Pathogenesis and clinical manifestations of juvenile rheumatoid arthritis / 소아과

Juvenile rheumatoid arthritis (JRA) is the most common rheumatic childhood disease; its onset is before 16 years of age and it persists for at least 6 weeks. JRA encompasses a heterogeneous group of diseases that is classified according to 3 major presentations: oligoarthritis, polyarthritis, and systemic onset diseases. These presentations may originate from the same or different causes that involve interaction with specific immunogenetic predispositions, and result in heterogeneous clinical manifestations. An arthritic joint exhibits cardinal signs of joint inflammation, such as swelling, pain, heat, and loss of function; any joint can be arthritic, but large joints are more frequently affected. Extra-articular manifestations include high fever, skin rash, serositis, and uveitis. The first 2 types of JRA are regarded as T helper 1 (Th1) cell-mediated inflammatory disorders, mainly based on the abundance of activated Th1 cells in the inflamed synovium and the pathogenetic role of proinflammatory cytokines that are mainly produced by Th1 cell-stimulated monocytes. In contrast, the pathogenesis of systemic onset disease differs from that of other types of JRA in several respects, including the lack of association with human leukocyte antigen type and the absence of autoantibodies or autoreactive T cells. Although the precise mechanism that leads to JRA remains unclear, proinflammatory cytokines are thought to be responsible for at least part of the clinical symptoms in all JRA types. The effectiveness of biologic therapy in blocking the action of these cytokines in JRA patients provides strong evidence that they play a fundamental role in JRA inflammation.

The Correlation between Increased Sensitization Rate to Weeds in Children and the Annual Increase in Weed Pollen in Korea / 소아알레르기및호흡기학회지

PURPOSE: Recently allergic diseases have gradually increased in schools and among preschool aged childhood. Pollen amount of weeds also, especially ragweed, were increased. We evaluated the increased pollen count of weed was associated with the sensitization rate to weed in childhood. METHODS: Airborne particles carrying allergens were collected daily from eight stations nationwide(Seoul, Guri, Cheongju, Daegu, Kwangju, Busan, Kangneung, and Jeju) by using 7 days-Burkard sampler(Burkard Manufacturing Co Ltd, Hertfordshire, UK), for 7 years in South Korea(July 1, 1997-June 30, 2004). They were counted and recorded along with the weather. Data was collected through pediatric patients with allergic symptoms, who visit the pediatrics allergy clinics and capable of allerfy skin test among hospitals that have pollen collecting centers. RESULTS: Airborne pollen has two peak seasons:May and September in Korea. There were the tree pollen seasons from the middle of February to late July, then followed the grasses and weed season from the middle of July to the end of October. Ragweed was one of the most common pollens of autumn in Korea. In skin prick tests, Mugwort was the highest sensitization rate(7.6 percent), followed by ragweed(7.1 percent), birch(6.1 percent), alder, grasses mix among the pollen extracts in Korean school aged children. Ragweed pollen counts have gradually increased since 2000. In the same period, sensitization rates for airborne pollen, especially weeds, in Korean children have increased annually(1999:4.4 percent, 2000:7.1 percent, 2001:7.4 percent, 2002:8.5 percent, 2003:7.7 percent). CONCLUSION: Sensitization rates for outdoor airborne pollens have increased in Korean children. These findings might result from the changes of life styles and living environments in Korea.