Human leucocyte antigens and Japanese patients with polymyalgia rheumatica: the protective effect of DRB1*09:01

OBJECTIVE

The hallmarks of the chronic inflammatory disease polymyalgia rheumatica (PMR) include pain, and morning stiffness in areas of the neck, shoulder and pelvic girdle. The human leucocyte antigen (HLA) gene was reported to be an important risk factor for PMR, but it has not been analysed precisely, especially in populations other than Europeans.

METHODS

Genotyping of DRB1 and DQB1 was performed in Japanese PMR patients (n=270) and controls (n=413). Associations between allele carrier and genotype frequencies were determined for PMR.

RESULTS

DRB1*04:05 was associated with a predisposition to PMR (p=0.0006, Pc=0.0193, OR 1.85, 95% CI 1.31 to 2.62). DRB1*09:01 was associated with protection against PMR (p=1.46×10-5, Pc=0.0004, OR 0.40, 95% CI 0.26 to 0.61). A shared epitope (SE) associated with PMR (p=3.07×10-6, OR 2.11, 95% CI 1.54 to 2.88). DQB1*03:03 (p=0.0010, Pc=0.0140, OR 0.52, 95% CI 0.35 to 0.77) was associated with protection against PMR and DQB1*04:01 (p=0.0009, Pc=0.0140, OR 1.82, 95% CI 1.28 to 2.58) was associated with predisposition to PMR. A gene dosage effect was observed for DRB1*09:01 and DQB1*03:03, but not for DRB1*04:05, SE or DQB1*04:01. Haplotype and logistic regression analyses suggested a protective effect for DRB1*09:01.

CONCLUSION

This study is the first to demonstrate predisposing associations of DRB1*04:05, SE, and DQB1*04:01, and protective associations of DRB1*09:01 and DQB1*03:03 with PMR in Japanese patients. Our data indicate HLA has predisposing and protective effects on the pathogenesis of PMR.

The contributions of deleterious rare alleles in NLRP12 and inflammasome-related genes to polymyalgia rheumatica

Polymyalgia rheumatica (PMR) is a chronic inflammatory disease characterized by arthralgia and myalgia of the shoulder and hip girdles, and fever. PMR is linked to autoimmune diseases and autoinflammatory disorders. Exome sequencing has revealed the roles of rare variants in some diseases. Causative genes for monogenic autoinflammatory disorders might be candidate genes for the selective exome analysis of PMR. We investigated rare variants in the coding and boundary regions of candidate genes for PMR. Exome sequencing was performed to analyze deleterious rare variants in candidate genes, and the frequencies of the deleterious rare alleles in PMR were compared with those of Japanese population controls. Deleterious rare alleles in the NLRL12 gene were associated with PMR (P = 0.0069, Pc = 0.0415, odds ratio [OR] 4.49, 95% confidence interval [CI] 1.79-11.27). A multigene analysis demonstrated the deleterious rare allele frequency of the candidate genes for autoinflammatory disorders was also increased in PMR (P = 0.0016, OR 3.69, 95%CI 1.81-7.54). The deleterious rare allele frequencies of the candidate genes including NLRP12 were increased in PMR patients, showing links to autoinflammatory disorders in the pathogenesis of PMR.

[A Case of Essential Thrombocythemia with a JAK2V617F Mutation andPolymyalgia Rheumatica]

A patient with polymyalgia rheumatica(PMR)had increasing thrombocytosis. CRP levels, the ESR, and serum interleukin (IL)-6 levels were slightly elevated, and the patient tested negative for RF and anti CCP antibodies. Muscle pain was ameliorated with the administration of corticosteroids. Genetic analysis of the peripheral white blood cells demonstrated the presence of a JAK2V617F mutation. The muscle pain experienced by the patient was considered to be due to essential thrombocythemia( ET)of myeloproliferative neoplasms(MPNs)along with an inflammatory reaction. Unfortunately, the patient died suddenly because of cerebral infarction.

T-786C single nucleotide polymorphism of the endothelial nitric oxide synthase gene as a risk factor for endothelial dysfunction in polymyalgia rheumatica

OBJECTIVES

We investigated the association of the T-786C single nucleotide polymorphism (SNP) of the endothelial nitric oxide synthase gene (NOS3), which is characterised by reduced expression of the enzyme in response to shear stress or interleukin-10 stimulation and significantly associated with coronary heart disease or rheumatoid arthritis, with the occurrence of isolated polymyalgia rheumatica.

METHODS

A cohort of 78 patients who had presented at a rheumatological specialist practice in Heidelberg was tested for the T-786C SNP by means of restriction fragment length polymorphism analysis, and the result was compared with the data of a control cohort (n=2061) compiled from the genotyping of umbilical cord arteries from newborns. Patients were tested for an association with the genotype and their clinical characteristics obtained at the time of the initial presentation and during the first year of treatment.

RESULTS

The T-786C SNP of the NOS3 gene was significantly associated with isolated PMR (p=0.0009; OR 2.475). The C-allele frequency in patients with PMR was higher than in patients with rheumatoid arthritis, who also showed a significant association with the T-786C SNP (PMR 0.481 vs. 0.422 RA). A significant association with clinical features of the patients could not be detected.

CONCLUSIONS

The T-786C SNP of the NOS3 gene, which predisposes towards the development of endothelial dysfunction, is significantly associated with polymyalgia rheumatica manifesting itself without any clinically detectable vascular involvement.

Influence of interleukin 10 promoter polymorphisms in polymyalgia rheumatica: disease susceptibility and functional consequences

OBJECTIVES

To investigate the functional consequences of IL10 (-592C/A and -1082A/G) gene polymorphisms and their association with susceptibility to, and disease phenotype, in patients with polymyalgia rheumatica (PMR).

METHODS

A total number of 168 with PMR and 124 age-matched controls were genotyped using allele-specific primers and restriction fragment length polymorphism analysis. The levels of circulating IL10 and the production of IL10 by PBMCs after in vitro stimulation were studied by Cytometric Bead Array.

RESULTS

No significant differences were observed in genotype or allele frequency distribution between patients and controls. The clinical characteristics and prognosis of these patients were also unrelated to the presence of these polymorphisms. No significant differences between PMR patients with low ESR (<40 mm/hr) and classic PMR (>40 mm/hr) were found. Furthermore, we did not observe any influence of circulating IL10 with the intensity of the acute phase response. In both, PMR patients and age-matched controls, no differences in circulating IL10 levels or IL10 production were observed depending on the genotypes of the IL10 gene.

CONCLUSIONS

These results do not support the impact of IL10 variants in susceptibility or clinical phenotype of PMR patients. In this aged population no functional association was found between IL10 gene variants and IL10 production.

Analysis of the rs20541 (R130Q) polymorphism in the IL-13 gene in patients with elderly-associated chronic inflammatory diseases

OBJECTIVE

To investigate whether there is association between the rs20541 (R130Q) polymorphism in the IL-13 gene with disease susceptibility and clinical subsets in patients with elderly-associated inflammatory chronic diseases.

MATERIAL AND METHODS

78 patients with giant cell arteritis (GCA), 174 with polymyalgia rheumatica (PMR), 90 elderly-onset rheumatoid arthritis (EORA), and 465 healthy controls from the same geographic area were studied. The rs20541 (R130Q) polymorphism in the IL-13 gene was evaluated by PCR-RFLP. Circulating levels of IL-13 were measured by ELISA.

RESULTS

A higher frequency of the AA genotype [2.349 (0.994-5.554)], as well as the allele A [1.589 (1.085-2.328] and the A carriers [1.656 (1.021-2.686)] (p<0.05) was observed in the GCA patients. No significant differences were observed in the PMR and EORA patients as compared with the healthy controls. Neither difference was observed among the different disease groups studied. In GCA patients, differences in the genotype were associated with a worse prognosis. In PMR patients, the AA genotype was associated with higher levels of serum IL-13 than the GA one. However, such an association was not detected for controls and the other disease groups.

CONCLUSIONS

GCA is more frequent in carriers of the rs20541 (R130Q) polymorphism in the IL-13 gene. The utility of this polymorphism to predict the GCA prognosis must be confirmed in studies with a higher number of patients.

