Acrodermatitis Continua of Hallopeau as a Manifestation of Pustular Psoriasis. Case Report.

Introduction Acrodermatitis continua of Hallopeau (ACH) is a rare localized pustular psoriasis that primarily affects the distal phalanges and nails [1]. ACH is often misdiagnosed and may progress to onychodystrophy, anonychia, osteitis, or, in some cases, evolve into generalized pustular psoriasis [2,3]. We present a case of this visually distinctive and infrequently reported dermatosis, along with successful treatment approach. Case Presentation A 33-year-old male, previously treated with three courses of itraconazole pulse-therapy for thickened, brittle toenails associated with paronychia, pustules, erosions on the soles of the feet, was hospitalized due to newly onset knee pain, swelling of the ankle joints, and arisen moist papules covered with fine scales in the navel area. Joint involvement, can be associated with ACH, as it is a localized form of pustular psoriasis strongly linked to psoriatic arthritis [6]. The differential diagnosis included nail fungus with secondary infection, contact dermatitis with secondary pyoderma and Reiter’s disease. These were excluded through a combination of negative KOH microscopy, lack of fungal growth, normal radiographic findings and the absence of other clinical features or signs of infection. Furthermore, histologic findings were characteristic of ACH. The patient responded well to a combination of systemic therapies, including acitretin (tapered from 60 mg/day to a maintenance dose of 20 mg/day over 14 weeks), and prednisolone (20 mg/day for 30 days), along with topical treatments (clobetasol and calcipotriol). Discussion ACH has been recognized as an extraordinary clinical entity reported infrequently around the globe. While other dermatoses can resemble ACH, the pustular form of psoriasis accompanied by nail involvement and early onset of joint pain, strongly points toward this diagnosis [1, 4]. Due to rarity, there aren't defined criteria for treating ACH, instead, case reports with a variety of therapeutic techniques and outcomes are available [5]. Conclusions Dermatologists must vigilantly seek for accurate and early diagnosis. Acrodermatitis continua of Hallopeau is diagnosed via recognition of consistent clinical and histologic findings. A long-term combination of systemic and topical medicine is the most preferred option, highlighting the value of multidisciplinary approach to managing ACH.