testing.

Founder variants and population genomes-Toward precision medicine

Human migration and community specific cultural practices have contributed to founder events and enrichment of the variants associated with genetic diseases. While many founder events in isolated populations have remained uncharacterized, the application of genomics in clinical settings as well as for population scale studies in the recent years have provided an unprecedented push towards identification of founder variants associated with human health and disease. The discovery and characterization of founder variants could have far reaching implications not only in understanding the history or genealogy of the disease, but also in implementing evidence based policies and genetic testing frameworks. This further enables precise diagnosis and prevention in an attempt towards precision medicine. This review provides an overview of founder variants along with methods and resources cataloging them. We have also discussed the public health implications and examples of prevalent disease associated founder variants in specific populations.

Novel variants of MEFV and NOD2 genes in familial hidradenitis suppurativa: A case report

We report a two-generation Canadian family of Armenian ancestry with hidradenitis suppurativa where novel mutations in MEVF and NOD2 genes were identified. The father and both children shared a mild-to-moderate hidradenitis suppurativa phenotype together with the features of follicular occlusion (e.g. acne and scalp folliculitis). Based on our findings and previous literature, we recommend considering genetic testing with a periodic fever/autoinflammatory disorder panel in patients with a strong family history of hidradenitis suppurativa and lack of common triggers such as smoking and being overweight.

Autoinflammatory Diseases in Childhood

Autoinflammatory diseases are characterized by recurrent fevers and clinical findings of impaired natural immunity and can involve various organ systems. The concept of autoinflammatory disease emerged after the definition of familial Mediterranean fever and tumor necrosis factor receptor-associated periodic syndrome. This new disease group was considered to differ from the standard concept of autoimmune diseases, which is relatively better known in terms of basic features, such as defects in innate immunity and the absence of antibodies. A better understanding has been achieved regarding the genetic and pathogenetic mechanisms of this relatively new disease group over the past 20 years since they were first diagnosed, which have led to some changes in the concept of autoinflammatory diseases. The recent definition classifies autoinflammatory disease to be a wide range of diseases with different clinical features, mainly accompanied by changes in innate immune and rarely in humoral immunity. The spectrum of autoinflammatory diseases is rapidly expanding owing to recent developments in molecular sciences and genetics. This review article discusses the clinical features, classification criteria, treatment options, and long-term prognosis of periodic fever, aphthous stomatitis, pharyngitis, adenitis syndrome, and other common autoinflammatory diseases in the light of current literature.

British kindred with dominant FMF associated with high incidence of AA amyloidosis caused by novel MEFV variant, and a review of the literature

OBJECTIVES

Hereditary systemic autoinflammatory diseases are rare genetic disorders, which if untreated, can be complicated by AA amyloidosis leading to renal failure and premature death. Our objective was to find a genetic cause in a British family with a dominantly inherited autoinflammatory disease complicated by AA amyloidosis.

METHODS

The index patient and his sister underwent comprehensive clinical and laboratory assessment including the next-generation sequencing panel targeting autoinflammatory genes. Subsequently, other relatives underwent clinical evaluation and genetic testing. Screening of the SAA1 gene was performed in all symptomatic cases.

RESULTS

The index case and his sister presented with proteinuria due to AA amyloidosis. They have been suffering from episodes of fever accompanied by severe abdominal and chest pain, arthritis and erythema since childhood. Their father died aged 52 years from complications following a cadaveric renal transplantation. The post-mortem examination demonstrated AA amyloidosis. The index case's grandmother, two paternal cousins and two of their children described similar symptoms. All symptomatic individuals had excellent responses to colchicine. Next-generation sequencing analysis identified a single MEFV p.P373L variant in the index case, his sister and subsequently, in symptomatic family members. Sequencing of the SAA1 gene revealed all cases were heterozygous for the SAA1.1 allele.

CONCLUSION

Typically FMF is an autosomal recessive disorder; nonetheless rare cases of dominantly inherited disease have previously been described. Here we report a novel MEFV variant p.P373L, causing dominant FMF complicated by AA amyloidosis in four generations of a British family.

