Prevalence and significance of the MEFV gene mutations in childhood Henoch–Schönlein purpura without FMF symptoms

Clinical Associations of E148Q Heterozygosity: What to Expect From E148Q?

OBJECTIVE

The exact effects of MEFV variants on inflammation are still under investigation, and reports on variants of unknown significance, particularly the E148Q variant, have been conflicting. Therefore, this study aims to investigate patients exhibiting E148Q heterozygosity, focusing on diagnoses and disease courses to assist physicians in interpreting the variant.

METHODS

Data of pediatric patients presenting to the Pediatric Rheumatology clinic between November 2016 and September 2023, exhibiting only E148Q heterozygosity in MEFV gene analysis, were extracted. Patients who were lost before 9 months of follow-up have been excluded to ensure the completion of initial diagnostic tests and evaluations.

RESULTS

Among the 119 patients with E148Q variant, the diagnoses were as follows: healthy, 51.3%; IgA vasculitis, 10.1%; Familial Mediterranean Fever (FMF), 7.6%; Periodic fever, Aphtous stomatitis, Pharyngitis, Adenitis (PFAPA), 6.7%; and other diagnoses, 19.3%. IgA vasculitis patients experienced articular, gastrointestinal, and renal involvement at rates of 91.7%, 58.3%, and 16.7%, respectively. Complete response, partial response, and no response to colchicine were 37.5%, 12.5%, and 50%, respectively, in PFAPA patients. All FMF patients responded to colchicine treatment resulting in reduced mean FMF episode counts in 6 months from 3.22 ± 0.92 to 0.56 ± 0.52.

CONCLUSIONS

The E148Q variant may amplify inflammation and modify disease courses. Patients with the E148Q variant experiencing typical FMF episodes should receive colchicine, but clinicians should exercise caution regarding alternative diagnoses. Additionally, the E148Q variant may increase acute phase reactants and disease severity in IgA vasculitis. However, to reach definitive conclusions on its treatment-modifying role in PFAPA, universal diagnosis and treatment response criteria should be adopted.

IgA Vasculitis in Japanese Patients Harboring MEFV Mutations: A Case Report and Review of the Literature

Immunoglobulin A vasculitis (IgAV) is the most common vasculitis of childhood. However, its etiology remains unknown. In the Mediterranean region, 10% of patients with IgAV harbor homozygous and compound heterozygous mutations in the Mediterranean fever (MEFV) gene. Thus, such mutations may be involved in the development of IgAV. Herein, we present a five-year-old girl presented with IgAV. She experienced prolonged abdominal pain, which was steroid-resistant. When treatment with colchicine was started, her abdominal pain resolved immediately. The serum interleukin (IL)-18 levels of the patient and other patients with IgAV and familial Mediterranean fever (FMF) were evaluated using enzyme-linked immunosorbent assay. The serum IL-18 level of the patient was higher than that of other patients with IgAV and was similar to that of patients with FMF harboring M694I mutation. Moreover, all exons of the MEFV gene were analyzed using the Sanger sequencing and the patient presented with E148Q/M694I mutation. Further, a comprehensive search of Japanese patients with IgAV harboring MEFV gene mutations in PubMed, Ichushi-Web, and Medical Online was conducted to validate the clinical characteristics of Japanese patients with IgAV harboring MEFV gene mutation. In previous studies, only five patients presented with IgAV harboring MEFV gene mutation in Japan.  The prevalence of IgAV associated with MEFV gene mutation may be low in Japan. However, MEFV gene mutations should be suspected if the symptoms of IgAV are prolonged or if patients are refractory to treatment. In such case, IL-18 monitoring and colchicine treatment may be useful for IgAV with MEFV gene mutation.

