[Lymphomatoid papulosis in children: report of 9 cases and review of the literature]. / Papulosis linfomatoide en la infancia: presentación de 9 casos y revisión de la literatura.

BACKGROUND: Lymphomatoid papulosis is a rare lymphoproliferative T cell CD30+ disease with excellent prognosis which affects almost exclusively adult patients, being rarely in the childhood; thus the clinic and pathologic spectrum and the risk of evolution to another type of lymphoma are not well defined in the pediatric group. OBJECTIVE: The aim of this article is to analyze the characteristics of infantile lymphomatoid papulosis and review the literature. MATERIAL AND METHOD: A retrospective study analyzing the characteristics of 9 patients aged up to 18 diagnosed of lymphomatoid papulosis attended in our department from 1995 to 2009 was performed. RESULTS: The study included 7 boys and 2 girls aged between 2 and 17. Pityriasis lichenoides acuta's lesions appeared associated before and after lymphomatoid papulosis' development in 2 and 1 cases respectively. The lesions resolved spontaneously, leaving a postinflammatory hyperpigmentation (77%) or hypopigmentation (23%). The development of varioliform scars occurred in over 77% of cases. Histologically, all cases showed features compatible with type A of lymphomatoid papulosis. Molecular studies showed monoclonality in the 3 cases in which this technique was done. CONCLUSIONS: Infantile lymphomatoid papulosis is a rare entity clinically manifested as the adult form. This lymphoproliferative disease, which is occasionally associated with pityriasis lichenoides acuta, shows features compatible with the type A or histiocytoid pattern in the histological analysis. The development of other lymphoproliferative disorders is less frequent in the infantile form than in the adulthood. The prevalent association among pityriasis lichenoides and lymphomatoid papulosis observed in our analysis, as well as the difficulties which supposed to differentiate between these two pathologies in various cases, suggest that those entities could be part of a common clinical and pathological spectrum.

Papulosis linfomatoide en la infancia: presentación de 9 casos y revisión de la literatura / Lymphomatoid Papulosis in Children: Report of 9 Cases and Review of the Literature

Introducción: La papulosis linfomatoide es un proceso linfoproliferativo de células T CD30+ poco frecuente y de pronóstico excelente que generalmente afecta a adultos y, en menor medida a niños, por lo que tanto el espectro clínicopatológico como el riesgo de progresión a otro tipo de linfoma en el grupo pediátrico no está bien establecido. Objetivo: Analizar las características de la papulosis linfomatoide infantil a partir de la descripción de nuevos casos y de la revisión de la literatura. Material y método: Se realizó un estudio retrospectivo de 9 pacientes menores de 18 años diagnosticados de papulosislinfomatoide atendidos en nuestro servicio entre 1995 y 2009. Resultados: Se incluyeron 7 niños y 2 niñas de edades entre 2 y 17 años. Las lesiones de papulosis linfomatoide se vieron precedidas en 2 casos y seguidas en 1 de otras compatibles con pitiriasis liquenoide aguda. La resolución de las lesiones fue espontánea, dejando hiperpigmentación (77%) o hipopigmentación postinflamatoria (23%) y cicatrices en el 77% de los casos. Histológicamente todos los casos presentaron el patrón tipo A de papulosis linfomatoide. El estudio molecular mostró monoclonalidad en los 3 casos en los que fue realizado. Conclusiones: La papulosis linfomatoide infantil es una entidad rara que se manifiesta clínicamente como la forma adulta. Esta enfermedad linfoproliferativa, que ocasionalmente se asocia a pitiriasis liquenoide aguda, muestra hallazgos histológicos compatibles con el patrón histiocitoide o tipo A. El desarrollo de otros procesos linfoproliferativos malignos en el seguimiento posterior es menos frecuente en la papulosis linfomatoide infantil comparado con la variante adulta. La frecuente asociación de pitiriasis liquenoide y de papulosis linfomatoide encontrada en nuestro análisis, así como la dificultad que supone en algunos casos el diferenciar entre ambos procesos, permite sugerir que ambas patologías podrían formar parte de un espectro clínico-patológico común (AU)

Background: Lymphomatoid papulosis is a rare lymphoproliferative T cell CD30+ disease with excellent prognosis which affects almost exclusively adult patients, being rarely in the childhood; thus the clinic and pathologic spectrum and the risk of evolution to another type of lymphoma are not well defined in the pediatric group. Objective: The aim of this article is to analyze the characteristics of infantile lymphomatoid papulosis and review the literature. Material and method: A retrospective study analyzing the characteristics of 9 patients aged up to 18 diagnosed of lymphomatoid papulosis attended in our department from 1995 to 2009 was performed. Results: The study included 7 boys and 2 girls aged between 2 and 17. Pityriasis lichenoides acuta's lesions appeared associated before and after lymphomatoid papulosisŒ development in 2 and 1 cases respectively.The lesions resolved spontaneously, leaving a postinflammatory hyperpigmentation (77%) or hypopigmentation (23%). The development of varioliform scars occurred in over 77% of cases. Histologically, all cases showed features compatible with type A of lymphomatoid papulosis. Molecular studies showed monoclonality in the 3 cases in which this technique was done. Conclusions: Infantile lymphomatoid papulosis is a rare entity clinically manifested as the adult form. This lymphoproliferative disease, which is occasionally associated with pityriasis lichenoides acuta, shows features compatible with the type A or histiocytoid pattern in the histological analysis. The development of other lymphoproliferative disorders is less frequent in the infantile form than in the adulthood. The prevalent association among pityriasis lichenoides and lymphomatoid papulosis observed in our analysis, as well as the difficulties which supposed to differentiate between these two pathologies in various cases, suggest that those entities could be part of a common clinical and pathological spectrum (AU)