A multicenter study of clinical and laboratory findings of palindromic rheumatism in Iran.

OBJECTIVE: Considering demographic, clinical and laboratory characteristics of palindromic rheumatism and finding out the difference between rheumatoid factor and anti-cyclic citrullinated peptide positive and negative cases of palindromic rheumatism in Iran.
METHODS: In this cross-sectional and multicenter study, patients with intermittent arthritis were evaluated by a rheumatologist for palindromic rheumatism. Diagnosis of palindromic rheumatism was made after ruling out other causes of recurrent arthritis, and the fulfillment of the Pasero and Barbieri criteria. Then the demographic and clinical characteristics were recorded and compared in rheumatoid factor and anti-cyclic citrullinated peptide positive and negative patients.
RESULTS: Of the 69 patients with palindromic rheumatism, 35 were men and 34 were women. The mean ages of the patients at the time of diagnosis were 38.5 ± 14.6 years. The mean attack intervals and duration of the attacks were 66.3 ± 38.4 days and 3.9 ± 3.3 days, respectively. The most commonly involved joints were knees, metacarpophalangeals and proximal interphalangeals. Rheumatoid factor in 46.4% and anti-cyclic citrullinated peptide in 42% of the cases were positive. Palindromic patients with positive anti-cyclic citrullinated peptide had higher age, shorter duration of disease, shorter duration of attacks, more frequent attacks and more metacarpophalangeal joints involvement.
CONCLUSIONS: Rheumatoid factor and anti-cyclic citrullinated peptides were found in a high proportion of patients with palindromic rheumatism. The clinical features of the disease in our study were different in rheumatoid factor and anti-cyclic citrullinated peptide positive and negative patients.