Optical coherence tomography-angiographic vascular densities in Familial Mediterranean Fever (FMF) Patients with M694V Mutations

Familial Mediterranean fever (FMF) is a hereditary auto-inflammatory disease with accompanying findings of amyloidosis and vasculitis. M694V is one of the most common mutations associated with amyloidosis. This study compared the macular optical coherence tomography angiography measurements in FMF patients who were genetically verified to carry the M694V mutation of the MEFV gene to those in healthy controls. The vessel densities (VDs) of superficial (SVP) and deep vascular plexus (DVP) of the retina, and choriocapillaris, foveal avascular zone (FAZ) perimetry, foveal VD 300µ around the FAZ (FD-300), acirculatory index (AI) and non-flow area were measured with  optical coherence tomography angiography (OCT-A). The FMF and control groups were matched for age and gender. Compound heterozygous pathogenic variants were excluded. Thirty-eight FMF patients with M694V mutations (28 heterozygous and 10 homozygous) and 40 healthy controls were included. The two groups were similar with the regard to age and gender (P=0.88 and P=0.49, respectively). None of the investigated parameters, including the vessel densities of the SVP and DVP, and choriocapillaris, FAZ perimetry, FD-300, AI, and non-flow area showed a statistically significant difference between the FMF and control groups. The macular vessel density measurements and FAZ parameters of FMF patients with M694V mutations do not differ from age- and sex-matched healthy controls.

Current and future advances in genetic testing in systemic autoinflammatory diseases

Systemic autoinflammatory diseases (SAIDs) are a group of inflammatory disorders caused by dysregulation in the innate immune system that leads to enhanced immune responses. The clinical diagnosis of SAIDs can be difficult since individually these are rare diseases with considerable phenotypic overlap. Most SAIDs have a strong genetic background, but environmental and epigenetic influences can modulate the clinical phenotype. Molecular diagnosis has become essential for confirmation of clinical diagnosis. To date there are over 30 genes and a variety of modes of inheritance that have been associated with monogenic SAIDs. Mutations in the same gene can lead to very distinct phenotypes and can have different inheritance patterns. In addition, somatic mutations have been reported in several of these conditions. New genetic testing methods and databases are being developed to facilitate the molecular diagnosis of SAIDs, which is of major importance for treatment, prognosis and genetic counselling. The aim of this review is to summarize the latest advances in genetic testing for SAIDs and discuss potential obstacles that might arise during the molecular diagnosis of SAIDs.

The Pyrin Inflammasome in Health and Disease

The pyrin inflammasome has evolved as an innate immune sensor to detect bacterial toxin-induced Rho guanosine triphosphatase (Rho GTPase)-inactivation, a process that is similar to the “guard” mechanism in plants. Rho GTPases act as molecular switches to regulate a variety of signal transduction pathways including cytoskeletal organization. Pathogens can modulate Rho GTPase activity to suppress host immune responses such as phagocytosis. Pyrin is encoded by MEFV, the gene that is mutated in patients with familial Mediterranean fever (FMF). FMF is the prototypic autoinflammatory disease characterized by recurring short episodes of systemic inflammation and is a common disorder in many populations in the Mediterranean basin. Pyrin specifically senses modifications in the activity of the small GTPase RhoA, which binds to many effector proteins including the serine/threonine-protein kinases PKN1 and PKN2 and actin-binding proteins. RhoA activation leads to PKN-mediated phosphorylation-dependent pyrin inhibition. Conversely, pathogen virulence factors downregulate RhoA activity in a variety of ways, and these changes are detected by the pyrin inflammasome irrespective of the type of modifications. MEFV pathogenic variants favor the active state of pyrin and elicit proinflammatory cytokine release and pyroptosis. They can be inherited either as a dominant or recessive trait depending on the variant's location and effect on the protein function. Mutations in the C-terminal B30.2 domain are usually considered recessive, although heterozygotes may manifest a biochemical or even a clinical phenotype. These variants are hypomorphic in regard to their effect on intramolecular interactions, but ultimately accentuate pyrin activity. Heterozygous mutations in other domains of pyrin affect residues critical for inhibition or protein oligomerization, and lead to constitutively active inflammasome. In healthy carriers of FMF mutations who have the subclinical inflammatory phenotype, the increased activity of pyrin might have been protective against endemic infections over human history. This finding is supported by the observation of high carrier frequencies of FMF-mutations in multiple populations. The pyrin inflammasome also plays a role in mediating inflammation in other autoinflammatory diseases linked to dysregulation in the actin polymerization pathway. Therefore, the assembly of the pyrin inflammasome is initiated in response to fluctuations in cytoplasmic homeostasis and perturbations in cytoskeletal dynamics.

