Background: The RS3PE syndrome is a recently described uncommon disorder in the elderly patient; in the initial reports, it was characterized by an excellent prognosis with total remission. In contrast with rheumatoid arthritis and polymyalgia rheumatic, it has been related to HLA B7. Further works have questioned its benign nature and even that it is a new entity. Our objective was to study the clinico-biological characteristics, therapy, and clinical course in patients with RS3PE attended at our clinic.
Methods: Retrospective descriptional study of patients with RS3PE attended in our clinic from January 1992 to December 1998 following the inclusion criteria proposed by Olivé et al. For all patients, the following determinations and studies were performed: complete blood count, ESR, serum biochemistry, two measurements of rheumatoid factor (RF), and X-ray. Class I HLA typing was determined in five cases.
Results: Eight patients were found (6 men and 2 women), with a mean age of 68.7 years. The arthritis was more common at MCP, wrists, shoulder, and PIF in hands. Four patients had tenosynovitis of the hand flexors. ESR (mean: 69.3) and RCP (mean: 49.7) were increased in most cases. Seven patients had leukocytosis. HLA B7 was positive for 4 out of five patients. All patients were treated with low-dose corticosteroids, with a mean length of 9.5 months. Three patients had relapses. During follow-up after therapy had been completed, none of the patients had other diseases.
Conclusions: RS3PE syndrome involves elderly patients and its clinical course is characterized by sudden onset seronegative symmetrical polysynovitis, with pitting edema over the hand dorsum and less commonly over the pretibial region. In most cases, a marked acute-phase reaction and leukocytosis were observed. Therapy with low-dose corticosteroids is effective; sometimes however, it is necessary to add antimalarial agents. The three patients who relapsed had underlying diseases: chronic lymphocytic leukemia, Sjögren's syndrome, and liver cirrhosis, respectively. The diagnosis of RS3PE should be obtained a posteriori, after a prolonged follow-up of the patient. Atypical cases, with evolution towards other rheumatic or hematological disorders or as paraneoplastic manifestation, have been reported.