The American College of Rheumatology 1990 criteria for the classification of giant cell arteritis

Platelet factor 4 and beta-thromboglobulin in inflammatory bowel disease and giant cell arteritis

BACKGROUND

As platelet factors are important in the inflammatory response, we examined the course of platelet factor 4 and beta-thromboglobulin in relation to disease activity in inflammatory bowel disease and in giant cell arteritis.

PATIENTS AND METHODS

In a prospective study, the platelet count, platelet factor 4 and beta-thromboglobulin were measured in 20 patients with Crohn's disease, 18 with ulcerative colitis and 19 with giant cell arteritis, during active and inactive disease, as well as in 51 controls without inflammation.

RESULTS

Platelet counts were significantly higher in active vs. inactive Crohn's disease, ulcerative colitis and giant cell arteritis. Levels of platelet factor 4 and beta-thromboglobulin were significantly higher in active inflammatory bowel disease and giant cell arteritis, as well as in inactive inflammatory bowel disease and giant cell arteritis, than in the non-inflammatory controls. A positive correlation was found between the Crohn's disease activity index and the platelet count, platelet factor 4 and beta-thromboglobulin. Also, a positive correlation was found between the ulcerative colitis activity index and beta-thromboglobulin. However, even after 12 months of follow-up, in Crohn's disease and ulcerative colitis the mean levels of platelet factor 4 and beta-thromboglobulin were significantly higher than the levels of the controls.

CONCLUSION

Platelet factors were correlated with inflammatory bowel disease activity. Levels of platelet factor 4 and beta-thromboglobulin, however, were markedly raised for a long time in clinically inactive inflammatory bowel disease, which might point to a pre-thrombotic state of disease.

The importance of skip lesions in temporal arteritis

AIM

To determine the frequency of skip lesions in an unselected series of temporal artery biopsies and compare the results with other series.

METHODS

The study was a retrospective review of 102 consecutive temporal artery biopsies taken in a five year period (1992-1997) in one large hospital.

RESULTS

35 cases (34.3%) showed evidence of active cranial vasculitis with pathological evidence of inflammation of the intima or media, with or without giant cells. Three of these cases (8.5%) showed apparent skip lesions: normal intima, media, and adventitia in one segment while in other segments there was clear evidence of active vasculitis. Immunocytochemical stains for leucocyte common antigen (LCA) and CD15 were helpful in identifying the absence of intimal or medial inflammatory cell infiltrates within skip lesions. Skip lesions have been described in up to 28.3% of cases in some series, while others have not found evidence of skip lesions or have identified them in a much smaller percentage of cases.

CONCLUSIONS

In this series skip lesions were relatively rare, accounting for 8.5% of cases of active vasculitis. The degree of inflammation in temporal arteritis is discontinuous. Immunostaining for inflammatory cells, for example LCA and CD15, may be helpful in identifying the presence of an inflammatory cell infiltrate in skip lesion segments of the temporal artery.

Presence of antinucleosome autoantibodies in a restricted set of connective tissue diseases: antinucleosome antibodies of the IgG3 subclass are markers of renal pathogenicity in systemic lupus erythematosus

OBJECTIVE

To study the frequency and disease specificity of antinucleosome antibody reactivity in diverse connective tissue diseases (CTD), and to determine factors, such as antibody subclass, that may influence the pathogenicity of these antibodies in relation to disease activity.

METHODS

IgG and IgM antinucleosome activities on nucleosome core particles from 496 patients with 13 different CTD and 100 patients with hepatitis C were measured by enzyme-linked immunosorbent assay (ELISA). Of the patients with CTD, 120 had systemic lupus erythematosus (SLE), 37 had scleroderma (systemic sclerosis; SSc), 20 had mixed connective tissue disease (MCTD), and 319 had other CTD, including Sjögren's syndrome, inflammatory myopathy, rheumatoid arthritis, primary antiphospholipid syndrome, Wegener's granulomatosis, Takayasu arteritis, giant cell arteritis, relapsing polychondritis, Behçet's syndrome, and sarcoidosis. Antinucleosome-positive sera were further analyzed, by isotype-specific ELISA, for antinucleosome and anti-double-stranded DNA (anti-dsDNA) IgG subclasses.

RESULTS

SLE, SSc, and MCTD were the only 3 CTD in which antinucleosome IgG were detected (71.7%, 45.9%, and 45.0% of patients, respectively). Antinucleosomes of the IgG3 subclass were present at high levels in patients with active SLE and were virtually absent in those with SSc, MCTD, or inactive SLE, and their levels showed a positive correlation with SLE disease activity. Of note, an increase in levels of antinucleosome of the IgG3 isotype was observed during SLE flares, and this increase was found to be closely associated with active nephritis. Levels of antinucleosome of the IgG1 subclass showed a trend toward an inverse correlation with SLE disease activity. No significant fluctuation in the anti-dsDNA isotype profile was observed in relation to SLE severity or clinical signs.

CONCLUSION

Our data suggest that IgG antinucleosome is a new marker that may help in the differential diagnosis of CTD; antinucleosome of the IgG3 isotype might constitute a selective biologic marker of active SLE, in particular, of lupus nephritis.

YKL-40 in giant cells and macrophages from patients with giant cell arteritis

OBJECTIVE

YKL-40, a mammalian member of the family 18 glycosyl hydrolases, is secreted by activated macrophages at a late stage of differentiation. Macrophages are present in inflammation of the arterial wall and are thought to participate in the pathogenesis of giant cell arteritis (GCA). The aim of this study was to evaluate whether macrophages and giant cells of patients with GCA produce YKL-40, and whether serum YKL-40 concentrations are elevated in these patients.

METHODS

Serum YKL-40 was determined by radioimmunoassay in 19 patients with GCA and 8 patients with polymyalgia rheumatica (PMR) who were followed up prospectively during 1 year of treatment with prednisolone. Immunohistochemical staining for YKL-40 was performed in temporal artery biopsy samples that were obtained before treatment.

RESULTS

In the arteritic vessels of patients with GCA, positive staining for the YKL-40 antigen was found in CD68+ giant cells and mononuclear cells located in the media. Macrophages located in the adventitia and intima were negative for YKL-40. At the time of diagnosis, patients with GCA had an increased median serum level of YKL-40 (256 microg/liter; P<0.01) compared with healthy age-matched controls (median 118 microg/liter), and the serum level of YKL-40 decreased to normal levels during prednisolone treatment (-38% after 1 month; P<0.001). Most patients with PMR had normal serum YKL-40 levels (median 158 microg/liter) and had no changes in the serum YKL-40 levels during prednisolone treatment. The observed changes in serum YKL-40 did not always parallel the changes in serum C-reactive protein levels and erythrocyte sedimentation rate during the 1-year study period.

