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

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

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

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

Interrupting an IFN-γ-dependent feedback loop in the syndrome of pyogenic arthritis with pyoderma gangrenosum and acne.

OBJECTIVES: To study the molecular pathogenesis of PAPA (pyogenic arthritis, pyoderma gangrenosum and acne) syndrome, a debilitating hereditary autoinflammatory disease caused by dominant mutation in PSTPIP1. METHODS: Gene knock-out and knock-in mice were generated to develop an animal model. THP1 and retrovirally transduced U937 human myeloid leukaemia cell lines, peripheral blood mononuclear cells, small interfering RNA (siRNA) knock-down, site-directed mutagenesis, cytokine immunoassays, coimmunoprecipitation and immunoblotting were used to study inflammasome activation. Cytokine levels in the skin were evaluated by immunohistochemistry. Responsiveness to Janus kinase (JAK) inhibitors was evaluated ex vivo with peripheral blood mononuclear cells and in vivo in five treatment-refractory PAPA patients. RESULTS: The knock-in mouse model of PAPA did not recapitulate the human disease. In a human myeloid cell line model, PAPA-associated PSTPIP1 mutations activated the pyrin inflammasome, but not the NLRP3, NLRC4 or AIM2 inflammasomes. Pyrin inflammasome activation was independent of the canonical pathway of pyrin serine dephosphorylation and was blocked by the p.W232A PSTPIP1 mutation, which disrupts pyrin-PSTPIP1 interaction. IFN-γ priming of monocytes from PAPA patients led to IL-18 release in a pyrin-dependent manner. IFN-γ was abundant in the inflamed dermis of PAPA patients, but not patients with idiopathic pyoderma gangrenosum. Ex vivo JAK inhibitor treatment attenuated IFN-γ-mediated pyrin induction and IL-18 release. In 5/5 PAPA patients, the addition of JAK inhibitor therapy to IL-1 inhibition was associated with clinical improvement. CONCLUSION: PAPA-associated PSTPIP1 mutations trigger a pyrin-IL-18-IFN-γ positive feedback loop that drives PAPA disease activity and is a target for JAK inhibition.

Unraveling the genome: Familial Mediterranean fever.

ABSTRACT: Familial Mediterranean fever (FMF) is an inherited, autoinflammatory disease with a high prevalence in Middle Eastern and Mediterranean populations including Turks, Iranian, Spanish, Sephardic Jews, Arabs, and other Mediterranean ethnic groups. Autoinflammatory diseases are genetically predetermined disorders with multisystem effects primarily caused by defects in innate immunity. Although primarily known for an autosomal recessive mode of inheritance, there are increasing case reports associated with single Mediterranean fever (MEFV) mutation or dominant transmission. There have been over 300 variants identified in the MEFV gene; however, roughly 9-11 variants are responsible for the phenotypical expression seen with FMF. Symptoms include recurrent episodes of fever of unknown origin, abdominal, chest, or joint pain because of serosal inflammation. Persistent elevations in serum amyloid A can lead to complications like renal amyloidosis, kidney dysfunction, and end-stage kidney disease. Familial Mediterranean fever is diagnosed clinically using the Tel-Hashomer criteria and confirmed through genetic testing. Treatment includes initiation of colchicine with the goal of stopping attacks and preventing renal dysfunction and end-stage kidney disease. Genetic testing helps to identify the specific mutation allowing the provider to create a patient-specific treatment plan, monitor for complications such as renal amyloidosis, and enhance knowledge on the genetic heterogeneity and possible epigenetic factors.

Fiebre Mediterránea familiar: un diagnóstico a tener en mente / Familial Mediterranean fever: a diagnosis to keep in mind