How to prescribe a genetic test for the diagnosis of autoinflammatory diseases?

The systemic autoinflammatory disorders (SAIDs) are associated with dysregulation of the innate immune system, affecting pro-inflammatory cytokines and apoptosis pathways. The spectrum of SAIDs continues to grow with over 30 different disorders identified to date. The main indication for genetic referral is when a patient presents with clinical symptoms consistent with one or more of the SAIDs. Thus, in making a referral for DNA screening, clinical information that supports the choice for screening of one or more SAIDs genes is required. Many of the SAIDs can display overlapping, partial or atypical symptoms, which makes the differential diagnosis extremely difficult and thus heavily dependent on genetic testing. Various attempts have been aimed at improving the efficiency of SAIDs diagnosis by proposing a set of clinical criteria to guide the genetic analysis of the SAIDs. In the last decade, due to application of the next-generation sequencing (NGS) the genetic diagnosis in patients with SAIDs have greatly improved; novel diseases and disease-associated genes have been identified and remarkable progress has been made in the genetic characterization of the undiagnosed patients and the sporadic cases. To date more than 800 variants have been recorded on the Infevers database, an online repository for DNA changes in genes associated with SAIDs (http://fmf.igh.cnrs.fr/ISSAID/infevers/). Recently, it has been updated with the new guidelines for classification of genetic variants pathogenicity in the in four most recognised SAIDs genes: MEFV, TNFRSF1A, NLRP3 and MVK.

Association between MEFV polymorphisms and the susceptibility to ankylosing spondylitis in a Chinese Han population: A case-control study

The aim of this study was to explore the genetic association of Mediterranean fever (MEFV) gene polymorphisms rs3743930 and rs11466023 with ankylosing spondylitis (AS) susceptibility in a cohort of Chinese Han population.Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method was used for genotyping MEFV polymorphisms in 131 AS patients and 127 healthy controls. Chi-square test was employed to compare the genotype and allele distributions between the case and control groups. Odds ratio (OR) with 95% confidence interval (CI) was calculated to assess the association between MEFV gene polymorphisms and AS incidence.The frequency of the G allele of MEFV polymorphism rs3743930 in the AS group was significantly higher than that in the healthy control group (36.64% vs 28.35%, P < .05). And individuals carrying the GG genotype showed 2.896 folds higher risk of developing AS when compared with CC genotype carriers (OR = 2.896, 95% CI = 1.115-7.519). But no significant differences were detected in either genotype or allele distributions between case and control groups for the polymorphism rs11466023 (P > .05).MEFV gene polymorphism rs3743930 might be significantly associated with AS susceptibility in Chinese Han population, and its G allele might predict high risk of AS.

Genetic Profile of Patients with Familial Mediterranean Fever (FMF): Single Center Experience at King Hussein Medical Center (KHMC)

Objective:

To describe the spectrum of genetic mutations in patients with clinical diagnosis of Familial Mediterranean Fever.

Method:

This is a retrospective study of 3359 sera samples for patient with clinical diagnosis of FMF, over a period of 6 years. The samples were tested for 12 mutations of the MEFV gene by PCR& hybridization of the PCR product with Probes immobilized as an array of panel lines.

Results:

A total of 1868 (55.6%) samples were found negative, and one or more mutations were detected in 1491 (44.4%) distributed along the mutations. Of the positive results, the Frequency of the mutations was as follows, the M694V was the most common mutation 30%, followed by E 148Q 21.5%, V 726 A 20%, M6801 G/C 9%, M6941 8.3%, P369s 3.7%, A744S 3.1% and 4.2% among the 4 remaining mutations.

Conclusion:

Frequency of common mutations in our study show similar results in comparisons with Mediterranean countries like Egypt, Turkey, and Syria with the most common mutation in our study being M694V followed by E148 Q.

Familial Mediterranean fever and periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome: shared features and main differences

Autoinflammatory diseases are characterized by fever attacks of varying durations, associated with variety of symptoms including abdominal pain, lymphadenopathy, polyserositis, arthritis, etc. Despite the diversity of the clinical presentation, there are some common features that make the differential diagnosis of the autoinflammatory diseases challenging. Familial Mediterranean fever (FMF) is the most commonly seen autoinflammatory conditions, followed by syndrome associated with periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA). In this review, we aim to evaluate disease characteristics that make a diagnosis of FMF and PFAPA challenging, especially in a regions endemic for FMF. The ethnicity of patient, the regularity of the disease attacks, and the involvement of the upper respiratory systems and symphonies could be helpful in differential diagnosis. Current data from the literature suggest the use of biological agents as an alternative for patients with FMF and PFAPA who are non-responder classic treatment options. More controlled studies are needed to evaluate the efficacy and safety of this strategy.