CONCLUSION

YKL-40 is found in CD68+ giant cells and mononuclear cells in the media of arteritic vessels of patients with GCA, and the concentration of serum YKL-40 may reflect the local activity of these cells in the inflamed artery.

Comparison of the erythrocyte sedimentation rate measured in the eye casualty department by the Seditainer method with an automated system

PURPOSE

To compare a new automated system for the measurement of erythrocyte sedimentation rate (ESR) with the established manual Seditainer method.

METHODS

Two hundred and twelve patients undergoing investigation for giant cell arteritis or other systemic vasculitides had ESR measurements by both the established manual Seditainer and the new laboratory-based automated system. The results were compared by correlation coefficient and mean difference. The limits of agreement with confidence intervals were also calculated.

RESULTS

Across the range of results from 1 to 120 mm/h, the correlation coefficient was 0.844. The automated method had a mean negative bias of -9.8 mm/h (95% confidence interval: -12.2 to -7.4 mm/h). The wide scatter of results produced limits of agreement (+/- 2 standard deviations) between the two methods of -45 to 26 mm/h. There were seven results that were underestimated by the automated system which were clinically significant.

CONCLUSIONS

There is a wide degree of scatter between the two sets of results. The automated system has a negative bias when compared with the manual method. There is a propensity for the automated system to sporadically underestimate the true result, sometimes to a degree that is clinically significant. The authors therefore cannot recommend replacement of the manual Seditainer system at the present time.

Temporal arteritis: a clinical approach

OBJECTIVE

To develop a clinical guide to the evaluation of temporal arteritis.

DESIGN

A Medline English-language search of the literature from 1966 to 1998, including more than 300 articles about temporal arteritis, was performed to develop a guide to the evaluation of temporal arteritis.

RESULTS

A user-friendly guide to the evaluation of temporal arteritis was developed based on the following criteria: (1) clinical suspicion, (2) laboratory testing, and (3) temporal artery biopsy.

CONCLUSION

A clinical guide to the evaluation of temporal arteritis may assist clinicians in the care of patients with this condition.

[Pathology of large vessel vasculitides]

INTRODUCTION

Vasculitides can be classified according to the size of the involved vessels. The pathological patterns of large vessel vasculitides are presented here.

CURRENT KNOWLEDGE AND KEY POINTS

They concern Buerger's disease, temporal arteritis, Takayasu's disease, Behçet's disease, infectious arteritides, rheumatologic and miscellaneous diseases. Buerger's disease is a thrombotic arteriopathy with no arterial wall involvement. Temporal arteritis and Takayasu's disease belong to the group of giant cell arteritides. In temporal arteritis, the inflammation is prominent in the internal part of the media and is aggressive for the arterial wall. In Takayasu's disease, the external part of the media is prominently involved. The fibrous thickening of the arterial wall with stenosis is characteristic. Behçet's disease can involve the large arteries with a risk of arterial rupture. Infectious arteritides are not unfrequent in vascular surgery and in previous arterial lesions. Rheumatologic diseases can result in aortitis with aortic incompetence.

FUTURE PROSPECTS AND PROJECTS

These diseases have pathological characteristics which contribute to diagnosis. However, a clearcut classification of vasculitides will come from the precise knowledge of their etiology.

Systemic vasculitis in adults in northwestern Spain, 1988-1997. Clinical and epidemiologic aspects

The vasculitides constitute a heterogeneous group of diseases characterized by blood vessel inflammation and necrosis with different but frequently overlapping clinical and pathologic manifestations. The incidence of these conditions is frequently controversial. To further investigate the incidence and clinical manifestations of vasculitides, we reviewed the spectrum of these diseases in an unselected population of adults (age > 20 years) from northwestern Spain during a 10-year period. From January 1988 through December 1997, 267 adults were diagnosed as having vasculitis. The overall average annual incidence rate of vasculitis in the region of Lugo, Spain, between 1988 and 1997 for the population older than 20 years was 141.54/million. Primary vasculitis (115.04/million for the population older than 20 years; 81.3%), especially giant cell arteritis (GCA) was the most common group. Small vessel primary vasculitis (hypersensitivity vasculitis and Henoch-Schönlein purpura) was the second most common group. Both GCA and small vessel primary vasculitis had a good outcome. However, although less common, patients with medium and small vessel primary vasculitis, in particular those with polyarteritis nodosa, had a high mortality related to the systemic manifestations of the disease or to the immunosuppressive therapy. Among the group of adults with secondary vasculitis (26.51/million; 18.7%), rheumatic diseases and specifically those occurring in the context of rheumatoid arthritis were the most common group. Patients with secondary vasculitis had clinical or laboratory data that may suggest the presence of an underlying disease. In summary, systemic vasculitides are somewhat more common than previously considered. As in other western countries, GCA constitutes the most common type of vasculitis in northwestern Spain. Better physician awareness may contribute to the progressive increase in the recognition of these conditions.

Formation of new vasa vasorum in vasculitis. Production of angiogenic cytokines by multinucleated giant cells

Inflammation of the arterial wall in giant cell arteritis induces a series of structural changes, including the formation of new vasa vasorum. To study the regulation of neoangiogenesis in giant cell arteritis, temporal arteries were examined for the extent and localization of microvessel generation and for the production of angiogenic factors. In normal arteries, vasa vasorum were restricted to the adventitia, but in inflamed arteries, capillaries emerged in the media and the intima. These capillaries displayed a distinct topography with a circumferential arrangement in the external one-third of the intima. Neovascularization was closely correlated with the formation of lumen-obstructing intima, the fragmentation of the internal elastic lamina, and the presence of multinucleated giant cells. Comparison of tissue cytokine transcription in temporal arteries of giant cell arteritis patients with and without up-regulated neoangiogenesis identified interferon-gamma and vascular endothelial growth factor but not fibroblast growth factor-2 as mediators associated with vasa vasorum proliferation. Giant cells and CD68-positive macrophages at the media-intima junction were found to be the major cellular sources of vascular endothelial growth factor. These data demonstrate that formation of new vasa vasorum in vasculitis is regulated by inflammatory cells and not by arterial wall cells, raising the possibility that it represents a primary disease mechanism and not a secondary hypoxia-induced event. Increased neovascularization in interferon-gamma-rich arteries suggests that the formation of new vasa vasorum is determined by the nature of the immune response in the arterial wall, possibly resulting from the generation and functional activity of multinucleated giant cells.

