BH05 Successful treatment of acrodermatitis continua of Hallopeau with methotrexate

Abstract

Abstract A 39-year-old woman was referred with a 3-month history of brittle nails, painful fingertips and psoriasiform plaques affecting her torso and limbs. She had a past medical history of macrocytic anaemia secondary to dietary B12 and folate deficiencies, which required inpatient transfusions. She had no previous dermatological concerns, and there was no history of infection or trauma to the affected sites. On examination of her hands and feet, there was evidence of nailbed pustulation, subungual hyperkeratosis, onychodystrophy, anonychia of multiple nails and dactylitis, consistent with acrodermatitis continua of Hallopeau (ACH) with associated psoriasis. At diagnosis, the patient’s Dermatology Life Quality Index (DLQI) was 16, she had a Psoriasis Area and Severity Index (PASI) score of 18 and a Psoriasis Epidemiology Screening Tool (PEST) score of 4. Nail fungal culture was negative. Plain radiographs of the hands and feet demonstrated a flexion deformity of the left fifth finger distal interphalangeal joint, with otherwise normal bone texture, alignment and joint spaces. The patient was initially treated with potent topical corticosteroids and vitamin D analogues, with little improvement. The patient was commenced on 15 mg subcutaneous methotrexate (MTX), with close monitoring of serum and red cell folate given her background of folate deficiency, which was being actively replaced. Within 3 months of starting MTX monotherapy, the patient’s hands had dramatically improved with skin and fingernail changes largely resolved, and an improvement in manual dexterity (DLQI 11, PASI 3, PEST 5). MTX was increased to 20 mg once weekly and the patient was also started on sulfasalazine 500 mg twice daily by her rheumatologist for psoriatic arthritis. ACH is a chronic pustular eruption initially affecting distal phalanges with gradual proximal progression and the potential development of generalized pustular psoriasis. ACH is considered a variant of palmoplantar pustulosis, commonly affecting adult females with localized trauma and infection as possible triggers. Given the rarity of ACH, the evidence base for therapy is limited to case reports and series, with no standardized treatment guidelines. Topical therapies include corticosteroids, calcineurin inhibitors and vitamin D analogues. Local phototherapy and systemic therapy with acitretin, MTX and ciclosporin have been described, with wide-ranging results. In severe cases such as this, patients typically receive biologic therapy, with variable responses reported with tumour necrosis factor-α inhibitors, anti-interleukin (IL)-6 therapy, and anti-IL-12/IL-23 and anti-IL-17 therapy. We present a rare case of severe ACH and psoriasis, treated with MTX monotherapy, which was not only clinically effective but also cost-effective.