Familial Mediterranean Fever is a hereditary inflammatory disease of predominantly autosomal recessive inheritance, produced by mutations in the MEFV gene that is found on the short arm of chromosome 16, characterized by recurrent episodes of fever accompanied by peritonitis, pleuritis, arthritis or erysipelaslike erythema. An episode lasts from one to three days, and its frequency is very variable. This disease is more frequent among Mediterranean populations, Jews from North Africa (not Ashkenazi), Armenians, Turks and Arabs. However, in recent years more cases have been reported in countries not related to this area. There are no formal studies of epidemiology in Chile. We present the case of one patient of Egyptian/ Jewish ancestry, and the case of a family of German/Spanish ancestry, all Chileans with semiology and characteristic evolution of familial Mediterranean fever and heterozygous positive molecular study. The absence of diagnosis in non-Mediterranean countries may be due to the lack of awareness of this disease. In Chile there has been a rise in cases given by migrants and their offspring, so it is very important to keep in mind as possible diagnosis in case of pain and fever of unknown origin. On the other hand, the familial Mediterranean fever is mainly of autosomal recessive inheritance, but dominant variants have been described. Both cases described in this work present the variant in which the disease manifests itself in its heterozygous form, generating an autosomal dominant inheritance, which would increase the number of affected individuals in the population.

La fiebre mediterránea familiar es un trastorno auto inflamatorio hereditario de herencia predominantemente autosómica recesiva, producida por mutaciones en el gen MEFV que se encuentra en el brazo corto del cromosoma 16, y que se caracteriza por episodios recurrentes de fiebre acompañada de peritonitis, pleuritis, artritis o eritema tipo erisipela. Un episodio dura entre uno y tres días, y su frecuencia es muy variable. Esta enfermedad es más frecuente entre las poblaciones mediterráneas, judíos del norte de África (no ashkenazíes), armenios, turcos y árabes. Sin embargo, en los últimos años se han reportado más casos en países no relacionados con esta área. No hay estudios epidemiológicos formales en Chile. Presentamos el caso de una paciente de ascendencia egipcia/judía, y el caso de una familia de ascendencia alemana/española, todos chilenos con semiología y evolución característica de fiebre mediterránea familiar y estudio molecular positivo heterocigoto. La falta de diagnóstico en países no mediterráneos puede deberse a la falta de conocimiento de esta enfermedad. En Chile han aumentado los casos dado el aumento de migrantes y sus descendientes, por lo que es importante tener este diagnóstico como posibilidad en caso de dolor y fiebre de origen desconocido. Por otro lado, la fiebre mediterránea familiar es principalmente de herencia autosómica recesiva, pero se han descrito variantes dominantes. Los dos casos descritos en este trabajo presentan la variante en la que la enfermedad se manifiesta en su forma heterocigota, generando una herencia autosómica dominante, lo que aumentaría el número de individuos afectados en la población.

Mutaciones en el gen MEFV y evolución clínica en pacientes pediátricos con púrpura de Schonlein-Henoch / MEFV gene mutations and clinical course in pediatric patients with Henoch-Schonlein purpura

Objetivo. Determinar la frecuencia de mutaciones del gen MEFV en niños con diagnóstico de púrpura de Schonlein-Henoch y evaluar el efecto que tienen en el pronóstico. Materiales y métodos. Estudio transversal que incluyeron pacientes pediátricos de entre 2 y 11 años, con diagnóstico de púrpura de Schonlein-Henoch. Se estudiaron para detectar 6 mutaciones en el gen MEFV (M694V, M680I, A744S, R202Q, K695R y E148Q). Resultados. Se incluyeron ochenta pacientes, de los cuales el 55% eran de sexo masculino (n= 44). La media de edad fue 6,44 ± 2,52 años. Durante el seguimiento, 9 pacientes presentaron recurrencia de la enfermedad, 5 sufrieron invaginación intestinal y 1 paciente tuvo convulsiones. Aproximadamente la mitad de los pacientes recibió corticoides. En 44 pacientes (55%) no se detectaron mutaciones en el gen MEFV. En 19 pacientes (22%) hubo una mutación heterocigota. Se encontró E148Q en 8 pacientes, M694V en 5 pacientes, A744S en 4 pacientes y la mutación heterocigota R202Q en 2 pacientes. En 1 paciente se detectó la mutación heterocigota M608I y en otro paciente se encontró la mutación homocigota M694V. En 15 pacientes se encontraron mutaciones heterocigotas compuestas en el gen MEFV. Las mutaciones en el gen MEFV no se correlacionaban con la frecuencia de compromiso renal y gastrointestinal ni con el pronóstico, desarrollo de complicaciones y uso de corticoides. Conclusiones. Las mutaciones en el gen MEFV no se correlacionan con la evolución clínica ni con las complicaciones en pacientes pediátricos con púrpura de Schonlein-Henoch en Turquía.