Analysis of microRNAs in familial Mediterranean fever

OBJECTIVES

Although Familial Mediterranean fever (FMF) is categorized as autosomal recessive, frequent exceptions to this model exist and therefore we aimed to search epigenetic modifications in this disease.

METHODS

Ten M694V homozygous FMF patients (the most severe phenotype) were recruited for this study. Patients with inflammatory flare were excluded. Total RNA was extracted from peripheral blood, and microRNA expression profiled using NanoString nCounter technology. These patients were compared to 10 healthy age- and sex-matched controls.

RESULTS

Seven hundred nighty-eight mature human miRNAs were probed, 103 of which had expression levels above the negative control probes. Seven miRNAs showed significant differences in expression in samples from FMF patients compared to healthy controls: four miRNAs were upregulated (miR-144-3p, miR-21-5p, miR-4454, and miR-451a), and three were downregulated (miR-107, let-7d-5p, and miR-148b-3p).

CONCLUSION

In this pilot study, we identified epigenetic modifications in clinically quiescent FMF patients. More studies are required for exploration of their contribution to FMF pathogenesis and their potential role as clinical biomarkers.

Does thiol-disulphide balance show oxidative stress in different MEFV mutations?

Many studies have shown that oxidative stress levels increase in patients with Familial Mediterranean Fever (FMF). Thiols are a class of compounds that include a sulfhydryl group (-SH) and can react with free oxygen radicals to protect tissues. We aimed to investigate thiol-disulphide homeostatic status in FMF patients and examined the effect of different mutations in the MEFV gene on the thiol-disulphide balance. We investigated thiol-disulphide parameters in patients with FMF and healthy controls. To determine the differential effect of MEFV gene mutations on thiol-disulphide balance, subjects were divided into five groups based on homozygous or compound heterozygous exon 10 and nonexon 10 mutations. Tests of thiol-disulphide homeostasis were conducted using the automated spectrophotometric method. Patients with FMF had significantly lower native thiol [433.8 µmol/l (243.3-536.4) vs. 484.1 µmol/L (340.2-612.3), p  < 0.001], total thiol levels [459.7 µmol/L (281.3-575.4) vs. 529.9 µmol/L (363-669.5), p < 0.001], and disulphide levels [14.0 µmol/l (2.7-33.3) vs. 24.4 µmol/l (7.2-36.6), p < 0.001] compared to the control group. Moreover, disulphide/native thiol (3.4 ± 1.7 vs. 4.7 ± 1.3, p < 0.001) and disulphide/total thiol (3.1 ± 1.4 vs. 4.3 ± 1.0 p < 0.001) were also detected lower in the FMF group compared to the control group. But the native thiol/total thiol ratios (93.6 ± 2.9 vs. 91.3 ± 2.1, p < 0.001) were higher in the FMF group. There was no significant difference between the native thiol, total thiol, and disulphide levels of individuals with nonexon 10 homozygous or compound heterozygous (Group 1), nonexon 10-exon 10 compound heterozygous (Group 2), exon 10 homozygous or compound heterozygous (Group 3), and heterozygous (Group 4) mutations. However, these parameters significantly differed from those of the healthy control group. Since no differences were found in our study between thiol and disulfide levels of Groups 1, 2 and 3, we believe that this rate cannot be shown as an indicator of oxidative damage in different mutations of FMFs. To the best of our knowledge, this study is the first study that demonstrates the effect of different FMF mutations on the thiol-disulphide balance.

