Mutation and haplotype studies of familial Mediterranean fever reveal new ancestral relationships and evidence for a high carrier frequency with reduced penetrance in the Ashkenazi Jewish population

Next generation sequencing (NGS)-based approach to diagnosing Algerian patients with suspected inborn errors of immunity (IEIs)

The advent of next-generation sequencing (NGS) technologies has greatly expanded our understanding of both the clinical spectra and genetic landscape of inborn errors of immunity (IEIs). Endogamous populations may be enriched for unique, ancestry-specific disease-causing variants, a consideration that significantly impacts molecular testing and analysis strategies. Herein, we report on the application of a 2-step NGS-based testing approach beginning with targeted gene panels (TGPs) tailored to specific IEI subtypes and reflexing to whole exome sequencing (WES) if negative for Northwest Algerian patients with suspected IEIs. Our overall diagnostic yield of 57% is comparable to others broadly applying short-read NGS to IEI detection, but data from our localized cohort show some similarities and differences from NGS studies performed on larger regional IEI cohorts. This suggests the importance of tailoring diagnostic strategies to local demographics and needs, but also highlights ongoing concerns inherent to the application of genomics for clinical IEI diagnostics.

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.

Explanations for the discrepancy between variant frequency and homozygous disease occurrence: Lessons from Ashkenazi Jewish data

Ample data on recessive disorders among Ashkenazi Jews has been gathered and published through the years. The opportunity to integrate molecular records analyzed in actual affected individuals with data derived from population-documented frequencies enables to compare these figures. We reviewed assumed pathogenic variants reported among patients in the Israeli medical genetic database (IMGD) with a carrier frequency of 1% or more among Ashkenazi Jews in gnomAD. Among the 60 assumed pathogenic variants recorded in IMGD, 15 (25%) had either a disease incidence considerably lower than expected by the calculated carrier frequency (12 variants), or the variant was not characterized in Ashkenazi Jewish patients (three variants). Possible explanations for the rarity or absence of affected individuals despite high carrier frequency include embryonic lethality, clinical variability, and incomplete and age-related penetrance, in addition to the existence of additional assumed pathogenic variants on the founder haplotype, hypomorphic variants or digenic inheritance. The discrepancy in actual versus expected number of patients calls for caution upon designing and choosing targeted genes and recessive mutations for carrier screening.

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.

In this Review, the authors summarize the pathophysiological mechanisms of IL-1-mediated autoinflammation. They describe the epidemiological and clinical features of autoinflammatory diseases, challenges associated with diagnostics and disease management, and current and future therapies for targeting the IL-1 pathway.

IL-1α, IL-1β and IL-1RA are highly regulated inflammatory mediators involved in damage- and pathogen-associated molecular pattern (DAMPs and PAMPs), and cell death pathways.

Patients with evidence of systemic inflammation without persistent infection or autoantibodies should raise suspicion of an IL-1-mediated autoinflammatory disorder.

Rare monogenic and common polygenic diseases with neutrophilia and inflammation might respond to targeting the IL-1 pathway.

Genetic testing confirms IL-1-driven autoinflammatory disorders, yet new disease phenotype–genotype correlations continue to be identified.

IL-1-targeted therapies are highly effective and safe; new therapeutics focus on targets independent of IL-1 receptor binding, including NLRP3, caspases, IRAK4 and MK2.

The PRY/SPRY domain of pyrin/TRIM20 interacts with β2-microglobulin to promote inflammasome formation

Pyrin/TRIM20 is expressed in the neutrophils and monocytes/macrophages and regulates caspase-1 activation and interleukin-1β maturation. Although the mutations in the PRY/SPRY domain of pyrin cause familial Mediterranean fever (FMF), the mechanism of how mutated pyrin provokes excessive inflammation in FMF patients is not well understood. The present study investigated the role of pyrin/TRIM20 in inflammation and the pathogenesis of FMF. β₂-Microglobulin (β2MG) was identified as the novel pyrin ligand binding to the PRY/SPRY domain by yeast two-hybrid screenings and co-immunoprecipitation analysis. β2MG was co-localized with pyrin not only in the HEK293 cells overexpressing these proteins but also in the monosodium urate-stimulated human neutrophils in the speck-like structures. The pyrin–β2MG interaction triggered the binding of pyrin and proline–serine–threonine phosphatase interacting protein 1 (PSTPIP1) and then the subsequent recruitment of apoptosis-associated speck-like protein containing caspase recruitment domain (ASC). Caspase-1 p20 subunit, produced by pyrin inflammasome, also interacted with the pyrin PRY/SPRY domain and inhibited the pyrin–β2MG interaction. FMF-associated pyrin mutation M694V did not affect pyrin–β2MG interaction but weakened this inhibition. Our findings suggest that β2MG functions as the pyrin ligand inducing pyrin inflammasome formation and that the FMF-associated pyrin mutations weakened negative feedback of caspase-1 p20 subunit.

