Changes of Platelet Indices in Juvenile Idiopathic Arthritis in Acute Phase and After Two Months Treatment

Background: Various indices have been raised as predictors of activity and severity of juvenile idiopathic arthritis.
Objectives: This study was conducted to investigate the changes of platelet indices in acute phase and two months after treatment in these patients.
Patients and Methods: In a cohort study, platelet count, mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT) were evaluated in children referred to children’s medical center, Tehran due to juvenile idiopathic arthritis from March 2013 to March 2014 during the acute phase and two months after standard treatment. The statistical data were analyzed by SPSS 19 software, and the significance level was set as P < 0.05.
Results: In this study, 55 children (24 boys and 31 girls) with meanSD age of 7.50 ± 3.35 years were studied. The meanSD value of platelet count was 441872.7 ± 151836.9 in the acute phase and reached 395418.2 ± 119601.6 two months after treatment (P = 0.01). The meanSD PCT in the acute phase of various subtypes of the disease was 0.32 ± 0.11, which reached 0.29 ± 0.10 after treatment (P = 0.09). However, the PDW range in different subtypes of the disease reached 13.4 ± 8.0 from 13.9 ± 2.9 and MPV reached 8.7 ± 0.9 from 8.8 ± 1.1 after treatment, but they were not significantly different from the results in the acute phase (P = 0.5).
Conclusions: Platelet count is one of the most remarkable indices in JIA. Evaluation of PCT can also help determine the severity of the inflammatory process in the follow-up and treatment process.

Keywords
Juvenile Idiopathic Arthritis; Acute Phase Reactants; Platelet Count; Platelet Indices; Mean Platelet Volume