Toll-like receptor 4 gene polymorphisms in polymyalgia rheumatica and elderly-onset rheumatoid arthritis

OBJECTIVES

Coding variants in TLR4 gene have been reported to be associated with inflammatory diseases. The aim of this study was to determine whether two of these polymorphisms (Asp299Gly and Thr399Ile) of TLR4 contribute to the genetic background of polymyalgia rheumatica (PMR) and elderly-onset rheumatoid arthritis (EORA). Furthermore, we have attempted to correlate the functional consequences of these polymorphisms.

METHODS

164 patients with PMR, 93 with EORA and 126 unrelated age-matched controls were genotyped. The TLR4 genotypes were determined using allele-specific primers and restriction fragment length polymorphism analysis. Association of genotypes and alleles with disease susceptibility and disease phenotypes were studied. TLR4 expression was assessed on PBMCs by flow cytometry and TLR4 function was assessed by stimulating PBMCs in vitro with LPS.

RESULTS

No significant difference in allele frequency or genotype between patients with elderly-onset inflammatory conditions and controls was observed. The Thr399Ile CC genotype was associated with a higher cumulative dose of corticosteroids in patients with PMR (p=0.031). We found no association with TLR4 expression on B cells, T cells or monocytes or a distinct phenotype of TLR4 response with the Asp299Gly or Thr399Ile genotypes.

CONCLUSIONS

These results do not support the association of these TLR4 variants with two age-related inflammatory conditions. The value of determining Thr399Ile genotypes for disease prognosis in PMR should be confirmed in different populations.

Interleukin-12 gene polymorphisim in patients with giant cell arteritis, polymyalgia rheumatica and elderly-onset rheumatoid arthritis

OBJECTIVE

The cytokine profile suggests that giant cell arteritis (GCA) is a Th1-driven disease, in which local IFN-gamma plays a critical role in the development of a systemic arteritis. IL-12 is a potent inducer of IFN-gamma and is critically involved in biasing an immune response towards a Th1 pathway. The purpose of this study was to investigate whether there was an association between an IL-12 gene polymorphism (-1188 A/C 3UTR) and disease susceptibility for GCA and two other age-related inflammatory conditions, such as polymyalgia rheumatica (PMR) and elderly-onset rheumatoid arthritis (EORA). Furthermore, we attempted to correlate such polymorphism with in vitro IL-12 production.

MATERIALS AND METHODS

We analyzed genotypes at -1188 in the 3UTR of the IL-12 promoter by PCR-RFLP in 68 GCA, 138 PMR, and 72 EORA patients as well as in 465 healthy controls (HC). IL-12p70 levels in culture supernatants after stimulation with PMA+Ionomycin was assessed by ELISA.

RESULTS

All groups were in Hardy-Weinberg equilibrium. Allelic and gen-omic distribution was not significantly different among the study groups. None of the genetic variants was associated with disease severity. Although the differences were not statistically significant, HC genotypes were associated with distinct IL-12 p70 production.

CONCLUSIONS

The IL-12 (-1188 A/C 3UTR) gene polymorphism is not associated with disease susceptibility or severity in three age-related chronic inflammatory syndromes. The production of IL-12 p70 is dependent on the genetic background in HC, although in patients such association may be biased by other unknown factors.

Familial aggregation in giant cell arteritis and polymyalgia rheumatica: a comprehensive literature review including 4 new families

OBJECTIVE

To review personal and published observations of giant cell (temporal) arteritis (GCA) or polymyal-gia rheumatica (PMR) with familial or conjugal aggregation and emphasise on epidemiological, clinical and genetic features of such cases.

METHODS

We pooled data obtained from all cases of GCA or PMR with familial aggregation recruited in the department since 1976 and those from reports of familial or conjugal GCA or PMR published in the French-English literature since 1970.

RESULTS

During the study period, we diagnosed 460 patients (128 with isolated PMR, 227 with isolated GCA, 105 with PMR/CGA). No conjugal couples were observed in the whole series. No familial cases were identified among PMR patients, whereas the prevalence of familial GCA was 1 in 83 (1 in 250 to 500 expected by chance), as we identified 4 patients (brother-brother, sister with history of affected sister, and daughter with priory affected mother). An additional pair of sisters with TA, recruited several months after diagnosis, is also presented. Pooling data from 85 patients (74 with GCA) including our patients, representing 32 families and 8 conjugal pairs, enabled us to draw the following observations: 1) partial or full agreement in the clinical picture (GCA, PMR, or GCA/PMR) was observed in 96% of the siblings pairs, suggesting a common pathogenic mechanism; 2) five kindred were described in whom at least three members were affected; 3) the lag between manifested diseases in familial or conjugal pairs averaged 5.7 years, with synchronous or close disease occurrence in only 26% of the pairs; 4) 18 of 32 assessed patients (56%) carried the DR4 antigen.

CONCLUSION

Our survey on familial aggregation of GCA and PMR accumulated data pointing to a genetic predisposition. However, environmental contagious factors could have trigger synchronous disease onset in up to one-fourth of the cases.

Toll-like receptor 4 (TLR4) gene polymorphisms in giant cell arteritis

OBJECTIVE

To investigate potential associations between toll-like receptor 4 (TLR4) gene polymorphisms and susceptibility to, and clinical features of giant cell arteritis (GCA).

METHODS

A total of 155 patients with biopsy-proven GCA who were residents of Reggio Emilia, Italy, and 210 population-based controls from the same geographical area were genotyped for two coding single nucleotide polymorphisms of TLR4 (Asp299Gly and Thr399Ile) by molecular methods. The patients were subgrouped according to the presence or absence of polymyalgia rheumatica and severe ischemic complications (visual loss and/or cerebrovascular accidents).

RESULTS

The distribution of allele and genotype frequencies did not differ significantly between GCA patients and healthy controls. Carriers of the -299 G allele (G/A+ G/G) [odds ratio (OR) 1.78, 95% confidence intervals (CI) 0.90-3.50)] were more frequent among GCA patients than among the controls, but the difference was not statistically significant. No significant associations were found when GCA patients with and without PMR or with and without severe ischemic complications were compared.

CONCLUSION

Our data suggest that the TLR4 gene polymorphisms are not associated with susceptibility to, and clinical expression of, GCA in Italian patients.

-463 G/A myeloperoxidase promoter polymorphism in giant cell arteritis

OBJECTIVE

To investigate potential associations between-463 G/A myeloperoxidase (MPO) promoter polymorphism and susceptibility to, and clinical features of giant cell arteritis (GCA).

METHODS

A total of 156 patients with biopsy-proven GCA who were residents of Reggio Emilia, Italy, and 235 population-based controls from the same geographic area were genotyped for-463 G/A promoter polymorphism of the MPO gene by molecular methods. The patients were subgrouped according to the presence or absence of polymyalgia rheumatica and severe ischaemic complications (visual loss and/or cerebrovascular accidents).

RESULTS

The distribution of the MPO-G/A genotype differed significantly between patients with GCA and the controls (p(corr) = 0.003). Allele G was significantly more frequent in patients with GCA than in the controls (p(corr) = 0.0002, OR 2.0, 95% CI 1.4 to 2.9). Homozygosity for the G allele was significantly more frequent in patients with GCA than in controls (p(corr) = 0.0002, OR 2.2, 95% CI 1.4 to 3.4). No significant associations were found when patients with GCA with and without polymyalgia rheumatica or with and without severe ischaemic complications were compared.

CONCLUSIONS

Our findings show that the-463 G/A promoter polymorphism of the MPO gene is associated with GCA susceptibility and support a role for MPO in the pathophysiology of GCA.

Relationship between interleukin 6 promoter polymorphism at position -174, IL-6 serum levels, and the risk of relapse/recurrence in polymyalgia rheumatica

OBJECTIVE

To assess the role of -174 G/C promoter polymorphism of interleukin 6 (IL-6) in the susceptibility to polymyalgia rheumatica (PMR). We also investigated whether this polymorphism modulates the circulating level of IL-6 and the risk of relapse/recurrence in a series of patients with PMR followed up prospectively.