Familial Mediterranean fever in childhood: a single-center experience

The aim of this study is to present demographic and clinical features, MEFV mutation variations, and treatment response of a large number of pediatric familial Mediterranean fever (FMF) patients from a single tertiary centre. Moreover, we aimed to investigate the current outcome of FMF, namely frequency of amyloidosis in children with FMF. We evaluated 708 FMF patients who were followed up in our clinic and who were under colchicine treatment for at least 6 months. The data were recorded from patient records and also verified by negotiations with patients and parents. The male/female proportion of the cohort was 1.05/1 (n = 362/346). Abdominal pain (89.5%, n = 634) was the most common manifestation of FMF episodes, followed by fever (88.8%, n = 629) and arthritis (40.7%, n = 288). However, arthritis in 23 (8%) of the 288 cases was not self-limited; and they subsequently diagnosed with juvenile idiopathic arthritis in addition to FMF. Homozygote or heterozygote M694V mutation was more frequent in patients with arthritis (63.2%) and chronic arthritis (69.6%) than the whole cohort (53.8%). Erythrocyte sedimentation rate and CRP level were in high levels even during attack-free period in 13.9% (n = 97/697) and 11% (n = 78/670) of the patients, respectively. Proteinuria was found in ten patients (1.4%). Amyloidosis was confirmed by renal biopsy in only two of these cases who were homozygous for M694V and compound heterozygous for M694V/M680I. 47 (6.6%) subjects were considered as colchicine resistant. Homozygote M694V mutation was the most frequent mutation in those resistant cases (63.8%, n = 30), followed by compound heterozygote mutation of M694V/M680I (6.3%, n = 3). Homozygous M694V mutation are still the most frequent mutation and associated with the most severe clinical picture and the worst outcome in Turkish children. M694V genotype seems to be more frequently associated with arthritis as well as with chronic arthritis than other genotypes. Recurrence of FMF episodes as well as amyloidosis could only be managed via strict compliance to colchicine treatment. Frequency of amyloidosis significantly decreased compared to the previous studies. A favorable outcome could be obtained with the anti IL-1 in colchicine-resistant FMF patients.

Cold Exposure Related Fever with an Mediterranean Fever (MEFV) Gene Mutation

Familial Mediterranean fever (FMF) is a genetic autoinflammatory disease characterized by recurrent fever with serosal inflammation. We experienced a 53-year-old male who had been suffering from periodic attacks with slight fever and myalgia which were mainly triggered by cold exposure in winter. Although his clinical course did not satisfy the criteria for familial Mediterranean fever, heterozygous E148Q/M694I mutation in the Mediterranean fever (MEFV) gene was detected. Further attacks were prevented by treatment with colchicine. Attention should therefore be paid to the possibility of atypical FMF symptoms, which should be accurately diagnosed by genetic analyses to prevent the development of amyloidosis.

Evidence of digenic inheritance in autoinflammation-associated genes

Familial Mediterranean fever (FMF) has traditionally been considered as a monogenic autosomal recessive disorder caused by mutations in the MEFV gene with highest incidence among Mediterranean populations. In a considerable number of patients with typical FMF, only one MEFV mutation was identified and the possibility that more than one autoinflammatory gene may be responsible for their disease was investigated. In the present study, an extensive search for possible mutations in three hereditary recurrent fever (HRF) genes was performed in 128 MEFV heterozygous Greek-Cypriots clinically diagnosed based on their phenotype with FMF-like disease from a previous study. Sequence analysis was performed for MVK, TNFRSF1A and NLRP3 genes which is also known to cause HRFs. In total, three patients were identified with heterozygous mutations and a second mutation in an autoinflammatory gene. Two patients carried a MEFV mutation and a NLRP3 mutation, and an additional third carried a MEFV mutation and a TNFRSF1A mutation. Patient 1 carried MEFV p.[Val726Ala] (NM_000243.2:c.2177T>C) and NLRP3 p.[Val198Met] (NM_001243133.1:c.592G>A) variants and patient 2 carried MEFV p.[Glu148Gln] (NM_000243.2:c.442G>C) variant which is of uncertain significance and NLRP3 p.[Arg176Trp] (NM_001243133.1:c.526C>T). Lastly, patient 3 was identified to carry MEFV p.[Met694Val] (NM_000243.2:c.2080A>G) and TNFRSF1A p.[Arg121Gln] (NM_001065.3:c.362G>A) variants. The results from this study indicate that screening of genes known to cause HRFs in patients already identified with a single MEFV mutation, can reveal quite rare but potentially causative mutational combinations at different loci. Such interaction provide further evidence for possible locus-locus interactions and phenotypes resulting from digenic inheritance.

