Porokeratosis ptychotropica: a rare and evolving variant of porokeratosis.

Porokeratosis ptychotropica represents a rare and under-recognized variant of porokeratosis. There are also alternative descriptions for this disorder in the literature. Since its original description in 1995, additional characteristic features have been showed in case reports published in the literature. These cumulative reports, although still limited in numbers, have helped to further shape and define this entity. A case report and review of published literature on this unusual entity are presented. The specific combination of clinical, morphological and histopathological characteristics that can facilitate recognition of the disorder is discussed. There has been a call for uniformity in terminology and a suggestion for alternative terminology has been made. However, we discuss why the earlier term, porokeratosis ptychotropica, is still preferred.

Sensitization to dimethyl fumarate with multiple concurrent patch test reactions.

BACKGROUND: Chairs and sofas imported from China to Europe were shown to contain dimethyl fumarate (DMF), a sensitizing, volatile chemical. Many of the sensitized patients also had positive patch test reactions to acrylates. OBJECTIVES: To analyse the occurrence and strength of DMF sensitization and the appearance of concomitant reactions. METHODS: Patch testing with DMF in concentrations of 0.1-0.00001% was carried out in 37 patients. Diethyl fumarate (DEF), diethyl maleate (DEM), dimethyl maleate (DMM), ethyl acrylate (EA), methyl acrylate (MA), and methyl methacrylate (MMA) were also tested with a dilution series at equimolar concentrations. RESULTS: The lowest concentration of DMF eliciting a reaction varied between 0.0001% and 0.1% and all but four patients reacted concurrently to DEF. DEM elicited positive patch test reactions in 21/37 patients and DMM reactions were seen in all 9 patients tested. EA elicited positive reactions in 13/37 patients and a positive MA reaction was seen in 7/37 patients, 2 of whom also reacted to MMA. CONCLUSIONS: The strength of the sensitization to DMF showed variation and concurrent reactions were common. Concurrent reactions to (meth)acrylates were seen in patients, who reacted to lower (0.001% or less) DMF concentration probably elicited by cross-reactivity.

Susceptibility to UV-A and UV-B provocation does not correlate with disease severity of polymorphic light eruption.

OBJECTIVE: To examine whether the ease of disease provocation by UV-A and/or UV-B radiation correlates with clinical features of polymorphic light eruption (PLE), including those indicative of disease severity. DESIGN: Intervention study. PATIENTS: One hundred forty-three patients with PLE. INTERVENTIONS: Provocation testing with broadband UV-A and UV-B lamps. Additionally, a range of clinical characteristics of the disorder, including a 5-item PLE severity score, was assessed by questionnaire. MAIN OUTCOME MEASURES: Percentage of PLE rash induction by UV-A and UV-B provocation, differences between the skin types, and correlation between the results of provocation and a range of clinical characteristics of the disorder, including a 5-item PLE severity score. RESULTS: Rash provocation was seen in 78.3% of patients after UV-A and in 46.7% after UV-B exposure. Neither UV-A nor UV-B provocation showed a significant association with the total 5-item severity score. The UV-B reactivity was associated with a high score on the severity item "number of months affected per year" (P = .04), whereas UV-A responsiveness showed a tendency for association with facial involvement (P = .06). CONCLUSION: The objective assessment of UV-A or UV-B susceptibility in this large group of patients showed no significant relationship with clinical disease severity.