Familial Mediterranean fever in Lebanon: mutation spectrum, evidence for cases in Maronites, Greek orthodoxes, Greek catholics, Syriacs and Chiites and for an association between amyloidosis and M694V and M694I mutations

Drug-induced hypersensitivity reactions in a Lebanese outpatient population: A decade-long retrospective analysis (2012-2021)

Background

Drug hypersensitivity reactions (DHRs) are becoming more common as a result of increasing prevalence and case complexity. Allergists and clinical immunologists worldwide are challenged daily to adequately diagnose and manage these reactions. Data in the literature regarding DHR outpatient consultations are scarce worldwide, limited in the Middle East, and currently unavailable in Lebanon.

Objective

This retrospective study aimed to evaluate the characteristics of all reported DHRs over 10 years in a tertiary-care allergy clinic in Lebanon.

Methods

We conducted a decade-long (2012-21) retrospective analysis of the archived medical records of patients with a history of DHRs. Demographics, clinical history, diagnostic tools, and characteristics of the DHRs were collected and analyzed.

Results

A total of 758 patients experienced DHRs to therapeutic molecules provided for ambulatory care. Our results identified 72 medications. The most frequently implicated drug classes included β-lactam antibiotics (53.8%), followed closely by nonsteroidal anti-inflammatory drugs (48.9%). Of the 758 patients, 32.6% reported DHRs to multiple molecules, and 11.8% reported concomitant DHRs to 1 or several molecules provided in the perioperative setting. Of those, opioids and neuromuscular blocking agents were the 2 most common therapeutic classes. Furthermore, we evaluated the cross-reactivity between molecules of the same class. In neuromuscular blocking agents, rocuronium and cisatracurium were the most commonly cross-reactive, and for opioids, the most common association we recorded was with morphine and pethidine.

Conclusion

Our findings constitute the first step toward a more comprehensive evaluation of the clinical characteristics of DHRs in Lebanon.

Familial Mediterranean fever and microRNAs

Familial Mediterranean fever (FMF) is an inherited disorder caused by the gain of function mutations in MEFV (MEditerranean FeVer) gene loci. FMF affects more than 100,000 people worldwide and generally seen in the eastern Mediterranean region and causes the lifelong diseases which have a significant effect on the patient's life quality and health systems. The identification of low penetrant or heterozygous MEFV gene mutations in clinically diagnosed FMF patients was considered that epigenetic or environmental factors may display a role in FMF pathogenesis. Epigenetics might be defined as heritable changes that affect gene expression without any changes in the genome. MicroRNAs (miRNAs) are the main group of small noncoding RNAs, and an important element of epigenetic mechanisms and their discoveries revolutionized our knowledge about biological processes, such as malignant, infectious and autoimmune mechanisms, and contributed to the development of the epigenetic areas. In this review, the studies focusing on the roles of miRNAs in FMF pathogenesis in the last decades were examined and the importance of miRNAs as therapeutic agents which are promising for diagnosis and treatment was discussed.

Assessment of Surrogate Markers for Cardiovascular Disease in Familial Mediterranean Fever-Related Amyloidosis Patients Homozygous for M694V Mutation in MEFV Gene

Cardiovascular disease (CVD) remains underestimated in familial Mediterranean fever-associated AA amyloidosis (FMF-AA). We aimed to compare early markers of endothelial dysfunction and atherosclerosis in FMF-AA with a homozygous M694V mutation (Group 1 = 76 patients) in the Mediterranean fever (MEFV) gene and in patients with other genotypes (Group 2 = 93 patients). Measures of increased risk for future CVD events and endothelial dysfunction, including flow-mediated dilatation (FMD), pentraxin-3 (PTX3), and carotid intima-media thickness (cIMT), and fibroblast growth factor 23 (FGF23) as a marker of atherosclerotic vascular disease were compared between groups. The frequency of clinical FMF manifestations did not differ between the two groups apart from arthritis (76.3% in Group 1 and 59.1% in Group 2, p < 0.05). FMD was significantly lower in Group 1 when compared with Group 2 (MD [95% CI]: −0.6 [(−0.89)−(−0.31)]). cIMT, FGF23, and PTX3 levels were higher in Group 1 (cIMT MD [95% CI]: 0.12 [0.08−0.16]; FGF23 MD [95% CI]: 12.8 [5.9−19.6]; PTX3 MD [95% CI]: 13.3 [8.9−17.5]). In patients with FMF-AA, M694V homozygosity is associated with lower FMD values and higher cIMT, FGF23, and PTX3 levels, suggesting increased CVD risk profiles. These data suggest that a genotype−phenotype association exists in terms of endothelial dysfunction and atherosclerosis in patients with FMF-AA.

Genotype-phenotype associations in familial Mediterranean fever: a study of 500 Egyptian pediatric patients

INTRODUCTION

Familial Mediterranean fever (FMF) is the most prevalent monogenic autoinflammatory disease, caused by recessively inherited MEFV gene mutations. The most frequent MEFV mutations differ in penetrance and disease severity. We investigated the genotype-phenotype associations of the three most frequent MEFV gene mutations (M680I, M694V, and V726A) in Egyptian FMF children, regarding clinical features, severity, and colchicine response.

METHODS

We conducted a retrospective analysis of the medical registries of 500 FMF pediatric patients from Metropolitan Cairo between 2010 and 2015. The diagnosis was based on the Tel-Hashomer clinical diagnostic criteria. Clinical data and baseline investigations were collected. Mutation analysis was performed by the amplification-refractory mutation system (ARMS)-PCR method.

