Uso da terapia fotodinâmica antimicrobiana (aPDT) com azul de metileno em estudos de modelos animais: revisão sistemática

Abstract

Antimicrobial photodynamic therapy (aPDT) is a minimally invasive alternative therapy used to treat infectious diseases, which allows the elimination of fungi and bacteria. If, on the one hand, aPDT is increasingly studied, on the other there is still doubt about the level of evidence of the published results, either due to the difficulty in analysing the different values of each parameter or the parameters themselves. Thus, the objective of this study is to carry out a systematic review on the use of aPDT with methylene blue (MB) in animal models whose outcomes have been microbiological quantification. Studies published in the electronic databases of MEDLINE, Embase, Opengrey and LILACS were reviewed from 1995 to 2020, in English, Portuguese, French, Italian and Spanish. After the initial search, 1842 studies related to the topic were found and of these, 21 were included for data extraction, adding up to a total of 550 animals studied, all being controlled studies, 07 randomized and 03 blinded. About 12 studies evaluated skin infections, 03 by Leishmania amazonensis, 07 by bacterial infections and 02 by fungus; 02 studies evaluated vaginal candidiasis; 02 studies evaluated pyogenic arthritis; 01 study evaluated onychomycosis; 01 study trichomoniasis vaginal; 01 study evaluated bacterial cystitis; 01 study evaluated fungal keratitis and 01 study evaluated baterial rhinosinusitis. Discussion and conclusions: The most promising data refer to onychomycosis, vaginal candidiasis, and bacterial or Leishmania Tegumentar’s. skin infections. No animal adverse effects of aPDT were reported suggesting that aPDT is a safe technique when applied in a controlled manner, under supervision, and in superficial infections. Regarding MB and light parameters, the better quality studies show lasers, light emitting diode (LED) and lamps used, always encompassing the red wavelength, being compatible with MB; irradiances ranged from 3.3 to 50 W/cm2; radiant exposures ranged from 6 to 360 J / cm2, and irradiation times ranged from 85,6 s to 60 min. The enormous variability of the protocols used did not allow us to perform a quantitative analysis / meta-analysis.