RS3PE revisited: a systematic review and meta-analysis of 331 cases.

Objectives: Remitting seronegative symmetrical synovitis with pitting oedema (RS(3)PE) syndrome is a rare inflammatory arthritis, characterised by symmetrical distal synovitis, pitting oedema of the hands and feet, absence of rheumatoid factor, and favourable response to glucocorticoids. The aim of our study is to further delineate the clinical and laboratory features, and response to treatment.

Methods: We performed a systematic electronic search of Medline, PubMed, EMBASE, ACR and EULAR databases for case reports, case series, and related articles of RS(3)PE. Statistical analysis was done comparing categorical variables with Chi-square tests and frequencies of means via t-tests. Binary logistic regression analysis was performed to identify predictors of erosions, recurrence, malignancy and rheumatologic disorders.

Results: 331 cases of RS(3)PE were identified from 121 articles. RS(3)PE was found in older patients (71±10.42 years) predominantly in males (n= 211, 63.36%), was symmetrical (n=297/311, 95.50%) involved the hands (n=294/311, 94.53%) A concurrent rheumatologic condition was reported in 22 cases (6.65%), and malignancy in 54 cases (16.31%). Radiographic joint erosions were found in 5.5%. Most patients responded to medium-dose glucocorticoids (16.12±9.5 mg/day). Patients with concurrent malignancy requiring non-significantly higher doses of prednisone (18.12 vs. 15.76 mg, p 0.304) and higher likelihood of recurrence of disease (OR 4.04, 95% CI 1.10-14.88, p=0.03).

Conclusions: The symptoms and unique findings that make up RS(3)PE appear to represent a steroid-responsive disease that may be a harbinger of an underlying malignancy. More study is needed to understand the molecular origins of RS(3)PE in order to determine whether it is a separate disease process. Patients with concurrent cancer tend to have more severe presentations and higher rates of recurrence.