Serum TNF-alpha levels correlate with disease severity and are reduced by effective therapy in plaque-type psoriasis

TNF-alpha is a pleiotropic cytokine possibly involved in the pathogenesis of psoriasis.

to analyze the serum TNF-alpha levels in plaque-type psoriatic patients to evaluate the concentrations, correlation with the severity score and behaviour after therapy. The serum TNF-alpha levels of thirty-seven patients (25 females and 12 males; median age: 52.5 years, range 18-81: median PASI score: 11.4, range 3.5-42) and thirty healthy controls (21 females and 9 males, median age: 48.5 years, range 25-77) were compared after measurements obtained employing commercially available ELISA kits. The median serum TNF-alpha levels of the patients were significantly higher than those of controls (p = 0.004). 30/37 patients were followed over time at 2 and 4 weeks of treatment. Twenty one subjects were also observed after 6 weeks. After effective treatments, both the PASI scores and the cytokine levels were significantly and concomitantly reduced (p < 0.001). Significant correlations were found when the TNF-alpha values were plotted against the PASI scores both at the time of patient enrollment and at all the subsequent times (118 observations). A significant correlation was observed between circulating TNF-alpha and sE-selectin in agreement with a possible functional activity of the cytokine. However, no correlation was found between the cytokine levels and other 4 soluble membrane molecules. Our findings indicate that the molecule studied, although non specific for the disease considered, presents a behaviour paralleling that of the disease severity and therefore might have clinical usefulness, particularly in monitoring the therapeutic effects.