Interferon-gamma, immunoglobulin-e and vascular endothelial growth factor in children with papular urticaria

الملخص EN

Background: Papular urticaria (PU) is a common childhood disorder.

It is a chronic allergic disease caused by insect bites.

Both immediate and delayed type hypersensitivity reactions could be involved in the pathogenesis of PU.

The immediate reaction is responsible for the immunoglobulin-E (IgE) response supported by T-helper 2 (Th2) cells while the delayed reaction is mediated by Thl cytokines particularly interferon-gamma (IFN-y).

Mast cells which are effector cells of IgE-mediated immune responses, can release vascular endothelial growth factor (VEGF) after IgE-dependant activation.

VEGF was reported to play a role in the pathogenesis of many allergic conditions.

Patients and Methods: This study included 28 children with papular urticaria and 15 age and sex-matched healthy controls.

The age of the patients ranged from 2 to 7 years (mean, 3.5 years).

The duration of PU ranged from 3 months to 4 years.

IFN-y, IgE and VEGF levels were quantitatively determined in serum of patients and controls by Enzyme Linked Immuno-Sorbent Assays (.ELISA).

Results: Children with papular urticaria showed significantly elevated serum levels of IFN-y, IgE and VEGF compared to healthy controls (p<0.05, p<0.001 andp<0.001 respectively ).

A significant positive correlation was demonstrated between serum levels of IFN-y and IgE in children with papular urticaria (r = 0.941, p<0.01). Conclusions: Papular urticaria could be mediated by a complex immune response involving more than one mechanism, with evidence for both Thl response (increased production of IFN-y) and Th2 response (increased production of IgE) with a possible role for VEGF.