RESULTS

Males represented 54% and ages ranged from 2 to 18 years. The most frequent symptoms were abdominal pain, fever, and arthralgia. Clinical features mostly associated with M694V mutation either homozygous or heterozygous whether simple, double, or triple. Of the patients, 94.6% completely responded to colchicine. Among patients benefiting from colchicine, 42.5% had M694V/V726A, 21.6% had M694V/V726A/M680I, and 21.1% had M694V genotype. Simple heterozygous M694V or V726A mutations conveyed a moderate phenotype in 57.1% and 50% of cases, respectively. Homozygous M694V mutation showed moderate and severe phenotypes in 21.7% and 65.2% of cases, respectively. Compound M694V/V726A mutation associated with moderate or severe disease in 48.3% and 33.8% of cases, respectively.

CONCLUSION

This study encompasses the largest group of Egyptian pediatric FMF up to date to explore their genotype-phenotype associations. Our results support the notion that the genotype influences the phenotype as regards clinical manifestations, disease severity, and colchicine response.

KEY POINTS

• This study encompasses the largest group of Egyptian pediatric patients affected by FMF up to date to explore their genotype-phenotype associations. • Our results support the notion that the genotype influences the phenotype as regards the clinical manifestations, the disease severity, and the response to colchicine treatment.

Spectrum of MEFV Variants and Genotypes among Clinically Diagnosed FMF Patients from Southern Lebanon

Background: Familial Mediterranean Fever (FMF) is an autosomal recessive auto-inflammatory disease characterized by pathogenic variants in the MEFV gene, with allele frequencies greatly varying between countries, populations and ethnic groups. Materials and methods: In order to analyze the spectrum of MEFV variants and genotypes among clinically diagnosed FMF patients from South Lebanon, data were collected from 332 participants and 23 MEFV variants were screened using a Real-Time PCR Kit. Results: The mean age at symptom onset was 17.31 ± 13.82 years. The most prevalent symptoms were abdominal pain, fever and myalgia. MEFV molecular analysis showed that 111 patients (63.79%) were heterozygous, 16 (9.20%) were homozygous, and 47 (27.01%) carried two variants or more. E148Q was the most encountered variant among heterozygous subjects. E148Q/M694V was the most frequent in the compound heterozygous/complex genotype group, while M694I was the most common among homozygous patients. Regarding allele frequencies, M694V was the most common variant (20.7%), followed by E148Q (17.1%), V726A (15.7%) and M694I (13.2%). Conclusion: The high percentage of heterozygous patients clinically diagnosed as FMF highlights the pseudo-dominant transmission of the disease in Lebanon and emphasizes the importance of molecular testing for a more accurate diagnosis and better management and treatment of FMF.

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.

Effects of mating patterns on genealogical trees: Assessment of the high carrier rate of Familial Mediterranean Fever in rural Israeli districts

We investigate the spread from ancestors to descendants, under a model of sexual reproduction, of hereditary elements distinguishing individuals from their fellow human beings. These hereditary elements, termed labels, are either symbolic, implying a socio-cultural or ethnic self-determined category, or biological, i.e. a DNA sequence (for example founder mutations). The impact of various modes of preferential (assortative) mating on the dissemination of a known ancestral label was studied for both kinds of labels, the symbolic and the biological. For the socio-cultural based labeling, both mathematical modeling and simulation studies were carried out, and disclosed a marked delay in the spread of the labels in future generations, compared to the case where mating was random. The transmission of biological labels (founder mutations) from an ancestor to descendants under various modes and degrees of assortative mating was investigated by simulations and supplemented by an in-depth analysis of allele frequencies of Familial Mediterranean Fever (FMF) in an Israeli Muslim Arab village. The high carrier frequency of FMF in this village was satisfactorily explained solely by the presence of a founder effect and a pronounced high factor of selective mating, causing segregation and consanguinity among its inhabitants. Contribution of further evolutionary mechanisms such as heterozygote advantage, drift, differential reproductive success or selection pressure was not essential to explain these results.

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.

The Psychological Attitude of Patients toward Health Practitioners in Lebanon

BACKGROUND

Patients often complain about their doctor's attitude toward them. They describe the interaction that they have with some doctors as quick, cold, discourteous, or hardhearted. Although this does not apply to all Lebanese doctors, it does apply to some.

AIMS

The purpose of this study was to (1) examine the general perception of satisfaction, trust, and openness that Lebanese patients hold toward the work, office, personal, and social characteristics of their doctors - physician or dentist; and (2) identify the aspects on which a Lebanese health practitioner should focus to improve his/her practice.

MATERIALS AND METHODS

A convenient sample of 450 individuals from an area housing nine hospitals and hundreds of private clinics in Greater Beirut were surveyed regarding the qualities of their health practitioners. They were asked to complete a nine-page, 85-item, anonymous, and voluntary questionnaire that dealt with the medical and dental practice in Lebanon. Participants were older than 18 years and mentally competent. None was physicians, dentists, or nurses. The questionnaire was open-ended and initially pretested and piloted among a random sample.

RESULTS

Four hundred-fifteen (92%) individuals responded. Participants were from different ages, genders, geographical areas, educational backgrounds, and professions. The doctor traits most preferred by the Lebanese public were found to be: Empathy (90%), professionalism (87%), miscellaneous traits (86%), and academics (81%).

CONCLUSION

The results support the conventional wisdom that the idealized perception of a doctor as a care-giving, compassionate, knowledgeable, well-appearing, and healthy role model still holds true within the Lebanese community.