IgA vasculitis update: Epidemiology, pathogenesis, and biomarkers

Immunoglobulin A vasculitis (IgAV), formerly known as Henoch-Schönlein purpura, is the most common systemic vasculitis in children, characterized by diverse clinical manifestations with a wide spectrum ranging from isolated cutaneous vasculitis to systemic involvement. The incidence of IgAV is geographically and ethnically variable, with a prevalence in autumn and winter, suggesting a driving role that genetic and environmental factors play in the disease. Although IgAV has a certain degree of natural remission, it varies widely among individuals. Some patients can suffer from severe renal involvement and even progress to end-stage renal disease. Its pathogenesis is complex and has not been fully elucidated. The formation of galactose-deficient IgA1 (Gd-IgA1) and related immune complexes plays a vital role in promoting the occurrence and development of IgAV nephritis. In addition, neutrophil activation is stimulated through the binding of IgA to the Fc alpha receptor I expressed on its surface, resulting in systemic vascular inflammation and tissue damage. Starting from the epidemiological characteristics, this article will review the role of immunological factors such as Gd-IgA1, autoantibodies, circulating immune complexes, complement system, cellular immunization, and the contributions of environmental and genetic factors in the pathogenesis of IgAV, and conclude with the major biomarkers for IgAV.

Pathogenesis of IgA Vasculitis: An Up-To-Date Review

Immunoglobin A (IgA) vasculitis (IgAV), formerly called the Henoch-Schönlein purpura (HSP), is a small vessel vasculitis, characterized by IgA1-dominant immune deposition at diseased vessel walls. IgAV is the most common form of vasculitis in children; typical symptoms include palpable purpura, arthritis or arthralgia, abdominal pain, and hematuria or proteinuria. Galactose-deficient IgA1 is detected in the tissues of the kidney and skin in patients with IgAV; it forms immune complexes leading to subsequent immune reactions and injuries. This report provides the recent advances in the understanding of environmental factors, genetics, abnormal innate and acquired immunity, and the role of galactose-deficient IgA1 immunocomplexes in the pathogenesis of IgAV.

Familial Mediterranean fever: What associations to screen for?

Familial Mediterranean fever (FMF) is the most common and best known of hereditary recurrent fever or periodic fever syndromes. It was described in 1945 and genetically characterized in 1992. It is caused by a point mutation in the MEFV gene located on the short arm of chromosome 16. It is particularly frequent among Sephardic Jews, Armenians, Turks and Middle Eastern Arabs, where the prevalence can reach 1/2000 to 1/1000.

Recent publications described its frequent association with other diseases and/or syndromes, particularly those of autoimmune, genetic, and autoinflammatory origin.

The objective of this review is to familiarize healthcare professionals with the main associations to look for in patients followed for FMF. The early detection of these associations makes it possible to improve the management and the prognosis of patients with FMF.

MEFV gene mutations in children with Henoch-Schönlein purpura and their correlations-do mutations matter?

OBJECTIVE

To explore the frequency of MEFV gene mutations in children with Henoch-Schönlein purpura who had no prior familial Mediterranean fever diagnosis and to evaluate the association of MEFV mutations with the clinical and laboratory features of Henoch-Schönlein purpura.

METHODS

Data of 1120 patients diagnosed with Henoch-Schönlein purpura were reviewed retrospectively. The spectrum and degree of organ involvement and acute phase reactant levels were documented for each patient. Blood for MEFV gene mutation analysis was obtained either at the time of the Henoch-Schönlein purpura diagnosis or during follow-up visits. Pathological specimens of patients who underwent biopsy (renal/skin) were evaluated with special consideration for immunofluorescent examinations.

RESULTS

Two hundred and thirty-eight (21.3%) patients were found to have one of the MEFV mutations in which exon 10 mutations were the most common (16.7%). Abdominal pain, joint involvement, scrotal involvement, and relapse were more frequent, and acute-phase reactant levels were significantly high in patients with MEFV mutations. More severe characteristics were observed in the presence of homozygous exon 10 mutations. There was no significant association between exon 2 variants and clinical course of Henoch-Schönlein purpura. Patients carrying MEFV mutations did not have significantly higher levels of IgA deposits in the biopsy materials.

