Juvenile-onset systemic lupus erythematosus and MEFV polymorphism: A case-control association study among Iranian children

INTRODUCTION AND OBJECTIVES

This study is designed to evaluate the potential influences of Mediterranean fever gene (MEFV) gene polymorphism on systemic lupus erythematosus (SLE) in a cohort of juvenile patients. A case-control study was performed on Iranian patients with a mixed ethnicity population.

PATIENTS AND METHODS

Genotypes of 50 juvenile cases, and 85 healthy controls were investigated for identifying M694V and R202Q polymorphism. Genotyping was done utilizing amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to detect M694V and R202Q mutations, respectively.

MAIN FINDINGS

Our study indicates significant differences in the alleles and genotypes frequencies of MEFV polymorphism between SLE patients and healthy controls (P<0.05). Also, an association was found between renal involvement (50% vs. 8.3%, P=0.000, OR=0.91, 95% CI=0.30-0.278) in juvenile SLE patients and M694V polymorphism incident; But there was no association with other clinical manifestations.

PRINCIPAL CONCLUSION

We found a significant association between R202Q and M694V polymorphism of the MEFV gene and susceptibility to SLE in the studied population; However, further studies on detailed characterization of these polymorphisms' impacts on the key elements responsible for SLE pathogenesis is of great importance.

Co-occurrence of familial Mediterranean fever with systemic lupus erythematosus in South Asian population

BACKGROUND AND OBJECTIVE

Familial Mediterranean fever (FMF) and systemic lupus erythematosus (SLE) are autosomal recessive auto-inflammatory diseases, triggered by FMF-associated gene mutations and auto-antigens. The literature on the co-occurrence of these two disorders is limited to case reports and their correlation is considered rare. We investigated the proportion of FMF among SLE patients when compared with a healthy adult cohort in South Asia.

METHODS

For this observational study, data from our institutional database were collected for the patients diagnosed with SLE. The control group was randomly selected from the database and were age- matched for SLE. The overall proportion of FMF among patients with and without SLE was considered. Student's t-test, Chi-square, and ANOVA were used for univariate analysis.

RESULTS

The study population included 3623 SLE patients and 14,492 controls. In the SLE group, there was a significantly higher proportion of FMF patients compared with the non-SLE group (1.29% vs. 0.79% respectively; p=0.015). SLE was prevalent in Pashtun's (50%) in the middle socioeconomic group while FMF was dominant in Punjabi's and Sindhi's (53%) in the low socioeconomic class.

CONCLUSION

This investigation demonstrates that FMF is more prevalent in a South-Asian population cohort of SLE patients.

The coexistence of familial Mediterranean fever (FMF) in systemic lupus erythematosus (SLE) patients - A cross sectional study

BACKGROUND

Systemic lupus erythematosus (SLE) is a systemic autoimmune inflammatory disease characterized by antibody production against a myriad of autoantigens. Familial Mediterranean fever (FMF) is a genetic autoinflammatory disorder, triggered by FMF-associated point genes mutations. It has been hypothesized that the two conditions rarely coexist.

AIM

The aim of this study was to examine the proportions of FMF among SLE patients compared with the general population without SLE. We hypothesized that the proportion of FMF among SLE patients might be higher than the general population.

METHODS

To conduct this cross-sectional study, data of adult patients with a physician diagnosis of SLE were retrieved from Clalit Health Services database, the largest Health Maintenance Organization in Israel, serving 4,400,000 members. Chi-square and T-test was used for univariate analysis.

RESULTS

The study population included 4,886 SLE patients and 24,430 age and sex matched controls. Within the SLE group we detected a significantly higher proportion of FMF patients compared with non-SLE controls (0.68% and 0.21% respectively; p < 0.001).

CONCLUSIONS

Our study indicated that FMF is more prevalent in an Israeli population of SLE patients.

