The antimicrobial effect of acetic acid—An alternative to common local antiseptics?

Acetic acid has been commonly used in medicine for more than 6000 years for the disinfection of wounds and especially as an antiseptic agent in the treatment and prophylaxis of the plague. The main goal of this study was to prove the suitability of acetic acid, in low concentration of 3%, as a local antiseptic agent, especially for use in salvage procedures in problematic infections caused by organisms such as Proteus vulgaris, Acinetobacter baumannii or Pseudomonas aeruginosa.This study was designed to compare the in vitro antimicrobial effect of acetic acid with those of common local antiseptics such as povidone–iodine 11% (Betaisodona®), polyhexanide 0.04% (Lavasept®), mafenide 5% and chlohexidine gluconate 1.5% cetrimide 15% (Hibicet®). Former studies suggest the bactericidal effect of acetic acid, but these data are very heterogeneous; therefore, a standardised in vitro study was conducted.To cover the typical bacterial spectrum of a burn unit, the following Gram-negative and Gram-positive bacterial strains were tested: Escherichia coli, P. vulgaris, P. aeruginosa, A. baumannii, Enterococcus faecalis, Staphylococcus epidermidis, methicillin-resistant Staphylococcus aureus (MRSA) and β-haemolytic Streptococcus group A and B.The tests showed excellent bactericidal effect of acetic acid, particularly with problematic Gram-negative bacteria such as P. vulgaris, P. aeruginosa and A. baumannii. The microbiological spectrum of acetic acid is wide, even when tested at a low concentration of 3%. In comparison to our currently used antiseptic solutions, it showed similar – in some bacteria, even better – bactericidal properties. An evaluation of the clinical value of topical application of acetic acid is currently underway. It can be concluded that acetic acid in a concentration of 3% has excellent bactericidal effect and, therefore, seems to be suitable as a local antiseptic agent, but further clinical studies are necessary.