A double-blind, randomized, placebo-controlled trial of n-3 fatty acid based lipid infusion in acute, extended guttate psoriasis. Rapid improvement of clinical manifestations and changes in neutrophil leukotriene profile.
Twenty patients hospitalized for acute psoriasis guttata with a minimum 10% of body surface area involvement (range 10-90%) completed a 10-day trial in which they were randomly allocated to receive daily infusions with either an n-3 fatty acid based lipid emulsion [100 ml/day with 2.1 g eicosapentaenoic (EPA) and 21 g docosahexaenoic acid (DHA)] or a conventional n-6 lipid emulsion (EPA + DHA < 0.1 g/100 ml). The severity of disease was evaluated by scoring daily erythema, infiltration, and desquamation and by a subjective scoring of clinical manifestations offered by the patients. Leukotriene (LT) and platelet-activating factor (PAF) generation were investigated in ionophore-stimulated neutrophils obtained on days 0, 1, 3, 5, 10, and 40. Moderate improvement in clinical manifestations was noted in the n-6 group (changes in score systems between 16-25% from baseline within 10 days). In contrast, the severity of disease markedly decreased in all patients of the n-3 group, with improvements in all score systems ranging between 45% and 76% within 10 days (P < 0.05 for each variable). The difference in response to the two regimens was evident within 4-7 days after onset of lipid infusion. A more than ten fold increase in neutrophil EPA-derived 5-lipoxygenase product formation (LTB5, its omega-oxidation products, non-enzymatic degradation products of LTA5 and 5-hydroxyeicosapentaenoic acid) was noted in the n-3 group but not in the n-6 group. Neutrophil PAF generation increased in the n-6 group but decreased in the n-3 group. In conclusion, modulation of eicosanoid metabolism by intravenous n-3 fatty acid supplementation appears to exert a rapid beneficial effect on inflammatory skin lesions in acute guttate psoriasis.
There is currently no firm evidence on which to base treatment of acute guttate psoriasis. Studies comparing standard treatment modalities, including phototherapy and topical regimens, are required to enable informed decisions on treatment choices to be made.