GIANT CELL ARTERITIS

Baseline clinical predictors of an ultimate giant cell arteritis diagnosis in patients referred to temporal artery biopsy

The diagnosis of giant cell arteritis (GCA) is based on clinical grounds and confirmed by characteristic histological findings on temporal artery biopsy (TAB). Patients may be diagnosed with GCA based on clinical grounds only, despite negative histological findings. We aimed to investigate which baseline clinical and laboratory features best predict an ultimate diagnosis of giant cell arteritis among patients referred to TAB. We retrospectively analyzed 224 patients who underwent TAB in our hospital between 2000 and 2014. Patients were diagnosed with GCA if TAB was positive for GCA, or by clinical grounds only despite a negative biopsy, provided they fulfilled the American College of Rheumatology 1990 criteria. Baseline clinical and laboratory features were obtained from medical records. Predictors of an ultimate GCA diagnosis were investigated. Overall, 82 patients were diagnosed with GCA-57 had histological evidence of GCA and 25 were diagnosed with GCA despite a negative biopsy. One hundred and forty-two patients were not diagnosed with GCA. Predictors of an eventual diagnosis of GCA in a multivariate logistic regression analysis were headache (OR = 6; p < 0.001), jaw claudication (OR 4.5; p = 0.007), erythrocyte sedimentation rate (ESR) (OR = 1.5; p = 0.032) and platelet count (OR = 1.74; p = 0.004). Among patients referred to TAB, headache, jaw claudication, ESR, and thrombocyte levels are predictors for an ultimate diagnosis of GCA. These clinical and laboratory features should be considered when contemplating the diagnosis and treatment of GCA.

Transient monocular visual loss

Transient monocular visual loss is an important clinical complaint and has a number of causes, of which the most common is retinal ischemia. A practical approach is to perform a careful examination to determine whether there are any eye abnormalities that can explain the visual loss. Despite the transient nature of the symptom, there may be clues to the diagnosis on the examination even after the visual loss has recovered.

Giant cell arteritis

Giant cell arteritis (GCA) is an immune-mediated vasculitis, affecting medium- to large-sized arteries, in individuals over the age of 50 years. Visual loss is a frequent complication of GCA, and once it occurs it tends to be both permanent and profound. Although major advances have been made in recent years in genetics, molecular biology and the description of the vessel wall morphology, the aetiology and pathogenesis of GCA are still incompletely understood. Over the years there has been much debate over whether polymyalgia rheumatica and GCA are separate or linked entities. Recent investigations support that polymyalgia rheumatica and GCA are two different expressions of the same underlying vasculitic disorder. A single cause or aetiological agent has not as yet been identified. Except for the histopathology of the arterial wall, there are no laboratory findings specific for GCA, and no particular signs or symptoms specific for the diagnosis. GCA typically causes vasculitis of the extracranial branches of the aorta and spares intracranial vessels. Transmural inflammation of the arteries induces luminal occlusion through intimal hyperplasia. Clinical symptoms reflect end-organ ischaemia. Branches of the external and internal carotid arteries are particularly susceptible. Corticosteroids remain the only proven treatment for GCA, the regimen initially involving high doses followed by a slow taper. However, early detection and treatment with high-dose corticosteroids is effective in preventing visual deterioration in most patients.

Fever of unknown origin: Temporal arteritis presenting with persistent cough and elevated serum ferritin levels

BACKGROUND

Fever of unknown origin (FUO) at the present time is most frequently caused by neoplasm and less commonly by infection. Currently, collagen vascular diseases (CVDs) are an uncommon cause of FUO because most are readily diagnosable by serologic methods and do not remain undiagnosed for sufficient time to present as FUOs. CVDs presenting as FUOs not readily diagnosable with specific tests include late-onset rheumatoid arthritis, adult juvenile rheumatoid arthritis, and polymyalgia rheumatica/temporal arteritis (TA). TA, or giant cell arteritis, is an uncommon arteritis of the mid- and large-sized extracranial arteries of the head and neck and is a rare cause of FUO. TA is characterized by headache, scalp tenderness, jaw pain on chewing, and sudden loss of vision. Fever, anorexia, weight loss, and night sweats may also be present. With TA, respiratory symptoms occur in 9% and are the presenting feature in 4%. Laboratory abnormalities associated with TA include a highly elevated erythrocyte sedimentation rate, anemia, and thrombocytosis, and mildly increased alkaline phosphatase/serum transaminases.