Temporal 67gallium uptake is increased in temporal arteritis

OBJECTIVE

We evaluated temporal 67gallium (Ga) uptake in temporal arteritis (TA) and the contribution of Ga scans to the diagnosis of TA.

METHODS

Ga scans were performed prospectively in 19 patients with biopsy-proven TA and five TA patients with negative temporal artery biopsy. Controls were 18 elderly patients undergoing Ga scans for various inflammatory diseases. The temporal region of interest on head profiles was defined for comparison of uptake with a control parietal region of the same area. The Ga uptake ratio (GaUR) [(temporal region - parietal region)/parietal region] was evaluated for each temple by a computer and intra- and intergroup comparisons were made.

RESULTS

GaUR was significantly higher in biopsy-proven TA patients (0.35+/-0.19) and biopsy-negative TA patients (0.31+/-0.03) than in controls (0.18+/-0.12) (P < 0.001), independently of recent temporal artery biopsy or short-duration steroid therapy. High GaUR (>0.4) had a 94% specificity and a 90% positive predictive value for TA diagnosis. After 6 months of steroid therapy, when patients were in remission, GaUR returned to baseline.

CONCLUSION

Ga is specifically incorporated into the temporal area in TA patients which may be due to the granulomatous vasculitic process. Ga uptake ceases during remission. A high GaUR may contribute to TA diagnosis in temporal artery biopsy-negative patients and its role in the diagnosis of other localizations of the disease requires further evaluation.

Efficacy of unilateral versus bilateral temporal artery biopsies for the diagnosis of giant cell arteritis

PURPOSE

To determine the utility of unilateral versus bilateral temporal artery biopsies in detecting the pathologic changes of giant cell arteritis.

METHODS

We performed a retrospective study to determine the utility of unilateral versus bilateral temporal artery biopsies in detecting the pathologic changes of giant cell arteritis. The pathologic reports of consecutive temporal artery biopsy specimens received at the Wilmer Ocular Pathology Laboratory over a 28-year period from 1968 to 1996 were reviewed.

RESULTS

Of 908 specimens examined from 758 patients, 300 specimens were simultaneous bilateral biopsies from 150 patients, 72 specimens were bilateral sequential biopsies from 36 patients, and the remaining 536 specimens were unilateral biopsies from 536 patients. Of the 186 patients who had bilateral simultaneous or nonsimultaneous biopsies, 176 had identical diagnoses on both sides. In four patients, no artery was obtained on one side. In each of the remaining six patients, five of whom had bilateral simultaneous biopsies and one of whom had bilateral sequential biopsies performed 8 days apart, the biopsy specimen from one side was interpreted as showing only arteriosclerotic changes with no evidence of active or healed arteritis, whereas the other specimen was interpreted as showing either probable healed arteritis (three specimens) or possible early arteritis (three cases). In none of the six patients with differing diagnoses between the two sides was one side interpreted as showing definite, active giant cell arteritis. Five of the six patients were subsequently determined to have giant cell arteritis, based on a combination of clinical findings, erythrocyte sedimentation rate, and response to treatment with systemic corticosteroids.

CONCLUSIONS

The results of this study indicate that performing a bilateral simultaneous or sequential temporal artery biopsy improves the diagnostic yield in at least 3% of cases of giant cell arteritis, whereas in 97% of cases, the two specimens show the same findings. Thus, in patients in whom only one artery can be biopsied, there is a high probability of obtaining the correct diagnosis. Nevertheless, although the improvement in diagnostic yield of bilateral temporal artery biopsies is low, the consequences of both delayed diagnosis and treatment of giant cell arteritis as well as the use of systemic corticosteroids in patients who do not have giant cell arteritis are of such potential severity that consideration should always be given to performing bilateral temporal artery biopsies in patients suspected of having the disease.

[Prevalence of antiphospholipid antibodies in Horton's disease and in polymyalgia rheumatica]

PURPOSE

Antiphospholipid antibodies (APL) are frequently observed in the course of giant cell arteritis and polymyalgia rheumatica. However, their role and relationships with potential ischemic events are still debated.

METHODS

To determine the prevalence of APL in relation with ischemic events, 62 patients with giant cell arteritis and/or polymyalgia rheumatica were retrospectively studied.

RESULTS

Before corticosteroid treatment 41% of the 51 patients with giant cell arteritis and 64% of the 11 patients with isolated polymyalgic rheumatica had high IgG ACL levels, with a frequency significantly higher than that (15.6%) of the control group which was composed of healthy elderly. IgM ACL were found in only two patients with giant cell arteritis. There was no correlation between the occurrence of an ischemic event (22 ischemic events in the 51 patients with giant cell arteritis) and the presence of ACL, even though the latter were more frequently observed in the giant cell arteritis group (52% versus 41% in non ischemic patients). The prevalence of ACL increased, reaching 59% if lupus anticoagulant was associated, but the difference was not significant. ACL disappeared soon after corticosteroid therapy had been initiated.

CONCLUSION

Though ACL are frequently seen in giant cell arteritis and/or polymyalgia rheumatica, they are not related to ischemic events and disappear rapidly after corticosteroid treatment.

Visual performance in giant cell arteritis (temporal arteritis) after 1 year of therapy

AIMS

To determine if patients with giant cell arteritis (GCA) treated with corticosteroids develop delayed visual loss or drug related ocular complications.

METHODS

In a multicentre prospective study patients with GCA (using precise diagnostic criteria) had ophthalmic evaluations at predetermined intervals up to 1 year. The dose of corticosteroid was determined by treating physicians, often outside the study, with the daily dose reduced to the equivalent of 30-40 mg of prednisone within 5 weeks. Subsequently, treatment guidelines suggested that the dose be reduced as tolerated or the patient was withdrawn from steroids in a period not less than 6 months.

RESULTS

At presentation, of the 22 patients enrolled, seven patients had nine eyes with ischaemic injury. Four eyes had improved visual acuity by two lines or more within 1 month of starting corticosteroids. No patients developed late visual loss as the steroid dose was reduced. At 1 year the visual acuity, contrast sensitivity, colour vision, and threshold perimetry were not significantly different from the 4-5 week determinations. At 1 year, there were no significant cataractous or glaucomatous changes. At 2 months, there was no difference in systemic complications between patients who received conventional dose (60-80 mg per day) or very high doses (200-1000 mg per day) of corticosteroids at the start or early in the course.

