Diagnosis and management of giant cell arteritis: an Asia-Pacific perspective.

Giant cell arteritis is the commonest primary vasculitis of the elderly. However, the prevalence does vary widely between populations with highest incidence amongst Northern Europeans and lowest amongst East Asians. Preliminary studies suggest that clinical manifestations may differ between different populations. Newer diagnostic approaches including ultrasound, MR angiography and PET imaging are under review. While there have been recent advances in the diagnosis of GCA particularly with regard to imaging, there is an urgent need for improvements in methods of diagnosis, treatment and requirement for screening. Glucocorticoid treatment remain the backbone of therapy. However, glucocorticoid therapy is associated with significant adverse effects. Conventional and novel immunosuppressive agents have only demonstrated modest effects in a subgroup of steroid refractory GCA due to the different arms of the immune system at play. However, recently a study of IL-6 blockade demonstrated benefit in GCA. Newer approaches such as fast-track pathways can also result in improvements in consequences of GCA including blindness.

Giant cell arteritis in patients of Indian Subcontinental descent in the UK.

BACKGROUND: GCA in the Indian Subcontinent (ISC) is rare. Our centre in London, UK, serves an ethnically diverse population, including a significant population of patients of ISC descent. We hypothesise that patients of ISC descent are no less likely than others to present with symptoms suggestive of GCA and therefore to undergo temporal artery biopsy (TAB). METHOD: A retrospective audit of all TABs performed at our institution over an 8 year period, to identify ethnicity (white, black, ISC, other, unknown) and biopsy result. We compared the proportion of all patients of ISC descent attending the ED to the proportion of ISC patients undergoing TAB. We compared the proportion of positive TABs among ISC patients with positive TABs among white patients. We also compared the proportion of TAB in ISC patients with all non-ISC ethnicities combined. RESULTS: The proportion of patients undergoing TAB who were of ISC descent (16.3% of 92) was comparable to the proportion of A&E attendances made up by ISC patients [p = 0.1339]. 3.8% (1/26) of positive biopsies were among patients of ISC descent. White patients were significantly more likely to have a positive biopsy than patients of ISC ethnicity (33% of 61 white patients vs. 7% of 15 ISC [p = 0.0456]), as were patients of non-ISC ethnicity (32.5% of 77 non-ISC patients vs. 7% of 15 ISC patients [p = 0.0464]). DISCUSSION: At our centre, biopsy proven GCA occurs in patients of ISC descent, but rarely. Full investigation for GCA continues to be appropriate where it is suspected, regardless of ethnicity.

Association between the functional PTPN22 G788A (R263Q) polymorphism and susceptibility to autoimmune diseases: A meta-analysis.

This study explored whether the functional protein tyrosine phosphatase nonreceptor 22 (PTPN22) G788A (R263Q) polymorphism is associated with susceptibility to autoimmune diseases. A meta-analysis was conducted using 23 comparative studies with a total of 16,719 patients and 17,783 controls. The meta-analysis showed an association between the A allele of the PTPN22 G788A polymorphism and decreased risk of autoimmune diseases in all subjects (p < 0.001). Analysis after stratification by ethnicity indicated that the PTPN22 788A allele was significantly associated with autoimmune diseases in Europeans (p < 0.001) but not in Latin Americans. Meta-analysis by autoimmune disease type showed a significant negative association between the PTPN22 788A allele and systemic lupus erythematous (SLE) (p = 001), rheumatoid arthritis (RA) (p = 0.008), ulcerative colitis (UC) (p = 0.016), but not Crohn's disease (CD). A single study for each showed no association between the PTPN22 788A allele and systemic sclerosis, giant cell arteritis, Henoch-schonlein purpura, uveitis, and Grave's disease. This meta-analysis demonstrates that the PTPN22 G788A polymorphism confers protection against SLE, RA, and UC, supporting evidence of association of the PTPN22 gene with a subgroup of autoimmune diseases.

Giant cell arteritis in Mexican patients.