METHODS

A prospective study of 112 consecutive, untreated patients with isolated PMR (i.e., without evidence of giant cell arteritis) who were followed up for at least 24 months. This cohort represented all patients diagnosed over a 5-year period in one Italian rheumatological secondary referral center. Patients were monitored for clinical signs/symptoms and acute-phase reactants. All PMR patients and 112 population-based controls from the same geographic area were genotyped for IL-6 polymorphism at position -174 by molecular methods. IL-6 serum levels were measured in 67 PMR patients and 43 population-based controls.

RESULTS

The distribution of the G/C 174 genotype was similar in PMR patients and controls. No significant associations with IL-6 promoter polymorphism at position -174 were found when PMR patients with and without relapse/recurrence were compared. Controls homozygous for the C allele had higher serum IL-6 levels than the carriers of the G allele (4.5 +/- 3.7 pg/ml vs 1.8 +/- 2.1 pg/ml, p = 0.01). Patients homozygous for the allele C had significantly higher values of IL-6 during followup than patients carrying GC or GG genotypes. CC homozygosity was significantly more frequent in patients with persistently elevated levels of IL-6 than in those without. The presence of persistently elevated IL-6 levels, but not the CC genotype, was associated with an increased frequency of relapse/recurrence.

CONCLUSION

Our findings show that the 174 G/C promoter IL-6 polymorphism is not implicated in susceptibility to PMR. However, CC genotype characterized PMR patients with persistently elevated levels of IL-6 who are at higher risk of developing relapse/recurrence. A genetically modulated pattern of IL-6 production could affect the longterm outcome of patients with PMR.

Lack of association of a functional -94ins/delATTG NFKB1 promoter polymorphism with susceptibility and clinical expression of biopsy-proven giant cell arteritis in northwest Spain

OBJECTIVE

Giant cell arteritis (GCA) is a vasculitis preferentially involving large and middle-sized arteries in the elderly. The nuclear factor of k-light polypeptide gene enhancer in B cells (NF-kB) is a family of 5 proteins expressed in most cells that function to regulate gene transcription. NFKB1 gene plays a critical role in the coordination of the immune system by regulating the transcription of a broad variety of genes implicated in the immune response. A NFKB1 promoter polymorphism consisting of a common insertion/deletion (-94ins/delATTG) located between 2 putative key promoter regulatory elements and showing functional effects on the transcription of the NFKB1 gene has been described. Since GCA is a polygenic disease, we sought to assess the potential role of the -94ins/delATTG NFKB1 promoter polymorphism in susceptibility to GCA and to determine if this polymorphism is implicated in the clinical expression of this vasculitis.

METHODS

Ninety-six patients with biopsy-proven GCA and 204 ethnically matched Caucasian controls from the Lugo region (Northwest Spain) were studied. Genotyping of the -94ins/delATTG NFKB1 promoter polymorphism was performed by fluorescent polymerase chain reaction (PCR).

RESULTS

No significant differences in allele or genotype frequencies for this NFKB1 promoter polymorphism were observed between patients with GCA and controls even when patients were stratified according to gender, presence of polymyalgia rheumatica (n = 38), severe ischemic manifestations (n = 49), or other clinical manifestations of GCA.

CONCLUSION

Our results do not support a role for -94ins/delATTG NFKB1 promoter polymorphism in susceptibility and clinical expression of GCA in a Northwestern Spanish population.

Interleukin-6 promoter polymorphism at position -174 in giant cell arteritis

OBJECTIVE

To investigate potential associations between the -174 G/C interleukin-6 (IL-6) promoter polymorphism and susceptibility to and clinical features of giant cell arteritis (GCA), particularly in patients with or without polymyalgia rheumatica (PMR) and with or without ischemic complications.

METHODS

One hundred and twenty-six patients with biopsy-proven GCA who were residents in Reggio Emilia, Italy, and 112 population-based controls from the same geographic area were genotyped for IL-6 polymorphism at position -174 by molecular methods. Patients were divided in subgroups according to presence or absence of PMR and ischemic complications (visual loss, jaw claudication, cerebrovascular accidents, aortic arch syndrome).

RESULTS

Distribution of the G/C 174 genotype was similar in patients with GCA and controls. No significant associations with the IL-6 promoter polymorphism at position -174 were found when GCA patients with or without PMR or with or without ischemic complications were compared. Further, IL-6 genotypes did not significantly affect levels of C-reactive protein or other inflammatory markers at diagnosis.

CONCLUSION

Our findings show that the 174 G/C promoter IL-6 polymorphism does not seem to be implicated in susceptibility to and clinical expression of GCA.

Diagnosing late onset rheumatoid arthritis, polymyalgia rheumatica, and temporal arteritis in patients presenting with polymyalgic symptoms. A prospective longterm evaluation

OBJECTIVE

. To examine for demographic and clinical differences between late onset rheumatoid arthritis (LORA), polymyalgia rheumatica (PMR), and temporal arteritis (TA) patients presenting with polymyalgic symptoms (PMS) and to identify baseline clinical and laboratory features that would lead to a more accurate final diagnosis.

METHODS

Three hundred forty-nine consecutive patients with new onset of symptoms suggestive of LORA, PMR, or TA presenting at or above age 60 years were enrolled in a prospective study.

RESULTS

During followup, 9 patients diagnosed initially as PMR developed LORA (giving a final total of 145), 5 patients initially diagnosed as LORA changed diagnosis to PMR (final total 147), and 29 patients had PMS that predated TA symptoms (final total 57). The delay in diagnosis ranged from 1 to 30 months. DRB1*04 was associated with development of both LORA and TA.

CONCLUSION

In about 10% of patients the correct diagnosis of LORA, PMR, and TA in those presenting with PMS may be delayed due to similarities in initial clinical presentation. Longterm followup is essential to establish correct diagnosis. Laboratory tests tend to be unhelpful, although a positive rheumatoid factor or persistently raised plasma viscosity despite steroids might indicate RA, and the presence of HLA-DRB1*04 may indicate underlying RA or TA.

Expression of DARC, CXCR3 and CCR5 in giant cell arteritis

OBJECTIVES

Leucocyte infiltration is the hallmark of vasculitis, chemokines being mainly responsible for leucocyte migration into inflamed tissues. The objective was to evaluate the local expression of chemokines and chemokine receptors in biopsies of patients with giant cell arteritis (GCA) compared with arteries from patients with polymyalgia rheumatica (PMR). We studied the expression of CCR5, CXCR3 and that of the Duffy antigen/receptor of chemokine (DARC), a chemokine internalizing receptor (interceptor), in parallel to the expression of the CCR5 ligand RANTES/CCL5.

METHODS

Paraffin-embedded tissue sections from six patients with GCA and five patients with PMR were available for immunohistological analysis of chemokine receptor expression. RANTES/CCL5 mRNA was detected in tissue sections by in situ hybridization.

RESULTS

In patients with biopsy-proven giant cell arteritis, CCR5 and CXCR3 were highly expressed by infiltrating leucocytes in involved tissue sections. Predominant clustering of CCR5+ and CXCR3+ leucocytes was found in the adventitia and was co-localized with the expression of CCL5/RANTES mRNA. Interestingly, we found marked expression of DARC on adventitial high endothelial venules in vasculitis lesions of patients with GCA, while in arteries from patients with PMR DARC was only expressed on a low number of vessels with flat lining endothelium.

CONCLUSIONS

The co-localization of infiltrating CCR5+ and CXCR3+ leucocytes together with CCL5/RANTES and DARC in vasculitis lesions suggests a role for these chemokine receptors in leucocyte infiltration, possibly supported by DARC-mediated vascular presentation of chemokines.

Giant cell arteritis and polymyalgia rheumatica: two different but often overlapping conditions

OBJECTIVES

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common and frequently overlapping diseases. In this manuscript similarities and differences between these conditions have been assessed.

METHODS

A retrospective review of the literature was conducted. Reports emphasizing features in common and possible differences are reviewed.

RESULTS

GCA and PMR are characterized by late age at disease onset, are more common in women, exhibit evidence of a systemic inflammatory response, and generally respond well to corticosteroids. In biopsy-proven GCA, PMR manifestations are observed in up to 50% of cases. PMR may be the presenting feature in patients who later develop typical cranial manifestations of GCA. However, PMR manifestations may be observed in diverse conditions other than GCA. Patients with isolated PMR are younger than those with PMR associated to biopsy-proven GCA and exhibit milder inflammatory disease as shown by significantly less abnormality in most laboratory findings. Recent observations have shown that the frequency of pathologic features of GCA in temporal artery biopsies of patients with clinically isolated PMR is less than that previously reported. Besides different steroid requirements, GCA is associated with more vascular complications. Genetic differences, in particular different HLA-DRB1 associations, also have been observed.