Objective. To determine the frequency of the MEFV gene mutations in pediatric patients diagnosed with HSP and to assess the effect of the MEFV gene mutations on their prognosis. Material and Methods. Ccross-sectional study; pediatric patients between 2-11 years diagnosed with HSP were included. These cases were investigated for 6 MEFV gene mutations (M694V, M680I, A744S, R202Q, K695R, E148Q). Results. Eighty cases were included in the study of which 55% were male (n= 44). The mean age was 6.44 ± 2.52 years. Disease recurrence occurred in 9 patients, invagination in 5 patients and convulsion in 1 patient during follow-up. Approximately half of the patients received steroids. The MEFV gene mutations was not detected in 44 (55%) of the patients. There was a heterozygous mutation in 19 (22%). E148Q was found in 8 patients, M694V in 5 patients, A744S in 4 patients, and the R202Q heterozygous mutation in 2 patients. The M608I homozygous mutation was detected in 1 patient and the M694V homozygous mutation in 1 patient. The compound heterozygous MEFV gene mutations was found in 15 patients. The presence of the MEFV gene mutations was not correlated with the frequency of renal and gastrointestinal involvement and prognosis, the development of complications and the use of steroids. Conclusion. The presence of the MEFV gene mutations does not correlate with the clinical course and complication in Turkish pediatric patients with HSP.

Diretrizes de conduta e tratamento de síndromes febris periódicas associadas a febre familiar do Mediterrâneo / Guidelines for the management and treatment of periodic fever syndromes familial Mediterranean fever

Resumo Objetivo: Estabelecer diretrizes baseadas em evidências científicas para manejo da febre familiar do Mediterrâneo (FFM). Descrição do método de coleta de evidência: A diretriz foi elaborada a partir de 5 questões clínicas que foram estruturadas por meio do PICO (Paciente, Intervenção ou Indicador, Comparação e Outcome), com busca nas principais bases primárias de informação científica. Após definir os estudos potenciais para sustento das recomendações, esses foram graduados pela força da evidência e pelo grau de recomendação. Resultados: Foram recuperados, e avaliados pelo título e resumo, 10.341 trabalhos e selecionados 46 artigos para sustentar as recomendações. Recomendações: 1. O diagnóstico da FFM é baseado nas manifestações clínicas, caracterizadas por episódios febris recorrentes associados a dor abdominal, torácica ou artrite de grandes articulações; 2. A FFM é uma doença genética que apresenta traço autossômico recessivo ocasionada por mutação no gene MEFV; 3. Exames laboratoriais são inespecíficos e demonstram níveis séricos elevados de proteínas inflamatórias na fase aguda da doença, mas também, com frequência, níveis elevados mesmo entre os ataques. Níveis séricos de SAA podem ser especialmente úteis no monitoramento da eficácia do tratamento; 4. A colchicina é a terapia de escolha e demonstrou eficácia na prevenção dos episódios inflamatórios agudos e progressão para amiloidose em adultos; 5. Com base na informação disponível, o uso de medicamentos biológicos parece ser opção para pacientes com FFM que não respondem ou que são intolerantes à terapia com colchicina.

Abstract Objective: To establish guidelines based on scientific evidence for the management of familial Mediterranean fever. Description of the evidence collection method: The Guideline was prepared from 5 clinical questions that were structured through PICO (Patient, Intervention or indicator, Comparison and Outcome), to search in key primary scientific information databases. After defining the potential studies to support the recommendations, these were graduated considering their strength of evidence and grade of recommendation. Results: 10,341 articles were retrieved and evaluated by title and abstract; from these, 46 articles were selected to support the recommendations. Recommendations: 1. The diagnosis of FMF is based on clinical manifestations, characterized by recurrent febrile episodes associated with abdominal pain, chest or arthritis of large joints; 2. FMF is a genetic disease presenting an autosomal recessive trait, caused by mutation in the MEFV gene; 3. Laboratory tests are not specific, demonstrating high serum levels of inflammatory proteins in the acute phase of the disease, but also often showing high levels even between attacks. SAA serum levels may be especially useful in monitoring the effectiveness of treatment; 4. The therapy of choice is colchicine; this drug has proven effectiveness in preventing acute inflammatory episodes and progression towards amyloidosis in adults; 5. Based on the available information, the use of biological drugs appears to be an alternative for patients with FMF who do not respond or are intolerant to therapy with colchicine.