BACKGROUND: Giant cell arteritis (GCA) is the most common primary systemic vasculitis worldwide, although it seems to be very rare in some areas, such as Latin America. OBJECTIVES: The objective of the study was to describe the clinical, laboratory, and treatment features in a Mexican Mestizo population with GCA. METHODS: Retrospective data chart review (1989-2010). RESULTS: Twenty-two patients with GCA were identified, 18 women and 4 men. Mean age was 73 (SD, 7.9) years. Diagnosis was made at a mean of 67 (SD, 83.6) days from symptom onset. Most frequent presenting symptoms included headache (90%), constitutional symptoms (86%), and polymyalgia rheumatica (59%). Severe cranial ischemic complications were present in 32%. Amaurosis fugax and blindness were present in 36% and 27%, respectively. High erythrocyte sedimentation rate was present in 89% of patients. Rapid response to prednisone treatment was seen, but in 10 patients, relapse occurred, possibly related to fast tapering. Additional treatment was methotrexate (n = 8), azathioprine (n = 5), and cyclophosphamide (n = 3). Median follow-up was 242 (SD, 214) weeks. CONCLUSIONS: Giant cell arteritis is rarely recognized in Latin America. We report on characteristics of GCA in a population of Mexican Mestizos, as ours is the largest series to be reported from Latin America so far. When compared with other series, age at onset is similar, females are more affected, and although a good response to corticosteroid treatment was seen, a higher frequency of amaurosis fugax and blindness was observed, accounting for an unfavorable functional outcome in 6 (27%) of 22 patients.

Giant cell arteritis: clinical features of patients visiting a headache clinic in Japan.

OBJECTIVE: The first symptom of giant cell arteritis (GCA) is usually a headache. Japan has a low prevalence of GCA, and clinical features of this disorder have not been fully investigated. We conducted a retrospective evaluation of clinical features in patients with giant cell arteritis who visited a headache clinic in Japan. METHODS: Clinical and demographic data were obtained from clinical examinations, face-to-face interviews, and hospital records. PATIENTS: Subjects comprised 19 patients (9 men, 10 women). RESULTS: Mean age at disease onset was 78.1 ± 4.8 years (range, 71-86 years). Seventeen of 19 patients (89.5%) had consulted other medical institutions before consulting our hospital, but only 2 of those patients had been diagnosed with GCA at these medical institutions. Manifestations at disease onset included headache (89.5%), ear pain (5.3%), and jaw pain (5.3%). Ocular manifestations were reported in 2 patients (10.5%). No loss of vision occurred. One patient showed trigeminal nerve palsy involving the third division of the nerve. Jaw claudication was observed in 3 patients (15.8%). Concomitant polymyalgia rheumatica was seen in 3 patients (15.8%). No patient showed upper respiratory tract symptoms, arm claudication, or aortic aneurysms. CONCLUSION: Although most patients had consulted other medical institutions before consulting our hospital, they were not diagnosed with GCA at these institutions. Infrequent clinical findings of GCA and lack of symptoms other than headache may contribute to the high rate of unrecognized and misdiagnosed cases of GCA.

The epidemiology of giant cell arteritis in Otago, New Zealand: a 9-year analysis.

AIMS: To study the epidemiology of biopsy proven giant cell arteritis (GCA) in patients in the Otago region, New Zealand. MATERIALS AND METHODS: Records of 363 consecutive patients who underwent temporal artery biopsy at Dunedin Hospital between 1996­2005 were reviewed. Annual incidence of biopsy-proven GCA was estimated, epidemiologic characteristics of the biopsy-positive group was compared with the biopsy-negative group. RESULTS: Among the 363 patients who underwent temporal artery biopsy there were 105 (29%) males and 258 (71%) females; biopsy-proven GCA was diagnosed in 70 (19%) patients. The mean age of biopsy-positive group was 72.8 years (range 57-91 years, SD 8.2), which was comparable to the biopsy-negative group 73.4 years (range 50­97 years, SD 9.5), p<0.2. The mean annual incidence of GCA in Otago was 12.73/100,000 CI (11.7­14.3, p<0.5) for patients ≥50 years over the 9 years of observation. CONCLUSIONS: The first large study of GCA from Australasia demonstrated that a variation in the annual incidence rate for giant cell arteritis in Otago, New Zealand showed a cyclic pattern. The overall incidence seems to reflect the ethnic origins of the majority of the population from Britain.

Giant cell arteritis in Asians: a comparative study.

