Allergic contact dermatitis and nail damage mimicking psoriasis caused by nail hardeners

Nail dystrophy mimicking psoriatic disease caused by contact allergy to nail varnish allergens including copolymers

“…Nail dystrophy is a less common presentation and so there may be a delay in patch testing. This case adds to existing reports of formaldehyde in a nail hardener 2 and methacrylate in acrylic nail, 3,4 that induced nail dystrophy, mimicking psoriasis and dystrophy due to cyanoacrylate 5 use. In an attempt to hide dystrophic nails, patients may continue to apply nail cosmetics and inadvertently exacerbate and prolong the problem 6 .…”

Allergic contact dermatitis from formaldehyde mimicking impetigo and initiating rosacea

“…Formaldehyde is a well‐known contact sensitizer, and should be tested at 2.0% aq., as done in the Swedish baseline series since 2014, but the 2 patients were tested before this. All finished products containing formaldehyde or formaldehyde releasers must be labelled with the warning ‘contains formaldehyde’ when the concentration exceeds 0.05% . However, as we can see from these 2 cases, contact allergy to formaldehyde is difficult and sometimes impossible to suspect from the patient's history.…”

Contact Allergy: A Review of Current Problems from a Clinical Perspective

“…Apparent nail psoriasis in 2 Belgian patients was, in fact, due to contact allergy to formaldehyde contained in a nail hardener [ 230 ]. A 26-year-old woman presented with a quickly generalising erythema multiforme (EEM)-like rash spreading from her ankle, where she had applied propolis essence.…”