Eficácia do fluconazol subconjuntival na ceratite experimental por Fusarium solani em modelo animal

Efficacy of subconjunctivally injected fluconazole in experimental Fusarium solani keratitis in animal model

RESUMO

Objetivo:

Avaliar a eficácia do uso do fluconazol subconjuntival em ceratite fúngica por Fusarium solani experimentalmente induzida em modelo animal.

Métodos:

Após imunossupressão prévia com corticosteróide subconjuntival, o inóculo padrão, preparado com o auxílio do método de espectrofotometria, foi injetado no estroma corneano. Depois de três dias, iniciou-se a aplicação de 300 μl de fluconazol subconjuntival (grupo 1) ou placebo (grupo 2), por quatro dias consecutivos. Cinco dias após a primeira dose subconjuntival de fluconazol ou placebo, procedeu-se ao sacrifício dos animais e à trepanação das córneas e imersão destas em meio de enriquecimento líquido. Alíqüotas de 100, 10 e 1 μl deste meio foram semeadas, após 3 dias, em placas com Sabouraud-dextrose e as colônias crescidas, contadas em 5 dias.

Resultados:

A análise estatística considerou o número de colônias crescidas nas diferentes diluições, para cada grupo. Não houve diferença estatisticamente significante entre o grupo tratado com fluconazol subconjuntival e o grupo controle.

Conclusão:

A utilização de fluconazol subconjuntival, durante 4 dias, não foi eficaz na redução do número de colônias crescidas em placas, quando comparado com o grupo tratado apenas com placebo, em ceratite fúngica por Fusarium solani experimentalmente induzida em coelhos.

Palavras-chave:
Fluconazol; Micose; Ceratite; Fungo; Fusarium

SUMMARY

Purpose:

To assess whether subconjunctivally injected fluconazole was effective in experimental Fusarium solani keratomycosis in rabbits.

Methods:

After corticosteroid immuno supression of the rabbit eyes, 20 μ1 of the inoculum, prepared by the spectrophotometric method, were injected into the midcorneal stroma. Three days later, either 300 μ1 subconjuntival fluconazole or placebo injections were initiated and given during four consecutive days. After five days of the first dose, the animals were sacrified and the corneas trephined and immersed in appropriate liquid growth media. Aliquots of 100, 10 and 1 μl were placed in ágar-Sabouraud-dextrose medium plates and the growth of F. solani determined by counting the number of colonies grown in the plates after 5 days.

Results:

Statistical analysis considered the number of colonies in the different dillutions, for each group. There was no statistical significant difference between the fluconazole-treated group and the placebo group.

Conclusion:

The present investigation did not find any significant reduction in the number offungal colonies grown in plates, after administration ofsubconjunctival fluconazole during 4 consecutive days, when compared to the placebo-treated group, in cases of experimentally induced F. solani keratitis in rabbits.

Keywords:
Fluconazole; Mycosis; Keratitis; Fungus; Fusarium

Texto completo disponível apenas em PDF.

• Apresentado como tema-livre durante o XXIX Congresso Brasileiro de Oftalmologia.
• Trabalho realizado com apoio financeiro do CAPES.

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Datas de Publicação

• Publicação nesta coleção
  Oct 1998