T-helper lymphocyte subsets and T cell activation in peripheral blood of children with juvenile idiopathic arthritis and arthralgias caused by other conditions

Abstract

Introduction: Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in children. It encompasses a group of clinically heterogeneous arthritides that begin before the age of 16, and persist for more than 6 weeks.  JIA often begins with pain in a joint and febrile condition, therefore it's very important to distinguish it from diseases with similar presentations.

Aim of this study was to examine and determine T-helper lymphocyte subsets CD4+CD45RA+, CD4+CD45RO+ and  activated T-cells in peripheral blood of children with JIA and arthralgias caused by other conditions.

Patients and methods: Retrospective study included 40 patients with JIA and 40 patients with arthralgias caused by other conditions. Lymphocytes quantification was performed with Beckman-Coulter FC-500 cytometer.

Results: There was no statistical difference in the percentage of T-helper lymphocytes  between children with JIA and children with arthralgias caused by other conditions (36.3±9.1:39.2±7.8; p>0,05). Also, percentage of CD4+CD45RA+ T-lymphocytes  (20.5±8.3:23.2±7.2; p>0,05), and CD4+CD45RO+ T-lymphocytes were not different between two examined groups (15.7±4.9:15.9 ± 6.0;  p>0,05).

Decrease in the ratio of CD4+CD45RA+T/CD4+CD45RO+T in patients with JIA in comparison with those in children with arthralgias caused by other conditions is significant     (15:6; p=0,04). Concerning T-cell activation, measured as HLA DR expression, we find significant difference between children with JIA and children with arthralgias caused by other conditions (2.04±0.8:1.6±0.7;  p=0,01).

Conclusion: Although there are clinical similarities between the JIA and arthritides caused by other reasons those two entities appear to be distinct phenotypically in expression of CD45 isoforms on T-helper lymphocytes and proportion of activated T-cells.