Analytic Study of the Clinical Features of Korean Juvenile Rheumatoid Arthritis (JRA)

Oh, Kwan Taek; Jung, Sung Soo; Yoo, Tae Seok; Lee, Je Kyung; Song, Yong Ho; Jun, Ja Hun; Koh, Hee Kwan; Kim, Tae Hwan; Jun, Jae Bum; Lee, In Hong; Bae, Sang Cheol

Abstract

OBJECTIVE
To investigate the clinical characteristics of Korean JRA and the possible profiles related to prognosis and to compare these data to pre-existing occidental reports.
METHODS
140 cases of JRA patients were randomly selected from 1986 through 1995. Juvenile ankylosing spondylitis was excluded with the aid of modified New York criteria for ankylosing spondylitis. We used the classification of progression of rheumatoid arthritis (radiological stage III+IV / I+II+III+IV) as a index of prognosis. The study factors were sex, age, type, affected joints, degree of destruction of joint, anti-nuclear antibody (ANA), rheumatoid factor (RF), HLA-B27 and extra-articular manifestations. Chi-square test, One-way ANOVA test, and Pearson' s correlation coefficient were used as statistical methods.
RESULTS
Our study show results as follows : (1) Systemic onset type (ll%) { polyarthritis subset (66%), oligoarthritis subset (34%) }, oligoarthritis onset type (62%) { sero (-) -HLA-B27 (+) subset (66%) , RF (+) subset (20%), not otherwise classified subset (14%) ANA(+)-chronic uveitis subset(O%) }, polyarthritis onset type (27%) { RF(+) subset (66%), not otherwise classified subset (34%) }, (2) Sex ratio was M:F=1.8:l. (3) Age of onset was 11+3.6 years. (4) Affected joints were knee, ankle, hand in decreasing order of frequency. (5) Patients show seropositivity of RF in 31%, HLA-B27 in 54%, ANA in 8%. (6) Chronic uveitis was observed in 7 cases (5%) (all oligoarthritis onset type, M:F=6:1, age of onset 11+4.3 years, ANA (0%), HLA-B27 (86%) , 2 cases leading to blindness. (7) Destructive bone change was significantly more prominent in female (p<0.01) , RF(+) (p<0.01), HLA-B27(-) (p<0.01) , polyarthritis onset type (p=0.02).
CONCLUSIONS
In this study, we obtained interesting results that are somewhat different from Occidental data in sex ratio (male dominance), age of onset (older age) , profiles of HLA-B27 (high positivity in spite of low HLA-B27 positivity in Korean (about 2. 3%) , low rate of destructive change) , ANA (low positivity, older age of onset) , chronic uveitis (low incidence, male dominance, older age of onset, high association with HLA-B27, not associated with ANA) . This study suggests possible racial difference in clinical features of JRA. But for prove of racial difference, further multi-center trial and large scale epidemiological study should be done.