Low cortisol levels in active juvenile idiopathic arthritis

The aim of our study was to evaluate the neuroendocrine system in patients with juvenile idiopathic arthritis (JIA) regarding the activity of disease. Twenty-one JIA patients (mean age ± standard deviation 10.5 ± 4.1 years) were included. None of the patients was taking steroids or antitumor necrosis factor-α therapy during this study. Ten healthy volunteers and ten volunteers with upper respiratory tract infection composed the control groups. Furthermore, ten of the 21 JIA patients were also evaluated during the remission period. Erythrocyte sedimentation rate, C-reactive protein, adrenocorticotropic hormone (ACTH), cortisol, prolactin, insulin-like growth factor-1 (IGF-1), insulin-like growth factor-binding protein 3, free T3, free T4, thyroid-stimulating hormone, interleukin-6 (IL-6) levels, and 24-h urinary cortisol were evaluated both during the active period and remission. The median levels of ACTH and cortisol at 08:00 a.m. were significantly lower in patients with active JIA than patients in remission period and the control groups (p < 0.05). Furthermore, the median level of urine cortisol in active JIA patients was significantly lower than remission period and control groups (p < 0.05). The median level of IGF-1 was significantly lower in active patients than that of remission (p < 0.05). The median level of IL-6 in active JIA patients was significantly higher than those in remission and control groups (p < 0.05). Our preliminary study suggested that impaired secretion of adenohypophyseal hormones and distorted bilateral interactions between the immune and endocrine systems in JIA. Further studies are needed to clarify the consequences of the impaired hormone secretion in JIA.