CONCLUSION

Henoch-Schönlein purpura in patients with homozygous exon 10 MEFV mutations seems to be more severe than that in patients carrying other mutations. In patients with exon 10 MEFV mutations, Henoch-Schönlein purpura might be considered as an associated presentation of familial Mediterranean fever rather than a separate clinical entity. Key points • p.M694V mutation is more common in Henoch-Schönlein purpura than in the general population. • p.E148Q variants have no impact on clinical symptoms and laboratory findings in Henoch-Schönlein purpura patients. • The majority of Henoch-Schönlein purpura patients with familial Mediterranean fever have no IgA deposits. • Henoch-Schönlein purpura in familial Mediterranean fever patients may be considered as an integral clinical feature of familial Mediterranean fever.

Vasculitis in Systemic Autoinflammatory Diseases

Autoinflammatory diseases (AID) are diseases of the innate immune system, characterized by recurrent episodes of localized or systemic inflammation. Vasculitis may accompany AID. The causes of the association of vasculitis with monogenic AID are still debated. Among the monogenic AID, Familial Mediterranean Fever (FMF) is the most common. IgA-related vasculitis (IgAV) and Polyarteritis Nodosa (PAN) involving small and/or medium-sized vessels have an increased frequency among FMF patients. There are also case reports revealing vasculitic features in Cryopyrin-Associated Periodic Fever Syndrome (CAPS), Tumor Necrosis Factor Receptor-Associated Periodic Syndrome (TRAPS), Mevalonate Kinase Deficiency (MKD), also known as Hyper IgD syndrome (HIDS), Deficiency of IL-1 Receptor Antagonist (DIRA) and Pyogenic Arthritis, Pyoderma gangrenosum, and Acne (PAPA) patients. Central nervous system vasculitis and vasculopathy have been reported in DIRA and PAPA patients whereas small vessel involvement affecting skin has been reported in CAPS, TRAPS, and MKD patients. Alternatively, vasculitis can also be a leading feature especially in the recently defined monogenic AID (Otulipenia, Deficiency of Adenosine Deaminase 2-DADA2, Haploinsufficiency of A20) and interferonopathies (STING-associated vasculopathy with onset in infancy-SAVI). DADA2 often presents as a PAN-like disease. In otulipenia, patients have painful subcutaneous nodules caused by septal panniculitis with small and medium vessel vasculitis. Haploinsufficiency of A20 (also called Familial Behcet-like Autoinflammatory Syndrome) results in a phenotype very similar to the variable vessel vasculitis of Behcet's disease with recurrent oral-genital ulcers, in addition to, skin rash, uveitis, and polyarthritis. SAVI is an autoinflammatory vasculopathy with increased Interferon (IFN) signature, causing severe skin lesions resulting in ulceration, necrosis, and in some cases, amputation. Behcet's Disease (BD) is a multifactorial polygenic AID characterized by recurrent attacks of oral-genital ulcers, skin lesions, uveitis and a unique vasculitis affecting both arteries and veins of all sizes. Many clinical features overlap with other autoinflammatory diseases and overexpression of proinflammatory cytokines is an important feature of the disease.

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.

MEFV mutations in Iranian Azari Turkish patients with Henoch-Schönlein purpura

BACKGROUND/AIM

The aim of the current study was to screen the rate of MEFV mutations in Henoch-Schönlein purpura (HSP) and to investigate the association of these mutations plus clinical symptoms with HSP disease in the Iranian Azari Turkish ethnic group.

MATERIALS AND METHODS

The study groups included 40 unrelated HSP patients and 200 apparently healthy people without any kind of inflammatory diseases as a control group. Molecular screening was performed for eight main mutations, namely M694V, M694I, M680I, V726A, E148Q, R761H, P396S, and R408Q, using polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP), and sequencing.

