Generalized Rheumatism: Polymyalgia Rheumatica and its Differential Diagnosis

Peripheral Musculoskeletal Manifestations in Polymyalgia Rheumatica

OBJECTIVES

The objectives of this study were to evaluate the frequency and characteristics of the peripheral musculoskeletal manifestations in polymyalgia rheumatica (PMR), evaluate if PMR with peripheral synovitis represents a subset with a more severe disease, and examine for clinical and laboratory characteristics at onset of PMR that might later predict rheumatoid arthritis (RA).

PATIENTS AND METHODS

Patients were diagnosed with PMR according to the 1982 Chuang criteria. Patients were followed up between 1990 and 2002. The following musculoskeletal manifestations at onset and during the follow up were considered: peripheral synovitis, distal extremity swelling with pitting edema, carpal tunnel syndrome, and distal tenosynovitis.

RESULTS

Thirty-eight of the 74 patients (51%) showed distal musculoskeletal symptoms: 29 (39%) had peripheral synovitis, 4 (5%) presented pitting edema, 4 (5%) experienced carpal tunnel syndrome, and one (1.3%) had distal tenosynovitis. These manifestations resolved completely after corticosteroid therapy was initiated. Peripheral synovitis was oligoarticular and often transient. The joints most frequently involved were the wrist, metacarpophalangeal, and knee. Erythrocyte sedimentation rate (ESR) was normal in 7 patients. When comparing patients with PMR with and without peripheral synovitis, no statistically significant differences were found in the studied variables. Through the first year of follow up, 7 patients fulfilled the American College of Rheumatology 1987 criteria for RA, 2 patients developed giant cell arteritis, and 3 had associated malignancy. Patients who developed RA had statistically significantly increased presence of persistent synovitis and a smaller decrease in mean ESR after treatment with corticosteroids.

CONCLUSION

Fifty-one percent of the patients with PMR presented distal musculoskeletal manifestations, with peripheral synovitis being the most frequent one. Patients with PMR with peripheral synovitis did not represent a high-risk subgroup with more severe disease. Seven patients who developed criteria for seronegative RA within the first year of follow up had presented statistically significant persistent synovitis compared with those who continued as PMR and also showed a smaller initial decrease in mean ESR after steroid treatment was initiated. The absence of persistent arthritis and the benign course of the arthritis permit the distinction of PMR from other inflammatory arthropathies.

Treatment of polymyalgia rheumatica/giant cell arteritis

Corticosteroids control arteritis in GCA and suppress polymyalgic symptoms within days of starting treatment. PMR patients can be treated with approximately 15 mg prednisolone/day, reducing the dose to 7.5-10 mg by 8 weeks. GCA is normally controlled on 40 mg prednisolone/day, although patients with persistent visual symptoms may need 60-80 mg. Slow reduction to about 20 mg by 8 weeks should minimize relapses. For both PMR and GCA a maintenance dose of 7.5 mg after 6-9 months should be enough. Steroid withdrawal is possible within 2 years of starting treatment, although some will need 4 years or more. Relapse should be defined clinically; the ESR is the most useful laboratory parameter. Steroid side-effects can be minimized by using low doses of prednisolone whenever possible and azathioprine may be used as a steroid-sparing agent.

Treatment of polymyalgia rheumatica and giant cell arteritis. I. Steroid regimens in the first two months

Thirty nine patients with polymyalgia rheumatica (PMR) and 35 with giant cell arteritis (GCA) were treated with high or low dose steroid regimens in a prospective study of the first two months of treatment. Patients with PMR needed 15-20 mg prednisolone initially; 13/20 (65%) relapsed on an initial dose of 10 mg/day. All but two patients with GCA were successfully treated with 40 mg/day prednisolone initially but relapsed on a reduction to 20 mg/day. One patient with GCA receiving 30 mg/day relapsed after four weeks. Six patients with PMR developed GCA during the first two months and required an increased prednisolone dose to control symptoms. The erythrocyte sedimentation rate or C reactive protein did not predict relapse.

Polymyalgia rheumatica and corticosteroids: how much for how long?

In a prospective study of 176 patients in whom polymyalgia rheumatica (PMR) or giant cell arteritis (GCA) had been diagnosed between 1968 and 1980 the effect of corticosteroid treatment was studied. In those with PMR alone an initial regimen of 10 mg prednisolone daily and for the majority of those with GCA 20 mg daily were adequate to control symptoms. No patient suffered a serious disease complication after starting treatment. Regular follow-up enabled the minimum effective corticosteroid dose to be used. Complications of treatment were infrequent. Corticosteroid treatment has been withdrawn from 72 patients after a mean of 31 months treatment (range 3-103 months). Thirty subsequently relapsed, all within 21 months of withdrawal. No clinical feature predicted those who were more likely to relapse. No rigid treatment schedule should be used in these diseases.

Strathpeffer Spa: Dr William Bruce and polymyalgia rheumatica

The first description of polymyalgia rheumatica is attributed to Dr William Bruce working in Strathpeffer Spa, Scotland, in 1888. His career, the history of the spa, and the original article are briefly described.