CONCLUSIONS

Polymyalgia manifestations may be observed in patients with biopsy-proven GCA, but isolated PMR may be the only clinical feature or the phenotypic expression of a number of conditions. Clinical features and immunogenetic studies show subtle differences between GCA and PMR.

HLA-DRB1 allele distribution in polymyalgia rheumatica and giant cell arteritis: Influence on clinical subgroups and prognosis

OBJECTIVE

To evaluate HLA-DRB1 associations in patients with polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) in the Spanish population, especially those alleles that include the disease-linked sequence motif DRYF (positions 28 to 31 of the HVR2).

METHODS

We performed a PCR based HLA-DRB1 genotyping in 89 PMR patients, 44 GCA patients, and 99 unrelated healthy controls from the same geographic area.

RESULTS

We did not find any significant difference between the whole group of PMR/GCA patients (n = 133) compared with the healthy controls with the exception of a lower frequency of HLA-DRB1*0405 in the patient group (odds ratio [OR], 0.1 [CI0.02 to 1.2]; P =.04). The distribution of DRB1 alleles was very similar between PMR patients and controls. However, DRB1*0401 (OR, 3.1 [1.1 to 8.6]; P =.02) and DRB1*0404 (OR, 3.5 [0.97 to 12.9]; P =.04) were overrepresented in patients with GCA compared with the control group. DRB1*04 (OR, 1.9 [0.96 to 3.8]; P =.06), especially *0401 (OR, 2.8 [1 to 7.7]; P =.04), and DRB1*07 (OR, 2.3 [1.2 to 4.6]; P =.01) were more frequent in GCA than in PMR. Frequency of the DRYF 28-31 motif was similar among GCA (79.5%), PMR (89.9%), and controls (87.9%) and did not confer any significant risk of the development of systemic vasculitis. We also compared the DRB1 allele distribution in patients with classic PMR (n = 58) and those with an erythrocyte sedimentation rate (ESR) <40 mm/hour (n = 31). Patients with classic PMR expressed DRB1*07 less frequently (OR, 0.4 [0.1 to 1]; P =.04) and had a higher frequency of the DRYF 28-31 motif (94.8% vs 80.6%; P =.03) than patients with ESR < 40. Within the GCA group, DRB1 alleles were not predictive for the development of severe ischemic complications. However, the development of relapses in patients with PMR was associated with a higher frequency of DRB1*09 (5.6% vs 0%; P =.04).

CONCLUSIONS

Our data suggest that the HLA-DRB1 alleles associated with susceptibility for developing PMR and GCA are different. Whether PMR with low ESR represents a different clinical subset of the disease should be clarified in a larger sample of patients. HLA-DRB1 genes might predict the presence of relapses in PMR, but they do not seem to be indicators of severe disease in GCA patients.

Are polymyalgia rheumatica and giant cell arteritis the same disease?

OBJECTIVE

To summarize the evidence about the relationship between polymyalgia rheumatica (PMR) and giant cell arteritis (GCA).

METHODS

Review of relevant articles from the English-language literature.

RESULTS

Epidemiologic studies suggest that PMR and GCA are closely related conditions affecting people over 50 years and frequently occurring in the same patient. PMR symptoms have been observed in 40 to 60 percent of GCA clinical series. Also, temporal artery biopsy may yield positive results for GCA in patients with isolated PMR. Conflicting HLA-DRB1 genotype results have been reported, and recent studies have shown that PMR and GCA have different expression of RANTES, TNFalpha microsatellite, and IL-6 promoter genetic polymorphisms. Search for a possible common infectious agent have yielded disappointing results. Although parvovirus B19 DNA is present in the artery wall of patients with GCA, this virus may be only an innocent bystander. Cytokine studies on a limited number of temporal artery biopsy specimens have shown that interferon-gamma is produced in GCA and not in PMR, suggesting that this cytokine may be crucial to the development of overt vasculitis.

CONCLUSIONS

PMR and GCA frequently occur together but no definitive conclusions can be drawn about the nature of this association.

Interferon-gamma gene microsatellite polymorphisms in patients with biopsy-proven giant cell arteritis and isolated polymyalgia rheumatica

OBJECTIVES

Inflammatory cytokines are implicated in the pathogenesis of giant cell arteritis (GCA) and polymyalgia rheumatica (PMR). In this study we have examined the potential association of a CA repeat polymorphism in the first intron of the interferon gamma (IFN-gamma) gene with disease susceptibility and clinical expression of these conditions.

METHODS

Seventy-nine patients with isolated PMR, 59 biopsy-proven GCA patients and 129 ethnically matched controls from Lugo (NW Spain) were studied. Patients and controls were genotyped by molecular methods for the microsatellite dinucleotide (CA) repeat within the first intron of IFN-gamma gene.

RESULTS

No significant differences in the distribution of alleles for the IFN-gamma gene polymorphism between GCA and isolated PMR patients and controls were found. However, the frequency of IFN-gamma allele *4 (128 bp) was reduced in GCA patients (33.1%) compared with isolated PMR patients (46.2%). Also, GCA patients with visual ischemic manifestations exhibited a significantly reduced frequency of IFN-gamma allele *4 compared with those without visual manifestations (17.9% versus 42.5%; p = 0.05 [OR: 0.36, 95% CI: 0.13-1.00]). Moreover, allele *3 (126 bp) was over-represented in the GCA patients with visual ischemic manifestations (71.4% versus 44.4% in the remaining GCA patients; p = 0.01 [OR = 3.13, 95% CI: 1.27-7.68]).

CONCLUSIONS

In GCA, IFN-gamma functional polymorphisms are associated with clinical manifestations of severity rather than susceptibility to this vasculitis.

Genetic markers of disease susceptibility and severity in giant cell arteritis and polymyalgia rheumatica

BACKGROUND AND OBJECTIVES

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common and often overlapping diseases that generally occur in elderly patients. In this article, we examine the role of different genes as markers of disease susceptibility and severity in GCA and PMR.

METHODS

The influence of human leukocyte antigen (HLA)-DRB1 and tumor necrosis factor alleles, as well as the different allelic polymorphisms, on the susceptibility and severity to GCA and PMR was examined. A review of the literature was conducted.

RESULTS

Most studies have described an association of GCA with HLA-DRB1(*)04 alleles. However, HLA-DRB1 association in patients with PMR varies from one population to another. In Northwest Spain, patients with GCA and PMR exhibited different tumor necrosis factor microsatellite polymorphism associations. Studies of intercellular adhesion molecule-1 biallelic polymorphisms have yielded contradictory results. Interleukin 1 cluster and tumor necrosis factor alpha polymorphisms increased susceptibility to GCA and PMR slightly. In Northwest Spain, interleukin 6 promoter polymorphism at position -174 modulated the phenotypic expression of PMR in biopsy-proven GCA. In the same population, regulated upon activation, normal T cell expressed and presumably secreted gene promoter biallelic polymorphism at position -403 was a marker for PMR susceptibility but not for GCA, and corticotropin-releasing hormone polymorphism appeared to be implicated in the risk of severe ischemic complications in patients with GCA.

CONCLUSIONS

The present analysis confirms that GCA and PMR are polygenic diseases. The search for additional genes is necessary to better understand the pathogenesis of these conditions.

Mannose-binding lectin variant alleles and HLA-DR4 alleles are associated with giant cell arteritis

OBJECTIVE

To determine whether variant alleles of the mannose-binding lectin (MBL) gene causing low serum concentrations of MBL and/or polymorphisms of HLA-DRB1 are associated with increased susceptibility to polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) or particular clinical phenotypes of PMR/GCA.

METHODS

MBL and HLA-DRB1 alleles were determined by polymerase chain reaction in 102 Danish patients with PMR (n = 37) or GCA (n = 65). Two hundred fifty and 193 healthy individuals served as controls for MBL and HLA genotyping, respectively.

