Serum melatonin in juvenile rheumatoid arthritis : correlation with disease activi

الملخص EN

Objective : to investigate the abnormalities in early morning serum melatonin among patients with juvenile rheumatoid arthritis (JRA) and to outline its relation to disease activity and severity.

Methodology : Twenty one patients with JRA and twenty healthy age and sex matched controls were enrolled in the study.

Fifteen patients had polyarticular JRA, 3 had oligoarticular JRA and 3 had systemic onset JRA.

Evaluation was carried out clinically, functionally and radio logically by using disease activity score, Juvenile Arthritis Functional Assessment Report for Children (JAFAR-C score) and modified Larsen score respectively.

Laboratory investigations included CBC, ESR, CRP, classic IgM RF (latex agglutination), ANA (indirect immunofluorescence) and melatonin estimation by Enzyme Linked Immunosorbent Assay (ELISA).

Results : the serum levels of melatonin were significantly increased in JRA patients (13.9 ± 8 pg /ml) as compared to healthy controls (8.1 ± 2.7 pg /ml) (p < 0.01).

A significant positive correlation could link serum melatonin levels to disease activity scores and ESR (r = 0.91, p < 0.001 and r = 0.55, p < 0.01 respectively).

No significant correlation was found between melatonin and either Larsen or JAFAR scores (r = 0.19, p > 0.05, r = 0.15, p > 0.05 respectively).

According to melatonin levels, there was 2 groups of patients: group 1 with elevated melatonin level (more than 11 pg / ml) (n = 15) and group 2 with normal melatonin level (less than 11 pg / ml) (n = 6).

Patients with elevated melatonin levels had higher ESR (p < 0.05), higher disease activity scores (p < 0.01) and Larsen scores (p < 0.05), than the group of patients with normal serum melatonin.

The results of GAFAR scores were comparable between the two groups (p > 0.05) Conclusion : the elevated melatonin levels among JRA patients with active sinusitis and its close relation to disease activity rather than disease severity suggests that melatonin may play a promoting role in rheumatoid arthritis.

Hence, inhibition of its synthesis and / or action by specific antagonists may be of therapeutic value.

Serum Melatonin in Juvenile Rheumatoid Arthritis : correlation with Disease Activity.