Clinical significance of E148Q heterozygous variant in paediatric familial Mediterranean fever

OBJECTIVES

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

METHODS

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

RESULTS

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

CONCLUSION

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

Secondary Amyloidosis Presenting as Ischemic Proctitis

A 49-year-old man presented with abdominal pain and rectal bleeding for two days associated with a 50-pound unintentional weight loss. History was notable for hypertension, chronic kidney disease, obesity, gout, and acute cholecystitis status post cholecystectomy. Computed tomography (CT) of the abdomen and pelvis showed rectal wall thickening. Colonoscopy showed proctitis with superficial ulcerations. In the setting of renal insufficiency, malabsorption, and low-voltage QRS complexes on electrocardiogram (ECG), amyloidosis was considered in the differential diagnosis. Rectal and renal biopsies with subsequent retrospective staining of gallbladder tissue confirmed amyloid deposition. Gastrointestinal involvement of amyloidosis is relatively uncommon. Particularly, amyloid deposition in the gallbladder and rectum is very rare. The development of AA amyloidosis in our patient may have been related to gout, obesity, and the presence of a heterozygous complex variant for the MEFV (familial Mediterranean fever) gene. Awareness of this atypical presentation of amyloidosis is important, as additional staining of biopsy samples is necessary, and diagnosis allows for directed treatment.

History of the Plague: An Ancient Pandemic for the Age of COVID-19

During the fourteenth century, the bubonic plague or Black Death killed more than one third of Europe or 25 million people. Those afflicted died quickly and horribly from an unseen menace, spiking high fevers with suppurative buboes (swellings). Its causative agent is Yersinia pestis, creating recurrent plague cycles from the Bronze Age into modern-day California and Mongolia. Plague remains endemic in Madagascar, Congo, and Peru. This history of medicine review highlights plague events across the centuries. Transmission is by fleas carried on rats, although new theories include via human body lice and infected grain. We discuss symptomatology and treatment options. Pneumonic plague can be weaponized for bioterrorism, highlighting the importance of understanding its clinical syndromes. Carriers of recessive familial Mediterranean fever (FMF) mutations have natural immunity against Y. pestis. During the Black Death, Jews were blamed for the bubonic plague, perhaps because Jews carried FMF mutations and died at lower plague rates than Christians. Blaming minorities for epidemics echoes across history into our current coronavirus pandemic and provides insightful lessons for managing and improving its outcomes.

Effectiveness of Canakinumab Treatment in Colchicine Resistant Familial Mediterranean Fever Cases

Anti-interleukin 1 agents are used successfully in colchicine-resistant or intolerant Familial Mediterranean Fever (FMF) patients. Sixty-five patients with FMF who received canakinumab treatment for at least 6 months due to colchicine resistance or intolerance between 2016 and 2020 in our department were retrospectively analyzed. Canakinumab treatment was given subcutaneously every 4 weeks. After completing monthly canakinumab therapy over 12 months, in patients with complete remission, the dosing interval was extended to every 1.5 months for 6 months, then every 2 months for 6 months, and finally every 3 months for a year. In patients without disease activation, canakinumab treatment was discontinued at the end of 3 years and followed up with colchicine treatment. Patients who had a flare switched to the previous dosing interval. In patients with renal amyloidosis, monthly canakinumab treatment was continued without extending the dose intervals. The mean duration of canakinumab use in our patients was 31.4 ± 10.57 months (6-52 months). The mean age at onset of symptoms was 4.65 ± 3.84 (range, 1-18) years, and the mean age at diagnosis was 5.59 ± 3.9 (range, 4-19) years. Complete remission was achieved in 57 (87.6%) and partial remission in seven (10.7%) patients. One patient was unresponsive to treatment. Canakinumab treatment was discontinued in three patients with complete remission and one patient with drug resistance. Erythrocyte sedimentation rate (ESR) (51.85 ± 15.7 vs. 27.80 ± 13.73 mm/h) and C-reactive protein (CRP) [26 (3-73) vs. 5 (1-48) mg/L] values were compared before and after canakinumab treatment in attack-free periods, a significant decrease was found after canakinumab treatment (p < 0.001, p < 0.001, respectively). Bodyweight Z-scores (respectively -0.80 ± 0.86 vs. -0.49 ± 0.92) were compared, similarly, a statistically significant increase after canakinumab treatment (p < 0.001), but no significant increase in height Z scores (-1.00 ± 0.88 vs. -0.96 ± 0.94) (p = 0.445) was detected. Four patients had FMF-related renal amyloidosis. The decrease in proteinuria with canakinumab treatment was not statistically significant (p = 0.068). Cervical lymphadenitis developed in one and local reactions in two patients. No severe adverse effects requiring discontinuation of canakinumab treatment were observed. Our study showed that canakinumab treatment was highly effective, well-tolerated in pediatric FMF patients, and controlled extension of the canakinumab dose interval was safe.