The ABCC6 Transporter as a Paradigm for Networking from an Orphan Disease to Complex Disorders

The knowledge on the genetic etiology of complex disorders largely results from the study of rare monogenic disorders. Often these common and rare diseases show phenotypic overlap, though monogenic diseases generally have a more extreme symptomatology. ABCC6, the gene responsible for pseudoxanthoma elasticum, an autosomal recessive ectopic mineralization disorder, can be considered a paradigm gene with relevance that reaches far beyond this enigmatic orphan disease. Indeed, common traits such as chronic kidney disease or cardiovascular disorders have been linked to the ABCC6 gene. While during the last decade the awareness of the wide ramifications of ABCC6 has increased significantly, the gene itself and the transmembrane transporter it encodes have not unveiled all of the mysteries that surround them. To gain more insights, multiple approaches are being used including next-generation sequencing, computational methods, and various "omics" technologies. Much effort is made to place the vast amount of data that is gathered in an integrated system-biological network; the involvement of ABCC6 in common disorders provides a good view on the wide implications and potential of such a network. In this review, we summarize the network approaches used to study ABCC6 and the role of this gene in several complex diseases.

The inflammasomes and autoinflammatory syndromes

Inflammation, a vital response of the immune system to infection and damage to tissues, can be initiated by various germline-encoded innate immune-signaling receptors. Among these, the inflammasomes are critical for activation of the potent proinflammatory interleukin-1 cytokine family. Additionally, inflammasomes can trigger and maintain inflammatory responses aimed toward excess nutrients and the numerous danger signals that appear in a variety of chronic inflammatory diseases. We discuss our understanding of how inflammasomes assemble to trigger caspase-1 activation and subsequent cytokine release, describe how genetic mutations in inflammasome-related genes lead to autoinflammatory syndromes, and review the contribution of inflammasome activation to various pathologies arising from metabolic dysfunction. Insights into the mechanisms that govern inflammasome activation will help in the development of novel therapeutic strategies, not only for managing genetic diseases associated with overactive inflammasomes, but also for treating common metabolic diseases for which effective therapies are currently lacking.

A review of the diverse genetic disorders in the Lebanese population: highlighting the urgency for community genetic services

The review lists the genetic diseases reported in Lebanese individuals, surveys genetic programs and services, and highlights the absence of basic genetic health services at the individual and community level. The incidence of individual diseases is not determined, yet the variety of genetic diseases reported is tremendous, most of which follow autosomal recessive inheritance reflecting the social norms in the population, including high rates of consanguinity, which favor the increase in incidence of these diseases. Genetic services including all activities for the diagnosis, care, and prevention of genetic diseases at community level are extremely inadequate. Services are limited to some clinical and laboratory diagnostic services with no genetic counseling. These services are localized within the capital thus preventing their accessibility to high-risk communities. Screening programs, which are at the core of public health prevention services, are minimal and not nationally mandated. The absence of adequate genetic services is attributed to many factors undermining the importance of genetic diseases and their burden on society, the most important of which is genetic illiteracy at all levels of the population, including high-risk families, the general public, and most importantly health care providers and public health officials. Thus, a country like Lebanon, where genetic diseases are expected to be highly prevalent, is in utmost need for community genetics services. Strategies need to be developed to familiarize public health officials and medical professionals with medical genetics leading to a public health infrastructure that delivers community genetics services for the prevention and care of genetic disorders at community level.

Prevalence of known mutations and a novel missense mutation (M694K) in the MEFV gene in a population from the Eastern Anatolia Region of Turkey

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever and serositis. Mutations in the Mediterranean fever gene (MEFV) localized on the short arm of chromosome 16 cause FMF. Over 90 MEFV missense/nonsense mutations have been identified so far in FMF patients, mostly in the 10th exon of the gene. In this study, the molecular test results of 891 patients identified as having FMF clinical symptoms referred to Molecular Genetics Laboratory of the Department of Medical Biology and Genetics, Faculty of Medicine, Inonu University, Malatya/Turkey were retrospectively evaluated. Patients were referred by their physicians for MEFV mutation detection. The DNA fragments including hot spots within the coding sequences of the MEFV gene were amplified by PCR using genomic DNA and analyzed by pyrosequencing technique. Of the 891 patients investigated, 420 (47.13%) had at least one mutation. The most frequent mutation was E148Q, followed by M694V, M680I (G/C), P369S, V726A, R761H, A744S, M694I, K695R and F479L mutations. In addition, a novel missense mutation (M694K) was reported in seven members of a family in the course of mutation screening of patients.

Familial Mediterranean fever in a large Lebanese family: multiple MEFV mutations and evidence for a Founder effect of the p.[M694I] mutation

Familial Mediterranean fever (FMF) is an autoinflammatory autosomal recessive disease characterized by recurrent fever crises and serous inflammation. The MEFV gene responsible for the disease was identified on chromosome 16, and 5 of the mutations discovered so far in the gene are most frequently encountered in FMF patients: p.[M694V], p.[V726A], p.[M680I] and p.[M694I] in exon 10, and p.[E148Q] in exon 2. The present work describes multiple MEFV mutations and the corresponding haplotypes for 31 FMF patients as well as 32 "healthy" individuals of a large consanguineous Lebanese family. The DNAs were screened for MEFV mutations, and determination of the corresponding haplotypes was performed for all individuals by genotyping 4 microsatellites surrounding the gene. Five different mutations were detected in this one family, which is unexpected in such a genetic isolate. A phenotypic variability was also observed. The haplotype carrying the p.[M694I] allele, detected in all the family branches, was well conserved and therefore seems to be the ancestral one.

