Epidemiology of eczematous cheilitis at a tertiary dermatological referral centre in Singapore.

In a retrospective epidemiologic study of 202 patients with eczematous cheilitis attending a patch test clinic, females (182 (90%)) predominated over males (20 (10%)). The mean age of our patients was 30.9 years. There was no significant difference between the mean age of females (31 years) presenting with cheilitis compared to males (29 years). Endogenous cheilitis (53%) was the commonest diagnosis, followed by allergic contact dermatitis (34%) and irritant contact dermatitis (5.4%). A personal history of atopy was recorded in 33%. There was no significant difference in the prevalence of atopy between the sexes or among the diagnoses. The mean duration of cheilitis was 16.4 months. The duration was significantly longer in males (29 months) than in females (15 months) (p=0.004). The mean number of positive patch test reaction in patients with allergic contact cheilitis (2.8) was significantly higher than in those with irritant contact cheilitis (0.2) (p = 0.012) or endogenous cheilitis (0.5) (p = 0.00). The commonest cause of allergic contact cheilitis were lip cosmetics, including lipsticks and lipbalms, followed by toothpastes. The commonest cause of irritant contact cheilitis was lip-licking, lipsticks and medication. In 81/202 (40%) patients, 1 or more causes of contact cheilitis could be ascertained. In females, lip cosmetics were the commonest cause, accounting for 54% (44/81) of cases. Toothpastes accounted for 21% (17/81), followed by topical medication 7% (6/81). For males, toothpastes were the commonest cause of allergic contact cheilitis. Ricinoleic acid and the patient's own lip preparations were the commonest relevant contact allergens.