Monogenic Autoinflammatory Diseases with Mendelian Inheritance: Genes, Mutations, and Genotype/Phenotype Correlations

Autoinflammatory diseases (AIDs) are a genetically heterogeneous group of diseases caused by mutations of genes encoding proteins, which play a pivotal role in the regulation of the inflammatory response. In the pathogenesis of AIDs, the role of the genetic background is triggered by environmental factors through the modulation of the innate immune system. Monogenic AIDs are characterized by Mendelian inheritance and are caused by highly penetrant genetic variants in single genes. During the last years, remarkable progress has been made in the identification of disease-associated genes by using new technologies, such as next-generation sequencing, which has allowed the genetic characterization in undiagnosed patients and in sporadic cases by means of targeted resequencing of a gene panel and whole exome sequencing. In this review, we delineate the genetics of the monogenic AIDs, report the role of the most common gene mutations, and describe the evidences of the most sound genotype/phenotype correlations in AID.

Prevalence of common MEFV mutations and carrier frequencies in a large cohort of Iranian populations

Familial Mediterranean fever (FMF) is a hereditary autoinflammatory disorder caused by mutations in the MEFV gene. The disease is especially common among Armenian, Turkish, Jewish and Middle East Arab populations. To identify the frequency and the spectrum of common MEFV mutations in different Iranian populations, we investigated a cohort of 208 unselected asymptomatic individuals and 743 FMF patients. Nine hundred and fifty-one samples were analysed for the presence of 12 MEFV mutations by PCR and reverse-hybridization (FMF StripAssay, ViennaLab, Vienna, Austria). Confirmatory dideoxy sequencing of all MEFV gene exons was performed for 39 patients. Fifty-seven (27.4%) healthy individual carried mutant MEFV alleles. Three hundred and ninety-one (52.6%) FMF patients were found positive for either one (172/743; 23.1%), two or three MEFV mutations. Using dideoxy sequencing, three novel variants, A66P, R202W and H300Q, could be identified. Our analysis revealed an allele frequency and carrier rate of 15.6 and 27.4%, respectively, among healthy Iranians. Still moderate compared to neighbouring Armenia, but higher than in Turkey or Iraq, these data suggest that FMF is remarkably common among Iranian populations. E148Q was most frequent in the group of healthy individuals, whereas M694V was the most common mutation among FMF patients, thereby corroborating previous studies on MEFV mutational spectra in the Middle East. Accordingly, MEFV mutations are frequent in healthy Iranian individuals across different ethnic groups. Based on this finding, the awareness for FMF and the implementation of augmented carrier screening programmes considering the multiethnic nature of the Iranian population should be promoted.

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.

Lessons from characterization and treatment of the autoinflammatory syndromes

PURPOSE OF REVIEW

The list of genes associated with systemic inflammatory diseases has been steadily growing because of the explosion of new genomic technologies. Significant advances in the past year have deepened our understanding of the molecular mechanisms linked to inflammation and elucidated insights on the efficacy of specific therapies for these and related conditions. We review the molecular pathogenesis of four recently characterized monogenic autoinflammatory diseases: haploinsufficiency of A20, otulipenia, a severe form of pyrin-associated disease, and a monogenic form of systemic juvenile idiopathic arthritis.

RECENT FINDINGS

The scope of autoinflammation has been broadened to include defects in deubiquitination and cellular redox homeostasis. At the clinical level, we discuss the biological rationale for treatment with cytokine inhibitors and colchicine in respective conditions and the use of interleukin-1 antagonism for diagnostic and therapeutic purposes in the management of undifferentiated autoinflammatory disorders.

SUMMARY

Gene discoveries coupled with studies of molecular function provide knowledge into the biology of inflammatory responses and form the basis for genomically informed therapies. Diseases of dysregulated ubiquitination constitute a novel category of human inflammatory disorders.

Familial autoinflammation with neutrophilic dermatosis reveals a regulatory mechanism of pyrin activation

Pyrin responds to pathogen signals and loss of cellular homeostasis by forming an inflammasome complex that drives the cleavage and secretion of interleukin-1β (IL-1β). Mutations in the B30.2/SPRY domain cause pathogen-independent activation of pyrin and are responsible for the autoinflammatory disease familial Mediterranean fever (FMF). We studied a family with a dominantly inherited autoinflammatory disease, distinct from FMF, characterized by childhood-onset recurrent episodes of neutrophilic dermatosis, fever, elevated acute-phase reactants, arthralgia, and myalgia/myositis. The disease was caused by a mutation in MEFV, the gene encoding pyrin (S242R). The mutation results in the loss of a 14-3-3 binding motif at phosphorylated S242, which was not perturbed by FMF mutations in the B30.2/SPRY domain. However, loss of both S242 phosphorylation and 14-3-3 binding was observed for bacterial effectors that activate the pyrin inflammasome, such as Clostridium difficile toxin B (TcdB). The S242R mutation thus recapitulated the effect of pathogen sensing, triggering inflammasome activation and IL-1β production. Successful therapy targeting IL-1β has been initiated in one patient, resolving pyrin-associated autoinflammation with neutrophilic dermatosis. This disease provides evidence that a guard-like mechanism of pyrin regulation, originally identified for Nod-like receptors in plant innate immunity, also exists in humans.