Population genetic data for 17 STR markers from Lebanon

Seventeen autosomal STRs were analyzed (D2S1338, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D19S433, D21S11, CSF1PO, FGA, TH01, TPOX, vWA, Penta D, and Penta E) in the Lebanese population. A total of 192 unrelated individuals were genotyped for the 15 autosomal STRs in the Promega PowerPlex 16 STR kit. An additional 275 unrelated individuals were genotyped for the Applied Biosystems AmpFlSTR Identifiler and SGM+STR kits. Allele frequencies for the shared CODIS 13 loci among the three STR kits tested were not significantly different among individuals within the Lebanese population. Forensic and population genetic parameters for the 17 loci were calculated. We also compared the allele frequencies from this population with other populations in the same geographic vicinity.

Periodontal disease in patients with familial Mediterranean fever: from inflammation to amyloidosis

BACKGROUND AND OBJECTIVE

Familial Mediterranean fever stimulates a very intense acute-phase reactants response and if left untreated eventually leads to amyloidosis. The aim of this study was to determine the prevalence of periodontal disease among patients with familial Mediterranean fever in the Black Sea region in Turkey and to evaluate whether periodontitis is related to amyloidosis in patients with familial Mediterranean fever.

MATERIAL AND METHODS

One-hundred and thirty three patients with familial Mediterranean fever and 50 healthy subjects were included in this study. Periodontal health and disease were evaluated using the gingival index, papillary bleeding index, plaque index and periodontal disease index. The concentrations of serum acute-phase reactants were measured at baseline and at 4-6 wk after completion of the nonsurgical periodontal therapy. Genetic testing for familial Mediterranean fever was performed using the familial Mediterranean fever StripAssay. Kidney biopsy was carried out on all proteinuric patients.

RESULTS

The prevalence of moderate to severe periodontitis in familial Mediterranean fever patients with amyloidosis (80.6%) was significantly greater (p < 0.01) than in familial Mediterranean fever patients without amyloidosis (38%) and in controls (20%). Serum levels of acute-phase reactants in familial Mediterranean fever patients were reduced significantly following nonsurgical periodontal therapy (p < 0.01).

CONCLUSION

Periodontal therapy seems to reduce the serum levels of acute-phase reactants in patients with familial Mediterranean fever. Therefore, treating periodontitis might help to alleviate the disease burden in patients with familial Mediterranean fever.

Expression of ASC in renal tissues of familial mediterranean fever patients with amyloidosis: postulating a role for ASC in AA type amyloid deposition

Familial Mediterranean fever (FMF) is characterized by recurrent attacks of fever and serositis; in some cases, ensuing amyloidosis results in kidney damage. Treatment with colchicine reduces the frequency and severity of FMF attacks and prevents amyloidosis, although the mechanisms behind these effects are unknown. Pyrin, the protein product of the MEFV gene, interacts with ASC, a key molecule in apoptotic and inflammatory processes. ASC forms intracellular speck-like aggregates that presage cell death. Here we show that cell death after ASC speck formation is much slower in nonmyeloid cells than in myeloid cells. Additionally, we demonstrate that colchicine prevents speck formation and show that specks can survive in the extracellular space after cell death. Because we also found that ASC is expressed in renal glomeruli of patients with FMF but not in those of control patients, we posit that high local ASC expression may result in speck formation and that specks from dying cells may persist in the extracellular space where they have the potential (perhaps in association with pyrin) to nucleate amyloid. The fact that speck formation requires an intact microtubule network as shown here could potentially account for the ability of prophylactic colchicine to prevent or reverse amyloidosis in patients with FMF.

Comparison of the results of PCR-RFLP and reverse hybridization methods used in molecular diagnosis of FMF

Familial Mediterranean fever (FMF) is characterized by recurrent fever, serositis, and arthritis. Due to the abundance of mutations and clinical heterogeneity of the disease, different screening methods have been developed. In this study, we aimed to compare our findings of mutations determined by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) with reverse hybridization (RH) methods. In 152 of 263 patients (57.79%) different mutations were determined with RH. Allelic frequencies were E148Q 6.84%, M680I(G/C) 3.61%, M694V 20.91%, V726A 7.03%, P369S 1.33%, F479L 0.19%, M680I(G/A) 0.76%, M694I 0.57%, K695R 0.57%, A744S 0.38%, R731H 0.38%, and del1692 0%. Frequent mutations were also confirmed by PCR-RFLP. There were no conflicting results between the two methods. Four of these genotypes were homozygous for a single mutation, 15 were heterozygous for two mutations, 8 were heterozygous for a single mutation, 1 was heterozygous for three mutations, and 1 was homozygous for one mutation and heterozygous for another mutation. It has been reported that analytical sensitivity of RH is 97%. We did not find a discrepancy between the two methods. In 21 patients, we detected additional mutations with RH. This finding was regarded as an advantage of RH, and we concluded that this assay is a useful method for detection of first stage FMF mutation screening.

MEFV gene mutations spectrum among Lebanese patients referred for Familial Mediterranean Fever work-up: Experience of a major tertiary care center

Familial Mediterranean Fever (FMF) is an autosomal recessive inflammatory disorder predominantly affecting people living in or originating from areas around the Mediterranean Sea, mainly Jews, Armenians, Turks, and Arabs. It is characterized by recurrent attacks of inflammation of serosal membranes and fever resulting in acute abdominal, chest, or joint pain. Over 50 MEditerranean FeVer (MEFV) mutations and polymorphisms have been identified in FMF patients. The objective of this study was to analyze the distribution and frequencies of 12 MEFV mutations in 266 referred Lebanese patients using a reverse-hybridization assay. Of the 266 patients, 129 (48.5%) were positive for at least one mutation and 137 (51.5%) had no mutations detected. Of the 129 patients with mutations, 35 were homozygous, 41 were compound heterozygous and 53 were heterozygous. The five most common mutations M694V, E148Q, V726A, M694I and M680I (G/C) accounted for 26.1, 22.2, 21.3, 9.6 and 7.7%, respectively. The A744S, F479L, R761H and I692del were encountered in 2.9% of patients; P369S and M680I (G/A) were found in 1.2% of patients while K695R was absent. The spectrum of the MEFV mutations among our sampled Lebanese FMF patients shows the high heterogeneity at the allelic level when compared to Arab and non-Arab populations. The most important feature was the relatively high frequency of the E148Q in our study group that allows us to question it as a mutation rather than a polymorphism. Further studies should be conducted to evaluate the role of the E148Q allele.