A human case of GIMAP6 deficiency: a novel primary immune deficiency

The GTPase of immunity-associated proteins (GIMAPs) are a family of genes believed to contribute to lymphocyte development, signaling, and apoptosis, thus playing an important role in immune system homeostasis. While models of gene derangement have been described in both mice and immortalized cell lines, human examples of these diseases remain exceptionally rare. In this manuscript we describe the first documented human cases of a homozygous deleterious GIMAP6 variant in the GIMAP6 gene and their subsequent clinical and immunological phenotype. In order to interrogate the patients’ immune defect, we performed whole-exome sequencing, western blot, flow cytometry analysis, lymphocyte activation and proliferation studies, cytokine release assays, and apoptosis studies. We found two siblings with a predicted deleterious homozygous variant in the GIMAP6 gene with no expression of GIMAP6 protein on western blot. Patients demonstrated accelerated apoptosis, but largely normal lymphocyte subpopulations, activation and proliferation and cytokine release. There appears to be a spectrum of clinical features associated with deficiency of GIMAP6 protein, with one patient suffering lymphopenia and recurrent sinopulmonary infections, and the other clinically asymptomatic. Biallelic variants in the GIMAP6 gene have now been shown to demonstrate disease in humans. The absence of GIMAP6 protein is associated with a spectrum of clinical manifestations and much remains to be learnt about the pathogenic mechanisms underlying this disease. We suggest that biallelic variants in the gene for GIMAP6 should be considered in children with lymphopenia and recurrent sinopulmonary infections.

The frequency of macrophage activation syndrome and disease course in systemic juvenile idiopathic arthritis

Objectives: The aim of this study was to demonstrate the frequency of macrophage activation syndrome (MAS) in systemic juvenile idiopathic arthritis (sJIA) cases, to compare the laboratory tests at the time of diagnosis of sJIA and MAS and to see whether sJIA cases complicated with MAS follow a more severe disease course in the long-term follow-up.Methods: Files of children with sJIA that were followed between May 2010 and September 2017 were reviewed.Results: The cohort consisted of 53 sJIA cases. Mean duration of follow-up was 39.0 ± 24.1 months. The frequency of MAS was 33.9%. Initial laboratory tests at the time of diagnosis of sJIA were compared in between patients with MAS and without MAS. Only ferritin and fibrinogen levels showed significant differences in between the groups (p < .01). Patients who developed MAS had higher ferritin (4482 mg/dL) and lower fibrinogen (371 mg/dL) values than patients without MAS (ferritin 2060 mg/dL, fibrinogen 466 mg/dL) at the time of diagnosis of sJIA. Long-term follow-up results showed that monocyclic course was observed in 45.2%, polycyclic course in 30.1% and persistent course in 24.5% of the cases. It was seen that patients with MAS segregated equally into three groups.Conclusions: Higher ferritin and relatively lower fibrinogen levels at the time of diagnosis of sJIA may be early warning signs of an impending MAS. sJIA patients who develop MAS do not seem to warrant more guarded prognosis in the long-term follow-up.

The influence of carrying MEFV gene variants on juvenile systemic lupus erythematosus

Juvenile-onset systemic lupus erythematosus (jSLE) patients typically have a more severe disease course than adults with SLE. We aimed to assess the prevalence and disease course of jSLE patients carrying MEFV variants. MEFV variant analyses were performed in 44 jSLE patients and effect of these variants on disease severity and course was analyzed by SLEDAI score and SLICC/ACR index. Ten of the patients (22.7%) had a MEFV variant. The median (min-max) SLEDAI score and SLICC/ACR index were 2(0-13) and 0(0-3), respectively. Median age at disease onset, disease duration, SLICC/ACR indexes, SLEDAI scores, clinical and laboratory findings of the patients were comparable in carriers of variants and non-carriers. Nineteen patients (43.2%) had biopsy-proven lupus nephritis and four of these patients had MEFV variants. There was no significant difference between patients with and without MEFV carriers in terms of lupus nephritis. Even though not significant statistically, renal involvement was milder in MEFV carriers than non-carriers. The presence of MEFV variants does not increase the overall susceptibility to jSLE in our cohort, while larger number of patients is required to display the protective role of MEFV variants in jSLE.

Coexistence of Mixed Connective Tissue Disease and Familial Mediterranean Fever in a Japanese Patient

We herein report a Japanese patient with familial Mediterranean fever (FMF) who developed the clinical manifestations of mixed connective tissue disease (MCTD) and Sjögren's syndrome. The patient was a 36-year-old woman presenting with a periodic short-duration (2-3 days) fever and pleural pain. An Mediterranean fever (MEFV) gene analysis detected a complex allele mutation (P369S/R408Q) in exon 3 of the MEFV gene. Serological and clinical data showed the coexistence of MCTD and Sjögren's syndrome. Treatment with colchicine (1.0 mg/day) successfully eliminated febrile attack and pleuritis, leading to the diagnosis of FMF. Four months after the initiation of colchicine treatment, she presented with MCTD-related pulmonary artery hypertension. This is the first report of FMF coexisting with MCTD.