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

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

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

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

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

Genome sequencing unveils mutational landscape of the familial Mediterranean fever: Potential implications of IL33/ST2 signalling

Familial Mediterranean fever (FMF) is the most common auto-inflammatory disease. It is transmitted as autosomal recessive trait with mutations in MEditerranean FeVer (MEFV) gene. Despite a typical clinical expression, many patients have either a single or no mutation in MEFV. The current work is aimed to revisit the genetic landscape of FMF disease using high-coverage whole genome sequencing. In atypical patients (carrying a single or no mutation in MEFV), we revealed many rare variants in genes associated with auto-inflammatory disorders, and more interestingly, we discovered a novel variant ( a 2.1-Kb deletion) in exon 11 of IL1RL1 gene, present only in patients. To validate and screen this patient-specific variant, a tandem of allele-specific PCR and quantitative real-time PCR was performed in 184 FMF patients and 218 healthy controls and we demonstrated that the novel deletion was absent in controls and was present in more than 19% of patients. This study sheds more light on the mutational landscape of FMF. Our discovery of a disease-specific variant in IL1RL1 gene may constitute a novel genetic marker for FMF. This finding suggesting a potential role of the IL33/ST2 signalling in the disease pathogenicity highlights a new paradigm in FMF pathophysiology.

A HYPOTHETICAL ROLE FOR PLAGUE IN THE SELECTION OF MEFV MUTATION CARRIERS IN THE MEDITERRANEAN AREA

Familial Mediterranean fever (FMF) is the most common autoinflammatory disease associated with mutations in the MEFV gene encoding Pyrin. MEFV mutations are frequent in the Mediterranean region. Increased resistance to an infection endemic to this area could have caused a selective advantage for individuals with MEFV mutations. Recent studies have shown that Pyrin is a part of host defense against microorganisms and it gets activated after sensing Rho GTPase inactivation by bacteria such as Clostridium difficile or Yersinia pestis. However, Yersinia species have another effector molecule, YopM which inhibits Pyrin in addition to RhoA modifiers YopE and YopT. Continuously overactive Pyrin in individuals with MEFV mutations could be a good host defense against Yersinia infections. Y. pestis causes plague, which led to a devastating pandemic in the Mediterranean basin. Thus, plague could be the infection which caused a selective biologic advantage for MEFV mutation carriers in this area.

Whole-exome sequencing in three children with sporadic Blau syndrome, one of them co-presenting with recurrent polyserositis

Blau syndrome (BS) is a rare, chronic autoinflammatory disease with onset before age 4 and mainly characterised by granulomatous arthritis, recurrent uveitis, and skin rash. Sporadic (also known as early-onset sarcoidosis) or familial BS is caused by gain-of-function mutations in the NOD2 gene, which encodes for a multi-task protein that plays a crucial role in the innate immune defense. We report on three Mexican patients clinically diagnosed with BS who exhibited a likely pathogenic variant in NOD2 as revealed by whole-exome sequencing (WES) and Sanger sequencing: two variants (c.1000 C > T/p.Arg334Trp and c.1538 T > C/p.Met513Thr) lie in the ATP/Mg2+ binding site, whereas the other (c.3019dupC/p.Leu1007ProfsTer2) introduces a premature stop codon disrupting the last LRR domain (LRR9) formation; all three variants are consistent with gain-of-function changes. Interestingly, all these patients presented concomitant likely pathogenic variants in other inflammatory disease-related genes, i.e. TLR10, PRR12, MEFV and/or SLC22A5. Although the clinical presentation in these patients included the BS diagnostic triad, overall it was rather heterogeneous. It is plausible that this clinical variability depends partly on the patients' genetic background as suggested by our WES results. After this molecular diagnosis and given the absence of NOD2 mutations (demonstrated in two trios) and related symptoms in the respective parents (confirmed in all trios), patients 1 and 2 were considered to have sporadic BS, while patient 3, a sporadic BS-recurrent polyserositis compound phenotype. Altogether, our observations and findings underscore the overlapping among inflammatory diseases and the importance of determining the underlying genetic cause by high-throughput methods. Likewise, this study further reinforces a pathogenic link between the here found NOD2 variants and BS and envisages potential additive effects from other loci in these, and probably other patients.

Next-generation screening of a panel of genes associated with periodic fever syndromes in patients with Familial Mediterranean Fever and their clinical characteristics

Familial Mediterranean Fever (FMF) is a hereditary fever syndrome that primarily affects Mediterranean populations. For the study, total number of 182 patients with FMF disease were enrolled and screening of a panel of genes , called "fever panel" which comprises 17 genes, was performed. The most common mutations in MEFV gene were homozygous M694V missense mutation (4.3%) and R202Q missense mutation (4.9%). The most common heterozygous mutations were R202Q (26.5%), M694V (25.9%) and E148Q (11.9%). Compound heterozygous and homozygous mutations were also detected. Also, different types of mutations were identified in NOD2, CARD14, NLRP12, NLRP3, NLRP7, IL1RN, LPIN2, TNFRSF1A, MVK and PSTPIP1 genes. Two novel missense variations in the MEFV gene, Gln34Pro and Ile247Val, which have not been previously reported in the databases, were identified. Also, Thr91Ile missense variation in the NOD2 gene, Gly461Cys missense variation in NLRP3 and Tyr732Stop nonsense variation in LPIN2 were firstly identified. The results of the current study suggest that in addition to the MEFV gene which has an important roles in FMF, molecular screening of other genes related to other autoinflammatory diseases might provide support in suspected cases and provide detailed information about the course of the disease.