CONCLUSIONS

Patients with GCA related visual loss can improve with treatment. Corticosteroids with starting doses of 60-1000 mg per day, with reduction to daily doses of 40-50 mg per day given for 4-6 weeks, and gradual dose reduction thereafter, as clinically permitted, did not result in delayed visual loss. There were no significant drug related ophthalmic complications.

Musculoskeletal manifestations in a population-based cohort of patients with giant cell arteritis

OBJECTIVE

To define musculoskeletal manifestations occurring in a population-based cohort of patients with giant cell (temporal) arteritis (GCA).

METHODS

The records of 128 patients with GCA diagnosed over a 42-year-period (1950-1991) in Olmsted County, MN, were reviewed for the presence and type of musculoskeletal manifestations, their relationship to the onset and course of GCA, and their response to treatment.

RESULTS

Fifty-three patients (41%) developed polymyalgia rheumatica: 23 before, 17 concurrently with, and 13 after the diagnosis of GCA. Thirty patients (23%) developed 1 or more peripheral musculoskeletal manifestations. These included peripheral synovitis in 23 patients (6 of whom fulfilled criteria for rheumatoid arthritis), distal extremity swelling with pitting edema in 13, distal swelling without pitting in 5, tenosynovitis in 6, and carpal tunnel syndrome in 2. Fifty-seven episodes of peripheral manifestations occurred in the 30 patients at different times during the course of GCA. In most, the onset of PMR and peripheral manifestations was within 2 years of the diagnosis of GCA.

CONCLUSION

Musculoskeletal symptoms in GCA are common and varied. Most appear linked temporally to the underlying GCA, indicating that the nature of this illness and its clinical expression are broader than often considered.

Giant cell arteritis update

Giant cell arteritis (GCA) is a systemic disorder characterized by vasculitis involving medium and large arteries. GCA is an ophthalmologic and systemic emergency, because devastating consequences, such as blindness and death, can occur without treatment. With prompt recognition and appropriate treatment, complications are almost always preventable. The prognosis for recovery of vision already lost because of GCA is usually poor, underscoring the absolute necessity of immediate intervention. Knowledge of the various manifestations of GCA is essential for recognition of this disorder early enough to prevent complications. This article highlights the important points regarding diagnosis, management, and complications associated with treatment of GCA.

Biopsy proven and biopsy negative temporal arteritis: differences in clinical spectrum at the onset of the disease. Groupe de Recherche sur l'Artérite à Cellules Géantes

OBJECTIVES

To assess the clinical features of biopsy proven and negative biopsy temporal arteritis at the time of diagnosis and during a three year follow up.

METHODS

Newly diagnosed cases of giant cell arteritis were included in a prospective, multicentre study. Initial clinical and biological features, season of diagnosis, and cardiovascular events occurring during the follow up were recorded. Biopsy proven and negative biopsy cases were compared.

RESULTS

Two hundred and seven biopsy proven, and 85 negative biopsy cases were included from 1991 to 1997. Fifty eight per cent of the biopsy proven cases, compared with 39.29% of the negative biopsy cases, were diagnosed during the autumn or winter (p = 0.003). Visual problems (31.5%, v 19.1%, p = 0.031), blindness (9.7% v 2.38%, p = 0.033), jaw claudication (40.8%, v 28.243%, p = 0.044), and temporal artery palpation abnormalities (61.3% v 29.5%, p = 7.10(-7)) were more frequent in the biopsy proven than in the negative biopsy group. Less specific symptoms, such as headache (82.5% v 92. 9%, p = 0.021), or associated polymyalgia rheumatica (40.1% v 65.9%, p = 9 x 10(-5)) were more prevalent in the negative biopsy cases. Biological markers of inflammation were significantly more increased in the biopsy proven group. All cases of blindness occurring after treatment belonged to the biopsy proven group.

CONCLUSION

Biopsy proven cases seem to be more severe than biopsy negative cases at the time of diagnosis and during follow up. Seasonal difference at diagnosis may suggest a different aetiological pattern.

Giant Cell Arteritis

Diagnosis and management of giant cell (temporal) arteritis (GCA) should be performed by physicians who can accurately monitor the ophthalmologic, neurologic, and systemic sequelae of the disease as well as the numerous side effects of systemic corticosteroids, which are typically necessary for treatment. When the diagnosis of giant cell arteritis is seriously entertained, early treatment with adequate doses of oral or intravenous corticosteroids should not be delayed until laboratory confirmation has been obtained. Unilateral or bilateral temporal artery biopsy should be performed on all patients with suspected GCA. A positive biopsy result mandates that higher doses of corticosteroids be used during the first 2 months, which comprise the critical period for risk of new ocular ischemia. A definitive, biopsy-proven diagnosis requires at least 6 months, and typically 12 months, of corticosteroid therapy. Common pitfalls include increasing the dose and prolonging the use of corticosteroids in response to increases in the erythrocyte sedimentation rate (ESR) unrelated to GCA or visual blurring that may be related to benign tear film abnormalities, corticosteroid-induced lens changes, and other ophthalmic conditions. The muscle stiffness of polymyalgia rheumatica (PMR) must be distinguished from the osteoarthritis and other painful conditions common in the elderly. After corticosteroid therapy has begun, continuing ophthalmologic evaluation is necessary to evaluate the effectiveness of treatment and whether ocular complications, such as glaucoma or cataract, develop. Careful attention must be given to early detection and prevention of systemic side effects of corticosteroid treatment. Patients may be given gastrointestinal protective agents, such as histamine (H(2))-blocking agents; vitamin D and calcium; oral hypoglycemic agents; and, if necessary, insulin and antihypertensive drugs. If bone density measurements warrant, hormones/supplementation to prevent or reverse osteoporosis may be prescribed. After the initial diagnosis and first 4 weeks of treatment, elevation of the ESR or C-reactive protein alone should generally not be used as signs of disease activity nor as a reason to increase the daily dose of steroids. If symptoms or signs of disease activity occur, the dose should be raised regardless of test results. Even with vigorous physician-patient education, however, a patient is occasionally unable to provide adequate historical information about response to therapy, and the physician is forced to rely on laboratory values as a measure of disease activity. After initial high-dose corticosteroid therapy, patients without a classic history and with negative biopsy results will generally receive a rapid taper to low doses of corticosteroids. The role of repeated temporal artery biopsy in the clinical management of GCA is unclear. Despite persistence of PMR and, in some cases, histologic evidence of inflammation in temporal arteries, patients do not frequently have recurrence of symptomatic GCA after 6 months or more of corticosteroid therapy. Under these circumstances, late vision loss is rare.

