Abstract
Objective
This study aimed to investigate the frequency in which familial Mediterranean fever (FMF) coexists with other diseases and determine whether Mediterranean fever (MEFV) gene mutations are involved in such coexistence.
Material and Methods
In total, 142 consecutive patients with FMF investigated for MEFV mutation were enrolled in this study [Female: 87; Male: 55, mean age 32±12 years (11–62)]. All the patients were questioned for the presence of concurrent disorders, and the medical records of these patients were revised retrospectively. A previous diagnosis of inflammatory disorder other than FMF was considered true if it met the relevant criteria. MEFV mutations were divided into 2 groups, namely M694V and its subgroup (homozygous or heterozygous) (Group I) and others (Group II). Compound heterozygosity for M694V mutation was included in Group II to form a homogeneous group for Group I. Group I and Group II were compared according to phenotypical features. The presence of MEFV mutation was investigated in exons 2, 3, 5, and 10 by the multiplex-PCR reverse hybridization method.
Results
Concomitant disorders were found in 17 of 73 patients with FMF (23%) in Group I and 5 of 56 patients (8.9%) in Group II (p=0.04). Concomitant disorders in Group I were as follows: 7 cases of amyloidosis, 2 cases of Behcet’s disease (BD), 4 cases of ankylosing spondylitis (AS), 1 case of antiphospholipid syndrome, 1 case of Henoch–Schonlein purpura (HSP), 1 case of combination of psoriatic arthritis, HSP, and membranoproliferative glomerulonephritis, and 1 case of AS and amyloidosis. In Group II, the following disorders were found: 1 case of amyloidosis, 1 case of BD, 1 case of AS, 1 case of ulcerative colitis, and 1 case of vitiligo.
Conclusion
The presence of M694V mutation may predispose patients with FMF to developing other inflammatory disorders.
Keywords: Familial Mediterranean fever, Behcet’s disease, amyloidosis, spondylarthropathy
Introduction
Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurrent serositis and fever attacks. The disease is caused by mutations in a gene named Mediterranean fever (MEFV), which encodes a protein called pyrin. This protein is likely to have a downregulating influence on the response of neutrophils to inflammatory stimuli (1).
It has been suggested that MEFV mutations facilitate a heightened inflammatory response that may be beneficial against a microorganism or a specific organism (2). Nonetheless, it has been suggested that enhanced inflammation could predispose patients with FMF to some chronic inflammatory conditions. Some inflammatory disorders, including Henoch–Schonlein purpura (HSP), polyarteritis nodosa (PAN), Behcet’s disease (BD), inflammatory bowel diseases, and multiple sclerosis, are also widely observed in FMF (3). MEFV mutation modifies not only the clinical presentation of FMF but also other inflammatory disorders. However, the role of MEFV mutations in FMF co-existing with other inflammatory disorders remains to be ascertained. This study aimed to investigate the frequency in which FMF coexists with other diseases and to determine whether MEFV mutations are involved in such coexistence.
Material and Methods
Patients
In total, 142 consecutive patients with FMF investigated for MEFV mutation were enrolled in this study [Female: 87; Male: 55, mean age 32±12 years (11–62)]. They were diagnosed on the basis of the Tel–Hashomer diagnostic criteria (4). The study was approved by the local ethics committee. All patients provided informed consent to participate in the study, according to the guidelines of the Declaration of Helsinki. All the patients were questioned for the presence of concurrent disorders, and the medical records of these patients were revised retrospectively. A previous diagnosis of a disorder was considered true if it met the relevant criteria.
Mediterranean fever mutations were divided into 2 groups, namely M694V and its subgroup (homozygous or heterozygous) (Group I) and others (Group II). Compound heterozygosity for M694V mutation was included in Group II to form a homogeneous group for Group I. Group I and Group II were compared according to phenotypical features.
The severity score was calculated according to the Tel–Hashomer severity score (5). This includes mild disease (2–5 points), moderate disease (6–10 points), and severe disease (over 10 points).
The diagnosis of amyloidosis was based on histological proof of congophilic fibrillar deposits in renal biopsy specimens.
Mutation analysis
DNA was extracted from peripheral blood leukocytes using standard protocols (Invisorb® Spin Blood Kit, STRATEC Molecular GmbH, D-13125; Berlin, Germany). Molecular analyses were performed within the framework of routine genetic testing. The presence of MEFV mutation was investigated in exons 2, 3, 5, and 10 by the multiplex-PCR reverse hybridization method.