The effect of genotype on musculoskeletal complaints in patients with familial Mediterranean fever

Objectives: Familial Mediterranean fever (FMF) is an autosomal recessive disease, characterized by recurrent, self limited attacks of fever with serositis. The aim of this study was to describe the frequency of musculoskeletal complaints in children with FMF and to investigate the effect of genotype on these findings.Methods: Files of patients who had been seen in our department (during routine follow-up visits) were retrospectively evaluated. Comparisons regarding musculoskeletal findings were performed between patients with homozygous/compound heterozygous and heterozygous mutations. Thereafter, patients with two mutations were divided into three groups; M694V/M694V, M694V/other mutation, and patients carrying two mutations other than M694V. Patients with single mutation were divided into two groups; M694V and non M694V carriers.Results: The study group comprised 317 FMF patients (170 females) with a mean age of 12.2 ± 5.7 years. Arthralgia (42.6%), leg pain (42.9%), and heel pain (35.6%) were the most common musculoskeletal complaints in children with FMF. Frequency of musculoskeletal findings of the patients who had two mutations did not differ from the patients with single mutations (p > 0.05). Leg and heel pain were more frequently detected in patients with homozygous M694V mutation (p = 0.001). Among patients with heterozygous mutations; children with M694V mutation had more frequently arthralgia, leg, and heel pain (p < 0.05).Conclusions: Musculoskeletal problems were commonly encountered in patients with FMF. Genotype seems to affect the frequency of these problems and M694V mutation is a predisposing factor for musculoskeletal complaints.

Sacroiliitis in Children With Familial Mediterranean Fever

BACKGROUND/OBJECTIVE

Familial Mediterranean fever (FMF) is an autosomal recessive disease, characterized by recurrent, self-limited attacks of fever with serositis. Various diseases were reported to be associated with FMF. The aim of this study was to investigate the frequency and characteristics of sacroiliitis in children with FMF.

METHODS

Files of FMF patients who had been seen in 2 reference hospitals in Ankara were retrospectively evaluated. Patients with FMF and concomitant sacroiliitis were included to the study. All patients had magnetic resonance imaging evidence of sacroiliitis.

RESULTS

Among 650 FMF patients, 17 (11 females, 6 males; mean age, 13.32 ± 4.24 years) (2.6%) of them were found to have sacroiliitis. Familial Mediterranean fever diagnosis was done prior to sacroiliitis diagnosis in 11 patients (65%) and concurrently or afterward in 6 patients (35%). Ten patients had isolated sacroiliitis, and 7 had associated diseases (5 enthesitis-related arthritis, 1 psoriatic arthritis, and 1 ulcerative colitis). Arthritis (59%), arthralgia (77%), leg pain (71%), heel pain (41%), and enthesitis (29%) were common complaints. Sacroiliac tenderness was detected in 77%, and M694V mutation in almost 90% of the patients. All patients received colchicine therapy. Additionally, 14 of them were treated with nonsteroidal anti-inflammatory drugs, 10 were on sulfasalazine treatment, and 7 of them were on biological agents.

CONCLUSIONS

Sacroiliitis can be seen in patients with FMF during childhood, and M694V mutation seems to be a susceptibility factor for its development. Inflammatory low-back pain and leg and heel pain could suggest sacroiliitis.

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.

Symptomatic patients with P369S-R408Q mutations: familial Mediterranean fever or mixed auto-inflammatory syndrome?

A 51-year-old South African female of Ashkenazi Jewish descent was admitted with acute pleuritic chest pain, shortness of breath, fatigue and fever. She experienced vague abdominal and calf pains for 30 years. Her monozygotic twin was investigated independently for recurrent abdominal pain. Despite initially responding to antibiotics, treating suspected pneumonia, she developed recurrent fevers and pleuritic chest pain. After thorough investigation without significant findings, she re-attended days after discharge with similar symptoms. Familial Mediterranean fever (FMF) was suggested as she met diagnostic criteria and responded to colchicine, though FMF normally presents before 20 years old. Genetic testing showed no pathogenic mutations but heterozygous P369S and R408Q mutations. The significance of these mutations remains unclear, as they are found in asymptomatic patients, suggesting incomplete penetrance. She remains well, with full symptom resolution, but mixed auto-inflammatory syndrome may be a more appropriate diagnosis in symptomatic patients with both P369S and R408Q mutations.

Clinical features and disease severity of Turkish FMF children carrying E148Q mutation

Background

Familial Mediterranean fever (FMF) is the most common hereditary monogenic autoinflammatory disease caused by mutations in the MEFV gene. It is controversial whether E148Q alteration is an insignificant variant or a disease‐causing mutation. The aim of this study was to evaluate the clinical features and disease severity of FMF patients carrying E148Q mutation.

Methods

Files of FMF patients were retrospectively evaluated. Patients with at least one E148Q mutation were included to the study. The clinical characteristics and disease severity of the patients who were carrying only E148Q mutation were compared with the patients who were compound heterozygous for E148Q and homozygous for M694V mutation.