Population genetics of familial Mediterranean fever: a review

In this review, some principal population genetic features of familial Mediterranean fever (FMF) are considered. These relate to the time and the place of founder mutations' origins, the role of ancient migrations and contacts between populations in the spatial spreading of the disorder, the influence of environmental factors and cultural traditions on the rate of FMF incidence, and possible selective advantage in carriers of FMF causing gene (MEFV) mutations.

MEFV Mutations in Tunisian Patients Suffering from Familial Mediterranean Fever

OBJECTIVES

To identify the frequency and distribution of familial Mediterranean fever (FMF) gene (MEFV) mutations in Tunisian patients.

PATIENTS AND METHODS

This study was performed in the Genetic Department of Tunis University Hospital. A clinical diagnosis of FMF was made according to published criteria. Mutation screening of the MEFV gene was performed in the Human Genetic Laboratory of the "Faculté de Medecine de Tunis" for 8 mutations including the 5 most common known mutations M694V, V726A, M694l, M680l, and E148Q. The tests performed were polymerase chain reaction (PCR) restriction-digestion for M694V, V726A, M680l, R761H, E148Q; amplification refractory mutation system for A744S, M694l; and PCR-electrophoresis assay for l692del.

RESULTS

Of the 139 unrelated patients investigated, 61 (44%) had 1 or 2 mutations. In 78 (56%) probands no mutation was identified: 28 patients were homozygous; 16 were compound-heterozygous; 2 had complex alleles; and 17 had only 1 identifiable mutation. Of the mutations, M680l, M694V, M694l, V726A, A744S, R761H, l692DEL, and E148Q accounted for 32, 27, 13, 5, 3, 1, 1, and 18%, respectively.

CONCLUSION

The profile of the MEFV gene mutations in the Tunisian population is concordant with other Arab populations but with some differences. M680l is the most common mutation, while V726A, the commonest mutation among Arabs, is rare in our population.

Familial Mediterranean fever in the Syrian population: gene mutation frequencies, carrier rates and phenotype–genotype correlation

BACKGROUND

Familial Mediterranean fever (FMF) is an autosomal recessive disease mainly affecting particularly Arabs, Non-Ashkenazi Jews, Armenians, and Turks. It is an autoinflammatory periodic disorder characterized by febrile and painful attacks due to inflammation involving the serosal membranes in the abdomen, chest or joints. Over 50 mutations have been identified in the MEFV gene responsible for FMF.

OBJECTIVE

To identify the distribution and the frequency of the MEFV gene mutations in Syrian FMF patients and population and perform a genotype/phenotype correlation in the patients' cohort.

PATIENTS AND METHODS

The study was carried out on 83 clinically diagnosed Syrian FMF patients and 242 healthy subjects. The tested individuals were screened for the most common five MEFV mutations (M694V, M694I, M680I, V726A and E148Q) by restriction fragment length polymorphism. Sequencing of exon 10 was performed only for the patients' DNA where just one or no mutation was detected.

RESULTS AND DISCUSSION

Of the 83 patients studied, 74 (89%) were positive either for one, two or three mutations and nine (11%) had no mutations detected. Of those positive for mutations, 25 were homozygous, 30 were compound heterozygotes, three had complex alleles, and 16 patients had only one mutation. The M694V, V726A, M694I, M680I and E148Q mutations accounted for 45.8%, 26%, 13.9%, 4.8% and 6% of the alleles, respectively. The carrier rate in the Syrian population for the tested mutations was 17.5%, E148Q being the most common mutation, followed by V726A and M694V. The severity of the disease and development of amyloidosis seem to have an association with M694V, the most common mutation in Syrian FMF patients.

Familial mediterranean fever in Arabs

Autoinflammatory diseases are a group of disorders characterised by seemingly unprovoked inflammation in the absence of high-titre autoantibodies or antigen-specific T cells, and include the hereditary periodic fever syndromes. Familial Mediterranean fever (FMF) is an archetypal autoinflammatory disorder, which is autosomal recessive and has a high prevalence in non-Ashkenazi Jews, Armenians, Turks, and Arabs. The classic clinical picture is recurrent acute short-lived febrile and painful attacks with variable periods of remission. In a subset of patients, the disorder is complicated by amyloidosis that leads to renal failure. The gene responsible for FMF--MEFV--has been identified and its role in inflammation is being assessed. There seems to be a distinctive clinical picture in Arab patients with FMF, and the range and distribution of MEFV mutations is different from that noted in other affected ethnic groups. Here, we discuss the clinical and molecular aspects of FMF in Arabs.