RESULTS

The prevalence of MBL variant alleles in controls, patients with PMR only, and patients with GCA was 37, 32, and 53% (p = 0.01), respectively. HLA-DRB1*04 was found in 47% of patients with PMR only and in 54% of patients with GCA, which differed significantly from the 35% found in controls (p = 0.01). HLA-DR4 alleles were not associated with any clinical phenotypes of PMR/GCA, whereas MBL variant alleles were associated with cranial arteritis, high erythrocyte sedimentation rate, and low B-hemoglobin.

CONCLUSION

We found MBL variant alleles and HLA-DR4 alleles to be weak susceptibility markers for GCA. In patients with PMR/GCA, MBL variant alleles were associated with signs of increased inflammatory activity and clinical signs of arteritic manifestations. This was not found for HLA-DR4 alleles. These findings indicate that HLA-DR4 and MBL are contributing to the pathophysiology of GCA at different levels in the disease process.

Familial giant cell arteritis and polymyalgia rheumatica: aggregation in 2 families

The ethnic and geographic prevalence, the familial aggregation, and the reported association with some HLA class II antigens of both giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) strongly suggest the role of genetic factors in the pathogenesis of these diseases. We describe the familial aggregation of GCA and PMR in 2 unrelated families from Northern Italy. In the first family, 2 sisters developed GCA a few months apart. In the second, one sister had GCA, and 2 years later her siblings developed PMR nearly simultaneously. Patients with GCA in the first family shared the whole HLA genotype (A*24,*26, B*38,*55, DRB1*11,*14, DQB1*05,*07, DRB3*). In the second family, both PMR siblings carried the A*68, B*44, DRB1*11, DQB1*07, DRB3* alleles. Thus all patients of both families shared DRB1*11, DQB1*07, and DRB3*. Predisposing immunogenetic factors of both GCA and PMR are discussed.

IL-6 promoter polymorphism at position -174 modulates the phenotypic expression of polymyalgia rheumatica in biopsy-proven giant cell arteritis

OBJECTIVES

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are related diseases in which diverse genetic and environmental factors are implicated. Both GCA and PMR are characterized by an intense acute phase reaction. In these sYndromes the increased production of IL-6 has been observed. To investigate further the genetic influence of IL-6 in GCA and PMR we have examined the IL-6 promoter polymorphism (G to C) at position -174 in the 5' region in a series of patients from Northwest Spain diagnosed with GCA and/or PMR.

METHODS

Sixtxy-two biopsy-proven GCA patients (30 of them with associated PMR) and 84 patients with isolated PMR were studied. Patients and ethnically matched controls (n = 124) were from the Lugo region (Galicia, Northwest Spain). Patients and controls were genotyped for HLA-DRB1 and IL-6 polymorphism at position -174 by molecular methods.

RESULTS

IL-6-174 allele C was marginally increased infrequency in GCA patients with PMR manifestations compared with isolated GCA (Pcorr 0.06; OR = 2.3). The increase in the frequency of the CC genotype in GCA patients with PMR versus those with isolated GCA was statistically significant (Pcorr 0.02). The increased frequency of allele C in GCA patients with PMR was more commonly observed in HLA-DRBI *04 negative patients. However, this polymorphism was not associated with a higher risk of ischemic events in GCA or with relapses in PMR.

CONCLUSION

Allele C at position -174 in the 5' promoter region of the IL-6 gene may be associated with PMR in biopsy-proven GCA patients not carrying HLA-DRBI *04 alleles.

Intercellular adhesion molecule-1 gene polymorphisms in isolated polymyalgia rheumatica

OBJECTIVE

In untreated polymyalgia rheumatica (PMR), high levels of circulating soluble intercellular adhesion molecule-1 (ICAM-1) have been observed. To investigate the clinical implication of ICAM-1 polymorphisms in isolated PMR, we examined their potential influence in an unselected series of patients.

METHODS

We studied 72 patients with isolated PMR and 129 ethnically matched controls from Lugo, Spain. Patients and controls were genotyped for HLA-DRB1 and ICAM-1 polymorphism at codons 241 and 469 by molecular methods.

RESULTS

The distribution of alleles and genotypes for each ICAM-1 polymorphism did not show significant differences between patients with isolated PMR and controls. There were also no associations between ICAM-1 polymorphisms and relapses of the disease. The latter was primarily associated with carriage of an HLA-DRB1*0401 allele (OR 7.2, p = 0.01), although all relapsed patients with HLA-DRB1*0401 also carried the GG genotype of the ICAM-1 polymorphism at codon 241. The presence of both HLA-DRB1*0401 and the GG241 ICAM-1 genotype gave an OR of 15.2 (p = 0.005) after correction for age and sex.

CONCLUSION

Although ICAM-1 polymorphisms alone do not appear to be associated with disease severity in isolated PMR, the presence of both HLA-DRB1*0401 and the ICAM-1 codon 241 GG homozygosity was significantly associated with increased risk of relapses in these patients.

Corticotropin releasing hormone promoter polymorphisms in giant cell arteritis and polymyalgia rheumatica

OBJECTIVE

Giant cell (temporal) arteritis (GCA) and polymyalgia rheumatica (PMR) are different but overlapping diseases of unknown etiology affecting the elderly. Corticotropin-releasing hormone (CRH) helps to regulate the immune response and maintain homeostasis during inflammatory stress. CRH promoter region polymorphisms in the 5'regulatory region of the CRH gene have been described. To investigate the possible implications of the CRH promoter polymorphisms in PMR and GCA susceptibility we have examined a series of patients with these conditions.

METHODS

Sixty-two patients with biopsy-proven GCA, 86 patients with isolated PMR and 147 ethnically matched controls from the Lugo region of Northwest Spain were included in this study. Patients and controls were genotyped for CRH polymorphism in the 5' regulatory region of the gene at position 1273 (alleles A1 andA2) and at position 225 (alleles B1 and B2) by PCR-restriction fragment length polymorphism. Allele frequencies and genotype distribution were evaluated by the chi-square test.

RESULTS

When GCA and PMR patients were examined for alleles and genotypes for each CRH polymorphism no significant differences in frequency were found compared with controls. A higher CRH-A2 allele frequency was observed in GCA patients with visual complications (21.4%) compared with controls (9.2%) and GCA cases without eye involvement [6.3%; p= 0.017, Pcorr = 0.034, O.R: 4.1 (95% CI 1.2- 13.9)], although this was based on a small sample of patients with ischemic visual complications (n = 14) and should be interpreted with caution. No differences in CRH allele or genotype frequencies were observed in isolated PMR patients stratified by relapses and recurrence of disease symptoms.

CONCLUSION

Polymorphisms in the CRH gene regulatory region do not appear to be associated with increased susceptibility to PMR or GCA. The CRH-A2 allele may encode risk for the development of visual complications in GCA, although further studies to confirm this will be required.

Familial aggregation of polymyalgia rheumatica and giant cell arteritis: genetic and T cell repertoire analysis

OBJECTIVE

Several reports of familial aggregation of giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) have been described although detailed genetic and immunological studies are scarce. Our aims were to investigate the influence of HLA-DRB1 alleles and to analyze the phenotype and T cell receptor (TCR) usage of circulating T lymphocytes in a familial case of GCA and PMR.

METHODS

HLA-DRB1 typing was carried out using polymerase chain reaction amplification with specific primers. The study of the circulating T cell repertoire was performed by staining with specific monoclonal antibodies and flow cytometry analysis.

RESULTS

Patient 1 developed GCA at the age of 71, four years prior to the diagnosis of PMR in her older brother. The HLA-DRB1 typing of Patient 1 was DRB1*04 (DRB1*0401)/DRB1*12 and in Patient 2 was DRB1*07/DRB1*12. In our patient population, GCA was associated with an increased frequency of HLA-DRB1*04 compared with PMR patients. Regarding T cell phenotype, the brother with active PMR had a higher expression of surface markers indicating activation in both T cell subsets (CD25 and HLA-DR). The sister with GCA showed a pronounced decrease of CD4+/CD45RA+ T cells with respect to her brother with PMR. Both patients carried a significant depletion of CD28 in both subsets, specially within the CD8+ T cell compartment. The BV gene usage differed from one patient to the other. T cell expansions were identified in both patients but the specificities were different.

