Correlation of mean platelet volume, neutrophil-to-lymphocyte ratio, and disease activity in children with juvenile ıdiopathic arthritis.

Juvenile idiopathic arthritis (JIA) is a chronic inflammatory arthritis characterized by periods of remission and relapse. Mean platelet volume (MPV) is an indicator of systemic inflammation. In the present study, we aimed to determine the association between mean platelet volume (MPV), neutrophil/lymphocyte ratio (NLR), platelet distribution width (PDW) and clinical measures of diseases activity in children with JIA. The study included 115 patients with JIA (64 with active disease and 51 with inactive disease) and 64 age-gender matched healthy control subjects. Routine laboratory methods were used to measure white blood cell count (WBC), platelet count (PLT), neutrophil count, lymphocyte count, hemoglobin (Hb), MPV, PDW, NLR, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in all subjects of both the patient and control groups. Active disease was associated with significantly increased MPV (8.23 ± 1.16 fl) compared with inactive disease (7.00 ± 1. 08 fl) and control subjects (6.77 ± 1.08 fl) P<0.001, P<0.001, P=NS, respectively). NLR was significantly higher in patients with active (2.11 ± 1.19) and inactive (2.03 ± 1.51) disease relative to the control subjects (1.33 ± 0.66) (P<0.001, P=0.017, respectively). Mean PDW was significantly higher in patients with active disease (17.84 ± 1.06) compared with the control group (17.19 ± 0.93) (P=0.01). Our results suggest that MPV may be a useful marker of disease activity in patients with JIA. Regular treatment may decrease platelet activation in JIA patients. However, NLR was not a predictive marker of disease activity in patients with JIA.