Familial Mediterranean fever (FMF) in Lebanon and Jordan: a population genetics study and report of three novel mutations

Familial Mediterranean fever (FMF) is an autosomal recessive disease mostly frequent in Mediterranean populations. Over 50 mutations have been identified in the gene responsible for the disease, MEFV. The present study reports the frequencies of MEFV mutations in 558 Lebanese and 55 Jordanian FMF patients and points out the severity of the M694V frequently observed mutation among these patients. Three novel mutations, T177I, S108R and E474K were also identified in the Lebanese group. An excess of homozygotes and a deficit of heterozygotes were observed in both samples when compared to the expected number of observed genotypes under the Hardy-Weinberg hypothesis. Homozygotes for M694V and M694I were still in excess in the Lebanese group of patients, even after consanguinous homozygotes were removed, or population structure was considered. This excess is therefore neither due to consanguinity nor to subgroups in the Lebanese population, but rather to more remote consanguinity or to a selection bias favoring the census of these genotypes. The fact that FMF female patients were less censed than male patients may be due to the greater resistance of females to pain and to the possibility of confusing abdominal and gynecological pain. The phenotypic heterogeneity of the FMF could then originate both from genetic causes like allelic heterogeneity or modulating genes, and cultural background facing the physiological consequences of genotypes at risk.

Familial autoinflammatory diseases: genetics, pathogenesis and treatment

PURPOSE OF REVIEW

The systemic autoinflammatory diseases are characterized by seemingly unprovoked inflammation, without major involvement of the adaptive immune system. This review focuses mainly on a subset of these illnesses, the hereditary recurrent fevers, which include familial Mediterranean fever, the tumor necrosis factor receptor-associated periodic syndrome, the hyperimmunoglobulinemia D with periodic fever syndrome, and cryopyrin-associated periodic syndromes. This review elucidates how recent advances have impacted diagnosis, pathogenesis, and treatment.

RECENT FINDINGS

More than 170 mutations have been identified in the four genes underlying the six hereditary recurrent fevers. Genetic testing has broadened the clinical and geographic boundaries of these illnesses, given rise to the concept of the cryopyrin-associated periodic syndromes as a disease spectrum, and permitted diagnosis of compound heterozygotes for mutations in two different hereditary recurrent fever genes. Genetics has also advanced our understanding of amyloidosis, a complication of the hereditary recurrent fevers, and suggested a possible role for common hereditary recurrent fever variants in other inflammatory conditions. Recent advances in molecular pathophysiology include the elucidation of the N-terminal PYRIN domain in protein-protein interactions, the description of the NALP3 (cryopyrin) inflammasome as a macromolecular complex for interleukin-1beta activation, and the identification of signaling defects other than defective receptor shedding in patients with tumor necrosis factor receptor-associated periodic syndrome. These molecular insights form the conceptual basis for targeted biologic therapies.

SUMMARY

Advances in molecular genetics extend our ability to recognize and treat patients with systemic autoinflammatory diseases and inform our understanding of the regulation of innate immunity in humans.

The Spectrum of Familial Mediterranean Fever Gene Mutations in Arabs: Report of a Large Series

OBJECTIVES

To identify the frequency and distribution of familial Mediterranean fever (FMF) gene (MEFV) mutations in Arab patients.

PATIENTS AND METHODS

The study was performed in the pediatric FMF clinic of Jordan University Hospital over a period of 4 years. Patients were referred by their physicians for diagnosis, management, genetic study, and counseling. A diagnosis of FMF was made according to published criteria. Screening for 5 mutations, namely M694V, V726A, M694I, M680I, and E148Q, was performed by amplification refractory mutation system (ARMS) for the first 4 and by restriction endonuclease testing for E148Q.

RESULTS

Of the 407 unrelated patients investigated, 239 (59%) had 1 or 2 mutations and 168 (41%) had none of the studied mutations detected. Of those with mutations, 92 were homozygous, 53 were compound heterozygotes, 3 had complex alleles, and 91 patients had only 1 identifiable mutation. Of the mutations, M694V, V726A, M694I, M680I, and E148Q accounted for 38, 26, 14, 10 and 13%, respectively. Twelve of our patients developed the protracted febrile myalgia syndrome (PFMS) of whom 5 (42%) were homozygous for M694V. Only 2 developed chronic renal failure, both of whom were homozygous for M694V and were not on colchicine prophylaxis. However, 43 patients had a family history of chronic renal failure, and 15 (35%) were homozygous for M694V.

CONCLUSIONS

Our data indicate that the 5 MEFV mutations are well distributed in Arabs. They also show that M694V is the most common mutation in Arab patients with FMF and seems to have an association with the development of amyloidosis and the PFMS. The high frequency of V726A, and the unique high frequency of M694I in Arabs compared with 3 other ethnic groups, are confirmed.

Familial Mediterranean fever mimicking septic arthritis

We report the case of a young Lebanese female who presented with recurrent episodes of left knee and calf swelling and a synovial fluid leucocyte count suggestive of septic arthritis, however bacteriologic cultures were negative. Familial Mediterranean fever (FMF) was suspected in view of a positive family history and genetic analysis for the mutations in the pyrin/marenostrin (MEFV) gene revealing a homozygote mutation at methionine-694-valine. The arthritis was controlled with prophylactic colchicine therapy. FMF should be considered in the differential diagnosis of acute monoarticular arthritis with elevated synovial fluid white blood cells counts in regions with high incidence of FMF.

Familial Mediterranean Fever and E148Q Pyrin Gene Mutation in Greece

Familial Mediterranean fever (FMF) is an inherited disease characterized by recurrent inflammatory polyserositis. Although FMF is classically expected only in Middle East populations, it is becoming evident that the disease affects more groups than initially thought. The disease is associated with a number of mutations of the MEFV gene, which codes for a protein named pyrin. The role of E148Q pyrin gene mutation in the development of FMF remains inconclusive. Some authors believe it causes the disease, whereas others favor the concept of a noncausative role. To understand better the role of this mutation, gathering data from different populations may be of value. We studied 60 Greek cases fulfilling the criteria for FMF diagnosis, 30 cases being a definite FMF diagnosis and 30 a probable diagnosis. Twenty-one of the patients, carried mutation E148Q. One was a homozygote (E148Q/E148Q), and 20 carried mutation E148Q in combination with other mutations (compound heterozygotes). In 6 of the 60 cases studied, no mutations were found. Compared with the results for healthy controls, E148Q mutation is significantly frequent. Because different populations may exhibit different patterns of pyrin mutations, association of the E148Q mutation with FMF should be considered in connection with origin data.

