Hereditary ichthyoses are a group of genetic disorders of cornification, which are characterised by hyperkeratosis and scaling. The new classification identifies 36 types of ichthyosis, which are subdivided according to their frequency, pattern of inheritance and extracutaneous involvement. The diagnosis is mainly based on clinical features, since genetic studies are not available in our setting. Treatment is symptomatic and management should be performed by a multidisciplinary team. In this article, the diagnostic and therapeutic aspects of different types of ichthyosis are reviewed, taking into account the nomenclature and modifications presented in the new classification.

Las ictiosis hereditarias son un grupo de trastornos genéticos de la cornificación, que se caracterizan por presentar hiperqueratosis y/o descamación. La nueva clasificación identifica 36 tipos de ictiosis, las cuales se subdividen según su frecuencia, patrón de herencia y compromiso extracutáneo. El diagnóstico se basa principalmente en las características clínicas, ya que los estudios genéticos no se encuentran disponibles en nuestro medio. El tratamiento es sintomático y su manejo debe ser realizado por un equipo multidisciplinario. En este artículo se revisan los aspectos diagnósticos y terapéuticos de los distintos tipos de ictiosis, considerando la nomenclatura y modificaciones expuestas en la nueva clasificación.

Nail alterations in children are a very frequent cause for consultation in primary care, pediatrics and dermatology. Its exact prevalence is unknown. Some of them are identical to those in adults, but there are some whose frequency is much higher in children, because they arise or develop exclusively in that period of life. Although some ungueal changes are considered isolated anomalies that have only cosmetic relevance, others might be diagnostic clues of associated diseases; they may be disabling and have a prognostic value for adult life. For that reason, good knowledge and proper management of them by specialists is fundamental. This report describes main alterations that may be observed in the ungueal apparatus during childhood, due to physiological alterations and congenital or acquired disease.

Las alteraciones ungueales en los niños representan un motivo de consulta frecuente en atención primaria, pediatría y dermatología. Su prevalencia exacta se desconoce. Algunas alteraciones son idénticas a las de los adultos, pero existen otras que se observan con mayor frecuencia en niños ya que se presentan o desarrollan exclusivamente en esta etapa de la vida. Aunque algunos cambios ungueales sean considerados como anomalías aisladas de importancia sólo cosmética, otros pueden ser claves diagnósticas para enfermedades asociadas, pueden ser discapacitantes y pueden tener importancia pronostica en la vida adulta. Por esto un adecuado reconocimiento y manejo por parte del especialista es fundamental. En este artículo se describen las principales alteraciones fisiológicas y enfermedades congénitas o adquiridas que se pueden observar en el aparato ungueal durante la infancia.

During the recent 10 years the ozone layer has decreased while ultraviolet radiation has increased in Santiago, Chile. Aim: To determine whether the number of sunburns in children correlate with ultraviolet radiation in Santiago. Subjects and methods: During six Austral Summers (1996-2001) children below 15 years old, consulting for sunburn, were evaluated at the "Corporation for the Aid of Burned Children" (COANIQUEM) in Santiago (33.5°S). The number of children with sunburns during each Summer was compared with the corresponding UV-B radiation and the ozone thickness, to establish a probable relation between a geophysical change and its consequences in skin health. The ozone layer values were obtained from the NASA WEB-page and the ultraviolet radiation was measured with a four-channel medium resolution radiometer. Results: In each Summer there was a predominance of sunburns among boys and among ages between 6 and 10 years. During the 96-97 Austral Summer, the highest number of children with sunburns (63) was diagnosed. That Summer also had the highest mean UV-305 nm radiation with an important amount of days with ozone 260 Dobson Units. Only during that Summer an inverse correlation between ozone and UV-305 nm radiation was detected. At the same time the maximal values of Erythemal Dose Rate (33 µWatt cm-2), UV Index (13) and Erythemal Daily Dose (7.500 Joule m-2) were observed. Conclusions: In Santiago, Summers with a higher number of days with low ozone protection seem to reappear every 3 years. Understanding the interaction of physical processes that control the ozone layer, may help to design better photo-protection programs for human health

Background: Pyoderma gangrenosum is an ulcerative disease of the skin of unknown cause and generally associated to systemic illnesses. It requires an aggressive systemic therapy and there is little information about its long term evolution. Aim: To report the clinical features of patients with pyoderma gangrenosum. Patients and methods: Eleven patients (10 female) aged 27 to 81 years old with pyoderma gangrenosum are reported. All had a pathological study. Patients were followed up for a mean of 60 months. Results: The lesions were located in the lower limbs in 8 patients. Pathological study showed neutrophyl infiltrates in nine patients. Three patients had an ulcerative colitis and one, a Crohn disease. During the follow up, the disease recurred in multiple occasions, in six patients, after treatment with steroids or sulphones, and one patient has had permanently active lesions. Conclusions: Pyoderma gangrenosum appears mostly in the lower limbs and has a high recurrence rate (Rev Méd Chile 2001; 129: 1044-50)