The use of dapsone in the treatment of giant cell arteritis and polymyalgia rheumatica

Steroid-sparing effect and toxicity of dapsone treatment in giant cell arteritis: A single-center, retrospective study of 70 patients

Although a glucocorticoid (GC)-sparing strategy is needed for patients with giant cell arteritis (GCA) suffering from refractory disease or serious treatment-related complications, evidence of efficacy in this setting of immunosuppressive drugs and biotherapies is lacking. Herein, we evaluated the GC-sparing effects and tolerability of addition of dapsone (DDS) to prednisone therapy in patients with GCA. We retrospectively assessed data on 18 GCA patients who received DDS as a first-line treatment (DDS-1 group) and 52 patients who received it as a second- or third-line treatment for refractory GCA, with or without excessive GC-related toxicity (DDS-2 group). Of these 70 patients, 63 belonged to an inception cohort of 478 patients, whereas the remaining 7 were referred to our department for resistant GCA. In all, 52 patients were assessable for DDS efficacy. The baseline characteristics of the DDS-1 patients were similar to those of 395 GCA patients (control group) who received prednisone alone. DDS-1 patients had a more sustained decrease in GC dose with a lower mean prednisone dose at 12 months, and they comprised higher proportions who achieved GC withdrawal within the first year, who stopped prednisone treatment, and who recovered from GCA (P < 0.001 for each variable). Patients in the DDS-2 group achieved a mean rate of prednisone reduction of 65% and a prednisone dose reduction of 16.9 ± 13.3 mg/d. The monthly decreases in the prednisone dose were 2.4 and 1.25 mg in DDS-1 and DDS-2 patients, respectively. DDS-induced side effects were recorded in 44 (64%) assessable patients. These side effects led to lowering of the DDS dose by 25 mg/d in 11 (16%) patients and permanent cessation of DDS in 14 patients (20%), due to allergic skin rash in 7, agranulocytosis in 2, icteric hepatitis in 2, and excessive hemolysis in 2 patients. DDS is a potent GC-sparing agent in GCA that should be evaluated in prospective studies. However, DDS use should be restricted to refractory GCA patients due to its toxicity, and close clinical and laboratory monitoring for 3 months is necessary.

Giant cell arteritis: an updated review

Giant cell arteritis (GCA) is the most common primary vasculitis of adults. The incidence of this disease is practically nil in the population under the age of 50 years, then rises dramatically with each passing decade. The median age of onset of the disease is about 75 years. As the ageing population expands, it is increasingly important for ophthalmologists to be familiar with GCA and its various manifestations, ophthalmic and non-ophthalmic. A heightened awareness of this condition can avoid delays in diagnosis and treatment. It is well known that prompt initiation of steroids remains the most effective means for preventing potentially devastating ischaemic complications. This review summarizes the current concepts regarding the immunopathogenetic pathways that lead to arteritis and the major phenotypic subtypes of GCA with emphasis on large vessel vasculitis, novel modalities for disease detection and investigative trials using alternative, non-steroid therapies.

Novel therapeutic strategies for large vessel vasculitis

Giant cell arteritis and Takayasu's arteritis are systemic vasculitides that cause inflammation of large arteries and their branches. Both have similar histology, but differ in their age of onset. Corticosteroids have been the mainstay of treatment for the past 50 years but are limited by the potential toxicity that may occur in almost 60% of patients. This limitation has lead to the investigation of alternative agents for the treatment of these diseases.

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.

Update on giant cell arteritis

PURPOSE OF REVIEW

Giant cell arteritis (GCA) is the most common form of systemic vasculitis that causes visual loss in the elderly. This review highlights current concepts dealing with the diagnosis, treatment, and visual prognosis of patients with GCA.

RECENT FINDINGS

Recent evidence suggests that recovery of visual function in patients with visual loss from GCA is poor. An algorithm has been constructed to assist clinicians in the evaluation and management of patients suspected of having GCA.

SUMMARY

Despite a number of new adjunctive agents, corticosteroids remain the standard treatment in patients with GCA.