Familial Mediterranean fever (FMF) in Turkey: results of a nationwide multicenter study

Familial Mediterranean fever (FMF) is an autosomal recessive disease that is prevalent among eastern Mediterranean populations, mainly non-Ashkenazi Jews, Armenians, Turks, and Arabs. Since a large proportion of all the FMF patients in the world live in Turkey, the Turkish FMF Study Group (FMF-TR) was founded to develop a patient registry database and analyze demographic, clinical, and genetic features. The cohort was composed of 2838 patients (mean age, 23.0 +/- 13.33 yr; range, 2-87 yr), with a male:female ratio of 1.2:1. There was a mean period of 6.9 +/- 7.65 years from disease onset to diagnosis; the period was about 2 years shorter for each decade since 1981. Ninety-four percent of patients were living in the central-western parts of the country; however, their familial origins (70% from the central-eastern and Black Sea regions) reflected not only the ongoing east to west migration, but also the historical roots of FMF in Turkey. Patients' clinical features included peritonitis (93.7%), fever (92.5%), arthritis (47.4%), pleuritis (31.2%), myalgia (39.6%), and erysipelas-like erythema (20.9%). Arthritis, arthralgia, myalgia, and erysipelas-like erythema were significantly more frequent (p < 0.001) among patients with disease onset before the age of 18 years. Genetic analysis of 1090 patients revealed that M694V was the most frequent mutation (51.4%), followed by M680I (14.4%) and V726A (8.6%). Patients with the M694V/M694V genotype were found to have an earlier age of onset and higher frequencies of arthritis and arthralgia compared with the other groups (both p < 0.001). In contrast to other reported studies, there was no correlation between amyloidosis and M694V homozygosity in this cohort. However, amyloidosis was still remarkably frequent in our patients (12.9%), and it was prevalent (27.8%) even among the 18 patients with a disease onset after age 40 years. Twenty-two patients (0.8%) had nonamyloid glomerular diseases. The high prevalence of vasculitides (0.9% for polyarteritis nodosa and 2.7% for Henoch-Schonlein purpura) and high frequency of pericarditis (1.4%) were striking findings in the cohort. Phenotype II cases (those patients with amyloidosis as the presenting or only manifestation of disease) were rare (0.3% or less). There was a high rate of a past diagnosis of acute rheumatic fever, which suggested a possible misdiagnosis in children with FMF presenting with recurrent arthritis. To our knowledge, this is the largest series of patients with FMF reported from 1 country. We describe the features of the disease in the Turkish population and show that amyloidosis is still a substantial problem.

Reverse-Hybridization vs. DNA Sequencing in the Molecular Diagnosis of Familial Mediterranean Fever

Familial Mediterranean fever (FMF) is an autosomal recessive inflammatory disorder predominantly affecting people living in or originating from areas around the Mediterranean Sea. It is caused by a number of mutations within the MEFV gene, which differently affect the severity of the disease phenotype. Because patients usually present with rather nonspecific clinical symptoms, MEFV genotyping can confirm and refine FMF diagnosis and improve treatment of affected individuals. We have performed a method comparison study on 100 Lebanese FMF patients to evaluate the potential of a rapid reverse-hybridization teststrip-based assay (FMF StripAssay) to serve as a first-line screening test for our population. When results obtained by reverse-hybridization and DNA sequencing of exons 2, 3, 5, and 10 were compared, the FMF StripAssay identified 144/149 mutations, and correctly typed all 12 different MEFV mutations covered. We conclude that reverse-hybridization provides a very rapid, accurate and easy-to-perform screening method, and, in combination with more comprehensive diagnostic methods, represents an efficient strategy for FMF genotyping.

Amyloidosis in familial Mediterranean fever patients: correlation with MEFV genotype and SAA1 and MICA polymorphisms effects

Background

Familial mediterranean fever (FMF) is a recessively inherited disease characterized by recurrent crises of fever, abdominal, articular and/or thoracic pain. The most severe complication is the development of renal amyloidosis. Over 35 mutations have been discovered so far in the gene responsible for the disease, MEFV. This article aims at determining a correlation between the MEFV genotype and the occurence of amyloidosis in FMF patients, in addition to the study of the modifying effects of the SAA1 (type 1 serum amyloid A protein) and MICA (Major Histocompatibility Complex (MHC) class-I-chain-related gene A) genes on this severe complication.

Methods

Fourteen MEFV mutations were screened and the SAA1 and MICA polymorphisms tested in 30 FMF patients with amyloidosis and 40 FMF patients without amyloidosis.

Results

The M694V and V726A allelic frequencies were, respectively, significantly higher and lower in the group with amyloidosis, compared to the control FMF group. The beta and gamma SAA1 alleles were more frequently encountered in the group without amyloidosis, whereas the alpha allele was significantly more observed in FMF patients with amyloidosis (p < 0.025). All the MICA alleles were encountered in both patients' groups, but none of them was significantly associated with amyloidosis.

Conclusions

The results suggest a protective effect of the SAA1 beta and gamma alleles on the development of amyloidosis and show the absence of a MICA modifying effect on amyloidosis development. Testing these polymorphisms on a larger sample will lead to more definite conclusions.

