Enfermedades poco frecuentes. Halo nevus. Presentación de un caso clínico / Rare diseases. Halo nevus. Presentation of a clinical case

El Halo Nevus consiste en un área hipopigmentada que rodea un nevus melanocítico preexistente y lo hace desaparecer, dejando una cicatriz hipocrómica en el lugar del nevo. Un 20% puede malignizarse. Se presenta un adolescente con lesiones en sus diferentes estados evolutivos, sin sintomatología adicional, ni antecedentes familiares. Es importante el seguimiento clínico y dermatológico para detectar signos tempranos de malignización con el consiguiente tratamiento oportuno

Summary Halo Nevus consists is an hypopigmented area surrounding a pre-existing melanocytic nevus and make it desappared leaving a hypochromic scar in it place, and 20% may become malignant. We present an adolescent with lesions in their different stages of evolution, without additional symptoms or family history. Clinical and dermatological follow-up is important to detect early signs of malignancy with the following timely treatment

Criterios dermatoscópicos de halo nevo y halo melanoma / Dermoscopy criteria of halo nevi and halo melanoma

El fenómeno halo es más común en lesiones melanocíticas benignas. Se han reportado casos de halo nevo en individuos con antecedentes personales o familiares de melanoma como también melanomas con halo lo que ha suscitado preocupaciones acerca del diagnóstico y manejo de estas lesiones. El halo nevo pertenece al grupo de los simuladores de melanoma. A través de una técnica no invasiva como es la dermatoscopia se puede diferenciar las características dermatoscópicas del halo nevo y halo melanoma

Halo phenomenon appears more often in benign melanocytic lesions. There have been reports of halo nevi in individuals with personal or family history of melanoma as well as melanomas with halo, raising concerns about the diagnosis and management of these lesions. Halo nevus belongs to the group of melanoma simulators. Dermoscopic features of halo nevus and melanoma can be differentiated through a noninvasive technique such as dermoscopy.

Poliosis of Eyelashes as an Unusual Sign of a Halo Nevus

A 39-year-old man with poliosis of his lower eyelid lashes visited our clinic. He reported that his symptoms began with a few central lashes and then spread along the adjacent lashes during the ensuing 2 weeks. A pigmented nevus, approximately 4 mm in diameter, was identified just above the white lashes without surrounding skin depigmentation. No specific findings were identified with regard to the patient's general health or serologic and radiologic testing. Excisional biopsy of the pigmented nevus was performed. On histopathologic examination, infiltration of the dermis by numerous lymphocytes and melanophages was observed. The poliosis was ultimately diagnosed as a presenting sign of the halo phenomenon in the regressive stage of a melanocytic nevus.