RESULTS

Out of the 40 studied patients, 27 subjects (67.5%) did not show any mutation, whereas 10 patients (25%) were heterozygotes for one of the following mutations: M694V, M680I, V726A, E148Q. Moreover, three patients (7.5%) were compound heterozygotes for P369S and R408Q. The significant differences between the patient and control groups for M680I, V726A, E148Q, P396S, and R408Q were P = 0.0043, P = 0.0324, P = 0.0145, P = 0.0043, and P = 0.0043, respectively. Furthermore, no significant difference in clinical manifestations was observed between the two groups of patients with and without mutations.

CONCLUSION

Based on the results, MEFV mutations could be considered effective genetic factors for development of HSP in the Iranian Azari Turkish ethnic group.

Efficacy of colchicine in a child with relapsing bullous Henoch-Schönlein purpura

Colchicine is not usually considered a treatment option for cutaneous lesions of Henoch-Schönlein purpura (HSP) in children. We report a case of pediatric HSP with severe chronic and relapsing cutaneous manifestations that were resistant to corticosteroids. Colchicine had remarkable therapeutic efficacy, with positive dechallenge and rechallenge, without any adverse effects.

CONCLUSION

Colchicine should be considered for chronic, severe cutaneous lesions of pediatric HSP.

WHAT IS KNOWN

Colchicine is not usually considered a treatment option for cutaneous lesions of Henoch-Schönlein purpura (HSP) in children. What is New: We report a case of pediatric HSP with severe cutaneous manifestations that responded well to colchicine. Colchicine should be considered for chronic cutaneous lesions of HSP in children.

Relationship between clinical findings and genetic mutations in patients with familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is one of the most frequent genetic diseases encountered in the Mediterranean region. We aimed to investigate the correlation between genetic mutations and the clinical findings in 562 patients with FMF.

METHODS

In this retrospective cross-sectional study conducted with patients' files between 2006, and 2013, reverse hybridization assay for MEFV gene mutations was used and the 12 most frequent mutations were screened. Mutation types and clinical findings were compared with variance analysis.

RESULTS

The mean age was 6.9 ± 3.4 years (range, 1.8-11.6 years). The most common symptom was fever (97.3%). Thirty-four of the patients (6.04%) were admitted with periodic fever only. Of these patients, M694V was the most common mutation type (73.5%). The percentage of the patients predominantly presenting with recurrent abdominal pain was 77.78% and the most frequent mutations were M694V and E148Q. The rate of arthritis and arthralgia was significantly higher in patients with M694V and E148Q mutations. Chest pain was reported more often in patients homozygous for M694V (61.4%). Pericardial effusion was documented in the echocardiography of 10.9% of the 229 children with chest pain. Some patients had both FMF and Henoch Schönlein purpura (HSP), and were more likely to harbor either homozygote M694V or E148Q mutations. The frequency of episodes was higher in patients with homozygous M694V mutations (number of attacks = 4.4 ± 1.6/month). Proteinuria was detected in 106 patients of cases (29.2%), at an average of 854 ± 145 mg/L. Most of the patients with proteinuria and elevated serum amyloid-A had homozygous M694V mutation.

CONCLUSION

The most common mutation in children in Turkey with FMF is the M694V mutation. Recurrent abdominal pain, arthritis or arthralgia, chest pain, and pericarditis were commonly seen in patients with M694V and E148Q mutations.

Non-canonical manifestations of familial Mediterranean fever: a changing paradigm

Paroxysmal crises of fever and systemic inflammation herald familial Mediterranean fever (FMF), considered as the archetype of all inherited systemic autoinflammatory diseases. Inflammatory bouts are characterized by short-term and self-limited abdominal, thoracic, and/or articular symptoms which subside spontaneously. Erysipelas-like findings, orchitis, and different patterns of myalgia may appear in a minority of patients. In recent years, many non-classical manifestations have been reported in the clinical context of FMF, such as vasculitides and thrombotic manifestations, neurologic and sensory organ abnormalities, gastrointestinal diseases, and even macrophage activation syndrome. As FMF left unrecognized and untreated is ominously complicated by the occurrence of AA-amyloidosis, it is highly desirable that diagnosis of this autoinflammatory disorder with its multiple clinical faces can be contemplated at whatever age and brought forward.

