Abstract BACKGROUND: Psoriasis is an immune-mediated disease that manifests predominantly in the skin, although systemic involvement may also occur. Although associated comorbidities have long been recognized and despite several studies indicating psoriasis as an independent risk factor for cardiovascular events, little has been done in general medical practice regardind screening. In the United States, less than 50% of clinicians are aware of these recommendations. OBJECTIVE: To identify the prevalence of these comorbidities in 296 patients followed up at a university dermatology clinic. METHODS: Systematically investigated comorbidity frequencies were compared with general practitioners' registry frequencies. Clinical features correlated with comorbidities were also investigated. RESULTS: High prevalences of systematically investigated comorbidities such as hypertension (30%) and dyslipidemia (26.5%) were documented. Conversely, data from general practitioners' records showed that 33% of dyslipidemia cases were undiagnosed and indicated possible underdiagnosis of some comorbidities. Furthermore, an association was found between: the number of comorbidities and psoriasis duration, age and high body mass index an association was found between the number of comorbidities and psoriasis duration, age, high body mass index, waist circumference or waist-to-hip ratio. (p<0.05). CONCLUSION: Disease duration, age and high body mass index, waist circumference or waist-to-hip ratio are possible criteria for choosing which patients should be screened for comorbidities. Underdiagnosis of comorbidities by general practitioners highlights the need for a multidisciplinary approach in psoriasis management.

Estudos recentes demonstram uma relação entre obesidade e inflamação crônica, confirmada através da associação de níveis elevados de fator de necrose tumoral alfa (TNF-±), interleucina seis (IL-6) e proteína C reativa, com aumento do índice de massa corporal (IMC). O estado inflamatório, nos indivíduos obesos, poderia contribuir para o desenvolvimento ou agravamento da psoríase. Fenômenos análogos já foram descritos, em outras doenças inflamatórias crônicas, como a artrite reumatóide e doença de Chrön. Estudos epidemiológicos mostram uma prevalência elevada de comorbidades cardiovasculares, secundárias às alterações metabólicas, associadas à psoríase e obesidade. Permanecem ainda não elucidados alguns aspectos desta associação, como: o impacto da obesidade (nas formas clínicas da dermatose, na associação com comorbidades e na resposta ao tratamento).

Recent studies have found a relationship between obesity and chronic inflammation, confirmed by the association of high levels of tumor necrosis factor (TNF-_), interleukin six (IL-6,) and reactive C-protein with an increase in body mass index (BMI). In obese individuals, this inflammatory condition could contribute to the development or aggravation of psoriasis. Analogous phenomena have already been described in other inflammatory chronic diseases, such as rheumatoid arthritis and Crohn's disease. Epidemiological studies have identified a high prevalence of cardiovascular comorbidities, secondary to the metabolic alterations associated with psoriasis and obesity. A few aspects of this association remain unclear, such as the impact of obesity in the clinical forms of dermatoses, in the response to treatment, and its relationship with comorbidities.

A participação do sistema de histocompatibilidade humano (HLA: human leukocyte antigens) na patogênese das doenças auto-imunes é bem conhecida. Situado no braço curto do cromossomo 6, o sistema HLA se destaca por seu polimorfismo e por sua capacidade de conferir susceptibilidade ou proteção a diferentes enfermidades. Em Dermatologia, esse sistema desempenha papel importante na patogenia e história natural de várias doenças. A força e o tipo de associação variam com a dermatose e, algumas vezes, com o grupo étnico-racial estudado. O surgimento de métodos moleculares para tipificação dos alelos HLA e as recentes atualizações de sua nomenclatura têm contribuído para o melhor entendimento desse sistema. Infelizmente, essas informações não têm sido veiculadas de maneira adequada na literatura clínica, o que dificulta o entendimento da associação do HLA com as doenças cutâneas. Nesta revisão, são discutidos alguns aspectos do sistema HLA, métodos de detecção, nomenclatura e sua associação com vitiligo, pênfigo, psoríase, lúpus eritematoso, escabiose, leishmaniose cutânea, hanseníase, paracoccidioidomicose e dermatite atópica.

The participation of the human histocompatibility system (HLA: human leukocyte antigens) in the pathogenesis of autoimmune diseases is well known. Situated on the short arm of chromosome 6, the HLA system is very polymorphic and has the capacity to confer susceptibility or resistance to different diseases. In Dermatology, this system has an important participation in the pathogenesis and natural course of various diseases. The strength and type of association differ with conditions and sometimes with the ethnic-racial group studied. The discovery of molecular methods to typify HLA alleles and recent updates in its nomenclature has contributed to a better understanding of this system. Unfortunately, this information has not been adequately transmitted in the literature, hindering identification of the association of the HLA with skin diseases. In this review, some aspects of the HLA system are discussed, such as methods of detection, nomenclature and association with vitiligo, pemphigus, psoriasis, lupus erythematosus, scabies, cutaneous Leishmaniasis, leprosy, paracoccidiodomycosis and atopic dermatitis.