Distinguishing patients with active systemic lupus erythematosus (SLE) from those
with inactive disease has always been considered a great challenge. Identifying new
sensitive markers of activity will be of great value in the clinical management of the
disease. Thus the aim of the current study was to investigate the relationship between
serum neopterin levels and various parameters of disease activity currently used, in
addition, to investigate serum neopterin levels in different patterns of organ disease
involvement and during the administration of different therapy regimens used in the
management of SLE. The study was conducted on 75 female subjects; 26 patients with
active SLE, 24 SLE patients in remission and 25 healthy controls. Patients with SLE
were fulfilled four or more of the American Rheumatism Association (ARA) criteria,
and disease activity was scoredusing the British Isles Lupus Assessment Group
(BILAG) index.Erythrocyte sedimentation rate (ESR), serum urea, serum creatinine,
liver function tests, plasma complements C3 and C4, C3 degradation products
(C3dg), anti-double stranded DNA antibodies (anti-dsDNA) and serum neopterin
were measuredin all groups. Serum neopterin was significantly elevated in the active
group as compared to the remission group.Both groups of SLE showed higher levels
of neopterin when compared to the control group. Serum neopterin level showed
higher sensitivity than other SLE markers (80%) and second highest specificity after
anti-dsDNA antibodies (73%). Also, a highly significant positive correlation was
found between serum neopterin levels and each of plasma C3dg, anti-dsDNA
antibodies, and ESR. Meanwhile, a highly significant negative correlation was
detected between serum neopterin levels and both plasma C3 and C4 levels. As
regarding various treatment regimens used in the management of active SLE, the
current study demonstrated decrease in serum neopterin levels in patients receiving
combined treatment of both prednisolone and cytotoxic drugs than those receiving
either treatment alone. A significant difference in serum neopterin levels was
observed in patients with multiple organ affection in comparison to those with single
organ affection regardless the type of organ affected. The present results suggest that
the estimation of serum neopterin levels seems beneficial in the assessment of disease
activity and progress in SLE patients as well as the assessment of the efficacy of
various treatment regimens being used.