Alopecia Universalis: an extremely rare but probable adverse effect of adalimumab

Objective: To report alopecia universalis (AU) as an adverse effect of adalimumab that has not yet been documented in literature. Case Summary: A 50-year-old male was diagnosed with psoriasis and psoriatic arthritis and was commenced on adalimumab subcutaneous injections biweekly. The psoriatic skin lesions and arthritis showed improvement. However, one year later he lost all his body hair including pubic hair. Trichoscopy confirmed AU. Adalimumab was believed to have caused this adverse drug reaction (ADR). He was switched to etanercept with a good response (psoriasis and psoriatic arthritis). However he had no evidence of hair regrowth six months after change of therapy. Discussion: The exact pathogenesis of adalimumab causing hair loss is poorly understood. The patient’s history of psoriasis and psoriatic arthritis conferred an autoimmune diathesis. Adalimumab with its immunomodulatory properties might have been the potential trigger for the development of AU with a sustained or even a permanent injury to the hair follicle as evidenced by absence of hair regrowth at 6-month follow up. Our patient scored a 7 on the Naranjo scale, which signifies that an ADR is the probable cause of AU. Conclusion: This case highlights that AU is a probable ADR of adalimumab. Further studies are needed to assess the duration and reversibility of hair loss. Patients should be promptly educated regarding its occurrence prior to commencement of therapy in order to minimize any associated psychological impact.