Atypical Pityriasis Rubra Pilaris Associated with Arthropathy and Osteoporosis: A Case Report with 15‐Year Follow‐Up

Abstract

Pityriasis rubra pilaris (PRP) is an idiopathic papulosquamous disease that clinically presents with palmoplantar keratoderma and follicular hyperkeratotic papules that coalesce into scaly erythematous plaques. We report a unique case of atypical PRP beginning at 1 year of age with associated severe arthropathy and osteoporosis. We further discuss the clinical and histopathologic aspects of PRP, its possible etiology, and other associated conditions.

Systemic sclerosis in a patient with pityriasis rubra pilaris

“…Spontaneous resolution occurs in 80% of patients Page number not for citation purposes 3 within 1-3 years [1,5]. It is characterized by follicular hyperkeratotic papules that coalesce into large, scaly, erythematous plaques, palmoplantar keratoderma, diffuse scaling of the scalp sometimes progressing into erythroderma [1,[6][7][8]. The affected skin is extremely rough to touch [3].…”

“…The affected skin is extremely rough to touch [3]. The histologic features in PRP, although are non-specific, can include irregular acanthosis, alternating orthokeratosis and parakeratosis, hypergranulosis and sparse to moderate lymphocytic perivascular infiltrate of the dermis [7].…”

“…Both familial and acquired forms of the disease have been described [7,910]. PRP has been reported in association with HIV infection [11][12][13], malignancy [4] and Down's syndrome [14].…”

“…PRP has been reported in association with HIV infection [11][12][13], malignancy [4] and Down's syndrome [14]. PRP has been reported to occur simultaneously with several autoimmune disorders [7,6,15,16] including thyroiditis [15,16], myositis [17], myasthenia gravis [18], coeliac sprue [19] and vitiligo [14].…”

“…Recent reports have suggested that immune dysregulation may also play a role in the pathogenesis of PR [7], based on T-lymphocyte abnormalities [27], lymphocyte hypersensitivity to super antigens [28] and relationship to HIV infection [11][12][13]29]. It was speculated that the disorder might be the result of an abnormal immune response to some antigenic stimuli [6,8].…”