The clinical and genetical features of 124 children with Familial Mediterranean fever: experience of a single tertiary center

Not easy-peasy to diagnose: familial Mediterranean fever unaccompanied by fever

Classical attacks of familial Mediterranean fever (FMF) are often accompanied by fever, but some of the patients have attacks without fever. This study aimed to compare the characteristics of FMF patients with and without fever during their attacks and draw attention to the different clinical presentations of FMF in children. Medical files of patients aged 0-18 years who were followed up with the diagnosis of FMF in two reference pediatric rheumatology centers were reviewed retrospectively. The patients were divided into two groups: children who had had no fever in any of their attacks were assigned as group 1, and those who had fever during their attacks were classified as group 2. Out of 2003 patients evaluated, 191 (9.53%) patients had attacks not accompanied by fever and their median age at onset of symptoms (7.0 vs. 4.0 years, p < 0.001) and the median age at diagnosis (8.6 vs. 6.0 years, p < 0.001) were significantly higher; however, group 2 had a delay in diagnosis. The annual number of attacks and abdominal attacks were more common in group 2; arthritis, arthralgia, erysipelas-like rash, exercise-induced leg pain, and myalgia were more common in group 1.    Conclusion: The data from the assessment of children with FMF attacks not accompanied with fever were presented for the first time. Children with late age onset of FMF and dominance of musculoskeletal features may display attacks not accompanied with fever. What is Known: • Familial Mediterranean fever (FMF) is the most common inherited auto-inflammatory disease, characterized by recurrent attacks of fever, serositis, and musculoskeletal symptoms. • Although fever is the most common symptom, few studies have reported attacks without fever. What is New: • The aim of this study was to identify patients with FMF but without fever during attacks and to demonstrate their distinctive presentations. • We found that 7% of our patients had afebrile attacks with predominant musculoskeletal symptoms and were diagnosed earlier than patients with febrile attacks, probably due to early referral to pediatric rheumatology clinics.

Toll-like receptor-4 gene variations in Egyptian children with familial Mediterranean fever

Background

Familial Mediterranean fever (FMF) is an autosomal recessive disorder affecting people in the region of the Mediterranean Sea. It is usually associated with mutation in Mediterranean fever (MEFV) gene that encodes the pyrin protein, which affects the innate inflammatory response. Toll-like receptors (TLR) are a family of pattern recognition receptors that recognize pathogenic microbes and activate antimicrobial defense mechanisms. Toll-like receptor 4 (TLR-4) is concerned with recognition of gram-negative organisms. There is growing clinical evidence suggesting a role for expression of TLRs in the immune pathogenesis of FMF. Thus, the aim of the current study was to evaluate the presence of TLR-4 (p.Asp299Gly) and TLR-4 (p.Thr399Ile) gene variants in association with Egyptian children having FMF, furthermore, its effect on disease course and severity.

Results

Seventy Egyptian children diagnosed as having FMF, together with 50 age and gender-matched controls were enrolled in the study. The TLR-4 (p.Asp299Gly) and (Thr399Ile) gene variants were determined by PCR-RFLP analysis for all studied patients and controls. TLR-4 p.Asp299Gly gene variant was detected in 1 (1.4%) of the patients and p.Thr399Ile gene variant was detected in 2 (2%). None of the controls had any of the two tested gene variants. All found variations were heterozygous. We could not find a statistically significant association with disease severity in cases with or without TLR-4 gene variants (P = 0.568). Patients with M694V gene mutation showed a higher disease severity (P = 0.035).

Conclusion

TLR-4 (p.Asp299Gly) and (p.Thr399Ile) gene variants were not found to have a link with the occurrence, the clinical picture of FMF, its severity, and response to colchicine treatment in Egyptian children. M694V gene mutation seems to be associated with higher disease severity. Further larger studies are needed to verify these results.

Twenty-Year Experience of a Single Referral Center on Pediatric Familial Mediterranean Fever: What Has Changed Over the Last Decade?

BACKGROUND/OBJECTIVE

Familial Mediterranean fever (FMF) is the most common autoinflammatory disease and is characterized by recurrent fever and serositis episodes. We aimed to share our 20-year FMF experience, clarify a phenotype-genotype correlation, and compare the characteristics and outcomes of pediatric FMF patients over the last 2 decades in this study.

METHODS

This medical record review study included 714 pediatric FMF patients (340 females, 374 males), diagnosed by Tel Hashomer diagnostic criteria between January 2009 and January 2019 and followed up in our department. Demographic and disease characteristics, obtained from medical records of the patients, were compared between patients with M694V homozygosity and other genotypes and showed whether they were diagnosed before (n = 137) or after January 2010 (n = 577). χ2, Student t, and Mann-Whitney U tests were used to compare categorical and continuous variables between these groups.