Statistical analysis
Statistical analysis was performed using the Statistical Package for Social Science (SPSS) software, version 15.0 statistical package program (IBM Inc.; Chicago, IL, USA). Demographic and clinical variables were summarized as proportions. Chi-square testing was performed for the comparison of categorical variables. A p value<0.05 was considered statistically significant.
Results
In total, 129 of the 142 patients with FMF had positive mutation for MEFV gene (90.8%), but 13 of them showed no such mutation (9.2%) (Table 1). M694V and its subgroup mutations (Group I) and other mutations (Group II) were found in 73 (56.6%) and 56 (43.4%) patients with FMF, respectively.
Table 1.
MEFV mutations and their distribution in 142 patients with FMF
| Mutations | N | % |
|---|---|---|
| Group I | 73 | |
| M694V/M694V | 37 | 23.7 |
| M694V/− | 36 | 23.1 |
| Group II | 56 | |
| E148Q/E148Q | 2 | 1.3 |
| E148Q/− | 3 | 1.9 |
| V726A/V726A | 1 | 0.6 |
| V726A/− | 3 | 1.9 |
| M680I/M680I | 4 | 2.6 |
| M680I/− | 3 | 1.9 |
| M694I/E148Q | 1 | 0.6 |
| M680I/V726A | 8 | 5.1 |
| M694V/M680I | 4 | 2.6 |
| M680I/E148Q | 4 | 2.6 |
| M694V/V726A | 7 | 4.5 |
| M694V/R761H | 6 | 3.8 |
| M694I/V726A | 2 | 1.3 |
| M694V/K695R | 1 | 0.6 |
| K695R/− | 1 | 0.6 |
| M694V/E148Q | 3 | 1.9 |
| M694I/R761H | 1 | 0.6 |
| V726A/R761H | 1 | 0.6 |
| E148Q/M694V/V726A | 1 | 0.6 |
| Mutation (−) | 13 | 9.1 |
| TOTAL | 142 | 100 |
MEFV: Mediterranean fever; FMF: familial Mediterranean fever
Concomitant disorders were found in 17 patients with FMF (23%) in Group I and 5 FMF (8.9%) patients in Group II (p=0.04). Concomitant disorders in Group I were as follows: 7 cases of amyloidosis, 2 cases of BD, 4 cases of ankylosing spondylitis (AS), 1 case of antiphospholipid syndrome, 1 case of HSP, 1 case of combination of psoriatic arthritis, HSP, and membranoproliferative glomerulonephritis, and 1 case of AS and amyloidosis. In Group II, the following disorders were found: 1 case of amyloidosis, 1 case of BD, 1 case of AS, 1 case of ulcerative colitis, and 1 case of vitiligo. No concurrent disorders could be found in patients with FMF having negative MEFV mutation (Table 2).
Table 2.
MEFV mutations and concurrent disorders in FMF patients
| MEFV Mutation (+) (n=129) | Concurrent disorders | |
|---|---|---|
| Group I (n=73) | n=17 (23%)* | |
|
| ||
| M694V | 7 AMY | |
| -Hom | 2 BD | |
| -Het | 4 AS | |
| 1 APS | ||
| 1 HSP | ||
| 1 PsA+HSP+MPGN | ||
| 1 AS+AMY | ||
|
| ||
| Group II (n=56) | n=5 (8.9%) | |
|
| ||
| Other mutations | 1 AMY | |
| 1 BD | ||
| 1 AS | ||
| 1 UC | ||
| 1 Vitiligo | ||
p<0.04 Group I vs. Group II
Hom: homozygous; Het: heterozygous; AMY: amyloidosis; BD: Behcet’s disease; AS: ankylosing spondylitis; APS: antiphospholipid syndrome; HSP: Henoch–Schonlein purpura; PsA: psoriatic arthritis; MPGN: membranoproliferative glomerulonephritis; UC: ulcerative colitis
There was a significant difference between Groups I and II in the frequency of arthritis and erysipela-like erythema (ELE) (p<0.01 and p<0.001, respectively).
No significant difference was found between Groups I and II in the frequency of fever, abdominal pain, and pleuritic pain (p>0.05).