PATIENT

We present a patient with FUO caused by TA whose predominant presenting symptom was persistent cough that overshadowed head and neck symptoms of TA. To the best of our knowledge, this is the first case of TA presenting as an FUO, with a highly elevated serum ferritin level.

RESULTS

We conclude that highly elevated serum ferritin levels in patients with FUO should alert the clinician to consider TA in the differential diagnosis.

IS TEMPORAL ARTERY BIOPSY A WORTHWHILE PROCEDURE?

BACKGROUND

Temporal artery biopsy (TAB) has been accepted as the gold standard for the diagnosis of giant cell arteritis (GCA) or temporal arteritis (TA) even though it is of low sensitivity and specificity. Current medical practice recommends commencing high dose steroids before performing a biopsy, and the continued use of long-term steroids even if biopsy is negative but clinical suspicion of the diagnosis is high. The aim of the present study is to determine if TAB results actually changes the management of patients suspected of GCA or TA.

METHODS

Retrospective case note analysis of 70 consecutive patients with TAB over 5 years (1999-2003) from Royal Melbourne Hospital (RMH), Melbourne, Australia.

RESULTS

Histology revealed five (7%) positive biopsies, five (7%) of 'healed arteritis', and 60 (86%) negative biopsies. After excluding 15 patients who were lost to follow up, management of 13 (23.6%) patients was influenced by the biopsy results: seven with negative biopsies had steroids discontinued while six patients with biopsies showing positive and healed arteritis continued on steroids. Management of 42 (76.4%) patients was not altered following biopsy results: 11 with negative biopsy continued on steroids, 19 never started because of low clinical suspicion and 12 ceased steroids some time after biopsy as there was no symptomatic improvement.

CONCLUSION

With the management of 76.4% of patients unchanged following biopsy, some may argue that these patients underwent unnecessary surgery. However, TAB is a minor procedure that can yield important results for the management of GCA, which if untreated can lead to serious complications. We believe TAB should be performed where there is clinical suspicion of GCA.

Ocular manifestations and concepts of systemic vasculitides

Vasculitic disorders are relatively rare. Their etiology and pathophysiology remain enigmatic, leading to confusing nomenclature and multiple classification schemes. Untreated vasculitis can be fatal. Early diagnosis is the key to successful treatment and better prognosis. However, early diagnosis can be difficult; vasculitic conditions usually present with non-specific symptoms for a long period before clinically overt manifestations occur. Ophthalmologists should be familiar with the ocular manifestations of the vasculitic disorders because they may not only be sight-threatening, but more importantly could be the presenting manifestations of active, potentially lethal systemic disease. This review summarizes clinical and ocular manifestations of systemic vasculitic disorders. Furthermore, it discusses general concepts in diagnosis and treatment of these diseases in an effort to provide a practical framework for the ophthalmologist evaluating patients with vasculitis.

Giant cell arteritis

Giant cell arteritis has been considered an enigmatic disease. It is characterised by chronic granulomatous inflammation of the walls of large and medium-sized arteries. The process has a predilection for the extradural cranial arteries, which include the ophthalmic and the posterior ciliary arteries. It is a multi-symptom disease of older individuals and patients often present with challenging issues and diagnostic dilemmas. We review the literature and latest protocols for the diagnosis and management of giant cell arteritis.