Results

The study group comprised 33 patients who were homozygous or heterozygous for E148Q; 34 with compound heterozygous E148Q mutations and 86 patients who had homozygous M694V mutation. Patients who had only E148Q mutation were found to have the oldest mean age of disease onset and lowest mean disease severity score. Attack frequency and colchicine doses were lower in patients with only E148Q mutation as compared with the other two groups. The frequency of clinical findings such as fever, abdominal pain, arthralgia, and arthritis among the three groups was similar.

Conclusion

Familial Mediterranean fever patients with only E148Q mutation are presenting with late‐onset and milder disease course despite having similar clinical findings as compared with patients who had other mutations. Finally, we imply that E148Q is a mutation and colchicine treatment should be given.

Neonatal onset familial Mediterranean fever

Objectives: Familial Mediterranean fever (FMF) is an autosomal recessive disease characterised by recurrent, self-limited attacks of fever with serositis. Recently, it was shown that FMF patients with early disease onset have more severe disease. The aim of this study was to describe the demographic, clinical and genetic features of FMF patients who had disease onset during the neonatal period. Methods: Medical records of all patients diagnosed as FMF and had been seen in the outpatient clinic of Paediatric Rheumatology department between January 2013 and January 2014 were retrospectively evaluated. Patients with disease onset during the first month of life were included to the study. Results: Among 317 patients; 19 (12 males) were included to the study. Approximately 60% of the patients had family history of FMF. Homozygous p.M694V mutation was detected in 42% of the cases. Thirteen patients present with attacks of fever and remaining had attacks in the form of restlessness, resembling infantile colic starting in the neonatal period. Majority of these patients developed classical abdominal attacks between the ages of 1 and 2.5 years. The diagnosis of FMF was significantly delayed; the median age at onset of therapy was 3.5 years (range 7 months-17 years). Conclusion: Patients with FMF could have complaints even in the neonatal period. Homozygous p.M694V mutation is a prominent mutation in this group of patients. In order to prevent diagnostic delay physicians dealing with these type of patients should be more vigilant.

A Case of Familial Mediterranean Fever with Extensive Lymphadenopathy and Complex Heterozygous Genotype Presenting in the Fourth Decade

Familial Mediterranean fever (FMF) is an inherited disease caused by loss of function mutations in the MEFV gene encoding pyrin, a negative regulator of interleukin-1. The disease is characterized by recurrent fever and self-limited attacks of joint, chest, and abdominal pain but lymphadenopathy is an infrequent manifestation. While mesenteric lymphadenopathy has been described in several cases in the literature; hilar, paratracheal, axillary, pelvic, and retroperitoneal lymphadenopathy are extremely rare and have been reported separately in very few individuals. In this report, we present a patient with late-onset FMF with extensive lymphadenopathy in all of the aforementioned anatomic regions. Genetic analysis identified three heterozygous pyrin mutations in a patient with no affected family members. Genetic investigation of the patient's mother identified a novel carrier haplotype E148Q/P369S. The proband also inherited the previously described and rare A744S mutation previously not thought to be a disease-defining lesion. This unique compound heterozygous genotype resulted in a novel genotype-phenotype association producing an atypical clinical presentation of FMF that fits within the pattern of several case reports of late-onset disease with respect to clinical course and therapeutic response.

Inflammasome biology, molecular pathology and therapeutic implications

Inflammasomes are intracellular multiprotein signaling complexes, mainly present in myeloid cells. They commonly assemble around a cytoplasmic receptor of the nucleotide-binding leucine-rich repeat containing receptor (NLR) family, although other cytoplasmic receptors like pyrin have been shown to form inflammasomes. The nucleation of the multiprotein scaffolding platform occurs upon detection of a microbial, a danger or a homeostasis pattern by the receptor that will, most commonly, associate with the adaptor protein ASC (apoptosis-associated speck-like protein containing a CARD) through homotypic domain interactions resulting in recruitment of procaspase-1. This will lead to the autoproteolytic activation of caspase-1, which regulates the secretion of proinflammatory IL1β and IL18 cytokines and pyroptosis, a caspase-1-mediated form of cell death. Pyroptosis occurs through cleavage of Gasdermin D, a membrane pore forming protein. Recently, non-canonical inflammasomes have been described, which directly sense intracellular pathogens through caspase-4 and -5 in humans, leading to pyroptosis. Inflammasomes are important in host defense; however, a deregulated activity is associated with a number of inflammatory, immune and metabolic disorders. Furthermore, mutations in inflammasome receptor coding genes are causal for an increasing number of rare autoinflammatory diseases. Biotherapies targeting the products of inflammasome activation as well as molecules that directly or indirectly inhibit inflammasome nucleation and activation are promising therapeutic areas. This review discusses recent advances in inflammasome biology, the molecular pathology of several inflammasomes, and current therapeutic approaches in autoinflammatory diseases and in selected common multifactorial inflammasome-mediated disorders.

