A 54-year-old male presented with a long-standing severe photodistributed eczematous eruption on his face, neck, chest, back, and extremities (Figure 1). His past medical history was significant for severe atopic dermatitis (AD), allergic rhinitis, alopecia universalis, hypertension, and dyslipidemia. His medications included levothyroxine, amlodipine, and atorvastatin.
Diagnostic evaluation included phototesting, patch-testing to the North American Contact Dermatitis Group (NACDG) Standard Series (allergEAZE, SmartPractice, Phoenix, AZ), the Chemotechnique Plant Series (Chemotechnique MB Diagnostics AB, Malmo, Sweden), some of his own products and photopatch-testing to the NACDG Photo Series (allergEAZE, SmartPractice, Phoenix, AZ), in duplicate; one set of allergens was irradiated with 5 J/cm2 of ultraviolet A (UVA) at 24 h., Phototesting revealed a minimal erythema dose (MED) to UVA of 5 J/cm2 and a MED to ultraviolet B (UVB) of 0.05 J/cm2. Methods for patch testing, evaluation of reactions, and data recording followed the NACDG protocol., Haptens were applied using FINN chambers (Smartpractice, Phoenix, AZ) for the NACDG standard and photoseries and IQ Chambers (Dormer Labs, Chemotechnique Diagnostics, Toronto, ON, Canada) were used for the plant series with Scanpor tape (Norgesplaster Alpharma AS, Vennesla, Norway). Patch test results were positive to lanolin, carba, bacitracin, chloroxylenol, and chlorocresol. Photopatch-testing revealed an equally positive reaction on both non-irradiated and irradiated sites to oxybenzone and ethylhexyl methoxycinnamate suggesting the patient had allergic contact dermatitis (ACD), not photo ACD.
Further investigations were performed prior to initiation of systemic therapy including blood chemistry, hepatitis screen, chest x-ray, tuberculin (TB) skin test, and QuantiFERON gold. All testing was negative except for positive induration of 10 mm on TB skin testing due to previous bacille Calmette-Guerin (BCG) vaccine.
Initial management included sun avoidance, photo-protective clothing, UV protective car window glass, UVA and UVB sunscreen (e.g. Anthelios XL 60, La Roche-Posay), Heliocare (Cantabria Labs, Madrid, Spain), and beta-carotene 25,000 units daily. Avoidance of agents he was positive to on patch testing did not improve his CAD. He was prescribed triamcinolone acetonide 0.1% (Aristocort, Valeant, Laval, Canada) and tacrolimus 0.1% ointments.
He was started on methotrexate 15 mg orally once weekly, however, due to gastrointestinal symptoms, not only switched to subcutaneous administration but also discontinued due to extreme fatigue. Mycophenolate mofetil 500 mg twice daily was trialled but discontinued due to elevated liver enzymes. In order, azathioprine 25 mg twice daily (patient was thiopurine methyltransferase heterozygous, therefore, a lower dose was required), hydroxychloroquine 200 mg twice daily, and apremilast 30 mg twice daily were trialled but each discontinued due to inefficacy. He was not able to reach the therapeutic dosage for any of the above agents; therefore, his CAD did not improve.
He was then periodically maintained on cyclosporine 100 mg twice daily (maximum dosage due to elevated blood pressure) until dupilumab became available in Canada, February 2018. He was switched to dupilumab and given a loading dose 600 mg and 300 mg every 2 weeks for maintenance. He partially responded but developed conjunctivitis which was managed with fluorometholone eye drops, dexamethasone ointment, and Refresh tears (Allergan, Unionville, Canada) (Figure 2). To manage periodic flares, he received prednisone over 3-6 weeks.
Due to the patient's partial response to dupliumab, his case was discussed in a joint meeting between the NACDG and International Contact Dermatitis Group (ICDRG) on June 18-19, 2018, in Ottawa, Canada. The recommendations included increasing dupilumab to 300 mg weekly. The use of thalidomide, extracorpeal electrophoresis, and low-dose PUVA (psoralen and UVA) were discussed as potential treatments if symptoms are refractory. Fortunately, this was not necessary.