Filaggrin null mutations and association with contact allergy and allergic contact dermatitis: results from a tertiary dermatology clinic.

BACKGROUND: Filaggrin null (FLG) mutations lead to skin barrier disruption with a reduced resistance towards exogenous agents and also influence the course of disease in atopic dermatitis.
OBJECTIVES: To examine the association between FLG mutations and contact allergy, polysensitization, hand eczema at first appearance of disease, occurrence, and course of dermatitis.
METHODS: A venous blood sample from 430 individuals was genotyped for FLG mutations R501X and 2282del4 with polymerase chain reaction followed by typing through hybridization to paramagnetic polystyrene beads and analysis on a BioPlex 200. All individuals had a minimum of one positive patch test reaction.
RESULTS: In all, 3.5% were 2282del4 heterozygote and 5.1% were R501X heterozygote. An odds ratio (OR) of 1.49 [95% confidence interval (CI) 0.74-3.00] was found for nickel allergy, OR 0.84 (95% CI 0.41-1.74) for polysensitization, OR 0.78 (95% CI 0.25-2.43) for dermatitis, OR 0.96 (95% CI 0.48-1.92) for hand eczema at debut, OR 1.25 (95% CI 0.99-1.57) for duration of disease, and OR 0.76 (95% CI 0.59-0.97) for age at onset.
CONCLUSIONS: No association between nickel allergy, polysensitization, hand eczema at first appearance or occurrence of dermatitis, and FLG mutations was found. However, patients with FLG mutations had an earlier age of onset compared with the wild-type genotype and a trend towards longer duration of disease.