RESULTS

The most common symptoms were abdominal pain (92%), fever (89.5%), and arthralgia (64.5%). Mean ages at symptom onset and diagnosis were 5.16 ± 3.73 and 7.71 ± 3.87 years, respectively. M694V homozygosity was recorded in 111 patients (15.5%). Fever, arthralgia, arthritis, myalgia, erysipela-like erythema, colchicine resistance, and subclinical inflammation were more frequent, and mean disease severity score was higher in patients with M694V homozygosity. Fever, chest pain, and proteinuria were statistically more frequent in patients diagnosed before January 2010. Although M694V homozygosity rate was similar, patients diagnosed in the last decade had lower mean disease severity score.

CONCLUSIONS

With this study, we speculate that although genotype and delay in diagnosis were similar, patients diagnosed in the last decade have a milder disease severity.

Lack of clear and univocal genotype-phenotype correlation in familial Mediterranean fever patients: A systematic review

Familial Mediterranean fever (FMF) is the most common autosomal recessive autoinflammatory disease. To date, following the isolation of more than 280 MEFV sequence variants, the genotype-phenotype correlation in FMF patients has been intensively investigated; however, an univocal and clear consensus has not been yet reached. Thus, the aim of this systematic review was to analyze the available literature findings in order to provide to scientific community an indirect estimation of the impact of genetic factors on the phenotypic variability of FMF. This systematic review has been conducted according to the Preferred Reporting Items for Systematic reviews and Meta-Analysis (PRISMA) guidelines. The p.M694V mutation was reported to have a relatively severe clinical course, similarly, patients homozygous for M694I and M680I, or carrying a combination of both at codons 694 and 680, have a severe disease. Also, patients homozygous for M694V and V726A variants experienced more severe clinical picture. Conversely, heterozygous p.V726A and p.E148Q genotypes have been correlated with a milder disease course. At present, doubts remain on the potential pathogenic role of E148Q variant. The heterogenity in clinical FMF manifestations reflects the changes occuring in repertoire of mutations. We believe that clinical criteria and gene tests, enhancing each other, could better support the diagnosis of FMF.

The Influence of Concomitant Disorders on Disease Severity of Familial Mediterranean Fever in Children

Objectives

This study aims to describe the effects of concomitant disorders on the course of familial Mediterranean fever (FMF) and the relevance of genotype on these associations.

Patients and methods

Files of 494 FMF patients (257 males, 237 females; mean age 12.8±1.94 years; range 1.6 to 23 years) were retrospectively examined. Age of diagnosis, sex, MEditerrenean FeVer mutations, colchicine dosage, disease severity score and concomitant diseases in FMF course were recorded. FMF diagnoses were based on Tel-Hashomer criteria and disease severity was determined by international severity scoring system for FMF. Patients were divided into two groups as M694V positives and M694V negatives. We compared the groups in terms of accompanying illnesses, MEditerrenean FeVer mutations, and disease severity scores among five concomitant diseases: juvenile idiopathic arthritis (JIA), asthma, Henoch- Schonlein purpura, periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome, and others.

Results

The mean age at diagnosis was 8.7±1.9 years. Eighty-five patients (17.2%) had accompanying diseases including JIA, asthma, periodic fever, aphthous stomatitis, pharyngitis and adenitis syndrome, and Henoch-Schonlein purpura. Mean disease severity scores were 2.4±1.1 in patients with only FMF and 3.0±1.5 in patients with concomitant disorders (p=0.001). Patients with concomitant JIA showed the highest severity scores (4.3±1.6). A statistically significant difference was found with one-way analysis of variance.

Conclusion

Our findings indicate that concomitant diseases, particularly JIA, influence FMF severity. Therefore, it may be beneficial to focus on diagnosis and treatment of comorbid inflammatory diseases, which may worsen the course of FMF.