CONCLUSION

We describe an association of GCA and PMR between two first degree relatives with significant genetic and immunologic differences. Our results suggest that the pathogenic mechanisms leading to the development of GCA and PMR are probably multifactorial, and both genetic and environmental factors may contribute to the development of these diseases.

DRB1 alleles in polymyalgia rheumatica and rheumatoid arthritis in southern France

To investigate the association of HLA-DRB1 alleles with polymyalgia rheumatica (PMR) and rheumatoid arthritis (RA), 55 patients with PMR without giant cell arteritis, 203 patients with RA and 230 controls, all from the European population of Marseille, were HLA-DRB1 genotyped by PCR-SSO. HLA-DRB1*01 was significantly increased in both the PMR and RA groups compared to controls (35% versus 17%, P(c) < 0.05, and 41% versus 17%, P(c) < 0.001, respectively). HLA-DRB1*04 was significantly increased in the RA group compared to controls (48% versus 23%, P(c) < 0.001) but not in the PMR group. HLA-DRB1*04 subtype frequencies were significantly different between PMR patients and RA patients. Shared epitope-positive HLA-DRB1*04 alleles (DRB1*0401, 0404, 0405, 0408) were significantly overrepresented in RA patients compared to PMR patients and shared epitope-negative HLA-DRB1*04 alleles were overrepresented in PMR patients compared to RA patients. In conclusion, in the Mediterranean population studied, HLA-DRB1*01 is associated with RA and PMR whereas HLA-DRB1*04 is associated with RA only.

Seronegative rheumatoid arthritis in elderly and polymyalgia rheumatica have similar patterns of HLA association

OBJECTIVE

To examine whether polymyalgia rheumatica (PMR) and late onset rheumatoid arthritis have identical or similar HLA-DRB1 genetic associations.

METHODS

Seventy five PMR cases without evidence of giant cell arteritis were available for study. One hundred seven RA cases were investigated, of which 62 had disease onset after age 60 years. All cases were compared with 145 ethnically matched controls. All cases and controls originated from Lugo, NW Spain. HLA-DRB1 typing was performed on DNA samples using PCR based molecular methods.

RESULTS

Early onset RA (< or =40 yrs) was strongly associated with DRB1*04 (DRB1*0401 and *0404). In contrast late onset RA (> or = 60 yrs) was not associated with DRB1*04 but was associated with DRB1*01. Stratification of late onset RA cases by rheumatoid factor status revealed that DRB1*01 was only increased in seropositive RA cases. Late onset seronegative RA cases exhibited increased frequency of DRB1*13/*14; this was also observed in PMR cases where coexistence of GCA had been excluded.

CONCLUSION

These data indicate that (1) HLA associations with RA differ with respect to age at disease onset; and (2) seronegative late onset RA and "isolated" PMR have a similar HLA-DRB1 association and may have an identical etiological basis.

Genetic epidemiology. Giant cell arteritis and polymyalgia rheumatica

Giant cell arteritis (GCA) (temporal arteritis) and polymyalgia rheumatica (PMR) are common, frequently related conditions in people generally over 50 years of age. Most studies have shown an association of GCA with HLA-DRB1 *04 alleles. As regards isolated PMR, however, the HLA class II genetic susceptibility varies from one population to another. Besides associations with HLA, tumor necrosis factor appears to influence susceptibility to both conditions. Genetic polymorphisms have also been considered to be important candidates as factors of susceptibility to GCA and PMR. In this regard, gene polymorphisms for ICAM-1 (intercellular adhesion molecule 1), RANTES (regulated upon activation, normal T cell expressed, and presumably secreted), and interleukin (IL)-1 receptor antagonist seem to play a role in the pathogenesis of GCA and PMR in some populations. However, additional studies are required to clarify the genetic influence on susceptibility to these conditions.

Interleukin-1 cluster and tumor necrosis factor-alpha gene polymorphisms in polymyalgia rheumatica

OBJECTIVE

To investigate whether polymorphisms in the interleukin (IL)-1 locus (human chrom. 2q13) and TNF-alpha gene are associated with susceptibility to or severity of polymyalgia rheumatica (PMR).

METHODS

The study included 92 consecutive PMR patients diagnosed over a 5-year period who were prospectively followed-up for at least one year and 79 healthy controls over the age of 50 residing in the same area. All the patients and controls were Caucasians of Italian origin. We tested the allelic distribution of IL-1A (+4845), IL-B (-511), IL-B (+3954), IL-1RN Intron 2 VNTR and TNFA (-308). Frequencies were compared in the patient and control groups.

RESULTS

A statistically significant association between PMR patients and the IL1RN*2 allele in the homozygous state was found [OR 8.46 (95% CI 1.05-68.31)]. The polymorphisms in the other genes of the IL-1 gene cluster did not reveal any association with PMR when compared with controls. A weak association between PMR patients and the TNF2 allele was also present [OR 2.09 (95% CI 1.0-4.17)]. None of the gene variants studied was associated with the disease severity of PMR.

CONCLUSION

Our findings show that IL1RN*2 allele, particularly in the homozygous state, is associated with susceptibility to, but not with the severity of, PMR.

Absence of the association with CC chemokine receptor 5 polymorphism in polymyalgia rheumatica

OBJECTIVE

Elevated RANTES serum levels are present in polymyalgia rheumatica (PMR) patients with active disease. Chemokines may contribute to the inflammatory PMR process through their binding to CC chemokine receptor 5 (CCR5). The aim of this study was to examine if the 32 base pair deletion allele in CCR5 (CCR5 delta 32 allele) might be associated with PMR susceptibility and influence the disease outcome.

METHODS

We enrolled 88 consecutive patients with PMR residing in the Reggio Emilia area (Italy) who had a follow-up duration of at least one year. As a control group we used 86 healthy blood donors from the same geographic area. The CCR5 genotype of all PMR patients and controls was studied by polymerase chain reaction amplification of the region which includes the 32 deletion (CCR5 delta 32). RANTES serum levels were measured by commercial ELISA kits in CCR5 delta 32 heterozygous and CCR5 homozygous PMR patients at diagnosis before starting corticosteroid therapy and again after 6 months of therapy, as well as in 28 healthy subjects over 50 years of age.

RESULTS

Frequencies of the CCR5 and CCR5 delta 32 alleles in patients and controls did not differ significantly. Homozygosity for CCR5 delta 32 was not detected in PMR patients and was detected in only one of the controls. No significant differences were observed between the patients carrying the CCR5 delta 32 allele and those homozygous for the normal CCR5 allele when we compared sex, presence of distal synovitis and systemic signs and/or symptoms, initial and cumulative prednisone dose, duration of therapy, ESR at diagnosis, frequency of relapse/recurrence and RANTES serum levels at diagnosis and after 6 months of corticosteroids.

CONCLUSION

These results indicate that the frequency of the 32 deletion of the CCR5 receptor was not significantly different between PMR patients and healthy controls, and this genotype does not appear to be associated with the susceptibility to or severity of PMR.

Association of giant cell arteritis and polymyalgia rheumatica with different tumor necrosis factor microsatellite polymorphisms

OBJECTIVE

To determine whether giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are associated with different tumor necrosis factor (TNF) microsatellite polymorphisms.

METHODS

Typing of TNF microsatellite polymorphisms was carried out by molecular-based techniques on DNA obtained from a population sample of residents from Lugo, northwestern Spain. A case-control approach was used to compare 136 patients with GCA and/or PMR with 147 ethnically matched controls. The association of disease with TNF microsatellite polymorphisms was investigated using chi-square tests and multivariate logistic regression analyses.

RESULTS

Different TNF microsatellite associations were found with GCA and PMR. In patients with isolated GCA, the primary association was with TNFa2, which was independent of the GCA associations with HLA-DRB1*0401 and *0101. A negative association was found with TNFa10. In patients with isolated PMR, there was a positive association with TNFb3. This was found to be independent of the HLA-DRB1*13/*14 association in isolated PMR. TNFd4 was negatively associated with isolated PMR. Forward stepwise logistic regression analyses indicated that the strongest association with GCA was provided by the TNFa2 allele, although DRB1*0401 and *0101 were still associated. PMR was primarily associated with TNFb3. A direct comparison of TNF allele frequencies between isolated GCA and isolated PMR indicated that the main difference between these conditions occurred in the frequency of TNFa10.

