RESUMEN
BACKGROUND: Alopecia areata (AA) is a common disorder of unknown etiology that affects approximately 0.7% to 3.8% of patients among the general population. Currently, genetic and autoimmune factors are emphasized as etiopathogenic. Studies linking Human Leukocyte Antigens (HLA) to AA have suggested that immunogenetic factors may play a role in the disease's onset/development. OBJECTIVES: To investigate an association between AA and HLA class I/II in white Brazilians. METHODS: Patients and control groups comprised 33 and 112 individuals, respectively. DNA extraction was performed by column method with BioPur kit. Allele's classification was undertaken using the PCR-SSO technique. HLA frequencies were obtained through direct counting and subjected to comparison by means of the chi-square test. RESULTS: Most patients were aged over 16, with no familial history, and developed partial AA, with no recurrent episodes. Patients showed a higher frequency of HLA-B*40, HLA-B*45, HLA-B*53 and HLA-C*04 compared with controls, although P was not significant after Bonferroni correction. Regarding HLA class II, only HLA-DRB1*07 revealed statistical significance; nevertheless, it featured more prominently in controls than patients (P=0.04; Pc=0.52; OR=0.29; 95%; CI=0.07 to 1.25). P was not significant after Bonferroni correction. CONCLUSIONS: The development of AA does not seem to be associated with HLA in white Brazilians, nor with susceptibility or resistance. The studies were carried out in populations with little or no miscegenation, unlike the Brazilian population in general, which could explain the inconsistency found.
Asunto(s)
Antígenos de Histocompatibilidad Clase II/genética , Antígenos de Histocompatibilidad Clase I/genética , Adolescente , Adulto , Alopecia Areata/genética , Alopecia Areata/inmunología , Brasil , Estudios de Casos y Controles , Estudios Transversales , Femenino , Frecuencia de los Genes/genética , Antígenos HLA-B/sangre , Antígenos HLA-B/genética , Antígenos HLA-C/sangre , Antígenos HLA-C/genética , Cadenas HLA-DRB1/sangre , Cadenas HLA-DRB1/genética , Antígenos de Histocompatibilidad Clase I/sangre , Antígenos de Histocompatibilidad Clase II/sangre , Humanos , Masculino , Persona de Mediana Edad , Población Blanca , Adulto JovenRESUMEN
Abstract: Background: Alopecia areata (AA) is a common disorder of unknown etiology that affects approximately 0.7% to 3.8% of patients among the general population. Currently, genetic and autoimmune factors are emphasized as etiopathogenic. Studies linking Human Leukocyte Antigens (HLA) to AA have suggested that immunogenetic factors may play a role in the disease's onset/development. Objectives: To investigate an association between AA and HLA class I/II in white Brazilians. Methods: Patients and control groups comprised 33 and 112 individuals, respectively. DNA extraction was performed by column method with BioPur kit. Allele's classification was undertaken using the PCR-SSO technique. HLA frequencies were obtained through direct counting and subjected to comparison by means of the chi-square test. Results: Most patients were aged over 16, with no familial history, and developed partial AA, with no recurrent episodes. Patients showed a higher frequency of HLA-B*40, HLA-B*45, HLA-B*53 and HLA-C*04 compared with controls, although P was not significant after Bonferroni correction. Regarding HLA class II, only HLA-DRB1*07 revealed statistical significance; nevertheless, it featured more prominently in controls than patients (P=0.04; Pc=0.52; OR=0.29; 95%; CI=0.07 to 1.25). P was not significant after Bonferroni correction. Conclusions: The development of AA does not seem to be associated with HLA in white Brazilians, nor with susceptibility or resistance. The studies were carried out in populations with little or no miscegenation, unlike the Brazilian population in general, which could explain the inconsistency found.
Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Adulto Joven , Antígenos de Histocompatibilidad Clase I/genética , Antígenos de Histocompatibilidad Clase II/genética , Brasil , Antígenos de Histocompatibilidad Clase I/sangre , Antígenos HLA-B/genética , Antígenos HLA-B/sangre , Antígenos HLA-C/genética , Antígenos HLA-C/sangre , Antígenos de Histocompatibilidad Clase II/sangre , Estudios de Casos y Controles , Estudios Transversales , Población Blanca , Alopecia Areata/genética , Alopecia Areata/inmunología , Cadenas HLA-DRB1/genética , Cadenas HLA-DRB1/sangre , Frecuencia de los Genes/genéticaRESUMEN
The transporter 1 ATP-binding cassette sub-family B (MDR/TAP) gene (TAP1) is located in the major histocompatibility complex class II region, and forms a heterodimer that plays a key role in endogenous antigen presentation pathways. Investigation of polymorphisms identified in these loci has revealed an association with several autoimmune disorders. Alopecia areata (AA) is a common autoimmune disease resulting from T cell-induced damage to hair follicles. The present study documents for the first time a comparison between the allelic and genotypic frequencies of TAP1 single nucleotide polymorphisms (SNPs) in patients with AA and those of a control group, using a direct sequencing method. Our results suggest an association between a promoter SNP (rs2071480) and susceptibility to this disease.