Association between sequence variations of the Mediterranean fever gene and the risk of migraine: a case-control study

Migraine pathogenesis involves a complex interaction between hormones, neurotransmitters, and inflammatory pathways, which also influence the migraine phenotype. The Mediterranean fever gene (MEFV) encodes the pyrin protein. The major role of pyrin appears to be in the regulation of inflammation activity and the processing of the cytokine pro-interleukin-1β, and this cytokine plays a part in migraine pathogenesis. This study included 220 migraine patients and 228 healthy controls. Eight common missense mutations of the MEFV gene, known as M694V, M694I, M680I, V726A, R761H, K695R, P369S, and E148Q, were genotyped using real-time polymerase chain reaction with 5' nuclease assays, which include sequence specific primers, and probes with a reporter dye. When mutations were evaluated separately among the patient and control groups, only the heterozygote E148Q carrier was found to be significantly higher in the control group than in the patient group (P=0.029, odds ratio [95% confidence interval] =0.45 [0.21-0.94]). In addition, the frequency of the homozygote and the compound heterozygote genotype carrier was found to be significantly higher in patients (n=8, 3.6%) than in the control group (n=1, 0.4%) (P=0.016, odds ratio [95% confidence interval] =8.57 [1.06-69.07]). However, there was no statistically significant difference in the allele frequencies of MEFV mutations between the patients and the healthy control group (P=0.964). In conclusion, the results of the present study suggest that biallelic mutations in the MEFV gene could be associated with a risk of migraine in the Turkish population. Moreover, MEFV mutations could be related to increased frequency and short durations of migraine attacks (P=0.043 and P=0.021, respectively). Future studies in larger groups and expression analysis of MEFV are required to clarify the role of the MEFV gene in migraine susceptibility.

Relationship between periodontal destruction and gene mutations in patients with familial Mediterranean fever

Recent studies have shown that genetic factors involved in the host responses might determine the disease severity for both familial Mediterranean fever (FMF) and periodontitis. The present study aimed to investigate the relationship of FMF with periodontitis and to search for the potential association between periodontitis and MEFV gene missense variations in patients with FMF. The study consisted of 97 FMF patients and 34 healthy volunteers. FMF patients were classified according to the kind of MEFV gene mutation: (1) patients with homozygous M694V gene mutation, (2) patients with heterozygous M694V gene mutation, and (3) patients with MEFV gene different mutations. Gingival Index (GI), Plaque Index (PI), probing pocket depth (PD), and clinical attachment level (CAL) were measured in all participants. The results of multivariate logistic regression showed a highly significant association between homozygous M694V gene mutation and periodontitis in FMF patients (p < 0.05). After adjusting for potential confounders (smoking, body weight, age, and gender), FMF patients with homozygous M694V gene mutation were 3.51 (1.08-11.45) times more likely to present periodontitis than the other FMF patients. These results indicate that the presence of homozygous M694V gene mutation seems to increase the risk for periodontitis in FMF patients.

Mean Platelet Volume and Splenomegaly as Useful Markers of Subclinical Activity in Egyptian Children with Familial Mediterranean Fever: A Cross-Sectional Study

Objective. To study whether mean platelet volume (MPV) and splenomegaly could be used as subclinical inflammatory markers in children with familial Mediterranean fever (FMF) at the attack-free period. Patients and Methods. The study included ninety-seven children with FMF. MPV was carried out within 4 hours of blood sampling according to standard laboratory practice. Splenomegaly was determined by abdominal ultrasound (USG). Results. High MPV was detected in 84.45% of our studied patients and was significantly higher in FMF patients with splenomegaly than in patients without splenomegaly. There was a statistically significant correlation between MPV and splenic span (P = 0.045). Conclusion. Elevated MPV and its significant correlation with splenic span in FMF children during the attack-free periods support the use of MPV and splenomegaly as useful markers of the subclinical inflammation in FMF patients at the attack-free period.

The frequency of Familial Mediterranean fever gene mutations and genotypes at Kirikkale and comparison with the mean of regional MEFV mutation frequency of Turkey

In this study we have retrospectively analysed the mutation spectrum of the 351 Familial Mediterranean fever patients referred to Kırıkkale University Faculty of Medicine, Department of Medical Genetics Laboratory over a period of 5 years and compared them with Turkey's mean. We have found 11 different mutations, including rare mutations such as F479L, K695R, M680I(G/A) and 45 different genotypes showing the heterogeneity of MEFV mutations in Central Anatolia. The most three prevalent mutations were M694V (14.8%), E148Q (7.1%) and M680I(G/C) (4.1%) in accordance with the literature. We have also investigated R202Q in our routine molecular diagnosis. Mutation causing R202Q (c.605G > A) change was described as a frequent polymorphism and G allele was found in linkage disequilibrium (LD) with M694V. There are limited number of studies investigating R202Q, some of them implicate that its homozygote state is disease causing. We showed the high frequency of R202Q (23.7%) with and without M694V in all the groups analysed and its high LD rate with M694V in the diagnosed group. Our study is reflecting the mutational heterogeneity of MEFV and summarize mutational spectrum of Turkey's geographical regions and overall Turkey.

