Increased urinary leukotriene E4 excretion in patients with atopic dermatitis.

Background: Synthesis of cysteinyl leukotrienes (LTs) is known to play a part in the pathogenesis of inflammatory diseases.

Objectives: To define the involvement of cysteinyl LTs in atopic dermatitis (AD).

Methods: Synthesis of cysteinyl LTs was assessed in patients with AD and healthy volunteers by measuring urinary LTE4, a useful index of systemic cysteinyl LT synthesis, using liquid chromatography/tandem mass spectrometry.

Results: Mean +/- SD urinary LTE4 levels in patients with AD (125 +/- 69 pg mg(-1) creatinine, n = 20) were significantly higher (P < 0.01) than in healthy volunteers (60 +/- 19 pg mg(-1) creatinine, n = 17). A significant correlation between urinary LTE4 and total serum IgE levels in patients with AD was observed (r = 0.643, P < 0.05).

Conclusions: Our findings demonstrate an enhanced synthesis of cysteinyl LTs in patients with AD and suggest that cysteinyl LTs are involved in the pathophysiology of AD.