Pyrin inflammasome activation and RhoA signaling in the autoinflammatory diseases FMF and HIDS

Mutations in the genes encoding pyrin and mevalonate kinase (MVK) cause distinct interleukin-1β (IL-1β)-mediated autoinflammatory diseases: familial Mediterranean fever (FMF) and hyperimmunoglobulinemia D syndrome (HIDS). Pyrin forms an inflammasome when mutant or in response to bacterial modification of the GTPase RhoA. We found that RhoA activated the serine-threonine kinases PKN1 and PKN2 that bind and phosphorylate pyrin. Phosphorylated pyrin bound to 14-3-3 proteins, regulatory proteins that in turn blocked the pyrin inflammasome. The binding of 14-3-3 and PKN proteins to FMF-associated mutant pyrin was substantially decreased, and the constitutive IL-1β release from peripheral blood mononuclear cells of patients with FMF or HIDS was attenuated by activation of PKN1 and PKN2. Defects in prenylation, seen in HIDS, led to RhoA inactivation and consequent pyrin inflammasome activation. These data suggest a previously unsuspected fundamental molecular connection between two seemingly distinct autoinflammatory disorders.

Autosomal dominant familial Mediterranean fever in Northern European Caucasians associated with deletion of p.M694 residue-a case series and genetic exploration

OBJECTIVE

This study was undertaken to characterize the phenotype and response to treatment in patients with autosomal dominant FMF caused by MEFV p.M694del mutation and to use haplotype reconstruction to investigate the possibility of common ancestry.

METHODS

MEFV gene was analysed in 3500 subjects with suspected FMF referred to a single UK centre between 2002 and 2014. Patients with p.M694del underwent additional screening of the SAA1 gene as well as haplotype reconstruction of the MEFV locus.

RESULTS

The p.M694del variant was identified in 21 patients, sharing an identical disease haplotype that appears to have arisen about 550 years ago. The SAA1.1 allele was found in four patients, including two with AA amyloidosis. The clinical features comprised typical FMF symptoms with median age at onset of 18 years; three patients presented with AA amyloidosis, of whom two had had symptoms of FMF in retrospect. Fifteen patients had received colchicine treatment, all with excellent responses.

CONCLUSION

The p.M694del variant is associated with autosomal dominantly inherited FMF in Northern European Caucasians. Symptoms may develop later in life than in classical recessive FMF but are otherwise similar, as is the response to colchicine treatment. The 14% incidence of AA amyloidosis may reflect delay in diagnosis associated with extreme rarity of FMF in this population. The common haplotype suggests a single founder living in about 1460.

Diffuse and multifocal nephrogenic adenoma with Familial Mediterranean Fever: a case report with molecular study

Nephrogenic adenoma, also referred to nephrogenic metaplasia, is a benign proliferative lesion of urothelium, usually associated with chronic physical stimuli or inflammation. Familial Mediterranean fever is an inherited autosomal recessive disease characterized by recurrent short episodes of fever. The site of mutation is found in MEFV gene which controls inflammatory responses. We have experienced a case of nephrogenic adenoma in a 16-year-old girl with Familial Mediterranean Fever, showing proliferative lesions diffusely in the urinary bladder and multifocally in the other parts of urinary tract. These lesions disappeared after colchicine treatment. We searched for MEFV gene mutation using the specimen from the resected urinary bladder and detected heterozygous mutation of E148Q. There is a possibility that control of inflammation caused by the surgery for vesicoureteral reflux in the local site didn’t work well on the background of heterozygous mutation of MEFV gene, and as a result, nephrogenic adenoma appeared. This is the first report of a combination of two rare diseases. We have to be aware that nephrogenic adenoma can occur in association with Familial Mediterranean Fever, and the former condition should be taken into consideration when rendering a correct pathological diagnosis.