CONCLUSION

GCA and PMR in individuals from northwestern Spain are associated with different TNF microsatellite polymorphisms. The primary TNF associations (TNFa2 and TNFb3) appear to influence susceptibility to these conditions independent of any HLA-DRB1 association.

RANTES gene polymorphism in polymyalgia rheumatica, giant cell arteritis and rheumatoid arthritis

OBJECTIVE

To investigate whether a biallelic polymorphism (A or G) occurring within the promoter region of the RANTES gene (position-403) is associated with polymyalgia rheumatica (PMR), giant cell arteritis (GCA) and rheumatoid arthritis (RA).

METHODS

A PCR-RFLP method was used to genotype cases and controls for this polymorphism. 3 groups of patients were examined; these comprised GCA patients who did not exhibit features of PMR (n = 30), PMR patients who did not exhibit features of GCA (n = 53) and RA patients (n = 99). All patients and controls (n = 65) originated from the area surrounding Lugo, Galicia, NW Spain.

RESULTS

A significant increase in the frequency of allele A was found in PMR patients compared with normal controls. A marginal increase of this allele frequency was observed in RA but not in GCA patients.

CONCLUSION

This is the first report of an association of a RANTES gene polymorphisms with PMR and RA. Our data suggest a possible role for of RANTES in the development of both PMR and RA.

Intercellular adhesion molecule 1 gene polymorphisms in polymyalgia rheumatica/giant cell arteritis: association with disease risk and severity

OBJECTIVE

Intercellular adhesion molecule 1 (ICAM-1) is widely distributed in shoulder synovial membrane of active polymyalgia rheumatica (PMR) and strongly expressed in granulomatous inflammatory infiltrate of the temporal artery in giant cell arteritis (GCA). ICAM-1 genes may contribute to the inflammatory PMR/GCA processes. We examined potential associations of ICAM-1 gene polymorphisms with PMR/GCA susceptibility and severity.

METHODS

We enrolled 121 consecutive patients with "pure" PMR and 56 patients with biopsy positive GCA residing in Reggio Emilia, Italy. Among patients with PMR, 91 had a followup duration of at least one year. Selected as control subjects were 228 healthy blood donors, 75 patients with nonarteritic central retinal artery occlusion, and 116 cataract surgery patients from the same geographic area. All PMR/GCA patients and controls were genotyped by polymerase chain reaction and allele-specific oligonucleotide techniques for ICAM-1 polymorphism at codon 241 (exon 4) and codon 469 (exon 6).

RESULTS

The frequency of R241 was significantly higher in PMR/GCA patients [p = 0.00001, odds ratio (OR) 5.0 (95% confidence intervals, CI 2.6-9.6) ], in pure PMR patients [p = 0.00001, OR 5.0 (95% CI 2.5-10.0)], and in GCA patients [p = 0.00005; OR 5.0 (95% CI 2.2-11.5)] compared to the healthy controls. The frequency of R241 was significantly higher in total PMR/GCA patients compared to patients with nonarteritic central retinal artery occlusion [p = 0.0007; OR 5.3 (95% CI 1.8-15.5)] and cataract surgery patients [p = 0.0003; OR 4.1 (95% CI 1.8-9.0)]. The distribution of E/K 469 genotype was similar in PMR/GCA patients and in the 3 control groups. Cox proportional hazards modeling identified 2 variables that independently increased the risk of PMR relapse/recurrence: erythrocyte sedimentation rate at diagnosis > 72 mm/h [relative risk 1.6 (95% CI 1.1-2.3)] and the presence of R241 allele [relative risk 1.6 (95% CI 1.1-2.4)].

CONCLUSION

Our findings show that G/R 241 polymorphism of ICAM-1 is associated with PMR/GCA susceptibility and confers an increased risk of relapse/recurrence in PMR.

Absence of mitochondrial dysfunction in polymyalgia rheumatica. Evidence based on a simultaneous molecular and biochemical approach

OBJECTIVE

To investigate the molecular and biochemical profile of skeletal muscle mitochondria of patients with isolated polymyalgia rheumatica (PMR).

PATIENTS AND METHODS

We included patients with a recent diagnosis of PMR and as control healthy individuals submitted to orthopedic surgery. Skeletal muscle was obtained from quadriceps, thus was mitochondria immediately isolated. Long polymerase chain reaction and Southern blot transference were performed to detect deleted mtDNA molecules. Mitochondrial oxidative activity using different substrates and individual enzyme activity of respiratory chain complexes were assessed to search for any biochemical dysfunction.

RESULTS

Fifty-one individuals (PMR=25, controls=26) were included. Mean age was 72 (11) years; 45% were females. We found no significant increase of deleted mtDNA molecules in PMR patients compared to controls. Both groups differed neither on oxygen consumption (p=NS for all substrates) nor enzymatic activity (p=NS for all complexes).

CONCLUSIONS

Skeletal muscle mitochondria are molecularly and biochemically unaffected in PMR.

The spectrum of polymyalgia rheumatica in northwestern Spain: incidence and analysis of variables associated with relapse in a 10 year study

OBJECTIVE

To examine patients presenting with polymyalgia rheumatica (PMR) during a 10 year period in Northwestern Spain and to assess disease incidence and the frequency of relapses in patients diagnosed as having either isolated ("pure") PMR or PMR associated with giant cell arteritis (GCA).

METHODS

Clinical records of patients with PMR diagnosed at the Hospital Xeral Lugo from January 1987 through December 1996 were reviewed. Patients with PMR were categorized into 2 subgroups depending on the presence or absence of associated GCA. Other conditions presenting with polymyalgia symptoms or mimicking isolated PMR were excluded. These patients were followed from the time of diagnosis until either patient's death or January 1, 1998.

RESULTS

One hundred eighty-five patients were studied. The average annual incidence rates of the total group of PMR and isolated PMR were 18.67 x 10(-5) and 13.52 x 10(-5), respectively, in a population aged 50 years or older. Relapses were frequent in both isolated PMR and PMR associated with GCA. In general, they occurred when the dose of prednisone was < 7.5 mg/day or it had been discontinued. Rate of steroid tapering was significantly higher in patients with isolated PMR who had relapses. Patients with HLA-DRB1*0401 had a higher frequency of relapses. As reported in patients with PMR associated with GCA, the adjusted mortality rate in patients with isolated PMR showed no difference compared to the Spanish population aged 50 years or older.

CONCLUSION

In Northwestern Spain, PMR is a nonfatal disease with a low incidence and frequent relapses. A possible influence of HLA-DRB1*04 alleles in the development of more severe disease, with greater tendency to relapses, is suggested.

HLA-DRB1 alleles associated with polymyalgia rheumatica in northern Italy: correlation with disease severity

OBJECTIVE

To examine the association of HLA-DRB1 alleles with polymyalgia rheumatica (PMR) in a Mediterranean country and to explore the role of HLA-DRB1 genes in determining disease severity.

METHODS

A five year prospective follow up study of 92 consecutive PMR patients diagnosed by the secondary referral centre of rheumatology of Reggio Emilia, Italy was conducted. HLA-DRB1 alleles were determined in the 92 patients, in 29 DR4 positive rheumatoid arthritis (RA) patients, and in 148 controls from the same geographical area by polymerase chain reaction amplification and oligonucleotide hybridisation.

RESULTS

No significant differences were observed in the frequencies of HLA-DRB1 types and in the expression of HLA-DRB 70-74 shared motif between PMR and controls. The frequency of the patients with double dose of epitope was low and not significantly different in PMR and in controls. No significant differences in the distribution of HLA-DR4 subtypes were observed between DR4+ PMR, DR+ RA, and DR4+ controls. Results of the univariate analysis indicated that an erythrocyte sedimentation rate (ESR) at diagnosis > 72 mm 1st h, the presence of HLA-DR1, DR10, rheumatoid epitope, and the type of rheumatoid epitope were significant risk factors associated with relapse/recurrence. Cox proportional hazards modelling identified two variables that independently increased the risk of relapse/recurrence: ESR at diagnosis > 72 mm 1st h (RR=1.5) and type 2 (encoded by a non-DR4 allele) rheumatoid epitope (RR=2.7).