MEFV gene mutations in Egyptian children with Henoch-Schonlein purpura

BACKGROUND

Due to an increased frequency of vasculitis in FMF patients, many investigators have studied MEFV mutations in patients with HSP. The aim of the study is to investigate the frequency and clinical significance of MEFV mutations in Egyptian children with Henoch-Schonlein purpura (HSP). Investigating MEFV mutations in controls may help in estimating the prevalence of MEFV mutation carrier rate in Egyptian children.

METHODS

The study enrolled 90 individuals, sixty children with Henoch-Schonlein purpura (HSP), together with 30 sex-and age-matched apparently healthy controls. The entire study group was screened for 12 common MEFV mutations using a reverse hybridization assay of biotinylated PCR products.

RESULTS

Patients with HSP had a significantly higher frequency of MEFV mutations (61.7%), when compared to the apparently healthy control population (36.7%). V726A was the most frequent mutation with an allelic frequency of 10.8%. Ninety- one percent of patients with MEFV mutations were heterozygous for one mutation, while 8.1% had a compound heterozygous MEFV gene mutations. The mutation V726A, followed by E148Q, were the leading mutations, present in 16.6% and in 13.3% of controls.

CONCLUSIONS

MEFV mutations may be related to HSP susceptibility in children. The mutations were not associated with any clinical and laboratory manifestations. Screening for MEFV mutations in larger number of HSP children may be beneficial to evaluate any possible relationship between certain types of MEFV mutations and HSP, and compare the HSP MEFV mutations to the types of MEFV mutations associated with FMF.

MEFV gene mutations in Turkish children with juvenile idiopathic arthritis

Mutations of the Mediterranean fever (MEFV) gene, which encodes pyrin protein, leads to familial Mediterranean fever (FMF) and a connection between MEFV mutations and rheumatic diseases has been suggested. The aim of this study was to explore the frequency and clinical significance of MEFV mutations in children with juvenile idiopathic arthritis (JIA). In this study, children with JIA, who had no typical symptoms of FMF, were screened for the mutations in exons 2 and 10 of the MEFV gene by direct sequencing. A total of 96 children, 56 girls (58.3%), with a median age of 11 years (2-18 years) were included. Patients were classified according to JIA subgroups as oligoarthritis in 43 (44.8%), rheumatoid factor-negative polyarthritis in 22 (22.9%), rheumatoid factor-positive polyarthritis in 2 (2.1%), systemic arthritis in 12 (12.5%) patients, enthesitis-related arthritis in 16 (16.7%), and psoriatic arthritis 1 (1.04%). A total of 31 children (32.3%) had MEFV mutations: 25 heterozygous, 2 homozygous, and 4 compound heterozygous. There were 22 (11.4%) exon 10 mutations (M694V, R761H, K695R, V726A, R653H) and 15 (7.8%) exon 2 mutations (E148Q, G304R, E148V, T267I). The allele frequencies of MEFV mutations were found to be 19.27%, which is higher than the general population [p = 0.03, (odds ratio (OR):1.93, 95% confidence interval (CI): 1.09-3.41)]. MEFV mutation carrier rates were significantly higher in antinuclear antibody (ANA) negative than in ANA positive patients [p = 0.01, (OR: 0.25, 95% CI: 0.085-0.74)] and in males than in females [p = 0.001, (OR: 0.197, 95% CI: 0.078-0.495)]. Also, there was a statistically significant difference between the MEFV mutation carrier rates and the subgroups of JIA (p = 0.005).

CONCLUSION

These findings suggest that mutations of the MEFV gene may be responsible for rheumatic diseases other than FMF, and patients with JIA especially males, ANA negatives, and ERA subgroups should be screened for MEFV gene mutations in countries where FMF is frequent.