Isadora Meyer

Immunogenetics and infectious diseases: special reference to the mayor histocompatibility complex.

Many studies have tried to identify genetic markers for infectious diseases, some of them have focused on human leukocyte antigens (HLA). The products of HLA genes interact with surface-specific receptors of T lymphocytes, resulting in activation of the hosts immune response. Association of bacterial, viral, parasitic and fungal infections with the hosts HLA has been widely investigated. The type and strength of this association differs among distinct populations, as well as among racial and/or ethnic groups. The new molecular methods for the identification of the HLA alleles, and the resulting new nomenclature, have contributed to a better understanding of this system. Unfortunately, this information has not been adequately transmitted to clinicians, which hampers the understanding of the association between the HLA system and diseases. We revised relevant studies on the association of HLA genes with infectious diseases, demonstrating their importance in the pathogenic mechanisms, through increased susceptibility or protection against infections and their complications.

Distribuição e freqüência de alelos e haplotipos HLA em brasileiros com diabetes melito tipo 1

The genetic predisposition to type 1 diabetes (DM1) is associated with genes of the human leukocyte antigen (HLA) system, specially the HLA-DR and -DQ. In Caucasians, the HLA-DR3 and -DR4 antigens are associated with susceptibility and the -DR2, with protection. In Brazil, a country with a large miscegenation of Europeans Caucasians, Native Amerindians and African Blacks, the genetic basis of DM1 has not been adequately studied. The aim of this paper is to present a critical review of articles indexed in the MEDLINE and LILACS-BIREME data basis about the association of HLA with DM1 in Brazilians. Eight papers, all of them from the Southeast region, were found. Immunogenetic susceptibility to DM1 in Brazilians was associated with HLA-DRB1*03, -DRB*04, -DQB1*0201, -DQB1*0302 alleles, and protection against DM1 was associated with HLA-DQB1*0602, -DQB1*0301 alleles and -DR2 and -DR7 antigens. Since the Brazilian population is not racially homogeneous, it is not possible to extrapolate studies from a single region to the remaining of the country. It is necessary to study populations from different regions to identify new associations or to strengthen associations with the ones already identified. This knowledge will contribute to future prophylactic or therapeutic interventions in the group of Brazilians at risk of developing DM1.

Antígenos de histocompatibilidade humanos e dermatologia: da pesquisa para a prática clínica

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.

Associação do sistema de histocompatibilidade humano com doenças oftalmológicas

Many studies have been trying to identify genetic markers for ophthalmological diseases, including, among others, the HLA (Human Leukocyte Antigens). Localized on the short arm of chromosome 6, the human leukocyte antigen system is well known for its capacity to confer susceptibility or resistance to different diseases. In view of its accentuated polymorphism, the strength and type of association differs with the disease and sometimes, with the studied ethnic-racial group. The development of molecular methods to typify HLA alleles and recent updates of their nomenclature has contributed to a better understanding of this system. In this review, some aspects of the human leukocyte antigen system are discussed, such as the methods of detection, nomenclature and association with acute anterior uveitis, ocular cicatricial pemphigoid, young-onset keratoconus and birdshot retinochoroidopathy.

Anomalia de Peters, seus aspectos clínicos e terapêuticos: relato de caso

Peters anomaly consists in the most common congenital corneal opacity related to a malformation of the anterior segment of the eye. Its main characteristics are central leukoma and iridocorneal adherences at the area affected by the leukoma. It can be identified isolated or in association with other ocular or systemic abnormalities, and the prognostic tend to be worse in the latter cases. The etiology of Peters anomaly remains uncertain, but the most likely causes are related to genetic, infectious, traumatic and toxic factors. A range of possible treatment strategies exists, though the effectiveness of each of them depends on how the disease occurs and whether it is identified in early or advanced stages - the earlier the diagnosis, the higher the possibility of a successful intervention, given that precocious treatments are more likely to result in a good development of the vision. This work reports a case of Peters anomaly that was diagnosed in an advanced stage, discussing the characteristics of the case and treatment possibilities.

Schwannoma em pálpebra superior esquerda em criança de 10 anos

Schwannoma is a rare benign neurogenic tumor whose origins come from Schwann cells located at the myelin sheath of peripheral nerves. It is frequently associated with the orbit, but ocular tissues in general and eyelids in particular are very rarely affected. There are very few reports that can be found in the Literature describing eyelid schwannomas and we have found only two articles describing it affecting children. To our knowledge, this is the first case report about eyelid schwannoma in Brazil and it involves a child.Schwannoma is a rare benign neurogenic tumor. It arises from Schwann cells located at the myelin sheath of peripheral nerves. Its incidence is frequently associated with the orbit. Ocular tissues in general and eyelids in particular are rarely affected. Very few reports can be found in the literature describing eyelid schwannomas. Amongst these, we have found only two describing it affecting children. To our knowledge, this is the first case report about eyelid schwanomma in Brazil - and it involves a child.

Complexo principal de histocompatibilidade: sua participação na patogênese das doenças reumáticas auto-imunes - doi:10.5020/18061230.2006.p155

In order to allow early diagnosis and more efficient treatments, many studies have been trying to define genetic markers of rheumatic diseases. Amongst them, antigens and alleles of the HLA (Human Leukocyte Antigens) system are distinguished. Located in the short arm of chromosome 6, the HLA system exerts genetic influence on the susceptibility and severity of these diseases. The discovery of new molecular methods to typify HLA alleles and the recent nomenclature updates have been contributing to a better understanding of this system. Unfortunately, this information has not been adequately published in the clinical literature. The present work aimed at presenting the function, nomenclature and methods of detection of the HLA polymorphism; and to review its associations with rheumatic fever, systemic erythematosus lupus, rheumatoid arthritis, juvenile idiopathic arthritis and spondyloarthropathies. Articles that were published between 1980 and 2005 were searched in the MEDLINE and LILACS data basis. This review demonstrated that although the HLA association is well established for some rheumatic diseases (e.g., HLA-B27 and spondyloarthropathies, HLA DR-3 and HLA-DR4 with rheumatoid arthritis, HLA-DR4 and lupus) others vary in different ethnic-racial group and illnesses, due to its polymorphism. It is necessary to study populations from different ethnic backgrounds to identify new associations or to strengthen associations with the ones already identified. This knowledge will contribute to future prophylactic or therapeutic interventions in patients with rheumatic disorders or at risk to develop them.

Tumor metastático uveal: revisão de literatura sobre a neoplasia ocular maligna mais comum

Choroid metastasis have been considered the most common ocular malignancy. Early detection allows arrangements to provide tumor reduction and to improve visual quality. Many treatments have been proposed to aim these objectives. This work reviews clinical characteristics, diagnosis and monitoring methods, characteristics of complementary exams, and treatments used in patients with this disease.

Retinocoroidite toxoplásmica reativada provavelmente por cirurgia refrativa: laser in situ keratomileusis - LASIK

O presente trabalho objetiva demonstrar provavel relaco entre recorrencia de toxoplasmose ocular e cirurgia refrativa (LASIK). Trata-se de relato de caso de um paciente de 33 anos de idade com recorrencia de retinocoroidite toxoplasmica apos cirurgia de LASIK. O exame fundoscopico do olho esquerdo revelou foco de retinocoroidite em atividade, satelite a cicatriz antiga de toxoplasmose ocular, 17 dias apos cirurgia de LASIK. Os autores apresentam subsidios para o estabelecimento de relacao causal entre LASIK e a reativacao de retinocoroidite toxoplasmatica.