Long-term follow-up of paediatric MEFV carriers

Although familial Mediterranean fever (FMF) is inherited autosomal recessively, some heterozygotes may express disease phenotype and require therapy. To date, there is no study in the literature about how to follow-up Mediterranean fever (MEFV) heterozygotes who do not fulfil FMF criteria in the paediatric age group. This study aims to share a single-centre experience of the long-term clinical and laboratory follow-up of paediatric MEFV carriers. We reviewed the charts of 69 children who were heterozygous for MEFV variants. All children were followed-up with their routine analysis and serum amyloid A levels every 6 months. Thirty-nine children had pathogenic mutations and 30 children had variants of unknown significance. The mean follow-up was 3.2 ± 1.6 years (min 2 years, max 6 years). The children with pathogenic mutations had significantly higher mean SAA levels than the children with variants of unknown significance (p = 0.018); however, the mean CRP and ESR were similar. Besides, the children with pathogenic mutations complained of fever episodes significantly more than the children with variants of unknown significance (p = 0.04). None of the children had persistent proteinuria in the follow-up. We started colchicine in only two patients who were M694V heterozygous. Both patients had family history for FMF and fulfilled the disease criteria after 2 years of follow-up. Neither of these patients had persistently elevated acute phase reactants in their routine follow-up. This study suggested that routine clinical follow-up is useful; however, routine periodic laboratory workup is not necessary among MEFV carriers.

Comprehensive analysis of mutations in the MEFV gene reveal that the location and not the substitution type determines symptom severity in FMF

Background

Familial Mediterranean Fever (FMF) is an autoinflammatory disorder caused by mutations in the MEFV gene. These mutations appear in different populations with different frequencies and their caused symptom severities vary from mild to moderate to severe depending on the mutation type.

Methods

In this study, we analyzed the mutations that have been reported in the MEFV gene from symptomatic FMF patients and compared their frequencies in different populations from the 1000 Genome and the Exome databases, using statistical clustering. We also analyzed the nucleotide and amino acid substitution patterns across the MEFV gene.

Results

We found 16 (8%) nonsynonymous mutations outside exon 10 that did not cluster with known disease‐causing mutations (DCMs), due to their high frequencies in other populations. We also studied the substitution patterns for nucleotides and amino acids to determine the conserved and variable regions in the MEFV gene. In general more nonsynonymous substitutions were reported in exons 2, 3, and 10 from the FMF database (symptomatic FMF patients) compared to the 1000 Genome and the Exome databases. The same was true for amino acid (AA) substitutions where there were 1.5 times more radical (RAD) to conservative (CON) changes. However, when it came to AA substitutions exon 10 was quite conserved with a RAD/CON ratio of 0.9. In fact, we report that the most severe FMF symptoms are caused by conservative mutations in two highly conserved exon 10 regions.

Conclusion

We found presumptive FMF‐causing mutations that did not cluster with DCMs based on their allele frequencies. We also observed that the type of mutation is less likely to determine the severity of the FMF symptoms; rather it was the location of the mutations that was the determining factor.

MEFV mutations and their relation to major clinical symptoms of Familial Mediterranean Fever

Familial Mediterranean fever is a common hereditary disease in Turkey. To date, different mutational spectrum of MEFV gene was observed in studies carried out in different regions of Turkey but in most of these studies association of clinical symptoms of FMF to mutant genotypes have not been investigated in details. Here we report the MEFV gene variations in exons 2, 3, 5 and 10 and their relations to major clinical symptoms of FMF in 514 unrelated (245 males and 269 females) Turkish patients. MEFV mutations were found in 45% (n=230) of patients and 55% (n=284) of patients did not have any mutations. One hundred and thirty-seven (60%) patients were heterozygous, 57 (24.7%) patients were compound heterozygous, 33 (14%) patients were homozygous and 3 (1.3%) patients were having a complex genotype. Allele frequencies of MEFV mutations were M694V (48%), E148Q (18%), M680I (15%), V726A (12.5%), P369S (3.3%), R761H (0.9), K695R (0.9), E148V (0.9) and A744S (0.5%). Abdominal pain (76%) and fever (58%) were two most seen complications among patients followed by arthritis (28%) and chest pain (19%). Almost all major clinical symptoms of FMF were higher in patients with one or more M694V or M680I mutant allele. In contrast, patients having E148Q or V726A mutant allele showed fewer clinical FMF symptoms. Patients with P369S have higher abdominal pain, chest pain and fever than expected. Arthritis was high in K695R heterozygous genotype. One hundred and eighteen patients were carrying more than one polymorphic allele. The most common polymorphism was R202Q (13%). In addition, a novel heterozygous polymorphism at 564th nucleotide (C>T) of exon2 were found in 2 patients.

Familial Mediterranean fever-associated diseases in children

BACKGROUND

MEditerranean FeVer (MEFV) gene encodes for the pyrin protein and a mutated pyrin is associated with a prolonged or augmented inflammation. Hence, various diseases were reported to be associated with familial Mediterranean fever (FMF) or carriers of MEFV mutations. However, systematic evaluation of all associated diseases in children with FMF has not been done previously.

AIM

The aim of this study was to investigate the frequency and type of FMF-associated diseases in children.

DESIGN AND METHODS

Files of FMF patients who had been seen in two reference hospitals in Ankara, in the last two years, were retrospectively evaluated. Patients with FMF and concomitant diseases were included to the study.