The number of patients with a higher severity score was significantly higher in Group I (12.9%) than in Group II (4.3%) (p<0.01). No significant differences could be found between Groups I and II in the number of patients with mild and moderate severity scores (p>0.05)
The rate of the familial history for FMF showed no significant difference in Groups I and II (63% vs. 57%, p=0.5).
Discussion
It has been reported that upregulation of the acute phase response among carriers of FMF may enhance their innate immune system and contribute to better resistance to infections (6). On the other hand, in patients with FMF, there is a subclinical inflammation even during attack-free periods, and this continued inflammation conferred by inflammatory response may predispose patients with FMF to other inflammatory disorders such as PAN and HSP (7, 8). It is well known that the presence of M694V allele gives rise to severe disease and amyloidosis in FMF. However, the role of M694V mutations in the development of concurrent disorders in the course of FMF is not well known. Kalyoncu et al. (9) showed that patients who are carriers for MEFV mutations may have a tendency to develop musculoskeletal rheumatologic complaints. Moreover the presence of these mutations may affect their disease course when they develop other rheumatic diseases.
We included Group I patients having only M694V allele (homozygote or heterozygote) to form a homogenous group. The patients with compound heterozygosity for M694V were added to Group II. We considered that this stratification may be a better way to determine whether M694V mutations play a role in concurrent disorders seen in patients with FMF. In line with the literature, the patients with M694V mutations had a severe disease score. Arthritis and ELE were more commonly determined in Group I. Seventeen patients having M694V mutations had concurrent disorders.
The most common concurrent disorder apart from amyloidosis in patients with FMF was AS. Six of 142 patients with FMF (4.2%) had AS. The frequency of AS in Group I was 6.8%. In Group II, AS was found at a frequency of 1.7%. We have previously that 7.3 of 256 patients with FMF had sacroiliitis, which was related to the presence of M694V mutations (10). Akar et al. (11) showed that patients with FMF having sacroiliitis more commonly had M694V mutation compared than those without sacroiliitis.
Kaşifoğlu et al. (12) reported that 8.6% of 2296 Turkish patients with FMF had amyloidosis and amyloidosis was associated with male gender, arthritis, and the presence of M694V genotype. We detected amyloidosis in 9 of 142 (6.3%) patients with FMF.
While amyloidosis was determined only 1 case with FMF in Group II (1.78%), the frequency of amyloidosis in Group I was found to be 10.9%.
The relationship between BD and FMF has been debatable for a long time. Chetrit et al. (13) found 2 patients with BD among 355 patients with FMF and 2 patients with FMF among 53 patients with BD. Sixteen patients with BD were found to have MEFV mutations, and 2 of them had FMF. Based on these results, they suggested that the association between BD-FMF was higher than expected in both directions. However, the small number of patients was a matter of concern in this study. Bakkaloğlu et al. (14) evaluated the presence of associate diseases in 2838 Turkish patients with FMF, and BD was found in 0.5% of patients with FMF. In our study, in Group I, we found 2 patients with FMF accompanied by BD, which is little high compared with the number reported in the literature. In Group II, only one patient with FMF had BD.
It is well known that the presence of MEFV mutation in cases without FMF can modify clinical manifestations of that disease. Atagündüz et al. (15) showed that there is a tendency to develop vascular involvement in BD patients with MEFV mutation.
The association of PAN and HSP with FMF is well known. The prevalence of HSP and PAN in Turkish patients with FMF has been found to be 7% and 1%, respectively (15). The prevalence of HSP in the general population has been found to vary from 0.05% to 0.8% (8, 16). In that study, genotype analysis was not conducted. Tekin et al. (16) investigated the role of MEFV mutations in 11 patients with HSP. They could not find specific MEFV mutations associated with FMF-HSP. In our study, we did not find any patient with PAN. HSP was found in 2 of 142 (1.4%) patients with FMF. These 2 patients had M694V mutations. It is difficult to draw a concrete conclusion from these results because of the small number of patients.
Inflammatory bowel diseases are possibly associated with FMF. Fidder et al. (17) determined 7 patients with Crohn’s disease among 4978 FMF patients. Of 6 patients determined as having MEFV mutations, 3 had homozygosity for M694V, 1 had compound heterozygosity for M694V/V726A, and 1 had heterozygosity for M694V. One patient had no mutation. Yildirim et al. (18) investigated the prevalence of MEFV mutations in patients ulcerative colitis. The mutations were identified in 19 of the 54 (35.2%) patients with ulcerative colitis. Homozygous E148Q was determined in 2 patients (3.7%) and heterozygous E148Q in 17 patients (31.5%) (E148Q 11.1%, M694V 5.6%, V726A 5.6%, K695R 1.8%, M680I 1.8%, and compound heterozygous 5.6%). In our study, we found 1 UC patient in Group II.
