Veronica Lepe

Lichen Amyloidosis Improved by 0.1% Topical Tacrolimus

Lichen amyloidosis (LA) is a chronic pruritic disorder characterized by cutaneous amyloid deposition without systemic involvement. Clinical features consist in intensely pruritic hyperkeratotic papules that coalesce into plaques, mostly found on the anterior legs, upper back, forearms and thighs. Treatments available are generally nonsatisfactory, and new therapeutic options are long overdue. They usually rely on topical or intralesional corticosteroids [1–3], although UV therapy [2], dimethyl sulfoxide [4], surgical procedures [5], retinoids [6], calcipotriol [1] and oral immunosuppressants [7] have also been reported to be beneficial. A previously healthy 46-year-old woman presented to our outpatient clinic with an 18-month history of intensely pruritic hyperkeratotic brown papules that coalesced into infiltrated plaques on the ventral side of her left shin and both elbows quite characteristic of LA (fig. 1). She had previously been treated with clobetasol propionate 0.05% ointment and intralesional triamcinolone acetonide along with sedative antihistaminics, producing only a limited and transient response. With the purpose to ameliorate the itch in this patient, we tried tacrolimus 0.1% ointment twice a day on the affected areas given its proven effectiveness in lichenified atopic dermatitis [8]. After a 2-week trial, we observed resolution of the pruritus, but, more strikingly, a marked improvement in thickness of the plaques was obtained after 2 months of continuous application (fig. 2). Scratching is probably the first and single most important feature in the development of lesions of LA [9]. Following this, keratin peptides of apoptotic keratinocytes are transformed by dermal macrophages and fibroblasts into amyloid fibrils [10]. Because deposition of amyloid is not the cause but may be the result of friction, treatment should be aimed at alleviating the pruritus instead of removing

Dosis de radiación ultravioleta en escolares mexicanos

OBJETIVO: Determinar la dosis de radiacion ultravioleta que reciben los ninos y adolescentes durante su asistencia a la escuela primaria, secundaria o preparatoria en la ciudad de San Luis Potosi. MATERIAL Y METODOS: Estudio de cohorte hecho en la ciudad de San Luis Potosi entre mayo de 2001 y abril de 2002. Se evaluaron 80 escolares escogidos al azar de 6 a 19 anos de edad, de uno u otro sexo. La dosis se cuantifico durante todo un ciclo escolar mediante el registro del tiempo de exposicion solar para cada uno de los alumnos, de modo simultaneo al monitoreo de radiacion ultravioleta, para lo cual se utilizaron equipos de radiometria terrestre. Se excluyeron las vacaciones y los fines de semana. Los datos se analizaron en forma univariada y comparativamente, por sexo y meses de exposicion; ademas, se busco un modelo de regresion para explicar la dosis de exposicion solar. RESULTADOS: La dosis promedio ajustada al espectro de eritematogeno accion fue de 16 456 J/m²/ano.Hubo diferencias por genero: 14 264 J/m²/ano/mujeres vs. 18 648 J/m²/ano/hombres (Kolmogorov-Smirnof, p=0.003). No hubo diferencias significativas entre grupos, pero si entre los meses de exposicion (Kruskall-Wallis, p=<0.0001). Utilizando la tecnica estadistica de modelos lineales generalizados, y mediante tecnica escalonada y calificacion del indice de Akaike se escogio el mejor modelo que explica la dosis de radiacion segun el mes de exposicion, mediante la formula 587.20+438.45 (genero)+500.16(mes)-49.65(mes²). El resultado muestra mayores dosis de radiacion de marzo a septiembre. CONCLUSIONES: Proponemos un marco teorico para la creacion de politicas dirigidas a proteger a los alumnos de la sobrexposicion solar durante su asistencia a la escuela en Mexico. Se justifica la implantacion de medidas preventivas durante al menos el periodo de mayor exposicion (marzo a junio), ya que en este lapso se recibe 51% de la dosis anual de radiacion ultravioleta. Si se evitara la exposicion de 8 min/dia se podrian reducir 39 495 J/m², dosis que actualmente se acumula en dos anos.

Subungual Chondroblastoma in a 9-Year-Old Girl

Abstract:  Chondroblastoma is an uncommon primary bone tumor, mainly found in the epiphyses of long bones. We describe a 9‐year‐old girl who presented with a chondroblastoma as a subungual mass in the fifth toe. Radiographs showed an expansive, calcified tumor of the distal phalanx. Histologic examination after excision revealed chondroid differentiation, active mitosis, multinucleated giant cells, calcification, and necrosis. There was no recurrence of the lesion after surgical excision. The purpose of this report is to document this unusual event that occurred in such a short bone as the distal phalanx of the fifth toe, mimicking a dermatologic entity.

Antivirals for pityriasis rosae

To the Editor, We appreciate the comments by Dr Chuh about our brief article (1). Concerning the absence of clinical trials with phototherapy for pityriasis rosea (PR), we were certainly aware of the study of Arndt et al. (2). Nevertheless, their inaccurate methods of evaluation precluded its consideration as a valid clinical trial. Regarding possible spontaneous new lesions and their resolution, we stress the following points: (A) We observed a young patient with a persistent form of PR for the last 3 weeks. (B) His lesions were promptly exacerbated by repeated exposure to UVB-NB in a lapse of 1 week