BACKGROUND: Giant cell arteritis (GCA) is a common systemic vasculitis, with a presumed Caucasian predominance. The occurrence of GCA in Asians has rarely been addressed. This study aims to assess the incidence of giant cell arteritis in Asians. METHODS: In this retrospective review, the self-reported ethnicities of patients with biopsy-proven GCA at the University of California-San Francisco (UCSF) were recorded. Ethnic distribution of the patient population served by UCSF was estimated from an age- and sex-matched control group. The odds ratio for each ethnicity (Asian and Caucasian) was determined and compared using Fisher's exact test and logistic regression analysis. RESULTS: The ethnic distribution of the 38 patients with positive temporal artery biopsies were as follows: Caucasian n=31 (81.6%), Asian n=1 (2.6%) and other n=6 (15.8%). The ethnic distribution of the patient population served by UCSF was as follows: Caucasian 42%, Asian 28% and other 30%. The difference in the proportion of GCA in Asians and Caucasians was statistically significant (OR 0.049 (95% CI 0.0065 to 0.374), p=0.0036). CONCLUSIONS: In our patient population, GCA was seen 20 times less frequently in Asian than Caucasian patients. Although this difference is significantly different (p=0.036), given the small sample size and wide CI this should be viewed as a rough estimate.

Giant cell arteritis in Alaska Natives.

OBJECTIVE: To investigate the incidence of biopsy-proven giant cell arteritis in the Native population of Alaska. DESIGN: Retrospective review of medical diagnostic and Current Procedural Terminology (CPT) codes. PARTICIPANTS: 110,000 Alaska Native patients. METHODS: We conducted a retrospective review of medical diagnostic codes for temporal arteritis, giant cell arteritis, and anterior ischemic optic neuropathy in the medical records of 110,000 Alaska Native patients seen between 1983 and 2003. We examined this same database in search of the CPT code for the temporal artery biopsy procedure. We also re-examined all temporal artery biopsy specimens that had been reported as positive. RESULTS: We identified 122 patients whose diagnostic codes matched those of giant cell arteritis, temporal arteritis, or anterior ischemic optic neuropathy. We found that of 20 temporal artery biopsies that had been performed on this group, only 4 were reported to have had positive results. On re-examination of pathologic specimens, 1 of the 4 was found not to meet the latest pathologic criteria for this disease, leaving only 3 cases of biopsy-proven giant cell arteritis. The calculated incidence of giant cell arteritis in the Alaska Native population is approximately 1/100,000 in those over 50 years old. CONCLUSIONS: Compared with previous epidemiologic studies performed worldwide, our review suggests a very low incidence of biopsy-proven giant cell arteritis among Alaska Natives.

C-reactive protein gene polymorphisms in biopsy-proven giant cell arteritis from Northwestern Spain.

OBJECTIVE: To investigate the potential implication of several polymorphisms of the C-reactive protein (CRP) gene in the predisposition to or clinical expression of giant cell arteritis (GCA). METHODS: A total of 125 patients diagnosed with biopsy-proven GCA and 234 ethnically matched controls from the Lugo region of Northwestern Spain were included in our study. Four functional gene polymorphisms for CRP rs1417938, rs1800947, rs1205, and rs3093059 variants were assessed using a polymerase chain reaction system with predeveloped TaqMan allelic discrimination assay. RESULTS: Although we observed a significant increase in the frequency of heterozygotes for rs1417938 A/T [odds ratio (OR) = 1.70; 95% confidence interval (CI) 1.04-2.80; p = 0.03] and rs1205 C/T (OR 1.73; 95% CI 1.07-2.78; p = 0.02) in patients with GCA, no statistically significant differences in the allelic frequencies of these 2 polymorphisms were found between patients with GCA and controls. A marginal significant increase in the frequency of rs3093059 allele T in patients with GCA compared to controls was observed (OR 1.81; 95% CI 0.97-3.39; p = 0.04). However, the increased frequency of patients with GCA homozygous for rs3093059 T/T in patients with GCA compared to controls was out of the range of significance (OR 1.77; 95% CI 0.92-3.40; p = 0.07). No significant differences were found when we stratified patients with GCA according to the presence of polymyalgia rheumatica or severe ischemic complications of the disease. CONCLUSION: The functional CRP gene polymorphisms assessed in our study do not seem to play a major role in the pathogenesis of GCA in individuals from Northwestern Spain.

