Background Neopterin is a molecule produced by monocytes by stimulation of Interferon Gamma. It is elevated in infections, autoimmune diseases, malignancies, transplant rejection, neurodegenerative, and cardiovascular conditions such as pregnancy [1,2].

Objectives To investigate the serum levels of neopterin in patients with early arthritis (EA) and establish its relationship with activity disease.

Methods Non-experimental, prospective and longitudinal study was conducted in patients with EA (<2 years of evolution) and >18 years of age. On days 0, 6 and 12 months physical examination and analysis of parameters of activity within 7 days of the blood sample (DAS28, HAQ, EVA and ESR, CRP, FR, anti-CCP and ANA) were performed. Neopterin determination was made by ELISA reagent kit Gen Way Biotech Inc and calculated with Logit-log. Normal value below 10 nmol/l was considered.

Radiographs of hands and feet at the initial visit and 12 months through SENS method (score of grips and erosions) were evaluated.

Neopterin values were compared to a control population of 47 healthy individuals. Stata 9.0 for data analysis. Fisher 2 to chi-2.

Results Twenty-seven patients (36±13 years), 19 (70%) women and 8 (30%) males were evaluated. At first the mean value of neopterin in EA Group was 7.51 (5.5–11.4) vs 5.32 (3.5–6.44) in the control grou p (p=0.0004). It was correlated with scores of activity, and the activity measured by DAS28 was observed that in the initial period: Neopterin >10 nmol/L (n=8): 3.37 [2.53–4.36] vs Neopterin standard value (n=19): 3.86 [3.24 -4.54] (p=0.34).At 6 months: Neopterin>10 (n=5): 3.33 [2.14–4.33] vs Neopterin standard (n=22): 2.96 [2.66–3.73] (p=0.6); and at 12 months: Neopterin >10 (n=9): 3.08 [2.49–3.79] vs Neopterin standard (n=18): 2.90 [2.34–3.27] p=0.53. No correlation was found between neopterin and DAS 28.

Conclusions In this study the results showed no correlation between disease activity (DAS28) and high concentrations of serological marker (neopterin) compared in the three periods or with other international assessment rates. Correlation was observed between DAS 28 and acute phase reactants (ERS and CRP) in the three periods. It would require studies with more patients to confirm these data.

1. Machold KP, Smolen JS. J Rheumatol. 2002; 29: 2278- 2287.

2. Neopterin as a Marker for Immune System Activation. Current Drug Metabolism, 2002, 3, 175–187. Noninvasive monitoring using serum amyloid A and serum neopterin in cardiac transplantation. Clin. Chim. Acta 1998; 276:63–74.

Disclosure of Interest None declared