RESULTS

Among 600 FMF patients, 77 were found to have a concomitant disease (12.8%). Thirty patients (5%) had vasculitis; 21 (3.5%) had juvenile idiopathic artritis (JIA); 7 (1.16%) had inflammatory bowel disease (IBD) and 19 had other diseases including 5 patients with isolated sacroiliitis. Overall, 13 (2.17%) patients had sacroiliitis in our cohort. The most frequent mutation was M694V/M694V (44%) and 81% of the patients had at least one M694V mutation. Majority of the patients (74%) developed associated diseases while they were not receiving colchicine therapy.

CONCLUSIONS

Certain inflammatory diseases including vasculitis, chronic arthritis and IBD were more frequently detected in patients with FMF during childhood. M694V mutation is a susceptibility factor for associated diseases. In countries where FMF is prevalent, clinicians dealing with FMF and other inflammatory diseases should be aware of these associations.

Genetic Analysis of Southwestern Iranian Patients with Familial Mediterranean Fever

BACKGROUND

Familial Mediterranean fever (FMF) is an autosomal recessive genetic disorder characterized by recurrent episodes of self-limited fever and serosal tissues inflammation.

METHODS

To evaluate clinical symptoms and common genetic mutations in southwestern Iranian patients with FMF, 20 unrelated patients were enrolled in this study based on clinical criteria. A panel of 12 common MEFV gene mutations was tested.

RESULTS

The most frequent clinical presentations of the patients were fever, colicky abdominal pain and arthritis. Eighteen patients responded completely to colchicine therapy. MEFV gene mutations were detected in only 40% of the patients. The most common mutation was E148Q, detected in five patients (25%). The V726A, M694V and P369S mutations were each observed in one patient.

CONCLUSIONS

Although none of the 12 mutations we included in our test panel was detected in 60% of our patients, all of them had FMF symptoms and responded well to colchicine. MEFV full gene sequencing analysis in these patients may lead to finding new mutations in southwestern Iranian FMF patients which would be helpful in designing a local diagnostic kit.

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.

Comprehensive genetic testing for primary immunodeficiency disorders in a tertiary hospital: 10-year experience in Auckland, New Zealand

Background and purpose

New Zealand is a developed geographically isolated country in the South Pacific with a population of 4.4 million. Genetic diagnosis is the standard of care for most patients with primary immunodeficiency disorders (PIDs).

Methods

Since 2005, we have offered a comprehensive genetic testing service for PIDs and other immune-related disorders with a published sequence. Here we present results for this program, over the first decade, between 2005 and 2014.

Results

We undertook testing in 228 index cases and 32 carriers during this time. The three most common test requests were for X-linked lymphoproliferative (XLP), tumour necrosis factor receptor associated periodic syndrome (TRAPS) and haemophagocytic lymphohistiocytosis (HLH). Of the 32 suspected XLP cases, positive diagnoses were established in only 2 patients. In contrast, genetic defects in 8 of 11 patients with suspected X-linked agammaglobulinemia (XLA) were confirmed. Most XLA patients were initially identified from absence of B cells. Overall, positive diagnoses were made in about 23% of all tests requested. The diagnostic rate was lowest for several conditions with locus heterogeneity.

Conclusions

Thorough clinical characterisation of patients can assist in prioritising which genes should be tested. The clinician-driven customised comprehensive genetic service has worked effectively for New Zealand. Next generation sequencing will play an increasing role in disorders with locus heterogeneity.

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

AIM

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

METHODS

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

RESULTS

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

CONCLUSION

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

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

BACKGROUND

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

The Pathogenesis of Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Cervical Adenitis Syndrome: A Review of Current Research

Background. PFAPA syndrome is a chronic disease that is characterized by recurrent episodes of high fever, aphthous stomatitis, pharyngitis, and cervical adenitis. Knowledge regarding the etiology of PFAPA is limited. Objectives. To provide up-to-date information considering etiology of PFAPA syndrome, by summarizing what has been explored and established in this area so far. Materials and Methods. PubMed, Web of Science, and Scopus databases were searched for pertinent reports. Eventually 19 articles were selected. The results were classified into categories regarding three areas of interest: familial occurrence, genetic basis, and immunological mechanisms of PFAPA. Results. Recent findings suggest that there is a familial tendency to PFAPA but the level of evidence does not warrant definite conclusions. The absence of a clear monogenic trait indicates a heterogenous, polygenic, or complex inheritance of PFAPA syndrome. As two mutations with a possible functional effect on the inflammasomes (MEFV E148Q and NLRP3 Q703K) have been found in several PFAPA cohorts, the role of inflammasome-related genes in PFAPA pathogenesis cannot be excluded. Immunological mechanisms of PFAPA involve an abnormal, IL-1β dependent innate immune response to an environmental trigger, which leads to Th1-driven inflammation expressed by recruitment of T-cells to the periphery.