Disease pattern in cranial and large-vessel giant cell arteritis

OBJECTIVE

To identify variables that distinguish large-vessel giant cell arteritis (GCA) with subclavian/axillary/brachial artery involvement from cranial GCA.

METHODS

Seventy-four case patients with subclavian/axillary GCA diagnosed by angiography and 74 control patients with temporal artery biopsy-proven GCA without large vessel involvement matched for the date of first diagnosis were identified. Pertinent initial symptoms, time delay until diagnosis, and clinical symptoms, as well as clinical and laboratory findings at the time of diagnosis, were recorded by retrospective chart review. Expression of cytokine messenger RNA in temporal artery tissue from patients with large-vessel and cranial GCA was determined by semiquantitative polymerase chain reaction analysis. Distribution of disease-associated HLA-DRB1 alleles in patients with aortic arch syndrome and cranial GCA was assessed.

RESULTS

The clinical presentation distinguished patients with large-vessel GCA from those with classic cranial GCA. Upper extremity vascular insufficiency dominated the clinical presentation of patients with large-vessel GCA, whereas symptoms related to impaired cranial blood flow were infrequent. Temporal artery biopsy findings were negative in 42% of patients with large-vessel GCA. Polymyalgia rheumatica occurred with similar frequency in both patient groups. Large-vessel GCA was associated with higher concentrations of interleukin-2 gene transcripts in arterial tissue and overrepresentation of the HLA-DRB1*0404 allele, indicating differences in pathogenetic mechanisms.

CONCLUSION

GCA is not a single entity but includes several variants of disease. Large-vessel GCA produces a distinct spectrum of clinical manifestations and often occurs without involvement of the cranial arteries. Large-vessel GCA requires a different approach to the diagnosis and probably also to treatment.

A 69-year-old woman with intermittent claudication and elevated ESR

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Primary vasculitis in a Norwegian community hospital: a retrospective study

Primary systemic vasculitic diseases are relatively rare. Untreated, they have a high morbidity and mortality. The introduction of steroids and cytotoxic drugs has dramatically reduced the mortality. In a retrospective study in a Norwegian community hospital, which serves a county with a population of 150,426 in 1996, 68 patients were found to have a primary vasculitis, 63 of whom fulfilled the ACR 1990 criteria. Patients with Henoch-Schönlein purpura aged less than 16 years and patients with Kawasaki's disease were excluded. The overall prevalence was 43.9 per 100,000 inhabitants (Churg-Strauss syndrome 1.3, hypersensitivity vasculitis 2.7, Henoch-Schönlein purpura 3.3, polyarteritis nodosa 3.3, Wegener's granulomatosis 5.3 and temporal arteritis 27.9). In most cases, disease control was achieved with corticosteroids alone, or with the addition of cytotoxic drugs. Two patients had died in the latest 5-year period but of unrelated disorders. Biopsy plays a major role in diagnosing vasculitic diseases. In our study, 62 patients had a positive biopsy supporting the diagnosis.

Unusual headaches

Headache represents one of the most common somatic complaints seen in the emergency department, accounting for 1% to 3% of all emergency department visits. Although most headaches seen in the emergency department are benign, as many as 10% of all headaches are secondary to an underlying pathologic condition. The emergency physician is well-trained to exclude stoke, subarachnoid hemorrhage, and meningitis as potential causes of headache. This article focuses on seven unusual headache syndromes, all of which are associated with significant morbidity and mortality. Particular emphasis is placed on clinical features and diagnostic modalities of choice.

Giant cell arteritis and cardiovascular risk factors: a multicenter, prospective case-control study. Groupe de Recherche sur l'Artérite à Cellules Géantes

OBJECTIVE

To assess the role of cardiovascular risk factors, measured at the time of diagnosis, in the pathogenesis of giant cell (temporal) arteritis (GCA).

METHODS

Four hundred new patients with GCA or polymyalgia rheumatica (PMR) and population-based, individually age- and sex-matched controls were included in this multicenter, prospective case-control study. Each participant was evaluated by review of the medical history and by clinical and laboratory assessments.

RESULTS

Among women, smoking was associated with a 6-fold increase in risk (P = 0.00006, 95% confidence interval [95% CI] 2-17), heavy smoking with a 17-fold increase in risk, and previous atheromatous disease with a 4.5-fold increase in risk (P = 0.0003, 95% CI 2-11) of GCA in both the biopsy-positive and biopsy-negative GCA groups; only smoking appeared to be a risk factor for PMR in women (odds ratio 3.64, 95% CI 1.07-12.40). Among men, no risk factor was found to be significant.

CONCLUSION

Smoking and previous arterial disease were independently associated with GCA in women. In order to avoid matching bias, risk factors for diseases with an unbalanced sex distribution should be studied separately in each sex, using a sex-matched, case-control study design.

Permanent visual loss and cerebrovascular accidents in giant cell arteritis: predictors and response to treatment

OBJECTIVE

To assess the features and therapeutic response of visual manifestations and cerebrovascular accidents (CVA) in giant cell (temporal) arteritis (GCA) and to identify the predictors for permanent visual loss (VL) and CVA in GCA.

METHODS

Two hundred thirty-nine patients with biopsy-proven GCA were included in a retrospective multicenter study. Data on demographic, clinical, and laboratory features were collected. The predictors were identified by a forward stepwise nonconditional logistic regression analysis.

RESULTS

Visual involvement was observed in 69 patients, and 34 had permanent VL. The diagnostic delay since the onset of visual symptoms was longer in the 11 patients with bilateral VL. The interval to involvement of the second eye was 5 days. The predictors of permanent VL were transient VL, jaw claudication, normal levels of liver enzymes, and absence of constitutional syndrome. Partial improvement of visual acuity was observed in 8 patients. After adjustment for the treatment regimen (intravenous pulse methylprednisolone versus oral prednisone), early treatment (within the first day of VL) was the only predictor of improvement. CVA, observed in 8 patients, involved the vertebral-basilar territory in 4. CVA was more frequent in patients with visual symptoms, appearing shortly after VL (median 7 days) and despite appropriate therapy. Predictors of CVA were permanent VL and jaw claudication.

