Allergic contact dermatitis in patients with frontal fibrosing alopecia: An international multi‐center study

Abstract

Frontal fibrosing alopecia (FFA) mainly affects the anterior hairline and eyebrows and its etiology and associated factors remain obscure. The aim of this study was to evaluate the allergic contact dermatitis with patch test in patients with FFA. In this prospective study, 20 patients with FFA and 24 age and sex‐matched healthy individuals were evaluated with patch testing. Diagnosis was made histologically, clinically and based on dermoscopic findings. Demographic data, age of onset, disease duration and FFA severity index are evaluated in all patients. Positive patch test reaction to one or more allergen was observed in 65% of patients while it was 37.5% in control group (P = .003). There was a significant difference between age (P = .006) and positive patch test results. No statistical significant difference was observed in the results of patch testing and disease duration (P = .519), menopausal status (P = .085), and FFA severity index (P = .573). Our findings suggest an association between FFA and allergic contact dermatitis. The utility of patch testing in FFA patients can explore the role of allergic etiology and may have an enormous impact on the diagnostic potential and quality of life of these patients.

Response to Letter to the Editor

“…This remains an enigma, thus provided the triggers are identified, patients would have an opportunity to actively prevent the origination and/or progression of the disease.Prior research found that, among patients with FFA, cosmetics use (eg, sunscreens) is pronounced 2-4 and patch-test reactions are frequent. 2,[5][6][7] We found frequent sensitization to allergens, such as BS (22%), gallates (16.6%), propolis (16.6%), and limonene hydroperoxides (13.8%) in 36 patients with FFA. 1 Of interest, in some patients, reactions to BS, gallates, and propolis seemed to be concomitant, 1 suggesting a peculiar allergenic profile.…”

Frontal Fibrosing Alopecia: A Review

“…A higher frequency of positive patch test in FFA patients, mainly for fragrances [ 93 ], benzyl salicylate [ 102 ], cobalt, nickel, and potassium dichromate [ 103 ], have been found in different studies, although others do not suggest any association of FFA with photoallergy to several cosmetic-related substances (including chemical sunscreen filters) or titanium dioxide [ 100 , 104 ]. Moreover, the positive patch test may be a consequence of increased exposure to these substances.…”

Association of frontal fibrosing alopecia and contact allergens in everyday skincare products in Hispanic females: a case-control study

“…The most common allergens encountered in the FFA group were cobalt chloride hexahydrate 35%, nickel sulfate hexahydrate 25%, and potassium dichromate 15%. 7 In our study, 83.3% of cases and 55.5% of controls had at least one positive allergen.…”