Avaliação in vitro da ação antimicrobiana do cloridrato de procaína associado ou não ao bicarbonato de sódio sobre patógenos causadores de infecção urinária

Abstract

Urinary tract infection is a commonly diagnosed disease in companion animals, being responsible for a wide number of antimicrobial prescriptions. Escherichia coli, Proteus mirabilis and Staphylococcus aureus are microorganisms involved the most in urinary tract infections in dogs. The rise of multi-resistant bacteria to antimicrobials is growing in recent decades, being an alarming problem in the world scenario. Alternative treatment with new substances is already a reality. Local anesthetics have also the function of being antimicrobial. The objective of this study was to evaluate the antimicrobial action in vitro of 0.7% procaine hydrochloride associated or not with sodium bicarbonate on pathogens that cause urinary tract infections in dogs and cats. For this, standard strains of Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Proteus mirabilis ATCC 25933 were used. A solution of 0.7% procaine hydrochloride, 0.023% sodium bicarbonate, and 0.7% procaine hydrochloride mixed with 0.023% sodium bicarbonate, were tested using broth dilution and disk-diffusion (antibiogram) methods to verify their antimicrobial actions. The tests were performed in triplicates with positive and negative controls. Staphylococcus aureus showed no growth in the broth dilution test with 0,7 % procaine hydrochloride, procaine hydrochloride associated with sodium bicarbonate and sodium bicarbonate, while Escherichia coli and Proteus mirabilis had bacterial growth. In antibiogram, halos were formed with all three bacteria, Staphylococcus aureus formed a halo with all solutions (0.7% procaine hydrochloride, procaine hydrochloride associated with sodium bicarbonate and sodium bicarbonate), Proteus mirabilis formed a halo in two solutions (0.7% procaine hydrochloride and the association of procaine hydrochloride with sodium bicarbonate) and Escherichia coli formed a halo only with 0.7% procaine hydrochloride solution. Accordingly to this study, 0.7% procaine hydrochloride solution has demonstrated having antimicrobial action against all three strains of bacteria Escherichia coli, Proteus mirabilis and Staphylococcus aureus, whilst sodium bicarbonate alone had antimicrobial action with Staphylococcus aureus. The association of procaine hydrochloride and sodium bicarbonate had action only with Staphylococcus aureus and Proteus mirabilis, having no effect on Escherichia coli.