Epidemiology of the vasculitides

In summary, systemic vasculitides constitute a heterogeneous group of overlapping diseases that are somewhat more common than previously considered. Although the causes of vasculitis are largely unknown, epidemiologic studies have implicated geographic, genetic, and environmental factors. Ethnicity, various genes such as those of the MHC, gender, and environmental factors seem to account for the different incidence rates of these syndromes. GCA is the most common vasculitis in elderly people from Western countries. Small-sized cutaneous vasculitides, particularly HSP in children and HV in adults, are also common diseases. Increased physician awareness and the routine use of ANCA tests may contribute to an increase in the recognition of conditions such as WG and MPA.

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 arteritis and sensorineural hearing loss

OBJECTIVES

The association of temporal arteritis and sensorineural hearing loss is a rare occurrence. We present four cases with both these disorders.

METHODS

A 10-year retrospective review of all cases seen at the Geisinger Medical Center showed 271 cases of temporal arteritis and four cases with concomitant sensorineural hearing loss. The four cases were identified, obtained, and extensively reviewed. Patients ranged in age from 59 to 76 years and presented with sensorineural hearing loss and signs, symptoms, and biopsy evidence of temporal arteritis. The response to therapy and clinical course of each case are discussed.

RESULTS

In three patients, the hearing loss preceded the diagnosis of giant cell arteritis by 2 days to 2 months. In one case, the hearing loss was noted concurrently with systemic features of giant cell arteritis. All cases were treated with corticosteroids and had full or partial return of hearing.

CONCLUSIONS

Sensorineural hearing loss can be a preceding or concurrent symptom of temporal arteritis. Recognition and treatment may lead to partial or full recovery. It is not certain whether the time from onset of hearing loss to diagnosis to institution of therapy influences recovery.

Association between strong inflammatory response and low risk of developing visual loss and other cranial ischemic complications in giant cell (temporal) arteritis

OBJECTIVE

To identify clinical and biochemical parameters that have good predictive value for identifying giant cell (temporal) arteritis (GCA) patients who are at high or low risk of developing cranial ischemic events.

METHODS

In this multicenter study, records of patients at 3 university hospitals in Barcelona were reviewed retrospectively. Two hundred consecutive patients with biopsy-proven GCA were studied.

RESULTS

Thirty-two patients developed irreversible cranial ischemic complications. The duration of clinical symptoms before diagnosis was similar in patients with and those without ischemic events. Patients with ischemic complications less frequently had fever (18.8% versus 56.9%) and weight loss (21.9% versus 62%) and more frequently had amaurosis fugax (32.3% versus 6%) and transient diplopia (15.6% versus 3.6%). Patients with ischemic events had lower erythrocyte sedimentation rates (ESR) (82.7 mm/hour versus 104.4 mm/hour) and higher concentrations of hemoglobin (12.2 gm/dl versus 10.9 gm/dl) and albumin (37.4 gm/liter versus 32.7 gm/liter). Clinical inflammatory status and biologic inflammatory status were defined empirically (clinical: fever and weight loss; biologic: ESR > or =85 mm/hour and hemoglobin < 11.0 gm/dl). Patients not showing a clinical and biologic inflammatory response were at high risk of developing ischemic events (odds ratio [OR] 5, 95% confidence interval [95% CI] 2.05-12.2). The risk was greatly reduced among patients with either a clinical (OR 0.177, 95% CI 0.052-0.605) or a biologic (OR 0.226, 95% CI 0.076-0.675) inflammatory reaction. No patient with both a clinical and a biologic response developed ischemic events.

CONCLUSION

The presence of a strong acute-phase response defines a subgroup of patients at very low risk of developing cranial ischemic complications. Our findings provide a rationale for testing less aggressive treatment schedules in these individuals. Conversely, a low inflammatory response and the presence of transient cranial ischemic events provide a high risk of developing irreversible ischemic complications and require a prompt therapeutic intervention.