A case of adult onset Still's disease with mutations of the MEFV gene who is partially responsive to colchicine

RATIONALE

Familial Mediterranean fever (FMF) and adult onset Still's disease (AOSD) have overlapping features, and are categorized as being on the spectrum of autoinflammatory diseases (AIDs). FMF is more prevalent in the Mediterranean region but rarely, described in the Chinese population.

PATIENT CONCERNS

We present an interesting case of a Han Chinese AOSD patient with episodic fever, wheals, and polyarthritis for 2 years.

DIAGNOSIS

Sequencing analysis found exon 2 mutations of the MEFV gene (c.329T>C [L110P], and c.442G>C [E148Q]).

INTERVENTION

Her arthritis was well-controlled with colchicine treatment, but fever, and rashes were not.

OUTCOMES

She eventually received tocilizumab, in addition to colchicine, and her symptoms completely disappeared.

LESSONS

MEFV mutations may exist in AOSD patients, and treatment with colchicine might be helpful in such patients.

Familial Mediterranean fever is no longer a rare disease in Japan

Background

The aim of this study was to evaluate the clinical manifestations and prevalence of familial Mediterranean fever (FMF) in Japanese patients with unexplained fever and rheumatic manifestations.

Methods

We enrolled 601 patients with unexplained fever or suspected FMF throughout Japan between 2009 and 2015. Patients were divided into three groups according to Tel Hashomer criteria: sure FMF, probable FMF, and non-FMF patients, including definitive rheumatic diseases. Mutation detection in exons 1, 2, 3, and 10 of the FMF gene MEFV was performed by direct sequencing.

Results

A total of 192 patients (31.9 %) were diagnosed with FMF according to FMF diagnostic criteria. These could be divided into sure FMF (56.3 %, n = 108) and probable FMF (43.7 %, n = 84) patients. Fever, abdominal symptoms, and thoracic symptoms were significantly more common in FMF than non-FMF patients. Among FMF patients, 26 (13.5 %) had concomitant rheumatic diseases. Most FMF patients (94.3 %, 181/192) carried at least one MEFV mutation. Allele frequencies of M694I (13.5 % vs 0 %) and E148Q (39.1 % vs 24.8 %) mutations were significantly higher in FMF compared with healthy subjects. Allele frequencies of common MEFV mutations in FMF patients were M694I (13.5 %), P369S (8.6 %), R408Q (8.1 %), G304R (2.9 %), R202Q (4.4 %), E148Q (39.1 %), L110P (11.7 %), and E84K (3.1 %). Patients with a sure FMF phenotype had a higher frequency of MEFV exon 10 mutation (M694I) and a lower frequency of MEFV exon 3 mutations (P369S, R408Q) compared with those with a probable FMF phenotype.

Conclusion

The high prevalence of FMF in Japanese patients with unexplained fever was confirmed in the present study. FMF should be suspected in cases of unexplained fever or non-specific rheumatic manifestations, and mutational analysis of MEFV could be useful to predict the clinical phenotypes of FMF in Japan.

Intestinal malrotation as a misdiagnosis of pediatric colchicine resistant familial Mediterranean fever

BACKGROUND

Familial Mediterranean fever (FMF) is a disorder characterized by recurrent attacks of fever and serosal inflammation, particularly abdominal pain. Other disease processes, including medical and surgical emergencies, may mimic FMF, especially in atypical cases.

CASE PRESENTATION

We present a case of an adolescent male, referred to us with a diagnosis of colchicine resistant FMF, ultimately diagnosed with intestinal malrotation and recurrent volvulus.

CONCLUSIONS

In atypical presentations of FMF with potential "red flags", a thorough patient history is extremely important and should result in prompt referral for the appropriate diagnostic tests.

Familial Mediterranean fever gene (MEFV) mutations and disease severity in systemic lupus erythematosus (SLE): implications for the role of the E148Q MEFV allele in inflammation

OBJECTIVE

Observed low prevalence of SLE among familial Mediterranean fever (FMF) patients in several large cohorts suggests a possible protective effect of the MEFV mutations from SLE. In contrast, SLE patient carriers for the common MEFV mutations had rather complex disease expression with an increased frequency of febrile episodes and pleurisy and a decreased renal complication rate. Our aim was to investigate the prevalence of MEFV gene mutations in patients with SLE and their effect on organ involvement in a well-defined group of biopsy-proven SLE nephritis patients.