Association of CD24 gene polymorphisms with susceptibility to biopsy-proven giant cell arteritis.

OBJECTIVE: To investigate the possible implication of CD24 gene in the genetic predisposition to giant cell arteritis (GCA). METHODS: A total of 120 patients diagnosed with biopsy-proven GCA and 195 ethnically matched controls from the same region were studied. Two putative functional polymorphisms, a C to T coding polymorphism (rs8734) and a TG deletion in the 3' untranslated region (rs3838646) were used as CD24 genetic markers and genotyped using a Taqman 5' allelic discrimination assay. RESULTS: The 2 genetic variants showed statistically significant differences between patients with GCA and controls. The strongest association was observed for the rs3838646 TG/del polymorphism, conferring on the "del" allele an increased risk of GCA genetic susceptibility (odds ratio 1.94, 95% confidence interval 1.15-3.27, p = 0.01). In addition, genotypes carrying the rs3838646 "del" allele showed an increased frequency among GCA patients compared to controls (OR 2.31, 95% CI 1.30-4.1, p = 0.003). For the rs8743, an increased frequency of Val/Val homozygous individuals in patients with GCA compared to controls (OR 6.08, 95% CI 1.50-24.63, p = 0.001) was observed. A high degree of linkage disequilibrium was estimated between the 2 polymorphisms (D' = 0.7) and the C/del haplotype was associated with an increased risk of GCA susceptibility (OR 2.10, 95% CI 1.23-3.60, p = 0.005), whereas the C/TG haplotype showed a protective effect (OR 0.63, 95% CI 0.45-0.87, p = 0.005). CONCLUSION: Our results suggest a potential role for the CD24 gene in the susceptibility to GCA in our population.

Giant cell arteritis in a neuro-ophthalmology clinic in Saskatoon, 1998-2003.

BACKGROUND: We present a retrospective review of all biopsy-positive cases of giant cell arteritis (GCA) presenting to a neuro-ophthalmology practice in Saskatoon, Saskatchewan. METHODS: Records of 141 consecutive patients who underwent temporal artery biopsy at the Saskatoon Eye Centre from July 1998 through June 2003 were reviewed. Patients that were biopsy-positive for GCA were studied and an estimated regional incidence was calculated. Study variables included age at diagnosis, sex, ethnicity, erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) level. RESULTS: Of 141 patients, 37 (26%) had a positive biopsy result for GCA; 11 underwent a second biopsy for a total of 152 biopsies. The average age of the biopsy-positive patients was 76.5 (SD 8.2) years, and the female-to-male ratio was 2.4:l. There were 35 patients (95%) of European descent and 2 patients (5%) of Aboriginal descent. Twenty-three patients had both ESR and CRP testing done before starting steroids. The ESR was elevated in 19 (83%) and the CRP in 22 (96%). The estimated incidence of GCA for Saskatoon and area was 9.4 per 100,000 for people over the age of 50 years. INTERPRETATION: GCA occurs primarily in people of European descent; however, it can affect North American people of Aboriginal descent. Sensitivity for the detection of GCA is higher in CRP than in ESR. The estimated incidence of GCA in Saskatoon and surrounding referral area is moderate compared with other northern areas.

Epidemiology of giant-cell arteritis in an Arab population: a 22-year study.

OBJECTIVE: To study the epidemiology of biopsy-proven giant-cell arteritis (GCA) in an Arab population with clinical features suggestive of GCA. METHODS: Clinical records of 102 patients who underwent temporal artery biopsy (TAB) at King Khaled Eye Specialist Hospital, Riyadh, Saudi Arabia from January 1983 to December 2004 were reviewed. RESULTS: Among the 56 men and 46 women who had TAB, 7 (6.8%) had biopsy-proven GCA. The mean (SD) age of the biopsy-positive group (71.7 (8.6) years) was higher than in the biopsy-negative group (65 (9.8) years; p = 0.005). None of the untreated patients with a negative TAB developed additional symptoms that are typical of GCA. CONCLUSION: The small absolute number of biopsy-proven cases of GCA implies a relatively low incidence of GCA in Arab population, confirming previous observations that GCA occurs primarily in the Caucasian population.