A molecular analysis of familial Mediterranean fever disease in a cohort of Turkish patients

BACKGROUND AND OBJECTIVES

Familial Mediterranean fever (FMF) is an autosomal recessive disorder caused by mutations in MEFV gene, which encodes pyrin. FMF is especially prevalent among Turks, Armenians, non-Ashkenazi Jews, and Arabs. The aim of this study was to determine the frequency and spectrum of 12 MEFV mutations of these patients and any genotype-phenotype correlation in this large Turkish group.

DESIGN AND SETTING

A retrospective study at Erciyes University Medical Faculty, from January 2007 to June 2009.

PATIENTS AND METHODS

We enrolled 446 Turkish FMF patients and identified the known 12 MEFV mutations with clinical investigations. DNA was amplified by PCR and subjected to reverse hybridization for the detection of MEFV gene mutations.

RESULTS

Among the 446 patients, 103 (46.6%) had a heterozygous genotype, 44 (19.9%) had a homozygous genotype, and 74 (33.49%) had a compound heterozygous genotype. The most common mutation detected was heterozygote M694V (46/221). Of the included 446 patients, 218 (48.87%) were male and 228 (51.12%) were female. High parental consanguinity rates affect FMF development. The clinical spectrum varied with different mutation profiles.

CONCLUSIONS

This study plays an important role in detecting the distribution of MEFV mutations and determining clinical approaches among Turk FMF patients. Also, we seemed to detect a distinctive clinical picture, specifically a lower frequency of amyloidosis.

Chronic inflammation in FMF: markers, risk factors, outcomes and therapy

Familial Mediterranean fever (FMF) is the most common of the hereditary periodic fever syndromes. Although the typical clinical course of FMF is characterized by bouts of painful inflammation, this presentation represents only the tip of the iceberg. In many patients inflammation can persist in attack-free periods, as shown by high levels of acute-phase proteins, cytokines and inflammation-induced proteins. This subclinical inflammation puts patients at risk of developing complications such as anemia, splenomegaly, decreased bone mineral density, heart disease and life-threatening amyloid A amyloidosis, among others. In this article, we review the published data on markers and other factors involved in the persistence of inflammation in patients with FMF during attack-free periods, examine the risk factors for the development of this subclinical inflammation, summarize the complications of chronic inflammation in FMF and propose a new strategy for treatment, based on these data.

Fevers and the rheumatologist

Fevers in children are mainly due to infection, malignancy or inflammatory conditions. Rheumatologists have an important role in the care of inflammatory conditions, many of which are associated with fevers. Seven conditions, the hereditary recurrent fever syndromes, have been defined with the presenting symptom of recurring fever, and for which mutation of a single gene has been defined: Chronic infantile neurological articular syndrome (CINCA), Familial cold autoinflammatory syndrome (FACS), Familial Mediterranean fever (FMF), hyperimmunoglobulinemia D (HIDS), Muckle-Wells syndrome (MWS), Pyogenic sterile arthritis and Pyoderma gangrenosum (PAPA) and Tumour necrosis factor receptor-associated periodic syndrome (TRAPS) . These conditions will be discussed in detail in regard to how they fit into the wider picture of pediatric rheumatological conditions, how the diagnoses may be established and the current recommended treatments for each condition.

Prevalence of known mutations in the MEFV gene in a population screening with high rate of carriers

The Familial Mediterranean Fever (FMF) shows an autosomal recessive pattern of inheritance and affects certain ethnic groups. Disease is caused by mutations in MEFV gene and more than 180 mutations have been defined in affected individuals. Current study aimed to determine the frequency-type of the mutations for MEFV gene in Sivas-middle Anatolian city. The cohort was composed of 3340 patients. MEFV gene mutations were studied by multiplex PCR based reverse hybridization stripAssay method. Patients' clinical features were; family history: 68%, erysipelas-like erythema: 17.6%, fever: 89.9%, abdominal pain: 84.2%, peritonitis: 90.2%, arthritis: 33%, pleuritis: 14.2%, parental consanguinity: 21.2%. Current results revealed that M694V is the most frequent mutation (43.12%), followed by E148Q (20.18), M680I(G/C) (15.00%) and V726A (11.32%). The study population has a high rate of carriers and the E148Q mutation frequency was found to be highest when compared to the other regions of Turkey and other Mediterranean groups.

A case of familial Mediterranean fever associated with compound heterozygosity for the pyrin variant L110P-E148Q/M680I in Japan

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent and self-limited fever attacks and serositis/arthritis. The M694V, M694I, M680I, V726A, and E148Q mutations in MEFV, the gene responsible for FMF, account for most FMF cases in Mediterranean populations. In Japan, M694I and E148Q are most frequently detected; M694V, M680I, and V726A have not been identified so far. We report the first case of FMF associated with M680I in Japan.