CONCLUSION

These data from a Mediterranean country showed no association of rheumatoid epitope with PMR in northern Italian patients. A high ESR at diagnosis and the presence of rheumatoid epitope encoded by a non-DR4 allele are independent valuable markers of disease severity.

[Nosology and epidemiology of Horton's disease and polymyalgia rheumatica]

Giant cell arteritis is the most frequent of all vasculitides. Estimates of its incidence lies between 10 and 20 cases/100,000/year, and estimates of its prevalence in the population over 50 between 100 and 200/100,000/year. Giant cell arteritis affects primarily patients over 50, and the increased prevalence among women, partially reflects the sex distribution in this age group. The cause of the disease remains unknown, but a genetic predisposition (HLA-DR 4 group), has been clearly shown. Seasonal, and annual peaks of incidence have been shown in some studies, suggesting an infectious or environmental etiologic factor.

Distribution of HLA-DRB1 alleles of patients with polymyalgia rheumatica and giant cell arteritis in a Mediterranean population

OBJECTIVE

To evaluate HLA-DRB1 associations in polymyalgia rheumatica (PMR) and giant cell arteritis (GCA) compared to rheumatoid arthritis (RA).

METHODS

One hundred twenty-one patients were included and oligotyped: 79 with PMR alone and 42 with GCA (14 also had PMR). We also genotyped 1609 healthy controls and 433 patients with RA. Statistical analysis included Fisher's exact test and calculation of the odds ratio (95% CI).

RESULTS

Compared to controls, the DRB1*04 phenotype was increased in PMR (39.2%; OR = 2.4, p = 0.0005) and GCA (45.2%; OR = 3.1, p = 0.0005). This association was weaker than in RA (p = 0.01). DRB1*07 was more frequent in GCA (31.0%) than in PMR (13.4%; p = 0.03), but the difference was not significant in comparison to controls. The distribution of DRB1*04 subtypes was similar in PMR and GCA, but different from RA and controls. However, the frequency of 0402 and 0403 subtypes could not be distinguished from that in patients with RA. Double occurrence of RA associated alleles was less frequent in PMR and GCA (9.9%; p = 0.005) than in patients with RA (20.8%). There was no significant relationship between markers of disease activity/severity and HLA-DRB1 genes in PMR or GCA.

CONCLUSION

PMR and GCA were associated with HLA-DRB1*04, but more weakly than RA. Nevertheless, these data suggest that HLA-DRB1* genes are closely related to susceptibility in PMR, GCA, and RA and do not support the hypothesis of a different linkage to the 3rd hypervariable region of DRB1 alleles. By contrast with RA, HLA-DRB1* genes do not appear to be indicators of disease severity in PMR and GCA.

Molecular analysis of HLA-DR polymorphism in polymyalgia rheumatica. Swiss Group for Research on HLA in Polymyalgia Rheumatica

OBJECTIVE

To analyze by molecular typing possible associations of HLA-DRB1 alleles with polymyalgia rheumatica (PMR) compared to controls and patients with rheumatoid arthritis (RA) in Switzerland.

METHODS

In a multicenter survey, we recruited 100 patients with PMR with and without signs of giant cell arteritis (GCA), 198 with RA, and 200 controls (volunteer bone marrow donors). HLA-DR generic typing was performed by microtiter plate oligotyping and DR4 subtypes analyzed by dot blot hybridization with sequence specific oligonucleotides or by polymerase chain reaction sequence specific primers.

RESULTS

DR4 and DR1 tended to be increased in PMR, compared to controls (36 vs 30%, p = 0.30; and 19 vs 12%, p = 0.16, respectively). Frequencies of all RA associated DR4 and DR1 subtypes tended to be increased in PMR as well. Frequency of the HLA-DR beta 1 70-74 shared motif (QK/RRAA) was significantly higher in PMR than in controls [50 vs 36%, odds ratio (OR) = 1.8, p = 0.018], although lower than in RA (77 vs 36%, OR = 6.0, p < 0.0001), and slightly out of the range of significance if a Bonferroni correction was applied (p = 0.1). At double dose, this epitope was also increased in PMR, but not significantly (5 vs 2%, OR = 2.6, p = 0.17), while it was markedly augmented in RA (22 vs 2%, OR = 14, p = < 0.0001). In patients with the shared epitope, the frequency of clinical signs of GCA tended to be increased (19 vs 10%, p = 0.25). Frequency of the HLA-DR beta 1 DRYF 28-31 motif was identical in PMR (95%) and controls (93%).

CONCLUSION

PMR may be associated with the HLA-DR beta 1 70-74 shared epitope. This association, however, would be much weaker for PMR than for RA, particularly with the shared epitope at double dose. PMR is clearly not associated with the HLA-DR beta 1 DRYF 28-31 motif.

Detection of clonally rearranged T-cell-receptor gamma chain genes from T-cell malignancies and acute inflammatory rheumatic disease using PCR amplification, PAGE, and automated analysis

Clonal expansions of T cells carrying identical T-cell-receptor (TCR) genes are the hallmark of T-cell malignancies, but they can also result from a strong immune reaction to a dominant epitope. The basis for the molecular detection of clonal T cells is amplification of the V-(D)-N-J region of the TCR gene. We evaluated PCR amplification of the rearranged gamma TCR from genomic DNA extracted from peripheral blood and subsequent polyacrylamide gel electrophoresis (PAGE) in an automated DNA sequencer. We determined the sensitivity for the detection of clonal T cells and propose a standardized evaluation procedure for the electrophoretic profiles generated by the DNA sequencer. The sensitivity of our method was 0.6-1.25% of clonal T cells within a polyclonal background. Sixteen patients with T-cell malignancies, ten with acute inflammatory rheumatic diseases, and twelve healthy controls were examined. Among the systemic T-cell malignancies, all but one patient with T-PLL (8/ 9) revealed a clonal PCR signal. No clonal signal was detectable in any patient in clinical complete remission (5/5) or in either of the two patients with lymphomas limited to cutaneous sites. However, clonal T cells were detected in one patient with polymyalgia rheumatica and in one with reactive arthritis. A polyclonal signal was found in the remaining eight patients with acute inflammatory rheumatic diseases and in 12 healthy controls. Taking our results together, the PCR/PAGE assay is able to reliably distinguish clonal from polyclonal T-cell populations. However, although the sensitivity is limited to approximately 1%, clonal T cells can be found in the peripheral blood of some patients with autoimmune diseases and not only in T-cell malignancies.

HLA antigens in polymyalgia rheumatica in northern Sweden

The HLA-A, B and DR antigens were analyzed with serological methods in 75 patients with polymyalgia rheumatica (PMR). In PMR patients the frequency of the HLA-DR4 antigen was significantly higher (62.1%) compared to blood donors (40%), p < 0.05, but did not differ from patients with seropositive rheumatoid arthritis (RA) from the same area (63.1%). In contrast, the frequency of HLA-B27 in the PMR patients (9.3%) was significantly lower compared to RA (27.2%), p < 0.01, but did not differ from blood donors (16.9%). There was no association between DR4 and disease affliction or severity in PMR. The increased frequency of HLA-B27 in RA but not in PMR in the population of northern Sweden suggests an immunogenetic difference between these two HLA-DR4 associated diseases.

Accumulation of deletions in MtDNA during tissue aging: analysis by long PCR

Multiple deletions of mtDNA have not only been implicated in aging, but also in a wide variety of pathological conditions. The enzyme system used in long-PCR makes it possible to synthesize the entire mitochondrial genome (16.5 kb), exposing the multiple deletions in mtDNAs implicated in and, at least partially, responsible for these pathologies. But it is not the number or type of anomalous mtDNA that is crucial, rather it is their frequency relative to the number of intact copies of the mitochondrial genome. Our work exposes the necessity of quantitating the number of normal mitochondrial DNAs. The accuracy of the technique and the small sample size required permit one to detect multiple deletions, located in a specific organ, and simultaneously measure the fraction of intact molecules. This fraction can then be correlated with mitochondrial dysfunction to serve both as an indicator of tissue aging and a monitor of an impending myopathy.