Pityriasis amiantacea: a study of seven cases

Abstract

Pityriasis amiantacea was first described in 1832. The disease may be secondary to any skin condition that primarily affects the scalp, including seborrheic dermatitis. Its pathogenesis remains uncertain. We aim to analyze the epidemiological and clinical profiles of patients with pityriasis amiantacea to better understand treatment responses. We identified seven cases of pityriasis amiantacea and a female predominance in a sample of 63 pediatric patients with seborrheic dermatitis followed for an average of 20.4 months. We reported a mean age of 5.9 years. Five patients were female, with a mean age of 9 years. All patients were successfully treated with topic ketoconazole.

Development of pityriasis amiantacea after valproic acid therapy

“…Since then, several names including tinea amintacea, asbestos scalp, tinea asbestina, or keratosis follicularis amiantacea have been used to describe PA.[1] PA has been described more commonly in the context of SD (one-third of cases); however, in addition, there are some reports in the setting of psoriasis vulgaris (other third of cases), followed by lichen planus, lichen simplex chronicus, atopic dermatitis, Darier's disease, tinea capitis, and pyogenic infections. [245] Several factors have been implicated in PA development such as drugs, anxiety, and abrupt changes in the environmental conditions. [678] Some descriptive data support a probable participation of tumor necrosis factor-alpha (TNF-α) and interferon-α in the pathogenesis of PA.[67] In patients with Crohn's disease treated with TNF-α inhibitors, a stimulation of alternative pro-inflammatory pathways, including up-regulation of the IL-1 family, potential generation of autoreactive T cells, and keratinocyte proliferation, is observed.…”

“…In severe cases, high-potency topical corticosteroids are beneficial (betamethasone dipropionate 0.1% solution). [2] In extensive and persistent disease, topical and oral retinoids are usually necessary taking precautions because of their teratogenicity. [14]…”

“…Pityriasis amiantacea (PA) is a distinct inflammatory scaling reaction of the scalp that is characterized by the generation of firmly adherent, thick, waxy scales, which surround and attach to the hair bundles and take a silvery or yellowish coloration. [12] The pathogenesis of PA remains almost completely unknown; its low frequency and diverse presentations have made PA a controversial disorder. Currently, evidence appears to indicate that PA is a prominent autoinflammatory response with possible participation of genetic and environmental factors.…”

Pityriasis in dermatology: an updated review

“…PAMI may present in any age group, however is most common in children and adolescents with a female predominance 9–11 …”

Trigeminal trophic syndrome simulating pityriasis amiantacea

“…Among the possible etiologies are seborrheic dermatitis as the most frequent, followed by psoriasis and local infections. [6]…”