MATERIAL AND METHOD

The prevalence of four MEFV gene mutations (M694V, M680I, V726A and E148Q) was investigated in 114 SLE patients and effect on disease severity was analyzed in patients with biopsy-proven SLE nephritis.

RESULTS

None of the SLE patients fulfilled the revised Tel-Hashomer criteria. Fourteen of 114 SLE patients (12.2%) were found to carry at least one MEFV mutation. A single patient in the SLE-Nephritis group was compound heterozygous for M694V/M680I mutations and only one patient in the SLE-Mild group was homozygous for E148Q mutation. Carrier frequency was similar to controls in SLE patients (12.2 vs 18.8%, p = 0.34). After the exclusion of the less penetrant E148Q mutation, re-analysis revealed an association between exon 10 mutations and SLE nephritis (p = 0.050, odds ratio (OR) = 4.16, 95% confidence interval (CI) = 1.04-16.6). Carrier rate for the E148Q mutation decreased in the SLE group (controls vs. SLE = 20/186 vs. 3/114, p = 0.08) and E148Q mutation was absent in SLE nephritis (controls vs. SLE nephritis = 20/186 vs. 0/47, p = 0.016, OR = 11.69, 95% CI = 0.69-197.13).

CONCLUSIONS

Carrier rate for the studied MEFV mutations was slightly lower in the SLE group, which is in agreement with previous observations that FMF may confer some protection from SLE. Exon 10 mutations were associated with SLE nephritis after the exclusion of the E148Q mutation. The significance of the E148Q as a disease-causing mutation is controversial, and whether E148Q substitution is a polymorphism generally affecting inflammatory pathways is not addressed in the current literature. In this regard, absence of the E148Q mutation in SLE nephritis may serve as a clue for further investigation into its role as a general modulatory polymorphism for inflammation. This clarification is necessary to conclude whether other more penetrant MEFV gene mutations confer susceptibility to nephritis in SLE.

Genome-wide association study combined with biological context can reveal more disease-related SNPs altering microRNA target seed sites

Background

Emerging studies demonstrate that single nucleotide polymorphisms (SNPs) resided in the microRNA recognition element seed sites (MRESSs) in 3′UTR of mRNAs are putative biomarkers for human diseases and cancers. However, exhaustively experimental validation for the causality of MRESS SNPs is impractical. Therefore bioinformatics have been introduced to predict causal MRESS SNPs. Genome-wide association study (GWAS) provides a way to detect susceptibility of millions of SNPs simultaneously by taking linkage disequilibrium (LD) into account, but the multiple-testing corrections implemented to suppress false positive rate always sacrificed the sensitivity. In our study, we proposed a method to identify candidate causal MRESS SNPs from 12 GWAS datasets without performing multiple-testing corrections. Alternatively, we used biological context to ensure credibility of the selected SNPs.

Results

In 11 out of the 12 GWAS datasets, MRESS SNPs were over-represented in SNPs with p-value ≤ 0.05 (odds ratio (OR) ranged from 1.1 to 2.4). Moreover, host genes of susceptible MRESS SNPs in each of the 11 GWAS dataset shared biological context with reported causal genes. There were 286 MRESS SNPs identified by our method, while only 13 SNPs were identified by multiple-testing corrections with a given threshold of 1 × 10⁻⁵, which is a common cutoff used in GWAS. 27 out of the 286 candidate SNPs have been reported to be deleterious while only 2 out of 13 multiple-testing corrected SNPs were documented in PubMed. MicroRNA-mRNA interactions affected by the 286 candidate SNPs were likely to present negatively correlated expression. These SNPs introduced greater alternation of binding free energy than other MRESS SNPs, especially when grouping by haplotypes (4210 vs. 4105 cal/mol by mean, 9781 vs. 8521 cal/mol by mean, respectively).

Conclusions

MRESS SNPs are promising disease biomarkers in multiple GWAS datasets. The method of integrating GWAS p-value and biological context is stable and effective for selecting candidate causal MRESS SNPs, it reduces the loss of sensitivity compared to multiple-testing corrections. The 286 candidate causal MRESS SNPs provide researchers a credible source to initialize their design of experimental validations in the future.

Electronic supplementary material

The online version of this article (doi:10.1186/1471-2164-15-669) contains supplementary material, which is available to authorized users.