The incidence of psoriasis in Chile: an analysis of the National Waiting List Repository.

BACKGROUND: Psoriasis is a serious and chronic noncommunicable disease. However, the fundamental measure of disease occurrence, the incidence, has been scarcely reported globally. There are no previous studies of psoriasis incidence in Latin America. AIM: To estimate the incidence rates of psoriasis in Chile during 2016 and 2017 using an administrative database, the Waiting List Repository. METHODS: We examined referrals of psoriasis at onset, made by physicians to dermatologists, evaluated the agreement of diagnosis, and estimated the incidence of the disease considering the eligible population at risk. RESULTS: In most cases, the referrals corresponded to incident cases of psoriasis (73.3%; 95% CI: 66.6-79.2). The national incidence rates of psoriasis were 22.1 (95% CI: 21.1-23.1) and 22.7 (95% CI: 21.8-23.6) per 100 000 person-years in 2016 and 2017, respectively. The most common type of psoriasis was the late-onset type. We observed a high variation in the figures throughout the country, with a range from 0.75 (95% CI: 0.3-1.5) per 100 000 person-years in the Metropolitan region to 164.9 (95% CI: 138.6-195.1) per 100 000 person-years in the Aysen region. CONCLUSION: We describe for the first time the incidence of psoriasis in a Latin American country. Our findings could potentially guide collaborations to improve our global understanding of psoriasis in Latin America.

Psoriasis pustulosa generalizada / Generalized pustular psoriasis

Introducción: la psoriasis pustulosa generalizada (PPG) es una forma grave de psoriasis asociada a manifestaciones sistémicas. Es una enfermedad infrecuente y potencialmente letal. En las últimas décadas, se ha avanzado mucho en la comprensión de su fisiopatología, gracias a estudios inmunológicos y genéticos. Objetivo y método: El objetivo de esta revisión es actualizar los conceptos respecto a la fisiopatología, diagnóstico y tratamiento de la PPG. Se realizó una revisión del tema mediante una búsqueda bibliográfica en Pubmed y LILACS en los últimos 10 años, y además se agregaron referencias relevantes que no se encontraran en los resultados. Resultados: La PPG podría comprenderse como una enfermedad del grupo de las enfermedades autoinflamatorias, cuya causa es una mutación en el gen IL36RN, que produciría una falla estructural o una secreción inadecuada del antagonista del receptor de IL36, lo que conduciría a un desbalance en la contra-regulación de las citoquinas pro-inflamatorias de la familia IL-1. Su gatillante más frecuente es la interrupción abrupta del uso de corticoides, aunque existen numerosos factores reportados. El tratamiento de primera línea es la hospitalización, manejo con terapia tópica y sistémica con retinoides o terapia biológica, para luego continuar con un esquema de mantención. Conclusión: Dado los avances en su investigación, la PPG podría considerarse una entidad etiológicamente distinta a la psoriasis común.

Introduction: generalized pustular psoriasis (GPP) is a severe form of psoriasis associated with systemic manifestations. It is a rare and potentially lethal disease. In recent decades, much progress has been made in understanding its pathophysiology, thanks to immunological and genetic studies. Objective and Methods: The aim of this review is to update the concepts regarding the pathophysiology, diagnosis and treatment of GPP. A review was performed by searching in PubMed and LILACS databases in the last 10 years, also relevant references that were not in the results were aggregated. Results: GPP could be understood as a disease of the group of autoinflammatory diseases, caused by a mutation in the gene IL36RN that produce structural failure or an inadequate secretion of IL36 receptor antagonist, leading to an imbalance in the counter-regulation of the pro-inflammatory cytokines from the IL-1 family. Its most common trigger is the abrupt discontinuation of corticosteroids, although there are numerous factors reported. The first line treatment is hospitalization, management with topical and systemic retinoid therapy or biological therapy, and continue with a scheme of maintenance afterwards. Conclusion: Due to the progress in its investigation, GPP could be regarded as an etiologically distinct entity to psoriasis vulgaris.