CONCLUSION

In GCA, the risk of permanent VL is increased in patients with transient VL and/or jaw claudication, and decreased in those with elevated liver enzyme levels and/or constitutional syndrome. Partial therapeutic success is more probable if treatment is started within the first day of VL. CVA is more likely in patients with permanent VL and/or jaw claudication, often developing despite appropriate corticosteroid therapy.

Relation between HLA DRB1 alleles and corticosteroid resistance in giant cell arteritis

OBJECTIVE

To evaluate the clinical usefulness of genomic HLA typing during the first two years of established giant cell arteritis (GCA).

METHODS

HLA typing was performed by PCR-SSO in 41 selected white patients with GCA confirmed by biopsy. Patient data were compared with those of a control group of 384 bone marrow donors (relative risk, p value and chi 2 test for each allele). Clinical features at onset and response to treatment over a two year period were evaluated in relation to the genetic pattern.

RESULTS

DRB1*04 was significantly increased in the GCA group (frequency of 48.78% compared with 19.79% in controls, p < 0.001). The distribution of the DRB1*04 subtypes in the GCA group was similar to that in controls. No clinical or biological differences were found in association with HLA at the time of diagnosis. Over the two year follow up, nine patients presented resistance to corticosteroid treatment and eight of these (88.88%) had DRB1*04 (p < 0.001).

CONCLUSIONS

GCA seems to be associated with HLA DRB1*04 (regardless of the subtype) and this association appears to be accompanied by corticosteroid resistance, suggesting that genomic typing may be useful to identify patients eligible for early alternative treatment to corticosteroid drugs.

The binding of some human antiendothelial cell antibodies induces endothelial cell apoptosis

The pathogenic role of antiendothelial cell antibodies (AECA) remains unclear. They are frequently associated with antibodies to anionic phospholipids (PL), such as phosphatidylserine (PS), which is difficult to reconcile with the distribution of PL molecular species within the plasma membrane. Since it is already known that PS is transferred to the outer face of the membrane as a preclude to apoptosis, the possibility exists that apoptosis is initiated by AECA. AECA-positive/anti-PL antibody-negative sera from eight patients with systemic sclerosis (SS) and 21 control patients were evaluated. Endothelial cells (EC) were incubated with AECA and the exposure of PS was established through the binding of annexin V. Hypoploid cell enumeration, DNA fragmentation, and optical and ultrastructural analyses of EC were used to confirm apoptosis. Incubation of EC with AECA derived from six of eight patients with SS led to the expression of PS on the surface of the cells. This phenomenon was significantly more frequent in SS (P < 0.04) than in control diseases. The redistribution of plasma membrane PS preceded other events associated with apoptosis: hypoploidy, DNA fragmentation, and morphology characteristic for apoptosis. Apoptosis-inducing AECA did not recognize the Fas receptor. We conclude that AECA may be pathogenic by inducing apoptosis.

Estimates of the prevalence of arthritis and selected musculoskeletal disorders in the United States

OBJECTIVE

To provide a single source for the best available estimates of the national prevalence of arthritis in general and of selected musculoskeletal disorders (osteoarthritis, rheumatoid arthritis, juvenile rheumatoid arthritis, the spondylarthropathies, systemic lupus erythematosus, scleroderma, polymyalgia rheumatica/giant cell arteritis, gout, fibromyalgia, and low back pain).

METHODS

The National Arthritis Data Workgroup reviewed data from available surveys, such as the National Health and Nutrition Examination Survey series. For overall national estimates, we used surveys based on representative samples. Because data based on national population samples are unavailable for most specific musculoskeletal conditions, we derived data from various smaller survey samples from defined populations. Prevalence estimates from these surveys were linked to 1990 US Bureau of the Census population data to calculate national estimates. We also estimated the expected frequency of arthritis in the year 2020.

RESULTS

Current national estimates are provided, with important caveats regarding their interpretation, for self-reported arthritis and selected conditions. An estimated 15% (40 million) of Americans had some form of arthritis in 1995. By the year 2020, an estimated 18.2% (59.4 million) will be affected.

CONCLUSION

Given the limitations of the data on which they are based, this report provides the best available prevalence estimates for arthritis and other rheumatic conditions overall, and for selected musculoskeletal disorders, in the US population.

Two populations of endothelial cell antibodies cross-react with heparin

As endothelial cells (EC) express heparin-like glycosaminoglycans, such as heparan sulfate, it was essential to investigate the relation of anti-EC antibody (AECA) to heparin reactivity. AECA were detected in 43 of 131 autoimmune sera and anti-heparin antibodies (AHA) in 25. These autoimmune reactivities were significantly associated (P corrected < 0.0005). Seven AECA-positive/AHA-positive and three AECA-negative/AHA-positive sera were affinity-purified using protein G column followed by a heparin-Sepharose column. Two populations of AECA were recovered from the second column. One was eluted with 0.4 M NaCl which bound to EC and to solid-phase heparin with low affinity, but not to soluble heparin. The second population of AECA, which was eluted with 4 M guanidine HCl/2 M NaCl, recognized EC and solid-phase heparin with high affinity, but also soluble heparin. The latter population of AECA might thus be an important cause of autoimmune vascular thrombosis in systemic diseases.

Anticardiolipin antibodies and giant cell arteritis: a prospective, multicenter case-control study. Groupe de Recherche sur l'Artérite à Cellules Géantes

OBJECTIVE

To assess the prevalence and thrombogenic role of anticardiolipin antibodies (aCL) in giant cell arteritis.

METHODS

Two hundred eighty-four patients with newly diagnosed temporal arteritis or polymyalgia rheumatica and 210 age- and sex-matched controls randomly selected from the general population were included in a multicenter, prospective case-control study. Blood samples were obtained at the time of diagnosis, data on initial clinical features were collected in a questionnaire, and temporal artery biopsy findings were reviewed by an experienced pathologist.

RESULTS

Anticardiolipin antibodies were present in 20.7% of patients compared with 2.9% of controls (P = 1.45 x 10(-9)). The prevalence of aCL was higher in samples found positive for temporal arteritis than in those found negative on biopsy (31.2% versus 16.7%; P = 0.04), and was similarly higher in the biopsy-positive temporal arteritis group compared with the polymyalgia rheumatica and control groups. Although aCL were associated with thrombotic complications in univariate analysis, the positivity of the biopsy findings remained the only predictive variable in stratified analysis.

CONCLUSION

In giant cell arteritis, aCL seem to function as reactive antibodies in relation to endothelial lesions.

