Tratamento de queimadura de segundo grau superficial em face e pescoço com heparina tópica: estudo comparativo, prospectivo e randomizado / Treatment of superficial second degree burn of face and neck with topical heparin: a comparative, prospective and randomized study

INTRODUÇÃO: Novas opções terapêuticas para o tratamento de lesões térmicas são constantemente buscadas, especialmente se reduzirem tempo de cicatrização e dor, sem aumentar as taxas de infecção das queimaduras. Estudos recentes sugerem que o uso tópico de heparina pode alcançar esses objetivos. Este estudo tem o objetivo de avaliar tempo de epitelização, dor e taxa de infecção, comparando o uso de heparina tópica ao uso de colagenase no tratamento de queimadura de segundo grau superficial de face e pescoço. MÉTODO: No total, 20 pacientes foram randomizados em dois grupos: grupo tratado com heparina sódica e grupo tratado com colagenase (controle). Os critérios de exclusão foram: história de sangramento, discrasia sanguínea, alergias ao produto, úlcera péptica ativa e queimadura há mais de 24 horas. O teste de Mann-Whitney foi utilizado para avaliar os resultados. A dor foi avaliada pela necessidade do uso de analgésicos opioides. RESULTADOS: A heparina não foi efetiva em diminuir o tempo de epitelização ou o uso de opioides, e a taxa de infecção não apresentou diferença estatística entre os grupos. CONCLUSÕES: A heparina pode ser usada com segurança no tratamento de queimadura de segundo grau superficial em face e pescoço, mas seus efeitos benéficos ainda precisam ser comprovados.

BACKGROUND: New treatment options for thermal injuries are very desirable, especially if they reduce healing time and pain without increase of infection rates. Recent studies suggest that heparin topical use can achieve those goals. This study has the objective to evaluate healing time, pain and infection rate comparing topical use of heparin and collagenase in the treatment of superficial second degree burns of face and neck. METHODS: Twenty patients were randomized into 2 groups: group treated with topical heparin and group treated with collagenase (control group). The exclusion criteria were: history of bleeding, blood discrasia, allergies to the product, active peptic ulcer and burns with more than 24 hours. Mann-Whitney test was applied to evaluate the results. The pain was measured by the use of opioid analgesics. RESULTS: The heparin was not effective in decrease of healing time nor the use of opioids, and the infection rate didn't present significant difference between the groups. CONCLUSIONS: The heparin can be used safely in treatment of superficial second degree burn of face and neck, but its beneficial effects need to be proven.

Interferon-gamma upregulates the stromelysin-1 gene expression by human skin fibroblasts in culture

The equilibrium between deposition and degradation of extracellular matrix(ECM) is essential to normal tissue development and repair of wound or inflammatory responses. It has recently become apparent that several cytokines and growth factors are capable of modulating fibroblast proliferation and biosynthetic activity. To understand the role of these factors in connective tissue regulation, we examined the effect of interferon-gamma (IFN-gamma) on stromelysin-1 gene expression in cultured human dermal fibroblasts. The steady-state levels of stromelysin-1 mRNA were increased in IFN-gamma treated cultured dermal fibroblasts. In the CAT assay, the stromelysin-1 promoter activity was increased 2.8-fold compared with untreated control. Therefore IFN-gamma stimulates the stromelysin-1 promoter activity, resulting in transcriptional enhancement of gene expression. Transforming growth factor-beta (TGF-beta) showed the antagonistic action to the effects of IFN-gamma in cultured dermal fibroblasts. Furthermore, gel mobility shift assays demonstrated enhanced AP-1 binding activities in nuclear extracts from cells incubated with IFN-gamma. These data suggest that IFN-gamma is an up-regulator and TGF-beta is a down regulator on the stromelysin-1 gene expression, respectively, and the AP-1 binding site may be necessary for gene response.