ABSTRACT
Alopecia areata (AA) is a common form of nonscarring hair loss. It is believed to be a consequence of an immune-mediated stimulus, probably involving autoreactive T cells against antigens present in the hair follicle. The exact antigen is still unknown; however, some authors have proposed that melanogenesis-associated molecules might trigger autoimmunity. Although transient white hair regrowth is a common and well-known situation in AA, there are other types of white hair phenomena in this context, including permanent white hair regrowth, sparing of white hair in a patchy pattern, or sparing in a diffuse pattern, giving the appearance of the so-called overnight graying phenomena or canitis subita. In this review, we aim to describe the different clinical aspects of white hair in AA, as well as the proposed pathophysiologic mechanisms involved in this phenomena.
Subject(s)
Alopecia Areata , Hair Diseases , Humans , Hair Follicle/pathology , Hair Diseases/pathology , Hair ColorABSTRACT
Cutaneous malakoplakia is a rare infection-related granulomatous disease frequently associated with immunocompromised states. Foamy macrophages containing basophilic granules, called the Michaelis-Gutman bodies, are pathognomonic. We report a case of cutaneous malakoplakia in a 77-year-old male with pyoderma gangrenosum and a 2-year history of a non-healing malleolar ulcer treated successfully with cotrimoxazole.
Subject(s)
Immunocompromised Host , Malacoplakia/drug therapy , Malacoplakia/etiology , Pyoderma Gangrenosum/complications , Pyoderma Gangrenosum/drug therapy , Administration, Cutaneous , Aged , Humans , Male , Treatment OutcomeABSTRACT
Introducción. Las neoplasias linfoides de los anexos oculares ocupan del 7 al 8% de todos los linfomas extranodales. De éstos, el más frecuente es el linfoma B de la zona marginal extranodal de tejido linfoide asociado a mucosas (MALT), seguido del linfoma B difuso de células grandes. Algunos agentes infecciosos se han asociado de forma inconstante en la etiología de los linfomas MALT. También se han encontrado translocaciones características, que en su mayoría causan la activación del factor nuclear unido al promotor de cadenas ligeras kappa de los linfocitos B activados (NF-κB). Los linfomas MALT son el tipo de linfoma predominante en la conjuntiva y en los anexos oculares. El promedio de edad es de 61 años, siendo muy raros antes de los 25 años y predominando en el sexo femenino. Material y método. Se revisó el archivo de la Unidad de Patología Quirúrgica del Hospital General de México (2003-2010). Resultados. Se encontraron 12 casos de tipo MALT. El espectro de edad fluctuó entre los 23 y los 74 años, con promedio de 50,7 años; 7 (58,3%) fueron del sexo femenino y 5 (41,6%) pacientes del sexo masculino. Presentaron morfología de linfoma de linfocitos pequeños tipo MALT y se realizó inmunohistoquímica para confirmar el diagnóstico(AU)
Introduction. Lymphoid ocular adnexa neoplasms comprise 7-8% of all extranodal lymphomas, the most common being the extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma), followed by diffuse large B-cell lymphoma. Some infectious organisms may play an aetiological role in the development of MALT lymphomas, although this is not a consistent finding. Specific translocations have also been identified which cause activation of nuclear factor bound to the promoter kappa light chains of activated B-lymphocites (NF-kB). MALT lymphomas are the predominant type of lymphoma in the conjunctiva and other occular adnexa. They occur more frequently in females and the average age of patients is 61; they are extremely rare before the age of 25. Material and methods. Clinical and morphological data from biopsies diagnosed as MALT lymphoma, from the General Hospital of Mexico during the years 2003 to 2010, were reviewed. Results. Of the 12 cases found, the age range was 23 to 74, with an average age of 50.7; 7 (58.3%) were female and 5 (41.6%) were male. The morphology of the present cases was that of small lymphocytic lymphoma (MALT lymphoma) and the diagnosis was confirmed by immunohistochemistry(AU)