Platelet-derived growth factor, intimal hyperplasia, and ischemic complications in giant cell arteritis

OBJECTIVE

To explore whether vasoocclusion in giant cell (temporal) arteritis (GCA) is related to intimal hyperplasia and in situ production of platelet-derived growth factor (PDGF).

METHODS

Temporal artery biopsy specimens from patients with GCA were analyzed for the presence of intimal hyperplasia. Expression of PDGF-A and PDGF-B was assessed by immunohistochemistry and digitized image analysis.

RESULTS

PDGF-A and PDGF-B were widely expressed in inflamed arteries. CD68+ macrophages, smooth muscle cells, and multinucleated giant cells produced PDGF, whereas hyperplastic intimal tissue did not. Arteries with marked luminal narrowing and those with no or minimal luminal narrowing differed in the extent and distribution of PDGF expression. Concentric intimal hyperplasia was associated with the accumulation of PDGF-A- and PDGF-B-producing CD68+ macrophages at the media-intima junction. PDGF+,CD68+ macrophages in close proximity to the internal elastic lamina frequently coproduced matrix metalloproteinase 2. Intimal hyperplasia of the temporal artery correlated with ischemic complications of GCA, such as ocular involvement, jaw claudication, and aortic arch syndrome.

CONCLUSION

Production of PDGF has a role in arterial occlusion in GCA. The excessive fibroproliferative response leading to luminal narrowing can be distinguished from the stenosing process in atherosclerosis and postangioplasty restenosis, suggesting that there are different response patterns to arterial injury. In GCA, macrophages at the media-intima border are the dominant source of PDGF. Since vasoocclusion is associated with a number of serious complications in GCA, inhibition of intimal proliferation should be a major goal of treatment.

Masticatory muscle pain: an important indicator of giant cell arteritis

Giant cell arteritis (GCA) is a polysymptomatic disease which constitutes an ophthalmic emergency because early recognition and management can prevent blindness. There is conflicting information in the literature on the validity, sensitivity, and specificity of various systemic symptoms and signs of GCA. This paper presents a review of our prospective studies on the subject, and our findings are particularly relevant to dentists. We investigated 363 patients in a prospective study. Positive temporal artery biopsy was seen in 106 patients and negative in 257 referred for diagnosis of GCA. Systemic symptoms and signs of GCA and erythrocyte sedimentation rate (Westergren-ESR) and C-reactive protein (CRP) levels were compared in these two groups of patients. The odds of having a positive temporal artery biopsy (i.e., GCA) were 9.1 times greater with jaw claudication (pain in masticatory muscles on eating), 3.4 times with neck pain, 3.2 times with CRP > 2.45 mg/dL, 2.0 times with ESR 47.107 mm/hr, 2.7 times with ESR > 107 mm/hr, and 2.0 times when the patients were aged > or = 75 years. Other signs and symptoms did not show a significant association with a positive biopsy. Our study showed that "normal" ESR values do not rule out GCA but that CRP is a more useful test than ESR. Since jaw claudication is one of the most important symptoms of GCA, dentists should keep this possibility in mind when older patients come complaining of jaw pain while eating.

Color duplex ultrasonography in the diagnosis of temporal arteritis

BACKGROUND

The diagnosis of temporal arteritis usually requires a biopsy of the temporal artery. We examined the usefulness of color duplex ultrasonography in patients suspected of having temporal arteritis.

METHODS

In this prospective study, all patients seen in the departments of rheumatology and ophthalmology from January 1994 to October 1996 who had clinically suspected active temporal arteritis or polymyalgia rheumatica were examined by duplex ultrasonography. The final diagnoses, made according to standard criteria, were temporal arteritis in 30 patients, 21 with biopsy-confirmed disease; polymyalgia rheumatica in 37; and negative histologic findings and a diagnosis other than temporal arteritis or polymyalgia rheumatica in 15. We also studied 30 control patients matched for age and sex to the patients with arteritis. Two ultrasound studies were performed and read before the biopsies; one ultrasonographer was unaware of the clinical information.

RESULTS

In 22 (73 percent) of the 30 patients with temporal arteritis, ultrasonography showed a dark halo around the lumen of the temporal arteries. The halos disappeared after a mean of 16 days (range, 7 to 56) of treatment with corticosteroids. Twenty-four patients (80 percent) had stenoses or occlusions of temporal-artery segments, and 28 patients (93 percent) had stenoses, occlusions, or a halo. No halos were identified in the 82 patients without temporal arteritis; 6 (7 percent) had stenoses or occlusions. For each of the three types of abnormalities identified by ultrasonography, the interrater agreement was > or =95 percent.

CONCLUSIONS

There are characteristic signs of temporal arteritis that can be visualized by color duplex ultrasonography. The most specific sign is a dark halo, which may be due to edema of the artery wall. In patients with typical clinical signs and a halo on ultrasonography, it may be possible to make a diagnosis of temporal arteritis and begin treatment without performing a temporal-artery biopsy.

Current concepts in giant cell (temporal) arteritis

Giant cell (temporal) arteritis continues to be a sight-threatening, systemic vasculitis with a poorly understood pathogenesis. The characteristic granulomatous inflammation of the vessel wall commonly leads to local ischemia. Recent advances in immunological investigations have characterized the cellular components of the disease process, but the etiology has so far remained unresolved. A reappraisal of the clinical features of giant cell (temporal) arteritis demonstrates the heterogeneity of the manifestations of the disease, including ischemic optic neuropathy. A range of new laboratory investigations and blood flow studies with color Doppler imaging have demonstrated promising roles, with respect to diagnosis and long-term follow-up. Prompt diagnosis and expeditious treatment require a high index of clinical suspicion, particularly for atypical cases. Corticosteroids remain the treatment of choice, other immuno-suppressive agents being used as second line steroid-sparing agents. Giant cell (temporal) arteritis leads to increased vascular and visual morbidity and, if untreated, may prove fatal. To maintain high standards of management of this enigmatic disorder, ophthalmologists need to be aware of the clinical spectrum of giant cell (temporal) arteritis and currently available diagnostic tests and treatment strategies.