Bias is inevitable in our study because the presence of concomitant disorders significantly increases the chance of a disease being detected (Berkon’s bias). The inclusion of disease controls in concurrence studies minimizes the impact of this important bias at least to some degree (19). We could not include a disease control group in this study because of financial problems. The other limitation is that we formed Group 1 from only patients with FMF having homozygosity and heterozygosity for M694V. Compound heterozygosity for M694V was included in Group II. This categorization was made to form a homogenous group.
In conclusion, compared with FMF patients with other mutations, concurrent disorders were frequently determined in patients with FMF having M694V mutations and its subgroups. The patients with M694V mutation and its subgroups (homozygous, heterozygous) more commonly had arthritis, ELE, and a higher severe severity score than those with other mutations. MEFV mutations, particularly M694V mutations, can modify both clinical manifestations of FMF itself and those of other inflammatory disorders. The presence of M694V mutation in addition to other genetic and environmental factors may predispose FMF patients to developing other inflammatory disorders.
Footnotes
Ethics Committee Approval: Ethics committee approval was received for this study from the ethics committee of Eskişehir Osmangazi University School of Medicine (21 May 2010/119).
Informed Consent: Written informed consent was obtained from patients who participated in this study.
Peer-review: Externally peer-reviewed.
Author Contributions: Concept - S.G., C.K.; Design - S.G., C.K.; Supervision - S.G., C.K., D.U.C.; Data Collection and/or Processing - S.G., C.K., D.U.C.; Analysis and/or Interpretation - S.G., C.K.; Literature Search - S.G., C.K.; Writing Manuscript - S.G., C.K., D.U.C.; Critical Review - S.G., C.K., T.K., D.U.C, N.Ş.Y.B.; Other - S.G., C.K.
Conflict of Interest: No conflict of interest was declared by the authors.
Financial Disclosure: The authors declared that this study has received no financial support.
References
- 1.Centola M, Wood G, Frucht DM, Galon J, Aringer M, Farrell C, et al. The gene for familial Mediterranean fever, MEFV, is expressed in early leukocyte development and is regulated in response to inflammatory mediators. Blood. 2000;15:3223–31. [PubMed] [Google Scholar]
- 2.Ozen S, Balci B, Ozkara S, Ozcan A, Yilmaz E, Besbas N, et al. Is there a heterozygote advantage for familial Mediterranean fever carriers against tuberculosis infections: speculations remain? Clin Exp Rheumatol. 2002;20(Suppl 26):S57–8. [PubMed] [Google Scholar]
- 3.Cattan D. MEFV mutation carriers and diseases other than familial Mediterranean fever: Proved and non-proved associations; Putative biological advantage. Current Drug Targets-Inflammation&allergy. 2005;4:105–12. doi: 10.2174/1568010053622948. http://dx.doi.org/10.2174/1568010053622948. [DOI] [PubMed] [Google Scholar]
- 4.Livneh A, Langevitz P, Zemer D, Zaks N, Kees S, Lidar T, Migdal A, et al. Criteria for the diagnosis of familial Mediterranean fever. Arthritis Rheum. 1997;40:1879–85. doi: 10.1002/art.1780401023. http://dx.doi.org/10.1002/art.1780401023. [DOI] [PubMed] [Google Scholar]
- 5.Sohar E, et al. Proceedings of the First International Conference of FMF. Tel Aviv: Freund Publishing House, Ltd; 1997. p. 208. [Google Scholar]
