Photodynamic inactivation of in vitro bacterial cultures from pressure ulcers.

Abstract

PURPOSE:

To evaluate in vitro the antibacterial effect of diode laser light of wavelength 650 nm, in association with the photosensitive substance toluidine blue, on the bacteria in infected skin ulcers.

METHODS:

Samples were collected by means of swabs containing a medium for transporting infected material from skin ulcers. The material was inoculated into culturing medium containing azide blood agar for the growth of Gram-positive bacteria, and MacConkey agar for Gram-negative bacteria, and incubated for 48 hours. The results obtained from counting the colony-forming units were correlated and subjected to statistical analysis, adopting the significance level of p > or = 0.05.

RESULTS:

From analysis of variance (ANOVA), the result for the general mean was p = 0.0215. Using the t test with post-hoc test, the result for TBO vs. Control was p = 0.0186, and for TBO + Laser vs. Control it was p = 0.0039.

CONCLUSION:

There was a significant reduction in colony-forming units when the cultures were subjected to photodynamic therapy.

• Authors: Paulo de Tarso Camillo de Carvalho, Ana Paula da Costa Marques, Felipe Abdalla dos Reis, Ana Carulina Guimarães Belchior, Iandara Schettert Silva, Carlos Alexandre Habitante, Daniela Aparecida Sussai
• Journal: Acta cirurgica brasileira (Acta Cir Bras) Vol. 21 Suppl 4 Pg. 32-5 ( 2006) ISSN: 0102-8650 [Print] Brazil
• PMID: 17293963 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Photosensitizing Agents
• Tolonium Chloride

Topics

• Analysis of Variance
• Colony Count, Microbial
• Gram-Negative Bacteria (radiation effects)
• Gram-Positive Bacteria (radiation effects)
• Humans
• Lasers, Semiconductor (therapeutic use)
• Low-Level Light Therapy
• Photochemotherapy
• Photosensitizing Agents (pharmacology, therapeutic use)
• Pressure Ulcer (drug therapy, microbiology, radiotherapy)
• Tolonium Chloride (pharmacology)