Asunto(s)
Transportadoras de Casetes de Unión a ATP/genética , Alopecia Areata/genética , Predisposición Genética a la Enfermedad , Folículo Piloso/metabolismo , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Transportador de Casetes de Unión a ATP, Subfamilia B, Miembro 2 , Transportadoras de Casetes de Unión a ATP/inmunología , Adolescente , Adulto , Alelos , Alopecia Areata/etnología , Alopecia Areata/inmunología , Alopecia Areata/patología , Pueblo Asiatico , Estudios de Casos y Controles , Femenino , Expresión Génica , Frecuencia de los Genes , Sitios Genéticos , Folículo Piloso/inmunología , Folículo Piloso/patología , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T/inmunología , Linfocitos T/metabolismo , Linfocitos T/patologíaRESUMEN
Alopecia areata is a disease of the hair follicles, with strong evidence supporting autoimmune etiology. Alopecia areata is frequently associated with immune-mediated diseases with skin manifestations such as psoriasis and lichen planus, or without skin manifestations such as autoimmune thyroiditis and idiopathic thrombocytopenic purpura. Helicobacter pylori (H. pylori) infection is present in around 50% of the world's population and has been associated with a variety of immune-mediated extra-digestive disorders including autoimmune thyroiditis, idiopathic thrombocytopenic purpura, and psoriasis. A case of a 43-year old man with an 8-mo history of alopecia areata of the scalp and beard is presented. The patient was being treated by a dermatologist and had psychiatric support, without any improvement. He had a history of dyspepsia and the urea breath test confirmed H. pylori infection. The patient went into remission from alopecia areata after H. pylori eradication. If such an association is confirmed by epidemiological studies designed for this purpose, new therapeutic options could be available for these patients, especially in areas where infection with H. pylori is highly prevalent.
Asunto(s)
Alopecia Areata/etiología , Infecciones por Helicobacter/complicaciones , Adulto , Alopecia Areata/inmunología , Amoxicilina/uso terapéutico , Antibacterianos/uso terapéutico , Pruebas Respiratorias , Claritromicina/uso terapéutico , Dispepsia/etiología , Dispepsia/microbiología , Inhibidores Enzimáticos/uso terapéutico , Infecciones por Helicobacter/tratamiento farmacológico , Helicobacter pylori , Humanos , Masculino , Omeprazol/uso terapéuticoRESUMEN
La alopecia areata es una enfermedad dermatológica caracterizada por áreas o parches de alopecia con bordes netos en cuero cabelludo (principalmente) y resto del cuerpo. Es no cicatricial y tiene un curso impredecible, incluso la involución espontánea. Corresponde al 2 por ciento de las consultas dermatológicas. Puede asociarse a alteraciones autoinmunes como la tiroiditis de Hashimoto, vitíligo y atopia. Hasta una 20 por ciento de los pacientes tienen antecedentes familiares de la enfermedad. Actualmente puede tratarse con corticoides intralesionales, inmunoterapia tópica o sistémica, antralina, minoxidil y fotoquimioterapia. El tratamiento y la evolución dependen principalmente de dos factores: extensión y la edad de los pacientes.
Asunto(s)
Humanos , Alopecia Areata/diagnóstico , Alopecia Areata/etiología , Alopecia Areata/tratamiento farmacológico , Alopecia Areata/genética , Alopecia Areata/inmunología , Corticoesteroides/uso terapéutico , Diagnóstico Diferencial , Pronóstico , Signos y SíntomasRESUMEN
La alopecía areata es un motivo de consulta habitual, afecta a ambos sexos, su mayor incidencia se encuentra entre los 20 y los 50 años. Se caracteriza por el taque de los folículos pilosos en anágeno. Si bien no es posible definir una causa concreta se reconoce la importancia de los mecanismos autoinmunes. En los últimos años se han logrado importantes avances en lo que se refiere a marcadores genéticos, rol de las citoquinas y en estudios sobre la papila como posible blanco de la enfermedad. Se reseñan los factores genéticos, psicológicos, neurológicos, vasculares e infecciosos presuntamente implicados.
Asunto(s)
Humanos , Alopecia Areata/epidemiología , Alopecia Areata/etiología , Alopecia Areata/genética , Alopecia Areata/inmunología , Alopecia Areata/fisiopatología , Alopecia Areata/psicología , Marcadores GenéticosRESUMEN
La alopecía areata es un motivo de consulta habitual, afecta a ambos sexos, su mayor incidencia se encuentra entre los 20 y los 50 años. Se caracteriza por el taque de los folículos pilosos en anágeno. Si bien no es posible definir una causa concreta se reconoce la importancia de los mecanismos autoinmunes. En los últimos años se han logrado importantes avances en lo que se refiere a marcadores genéticos, rol de las citoquinas y en estudios sobre la papila como posible blanco de la enfermedad. Se reseñan los factores genéticos, psicológicos, neurológicos, vasculares e infecciosos presuntamente implicados. (AU)
Asunto(s)
Humanos , Alopecia Areata/epidemiología , Alopecia Areata/etiología , Alopecia Areata/genética , Alopecia Areata/inmunología , Alopecia Areata/psicología , Alopecia Areata/fisiopatología , Marcadores GenéticosRESUMEN
A Alopecia areata é uma doença comum, para a qual tem-se procurado, desde há muito tempo, uma explicaçäo etiopatogênica satisfatória sem que até o momento se tenha conseguido. Estudamos, no Hospital José Joaquim Aguirre da Faculdade de Medicina da Universidade do Chile, diferentes parâmetros imunológicos em 142 pacientes portadores de Alopecia areata de diferentes graus, procurando explicar uma etiopatogenia imunológica para esta doença. Nossa conclusäo fundamental é que uma clara imunodeficiência celular nestes pacientes, avaliada através de Teste do dinitroclorobenzeno e Teste de Roseta E (linfócitos T x mm3 de sangue periférico). Como objetivo para mais estudos no futuro, acreditamos nos achados conflitantes da imunofluorescência indireta e direta, que avaliamos em 23 e 9 de nossos pacientes, respectivamente