Effects of systemic corticosteroids on cutaneous histamine secretion and histamine-releasing factor in patients with chronic idiopathic urticaria.

BACKGROUND

Enhanced skin mast cell releasability of histamine, increased production of histamine releasing factor (HRF), and cutaneous inflammatory process are the hallmarks of chronic idiopathic urticaria (CU). Although H1-antihistamines are known to alleviate the symptoms effectively in most cases, systemic corticosteroids (CS) are given in more resistant patients. Their mode of action remains a matter of controversy.

OBJECTIVES

In the present study, the effects of a 7-day course of CS or placebo on histamine content and HRF production in non-lesional skin of 19 CU patients were examined.

METHODS

Using the skin chamber technique, HRF production and histamine content were assessed in normal-appearing skin of patients with CU over a 2-h observation period. Those two parameters were measured before and after treatment, in a double-blind fashion.

RESULTS

No significant changes occurred in any parameters after placebo treatment. In contrast with this, significant decrease of HRF activity was observed after 1 week of oral methylprednisolone while no change was documented for histamine secretion.

CONCLUSION

These data suggest that CS therapy improves symptoms of CU in association with a decreased production of HRF in uninvolved skin.