- 6.Chae JJ, Komarow HD, Cheng J, Wood G, Raben N, Liu PP, Kastner DL. Targeted disruption of pyrin, the FMF protein, causes heightened sensitivity to endotoxin and a defect in macrophage apoptosis. Mol Cell. 2003;11:591–604. doi: 10.1016/s1097-2765(03)00056-x. http://dx.doi.org/10.1016/S1097-2765(03)00056-X. [DOI] [PubMed] [Google Scholar]
- 7.Korkmaz C, Ozdogan H, Kasapçopur O, Yazici H. Acute phase response in familial Mediterranean fever. Ann Rheum Dis. 2002;61:79–81. doi: 10.1136/ard.61.1.79. http://dx.doi.org/10.1136/ard.61.1.79. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 8.Ozdogan H, Arisoy N, Kasapçapur O, Sever L, Calişkan S, Tuzuner N, et al. Vasculitis in familial Mediterranean fever. J Rheumatol. 1997;24:323–7. [PubMed] [Google Scholar]
- 9.Kalyoncu M, Acar BC, Cakar N, Bakkaloglu A, Ozturk S, Dereli E, et al. Are carriers for MEFV mutations “healthy”? Clin Exp Rheumatol. 2006;24(Suppl 42):S120–2. [PubMed] [Google Scholar]
- 10.Kaşifoğlu T, Calişir C, Cansu DU, Korkmaz C. The frequency of sacroiliitis in familial Mediterranean fever and the role of HLA-B27 and MEFV mutations in the development of sacroiliitis. Clin Rheumatol. 2009;28:41–6. doi: 10.1007/s10067-008-0980-3. http://dx.doi.org/10.1007/s10067-008-0980-3. [DOI] [PubMed] [Google Scholar]
- 11.Akar S, Soysal O, Balci A, Solmaz D, Gerdan V, Onen F, et al. High prevalence of spondyloarthritis and ankylosing spondylitis among familial Mediterranean fever patients and their first-degree relatives: further evidence for the connection. Arthritis Res Ther. 2013;15:R21. doi: 10.1186/ar4154. [DOI] [PMC free article] [PubMed] [Google Scholar]
- 12.Kasifoglu T, Bilge SY, Sari I, Solmaz D, Senel S, Emmungil H, et al. Amyloidosis and its related factors in Turkish patients with familial Mediterranean fever: a multicentre study. Rheumatology (Oxford) 2014;2014;53:741–5. doi: 10.1093/rheumatology/ket400. http://dx.doi.org/10.1093/rheumatology/ket400. [DOI] [PubMed] [Google Scholar]
- 13.Ben-Chetrit E, Cohen R, Chajek-Shaul T. Familial Mediterranean fever and Behçet’s disease--are they associated? J Rheumatol. 2002;29:530–4. [PubMed] [Google Scholar]
- 14.Bakkaloğlu A, Özen S, Topaloğlu R, Düşünsel R, Şimşek H. Associated diseases in Turkish FMF patients: Are FMF patients Predisposed to develop certain vasculitidies? Clin Exp Rheumatol. 2002;20:S90. [Google Scholar]
- 15.Atagunduz P, Ergun T, Direskeneli H. MEFV mutations are increased in Behçet’s disease (BD) and are associated with vascular involvement. Clin Exp Rheumatol. 2003;21(Suppl 30):S35–7. [PubMed] [Google Scholar]
- 16.Tekin M, Yalçinkaya F, Tümer N, Akar N, Misirlioğlu M, Cakar N. Clinical, laboratory and molecular characteristics of children with Familial Mediterranean Fever-assoiated vasculitis. Acta Paediatr. 2000;89:177–82. doi: 10.1080/080352500750028799. http://dx.doi.org/10.1111/j.1651-2227.2000.tb01212.x. [DOI] [PubMed] [Google Scholar]
- 17.Fidder HH, Chowers Y, Lidar M, Sternberg M, Langevitz P, Livneh A. Crohn disease in patients with familial Mediterranean fever. Medicine (Baltimore) 2002;81:411–6. doi: 10.1097/00005792-200211000-00001. http://dx.doi.org/10.1097/00005792-200211000-00001. [DOI] [PubMed] [Google Scholar]
- 18.Yıldırım B, Tuncer C, Kan D, Tunc B, Demirag MD, Ferda Percın E, et al. MEFV gene mutations and its impact on the clinical course in ulcerative colitis patients. Rheumatol Int. 2011;31:859–64. doi: 10.1007/s00296-010-1380-y. http://dx.doi.org/10.1007/s00296-010-1380-y. [DOI] [PubMed] [Google Scholar]
- 19.Ben-Chetrit E, Yazici H. Thoughts on the proposed links between Behçet’s disease and familial Mediterranean fever. Clin Exp Rheumatol. 2002;20(Suppl 26):S1–2. [PubMed] [Google Scholar]