Evaluation of the profile of inflammatory cytokines, through immunohistochemistry, in the skin of patients with allergic contact dermatitis to nickel in the acute and chronic phases

Abstract: Background: Allergic contact dermatitis to ion nickel (Ni+2) is an inflammatory dermatosis, common in industrialized countries. It involves the activation of nickel-specific T-cells, followed by proliferation and induction of a mixed profile of both proinflammatory and regulatory cytokines, suggesting that several T-cell subtypes (helper - Th and cytotoxic - Tc) are involved. A broader understanding of the cytokine profile may lead to new therapeutic approaches. Objectives: This study aimed to analyze the cytokines TNF-α, INF-γ, IL-2, IL-4, IL-10, IL-13, IL-17 and IL-23 using the immunohistochemistry technique in order to try to identify their prevalence in chronic and acute eczema of patients with allergic contact dermatitis to Ni+2. Methods: We performed an immunohistochemical study for eight cytokines in 20 patients with Ni+2 allergic contact dermatitis, biopsied at the site of chronic eczema, triggered by the patient's daily contact with Ni+2, and at the site of acute eczema caused by nickel sulfate, 48 hours after applying the contact test. Results: The stained samples showed positive results for the eight cytokines studied. TNF-α, IFN-γ, IL-4, IL-13 and IL-17 had a higher prevalence in chronic eczema, IL-2 and IL-23 in acute eczema, and IL-10 presented a similar prevalence in both acute and chronic eczema. However, these prevalences were statistically significant only for IL-4 and IL-13. Study Limitations: Small sample size. Conclusions: In chronic and acute eczema, we observed the presence of a mixed cytokine profile of the T cell subtypes (Th/Tc), suggesting that the responses are expressed at the same time.

Innate immunity and effector and regulatory mechanisms involved in allergic contact dermatitis

Abstract: Skin's innate immunity is the initial activator of immune response mechanisms, influencing the development of adaptive immunity. Some contact allergens are detected by Toll-like receptors (TLRs) and inflammasome NLR3. Keratinocytes participate in innate immunity and, in addition to functioning as an anatomical barrier, secrete cytokines, such as TNF, IL-1β, and IL-18, contributing to the development of Allergic Contact Dermatitis. Dendritic cells recognize and process antigenic peptides into T cells. Neutrophils cause pro-inflammatory reactions, mast cells induce migration/maturation of skin DCs, the natural killer cells have natural cytotoxic capacity, the γδ T cells favor contact with hapten during the sensitization phase, and the innate lymphoid cells act in the early stages by secreting cytokines, as well as act in inflammation and tissue homeostasis. The antigen-specific inflammation is mediated by T cells, and each subtype of T cells (Th1/Tc1, Th2/Tc2, and Th17/Tc17) activates resident skin cells, thus contributing to inflammation. Skin's regulatory T cells have a strong ability to inhibit the proliferation of hapten-specific T cells, acting at the end of the Allergic Contact Dermatitis response and in the control of systemic immune responses. In this review, we report how cutaneous innate immunity is the first line of defense and focus its role in the activation of the adaptive immune response, with effector response induction and its regulation.

Pênfigo foliáceo endêmico refratário na adolescência: sucesso terapêutico com imunoglobulina intravenosa / Refractory endemic pemphigus foliaceous in adolescence successfully treated with intravenous immunoglobulin

O Pênfigo Foliáceo Endêmico é doença bolhosa autoimune crônica da pele. Geralmente, o tratamento com prednisona tem excelente resposta, mas existem formas refratárias, sendo necessária terapêutica alternativa. Apresentamos paciente adolescente masculino, com diagnóstico clínico-patológico de pênfigo foliáceo, com forma clínica eritrodérmica grave e refratária a várias terapêuticas, que apresentou evolução satisfatória com imunoglobulina intravenosa. Destaca-se, neste relato, o fato de tratar-se de um paciente adolescente que obteve melhora clínica substancial com imunoglobulina intravenosa e remissão completa da doença, após o quarto ciclo da medicação, possibilitando redução da dose do corticoide e de seus efeitos colaterais.

Endemic Pemphigus Foliaceous is a chronic autoimmune bullous skin disease. Treatment with prednisone often produces excellent results, but resistant forms exist, requiring alternative therapy. Alternative treatments have been used in cases of corticosteroid-refractory pemphigus, showing favorable results. This case study focuses on an adolescent male with a clinical-pathological diagnosis of pemphigus foliaceous with a severe clinical form of erythrodermis, unresponsive to multiple therapies, but which showed a satisfactory outcome with intravenous immunoglobulin. In this case we highlight the fact that the patient was a teenager who showed substantial clinical improvement as the result of using intravenous immunoglobulin, followed by complete remission after the fourth cycle of medication, allowing reduced doses of steroids and a consequent reduction of side effects.

Pênfigo foliáceo endêmico: características sociodemográficas e incidência nas microrregiões do estado de Goiás, baseadas em estudo de pacientes atendidos no Hospital de Doenças Tropicais, Goiânia, GO / Endemic pemphigus foliaceus: social and demographical characteristics and incidence in the microregions of Goias, based on patients seen at the Tropical Diseases Hospital, Goiania, Goias

Fundamento: o pênfigo foliáceo endêmico é doença auto-imune, cutânea, bolhosa, com incidência maior na região Centro-Oeste do Brasil e menor em alguns países sul-americanos. Embora tenha sido demonstrado seu caráter auto-imune pela presença de auto-anticorpos e a importância da predisposição genética, não estão ainda claramente estabelecidos os fatores ambientais intervenientes