{'fraction_non_alphanumeric': 0.04822908816880181, 'fraction_numerical': 0.020346646571213264, 'mean_word_length': 4.876106194690266, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Interleukin-33 as a marker of disease activity in rheumatoid factor positive polyarticular juvenile idiopathic arthritis

Abstract Objective: To investigate clinical usefulness of serum interleukin (IL)-33 levels as an indicator of disease activity in juvenile idiopathic arthritis (JIA). Methods: We measured serum levels of IL-33 in 39 patients with JIA, including 7 patients with rheumatoid factor positive poly-JIA (RF + poly-JIA), 8 patients with RF negative poly-JIA (RF-poly-JIA), 20 patients with oligoarticular JIA (Oligo-JIA), 4 patients with enthesitis-related arthritis (ERA) and 30 age-matched healthy controls. Furthermore, we determined their correlation with measures of disease activity. Results: Serum IL-33 levels in patients with RF + poly-JIA were significantly elevated compared to those in patients with RF-poly-JIA, oligo-JIA and HC. Serum IL-33 levels in patients with RF-poly-JIA, oligo-JIA and ERA were not elevated compared to those in HC. Serum IL-33 levels in RF + poly-JIA patients normalized in remission phase. Serum IL-33 levels correlated positively with RF in patients with RF + poly-JIA. Conclusions: These results indicate that serum IL-33 levels in RF + poly-JIA patients correlated with disease activity, suggesting a potential role of IL-33 as a promising indicator of disease activity.