Familial Mediterranean fever with amyloidosis associated with novel exon 2 mutation (S1791) of the MEFV gene

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever, serositis, and a risk for AA amyloidosis. FMF is caused by mutations in the Mediterranean fever gene (MEFV), which is expressed in blood cells of the myelomonocytic differentiation pathway. We identified a novel mutation S1791 in exon 2 of MEFV in two members of a family of Turkish origin. In both cases, S1791 was in compound heterozygosity with MEFV mutation M694V, and the characteristic clinical syndrome of FMF including amyloidosis was found. The location of S1791 in exon 2 is of interest because (1) amyloidosis in FMF has previously been found to be strongly associated with compound exon 10 mutations and (2) it supports the notion that the mechanism causing FMF is connected to the cytoplasmic rather than nuclear function of the molecule.

Familial Mediterranean fever (FMF) mutations occur frequently in the Greek-Cypriot population of Cyprus

Familial Mediterranean Fever (FMF) is an autosomal recessive disease of high prevalence within Mediterranean countries and particularly common in four ethnic populations: Arabs, non-Ashkenazi Jews, Armenians, and Turks. The responsible gene MEFV has been assigned to chromosome 16p13.3. Our aim was to establish the frequencies of the most common mutations in Greek-Cypriots. We found that 1 in 25 is a carrier of one of three mutations. V726A, M694V, and F479L. In 68 Grek-Cypriot FMF chromosomes analyzed, we found V726A (25%), F479L (20.6%), M694V (17.6%), and others (36.8%). Mutation F479L, relatively common in this population, is very rare elsewhere. Our study indicates that FMF is not a rare condition in Cyprus and that, because of the significant morbidity associated with this disorder, which is often diagnosed only after unnecessary surgeries, a newborn screening program to detect affected in this population may be warranted.

The significance of paired MEFV mutations in individuals without symptoms of familial Mediterranean fever

The majority of patients with familial Mediterranean fever (FMF) have identifiable mutations in both alleles of the MEFV gene, while some individuals with paired MEFV mutations do not have clinical symptoms of the disease. During family studies we identified nine such individuals from six kindreds, most of whom either subsequently developed FMF or had other clinically significant inflammatory disease; one case benefiting substantially from colchicine therapy. Four individuals remained asymptomatic. Two further asymptomatic subjects with paired MEFV mutations were identified among 49 healthy controls from western Turkey, of whom a further 18.4 per cent were simple heterozygotes. This carrier rate was higher than would be expected from prevalence of FMF in this region, suggesting that penetrance of paired recognised pathogenic MEFV mutations may frequently be incomplete. MEFV genotyping results must be interpreted with due caution, and follow-up of apparently asymptomatic subjects with paired mutations is advisable.

Familial Mediterranean Fever: association of elevated IgD plasma levels with specific MEFV mutations

Familial Mediterranean Fever (FMF) is a recessively inherited disorder, characterized by episodic fever, abdominal and arthritic pain, as well as other forms of inflammation. Some FMF patients present higher IgD serum levels, and it is not yet known whether such an elevation is related to specific genotypes or correlated with a specific phenotype. In order to evaluate the association between known FMF-related mutations and IgD levels in confirmed patients, as well as the correlation between those levels and the presence of specific clinical signs, genotypic analysis and IgD plasma measurements were performed for 148 Lebanese and Jordanian FMF patients. Most common mutational patterns were M694V heterozygotes (19%) and homozygotes (17%), and V726A heterozygotes (18%) and homozygotes (5%), with an additional 11% combining both mutations. Twenty-one patients had higher IgD levels (superior to 100 microg/ml). The risk for higher IgD levels was significantly associated with M694V homozygote status (OR = 6.25) but not with heterozygotic one (OR = 1). Similarly, the risk for higher IgD was also found with V726A homozygotes (OR = 2.2) but not with heterozygotes (OR = 1.05). The use of colchicine was not statistically associated with IgD levels. Clinically, hyper IgD was also found significantly associated with arthritis (OR = 18). Thus, homozygotic status for M694V, and to a lesser extent V726A, is associated with increased risk for higher IgD plasma levels, regardless of colchicine use. Elevated IgD plasma levels are also correlated with the severity of FMF manifestations, and especially with arthritis.

The spectrum of Familial Mediterranean Fever (FMF) mutations

Familial Mediterranean Fever (FMF) is the prototype of a group of inherited inflammatory disorders. The gene (MEFV) responsible for this disease, comprises 10 exons and 781 codons. Twenty-nine mutations, most located in the last exon, have been identified so far. It is unclear whether all are true disease-causing mutations. Five founder mutations, V726A, M694V, M694I, M680I and E148Q account for 74% of FMF chromosomes from typical cases (Armenians, Arabs, Jews, and Turks). Rare mutations are preferentially found in populations not usually affected by FMF (eg Europeans not from the above ancestries). The various combinations of MEFV mutations define severe to mild genotypes. The trend is that genotypes including two mutations located within mutational 'hot-spots' (codons 680 or 694) of the gene are associated with severe phenotypes, whereas mild phenotypes are associated with some other mutations, E148Q being the mildest and least penetrant. Understanding the correlation between the FMF phenotype and genotype is further obscured by the existence of complex alleles, modifier loci, genetic heterogeneity and possible epigenetic factors. Additionally, mutations in the MEFV gene are thought to be involved in non FMF disorders. Carrier rates for FMF mutations may be as high as 1:3 in some populations, suggesting that the disease is underdiagnosed. This review update emphasises that both clinical and genetic features are to be taken into account for patient diagnosis, colchicine treatment and prognosis.