High diagnostic yield of clinical exome sequencing in Middle Eastern patients with Mendelian disorders

Clinical exome sequencing (CES) has become an increasingly popular diagnostic tool in patients with heterogeneous genetic disorders, especially in those with neurocognitive phenotypes. Utility of CES in consanguineous populations has not yet been determined on a large scale. A clinical cohort of 149 probands from Qatar with suspected Mendelian, mainly neurocognitive phenotypes, underwent CES from July 2012 to June 2014. Intellectual disability and global developmental delay were the most common clinical presentations but our cohort displayed other phenotypes, such as epilepsy, dysmorphism, microcephaly and other structural brain anomalies and autism. A pathogenic or likely pathogenic mutation, including pathogenic CNVs, was identified in 89 probands for a diagnostic yield of 60%. Consanguinity and positive family history predicted a higher diagnostic yield. In 5% (7/149) of cases, CES implicated novel candidate disease genes (MANF, GJA9, GLG1, COL15A1, SLC35F5, MAGE4, NEUROG1). CES uncovered two coexisting genetic disorders in 4% (6/149) and actionable incidental findings in 2% (3/149) of cases. Average time to diagnosis was reduced from 27 to 5 months. CES, which already has the highest diagnostic yield among all available diagnostic tools in the setting of Mendelian disorders, appears to be particularly helpful diagnostically in the highly consanguineous Middle Eastern population.

Clinical features and genetic background of the periodic Fever syndrome with aphthous stomatitis, pharyngitis, and adenitis: a single center longitudinal study of 81 patients

PFAPA syndrome is the most common autoinflammatory disorder in childhood with unknown etiology. The aim of our study was clinical evaluation of PFAPA patients from a single tertiary care center and to determine whether variations of AIM2, MEFV, NLRP3, and MVK genes are involved in PFAPA pathogenesis. Clinical and laboratory data of consecutive patients with PFAPA syndrome followed up at the University Children's Hospital, Ljubljana, were collected from 2008 to 2014. All four genes were PCR amplified and directly sequenced. Eighty-one patients fulfilled criteria for PFAPA syndrome, 50 (63%) boys and 31 (37%) girls, with mean age at disease onset of 2.1 ± 1.5 years. Adenitis, pharyngitis, and aphthae were present in 94%, 98%, and 56%, respectively. Family history of recurrent fevers in childhood was positive in 78%. Nineteen variants were found in 17/62 (27%) patients, 4 different variants in NLRP3 gene in 13 patients, and 6 different variants in MEFV gene in 5 patients, and 2 patients had 2 different variants. No variants of clinical significance were found in MVK and AIM2 genes. Our data suggest that PFAPA could be the result of multiple low-penetrant variants in different genes in combination with epigenetic and environmental factors leading to uniform clinical picture.

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.

The coincidence of familial mediterranean Fever and hypereosinophilia in a patient with hereditary elliptocytosis

Familial Mediterranean fever (FMF) is a genetic disease with autosomal inheritance characterized by recurrent fever, abdominal pain, and serositis attacks. It is relatively common in the races and ethnical groups around Mediterranean Sea (Sephardic Jews, Armenians, Turks and Arabians). Hereditary elliptocytosis (HE) is common genetic defect of the red blood cell membrane skeleton. Spectrin mutations are the predominant causes of HE. Hypereosinophilia is defined as a number of eosinophil granulocytes equal or greater than 0.5 × 10(9)/L of circulating blood. The main causes are allergies and parasitic infections. This case report describes a Turkish female HE patient who presented with FMF and hypereosinophilia. Genetic analysis revealed heterozygous mutation in exon 10 of the MEFV gene (V726A). The patient was successfully treated with colchicine and steroid treatment at 3-month follow-up. To the best of our knowledge, this is the first report of association between FMF, HE, and hypereosinophilia.

Common MEFV gene mutations in Turkish patients with Behcet's disease

Behcet's disease (BD) is a chronic systemic inflammatory disorder whose etiology has not been fully established yet. The MEditerranean FeVer (MEFV) gene has been identified as the cause of Familial Mediterranean Fever (FMF). BD shows similarities with FMF, in terms of clinical findings and treatments, as well as their geographical and ethnic co-occurrence. In this study we investigated common MEFV gene mutation frequencies in Turkish patients with BD in an area of Turkey where both diseases are frequently encountered. We screened 207 BD patients who had no symptoms and family history for FMF and 200 healthy subjects for five common MEFV gene mutations (E148Q, M680I, M694V, V726A, P369S) and clinical features. Seventy-five patients were found to carry a single MEFV mutation, and six patients were compound heterozygous. The difference in the frequency of the MEFV mutation between the BD and control groups was statistically significant (p<0.001, odds ratio [OR] 2.74, 95% confidence interval [CI] 1.75-4.29). The frequencies of E148Q and M680I mutations were significantly higher in the BD group (p=0.001, p=0.046, respectively). The frequency of uveitis was significantly lower in patients with the mutation than in patients without the mutation (p=0.029, OR 0.54, 95% CI 0.30-0.98). There was no statistical significance between carriers and non-carriers with respect to gender and other manifestations of BD. The frequency of the MEFV mutation was significantly higher in patients with BD compared to the healthy control group. Based on our results, MEFV mutations appear to have a role in the pathogenesis of BD.