Polymyalgia rheumatica/temporal arteritis: recent advances

Polymyalgia rheumatica (PMR)/temporal arteritis (TA) frequently causes significant morbidity in patients older than 50 years of age. This review highlights recent trends in clinical findings, epidemiology, pathogenesis, and laboratory and radiologic assessment of the disease. Although steroids are the mainstay of therapy because of their effectiveness and ease of administration, they have numerous side effects, particularly in an aging population. Furthermore, recent evidence suggests that steroids only suppress clinical symptoms, while a smoldering level of damaging vascular inflammation persists. As a result, alternative agents are actively being investigated. We compare their successes and shortcomings and offer insight into their potential role in the treatment of this disease.

Novel therapies in vasculitis

The vasculitides comprise various clinical and pathological entities which pose a therapeutic challenge in terms of disease control versus drug toxicity. Glucocorticoids are important in most regimens; duration of exposure and dosages can be minimised by the use of cytotoxic drugs and transplant immunosuppressives such as cyclosporin, tacrolimus and mycophenolate mofetil. Among alkylating agents, cyclophosphamide has proven to be highly effective; switching to less toxic antimetabolites, typically methotrexate, for maintenance after achieving disease control is an effective strategy. Plasmapheresis may be considered when pharmacological options are maximised. IVIG infusions are of proven benefit in Kawasaki disease and possible benefit in other vasculitides. Targeting infective aetiologies is the basis of therapies such as lamivudine and vidarabine for hepatitis B associated polyarteritis nodosa as well as ribavarin and IFN-alpha for hepatitis C associated cryoglobinaemic vasculitis. IFN-alpha also has immunomodulatory effect even in non-hepatitis C-associated vasculitis. Trimethoprim-sulphamethoxazole has been used in limited Wegener's granulomatosis. Thalidomide, colchicine and dapsone are miscellaneous agents that have been used in Behcet's disease and cutaneous vasculitis. Anti-lymphocytic monoclonal antibodies have been employed for induction therapy in Wegener's granulomatosis. The tumour necrosis factor inhibitor etanercept is just being explored as a therapeutic agent. Bone marrow and stem cell transplantation may find a role in refractory disease.

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.

Methotrexate use in systemic vasculitis

Although GS and CYC have been important agents in improving the outcome and survival of patients with systemic vasculitis, they carry their own risk of drug-induced morbidity and mortality. It has also become apparent that these medications are not the final answer in disease management because some forms of vasculitis have the potential to relapse or be treatment resistant. For these reasons, the pursuit of effective, less toxic therapeutic alternatives is critical. Initial results from the use of MTX in systemic vasculitis have been encouraging. Although drug-related toxicity and disease relapse have still been found to occur, MTX appears to be a valuable addition in the treatment of vasculitis. Further studies will be necessary to determine the optimal way that this agent may be used to safely and effectively manage vasculitic disease.

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.

Steroid-sparing medications in temporal arteritis--report of three cases and review of 174 reported patients

More than half the patients with temporal arteritis experience steroid-related side effects, which are associated with increased morbidity and may shorten life expectancy. We describe 3 such patients, and our experience in tapering their steroid dosage with the use of dapsone or methotrexate. Based on our data and the review of 174 reported patients, it seems that no definite recommendation can be drawn regarding the use of steroid-sparing agents in temporal arteritis. There is a need for large controlled studies of several potential agents to evaluate their role in the treatment of this disease.

Methotrexate treatment in the management of giant cell arteritis

Eleven newly-diagnosed GCA patients were included in a prospective open study and treated with high initial prednisone doses, a quick-tapering CS schedule and weekly oral MTX for two years. It took a mean of 14 weeks to reach a 10 mg/day dose of prednisone and 29.8 weeks until steroid withdrawal. The mean cumulative dose of prednisone was 3.4 g. Two patients relapsed and five developed CS side effects. No serious MTX side effects were observed. Our results suggest that MTX is safe and could be useful in the therapy of GCA.