RESUMO
Darwinian medicine, or evolutionary medicine, regards some pathological conditions as attempts by the organism to solve a problem or develop defense mechanisms. At certain stages of human evolution, some diseases may have conferred a selective advantage. Psoriasis is a high-penetrance multigenic disorder with prevalence among whites of up to 3%. Psoriatic lesions have been linked with enhanced wound-healing qualities and greater capacity to fight infection. Leprosy, tuberculosis, and infections caused by viruses similar to human immunodeficiency virus have been postulated as environmental stressors that may have selected for psoriasis-promoting genes in some human populations. The tendency of patients with severe psoriasis to develop metabolic syndrome may reflect the body's attempt to react to environmental stresses and warning signs by triggering insulin resistance and fat storage.
Assuntos
Evolução Biológica , Aptidão Genética , Psoríase/genética , Adaptação Biológica , Peso ao Nascer , Metabolismo Energético , Etnicidade/genética , Interação Gene-Ambiente , Predisposição Genética para Doença , Humanos , Síndrome Metabólica/etiologia , Penetrância , Psoríase/complicações , Psoríase/epidemiologia , Psoríase/fisiopatologia , Seleção Genética , Dermatopatias Infecciosas/genética , Dermatopatias Infecciosas/prevenção & controle , CicatrizaçãoRESUMO
Conventional methods, including microscopy, culture, and serologic studies, are a mainstay in the diagnosis of cutaneous infection. However, owing to limitations associated with these techniques, such as low sensitivity for standard microscopy and in the case of culture delay in diagnosis, polymerase chain-reaction based molecular techniques have taken on an expanding role in the diagnosis of infectious processes in dermatopathology. In particular, these assays are a useful adjunct in the diagnosis of cutaneous tuberculosis, atypical mycobacterial infection, leprosy, Lyme disease, syphilis, rickettsioses, leishmaniasis, and some fungal and viral infections. Already in the case of tuberculosis and atypical mycobacterial infection, standardized polymerase chain-reaction assays are commonly used for diagnostic purposes. With time, additional molecular-based techniques will decrease in cost and gain increased standardization, thus delivering rapid diagnostic confirmation for many difficult-to-diagnose cutaneous infections from standard formalin-fixed paraffin-embedded tissue specimens.
Assuntos
Reação em Cadeia da Polimerase/métodos , Dermatopatias Infecciosas/diagnóstico , Dermatomicoses/diagnóstico , Dermatomicoses/microbiologia , Humanos , Leishmaniose Cutânea/diagnóstico , Hanseníase Virchowiana/diagnóstico , Hanseníase Virchowiana/microbiologia , Doença de Lyme/diagnóstico , Doença de Lyme/microbiologia , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Dermatopatias Infecciosas/genética , Sífilis Cutânea/diagnóstico , Sífilis Cutânea/microbiologia , Tuberculose Cutânea/diagnóstico , Tuberculose Cutânea/microbiologia , Viroses/diagnóstico , Viroses/virologiaRESUMO
BACKGROUND: In the pre-microbiological era, it was widely accepted that diseases, today known to be infectious, were hereditary. With the discovery of microorganisms and their role in the pathogenesis of several diseases, it was suggested that exposure to the pathogen was enough to explain infection. Nowadays, it is clear that infection is the result of a complex interplay between pathogen and host, therefore dependant on the genetic make-up of the two organisms. Dermatology offers several examples of infectious diseases in different stages of understanding of their molecular basis. In this review, we summarize the main advances towards dissecting the genetic component controlling human susceptibility to infectious diseases of interest in dermatology. Widely investigated diseases such as leprosy and leishmaniasis are discussed from the genetic perspective of both host and pathogen. Others, such as rare mycobacterioses, fungal infections and syphilis, are presented as good opportunities for research in the field of genetics of infection.
Assuntos
Predisposição Genética para Doença/genética , Interações Hospedeiro-Patógeno/genética , Dermatopatias Infecciosas/genética , Histoplasmose/genética , Humanos , Leishmania/genética , Leishmaniose/genética , Hanseníase/genética , Mycobacterium leprae/genética , Paracoccidioidomicose/genética , Fatores de Risco , Sífilis Cutânea/genética , Tuberculose Cutânea/genéticaRESUMO
BACKGROUND: In the pre-microbiological era, it was widely accepted that diseases, today known to be infectious, were hereditary. With the discovery of microorganisms and their role in the pathogenesis of several diseases, it was suggested that exposure to the pathogen was enough to explain infection. Nowadays, it is clear that infection is the result of a complex interplay between pathogen and host, therefore dependant on the genetic make-up of the two organisms. Dermatology offers several examples of infectious diseases in different stages of understanding of their molecular basis. In this review, we summarize the main advances towards dissecting the genetic component controlling human susceptibility to infectious diseases of interest in dermatology. Widely investigated diseases such as leprosy and leishmaniasis are discussed from the genetic perspective of both host and pathogen. Others, such as rare mycobacterioses, fungal infections and syphilis, are presented as good opportunities for research in the field of genetics of infection.
INTRODUÇÃO: Durante a era pré-microbiológica, era comum a visão de que doenças, hoje sabidamente infecciosas, eram hereditárias. Com a descoberta dos microorganismos e seu papel na patogênese de diversas patologias, chegou-se a propor que a exposição ao patógeno era condição suficiente para explicar infecção. Hoje, está claro que infecção é o resultado de uma complexa interação entre patógeno e hospedeiro, dependendo portanto, em última análise, do make-up genético de ambos os organismos. A dermatologia oferece diversos exemplos de doenças infecciosas em diferentes graus de entendimento de suas bases moleculares. Nesta revisão, resumimos os principais avanços na direção da dissecção do componente genético controlando suscetibilidade do ser humano a doenças infecciosas de importância na dermatologia. Doenças amplamente estudadas, como a hanseníase e a leishmaniose, são discutidas sob o ponto de vista da genética tanto do hospedeiro quanto do patógeno. Outras, como micobacterioses raras, micoses e sífilis, são apresentadas como boas oportunidades para pesquisa na área de genética de infecção.