Classification and epidemiology of the vasculitides

The systemic vasculitides are rare inflammatory conditions of blood vessel walls. A number of different classification schemes have been published since the first in 1952. The important developments have been the recognition of dominant blood vessel size, the distinction between primary and secondary vasculitis and the incorporation of pathogenic markers such as anti-neutrophil cytoplasmic antibodies. In 1990 the American College of Rheumatology (ACR) published criteria for the diagnosis of polyarteritis nodosa, Churg-Strauss syndrome, Wegener's granulomatosis, hypersensitivity vasculitis, Schönlein-Henoch purpura, giant cell arteritis and Takayasu arteritis. Sensitivity and specificity rates varied considerably: 71.0-95.3% for sensitivity and 78.7-99.7% for specificity. The criteria were not tested against the general population or against patients with other connective tissue diseases or rheumatic conditions. Four years later the Chapel Hill Consensus Conference (CHCC) produced definitions for the major types of vasculitis, however, these have proved controversial. Comparison in unselected patients with systemic vasculitis (in particular polyarteritis nodosa and microscopic polyangiitis) has shown that the ACR criteria and CHCC definitions identify different patients. The systemic vasculitides are somewhat more common than previously believed. The overall annual incidence approaches 40/million adults. The most common form of primary systemic vasculitis is giant cell arteritis; Wegener's granulomatosis, microscopic polyangiitis and Churg-Strauss syndrome have similar incidences. Classical polyarteritis nodosa and Takayasu arteritis are very rare in the UK.

Large vessel vasculitis (giant cell arteritis, Takayasu arteritis)

Giant cell arteritis and Takayasu arteritis are separate but similar idiopathic diseases clinically characterized by constitutional symptoms, shared surrogate markers of systemic inflammation and indistinguishable granulomatous pan-arteritis of large vessels. This review emphasizes and analyses changing perceptions about the diseases. Recent series suggest that aortic involvement in giant cell arteritis may be more common than was previously appreciated. The case for and against inflammatory arthritis in giant cell arteritis is discussed. Ethnic new geographical variation in Takayasu arteritis-disease expression is reviewed. New philosophies of treatment are presented for both diseases. Prognosis in giant cell arteritis and its relationship to treatment is analysed. The utility of the laboratory for diagnosis and monitoring disease activity is appraised for each.

Risk factors and predictive models of giant cell arteritis in polymyalgia rheumatica

OBJECTIVE

To identify in polymyalgia rheumatica the best set of predictors for a positive temporal artery biopsy and to define predictive models with either a high or low probability of giant cell arteritis (GCA).

PATIENTS AND METHODS

Retrospective study of 227 patients, 137 with polymyalgia rheumatica unassociated with arteritis (group A) and 90 with polymyalgia associated with biopsy-proven giant cell arteritis (group B or training set). Data on demographic features, clinical and laboratory abnormalities were collected. Risk factors for arteritis were estimated by nonlinear logistic regressions. Simple predictive models were constructed with those predictors more related to arteritis by multivariable analysis. These models were then tested in group B and in 89 cases of arteritis without polymyalgia rheumatica (group C or test set).

RESULTS

The best predictors of arteritis were a new headache odds ratio (OR) 13.6 (95% confidence interval [CI] 4.7 to 39.3); age at onset < 70 years OR 0.11 (CI 0.04 to 0.35); abnormal temporal arteries OR 4.2 (CI 1.3 to 13.7); raised liver enzymes OR 2.9 (CI 1.1 to 7.8), and jaw claudication OR 4.8 (CI 1.0 to 22.7). Amaurosis was only observed in patients with arteritis. Three subsets had a very high risk of arteritis: (1) Patients with recent headache, abnormal arteries, and > or = 70 years at disease onset: sensitivity 44%, positive predictive value (PPV) 93%, likelihood ratio (LR) 20.3; (2) patients with a new headache, jaw claudication, and abnormal arteries: sensitivity 34.4%, PPV 96.9%, LR 47.2; and (3) those, that in addition to the last 3 features, were > or = 70 years of age at disease onset: sensitivity 26.7%, PPV 100%. We could also identify a subset with a very low risk of arteritis constituted by patients < 70 years, without headache, and with clinically normal temporal arteries: sensitivity 1.1%, PPV 1.7%, LR 0.03. In group C or the test set, these four predictive models correctly identified 57.3%, 29.2%, 23.6, and 3.4% of patients, respectively.

CONCLUSIONS

In polymyalgia rheumatica it is feasible to identify subsets with a very high likelihood of GCA. Although in some of these subsets the diagnosis of arteritis is almost certain, we suggest that even then it should be confirmed by temporal artery biopsy. By contrast, in those patients with polymyalgia < 70 years and without cranial features of giant cell arteritis, the risk of vasculitis is so low that the biopsy could be initially avoided and the patient treated with low-dose corticosteroids.

Giant cell arteritis: validity and reliability of various diagnostic criteria

PURPOSE

To ascertain the validity, reliability, sensitivity, and specificity of various signs and symptoms of and diagnostic tests for early diagnosis of giant cell arteritis.

METHODS

From 1973 to 1994, we studied 363 patients who had temporal artery biopsy for suspected giant cell arteritis. All patients underwent detailed clinical evaluation and had erythrocyte sedimentation rates determined; since 1985, 223 patients had their C-reactive protein values estimated. Erythrocyte sedimentation rate and C-reactive protein levels were also estimated in 749 and 138 control subjects, respectively. Signs and symptoms of giant cell arteritis, erythrocyte sedimentation rate, and C-reactive protein levels among patients with positive and negative biopsies were compared.

RESULTS

Of the 363 patients, temporal artery biopsy was positive in 106 and negative in 257. The odds of a positive biopsy were 9.0 times greater with jaw claudication (P < .0001), 3.4 times greater with neck pain (P = .0085), 2.0 times greater with an erythrocyte sedimentation rate of 47 to 107 mm/hour (P = .0454), 3.2 times greater with C-reactive protein above 2.45 mg/dl (P = .0208), and 2.0 times greater for age 75 years or more (P = .0105).

CONCLUSIONS

Clinical criteria most strongly suggestive of giant cell arteritis include jaw claudication, C-reactive protein above 2.45 mg/dl, neck pain, and an erythrocyte sedimentation rate of 47 mm/hour or more, in that order. C-reactive protein was more sensitive (100%) than erythrocyte sedimentation rate (92%) for detection of giant cell arteritis; erythrocyte sedimentation rate combined with C-reactive protein gave the best specificity (97%).

Giant cell arteritis and polymyalgia rheumatica

Giant cell arteritis and polymyalgia rheumatica are linked conditions that frequently occur in the same patient. They are more common in northern Europe and persons of European descent than in other populations. Recent investigations have begun to provide information about the pathogenesis of both syndromes. Both respond to corticosteroids but at different dose levels. Although a number of vascular complications may occur, the outlook is excellent.