[Solitary mast cell tumor. A case comunication]. / Mastocitoma solitario. Comunicación de un caso.

BACKGROUND: The solitary cutaneous mastocytoma is a variant of cutaneous mastocytosis which carries a good prognosis. It may develop at a very early age, during the first weeks of life, or even be congenital. Typically, they present as red-brownish lesions that may be asymptomatic or present systemic manifestations associated with histamine release. CASE REPORT: A 19-year-old female patient who attended a medical consultation for a pigmented lesion, slightly raised in the left antecubital fold, asymptomatic, of recent appearance and progressive growth. Dermoscopy reported a fine symmetrical network, yellowish-brown in color and randomly distributed black dots. The pathology report and immunohistochemical findings were consistent with mast cell tumor. CONCLUSIONS: The solitary cutaneous mastocytoma should not be considered as an exclusive entity in the pediatric population. Acknowledgment of its atypical clinical presentation with its dermatoscopic features, is useful for diagnosis.

ANTECEDENTES: El mastocitoma solitario es una variante de mastocitosis cutánea de buen pronóstico, congénita, que aparece durante las primeras semanas de vida. Las manifestaciones clínicas incluyen: lesiones de color rojo-marrón, que pueden ser asintomáticas o generar lesiones sistémicas asociadas con la liberación de histamina. REPORTE DE CASO: Paciente femenina de 19 años, que acudió a consulta médica por una lesión pigmentada, ligeramente sobreelevada en el pliegue antecubital izquierdo, asintomática, de reciente aparición y crecimiento progresivo. La dermatoscopia reportó una fina red simétrica, de color pardo-amarillenta, con puntos negros y distribución al azar. El informe de Anatomía patológica y los hallazgos de inmunohistoquímica fueron compatibles con mastocitoma. CONCLUSIONES: El mastocitoma solitario no es exclusivo de la población pediátrica y su manifestación en la población adulta suele ser atípica. El conocimiento de las características dermatoscópicas es útil para establecer el diagnóstico certero.

Histopathological and clinical evaluation of chronic spontaneous urticaria patients with neutrophilic and non-neutrophilic cutaneous infiltrate.

BACKGROUND: Chronic urticaria has an expressive prevalence in general population, especially in adults, and is defined by the presence of intermittent hives for six weeks or longer. Our study aims to characterize the histological patterns of chronic spontaneous urticaria, based on the inflammatory cell infiltrate, and correlate them to laboratory exams. METHODS: It was performed a retrospective analysis of laboratory, histopathology and direct immunofluorescence data of 93 patients with chronic urticaria. For histopathological analysis, cell count was performed in four fields at high magnification (×400) for each specimen. The resulting cell count medians were submitted to statistical analysis and, then, were correlated to laboratorial findings. RESULTS: We found a female predominance (76.34%) of chronic urticaria cases, and an average age of 42.5 years (SD ± 15). Two histological groups were distinctive: 1) chronic urticaria with predominance of neutrophils or eosinophils - N (%) = 39 (42.4%) - and 2) chronic urticaria with predominance of lymphocytes - N (%) = 53 (57.6%). There was not significant correlation between histological groups and laboratorial tests. Moreover, direct immunofluorescence was positive in 21 (33,87%) from 62 patients. CONCLUSIONS: There is not enough scientific evidence to support neutrophilic urticaria as a solid, separate entity.