Pseudomonas infection of the catheter exit site successfully managed with topical acetic acid

A First-in-Human Randomized Clinical Study Investigating the Safety and Tolerability of Stabilized Hypochlorous Acid in Patients with Chronic Leg Ulcers

Objective: Biofilm infections in chronic wounds are common and pose a significant clinical challenge. This challenge was addressed by developing the SoftOx Biofilm Eradicator (SBE) composed of hypochlorous acid (HOCl) and acetic acid with strong broad-spectrum antimicrobial activity. Approach: First-in-human study investigating the safety and tolerability as primary endpoints and wound size effect and antimicrobial efficacy as secondary endpoints of SBE treatment in chronic leg wound patients. The study was divided into two as follows: a randomized, double-blinded, Single Ascending Dose (SAD) phase (n = 16 SBE; n = 4 placebo), where patients were treated with SBE or saline (placebo) only once, followed by an open-label, Multiple Ascending Dose (MAD) phase (n = 8), where patients were treated with SBE once daily or twice daily over five days. Reporting is according to CONSORT guidelines. Results: SBE was safe and well-tolerated in chronic leg wound patients. There were no significant differences in pain during and after treatment with SBE or the placebo. The SBE treatment reduced bioburden in wounds compared to baseline, with 98% and 49% median reduction after SBE or placebo treatment, respectively. A dose-dependent trend in absolute wound size reduction was observed in the MAD groups with a median (min, max) change of -2.99 (-14.25, -1.5) cm2 in the once-daily and -10.48 (-17.95, -0.38) cm2 in the twice-daily group, respectively. Innovation and Conclusion: This study demonstrated the safe use of HOCl-based SBE in chronic leg wounds with promising trends of immediate antimicrobial action and beneficial effect on wound healing.

The biofilm eradication activity of acetic acid in the management of periprosthetic joint infection

Objectives

Periprosthetic joint infection following joint arthroplasty surgery is one of the most feared complications. The key to successful revision surgery for periprosthetic joint infections, regardless of treatment strategy, is a thorough deep debridement. In an attempt to limit antimicrobial and disinfectant use, there has been increasing interest in the use of acetic acid as an adjunct to debridement in the management of periprosthetic joint infections. However, its effectiveness in the eradication of established biofilms following clinically relevant treatment times has not been established. Using an in vitro biofilm model, this study aimed to establish the minimum biofilm eradication concentration (MBEC) of acetic acid following a clinically relevant treatment time.

Materials and Methods

Using a methicillin-sensitive Staphylococcus aureus (MSSA) reference strain and the dissolvable bead assay, biofilms were challenged by 0% to 20% acetic acid (pH 4.7) for ten minutes, 20 minutes, 180 minutes, and 24 hours.

Results

The MBEC of acetic acid was found to be: 15%, 11%, 3.2%, and 0.8% following a ten-minute, 20-minute, 180-minute, and 24-hour treatment, respectively.

Conclusion

This study found that the MBEC of acetic acid following a 10- or 20-minute treatment time exceeded its safety threshold, making these concentrations unsuitable as a topical debridement adjunct. However, a clinically acceptable concentration (5%) was still found to eliminate 96.1% of biofilm-associated MSSA following a 20-minute treatment time.

Cite this article: S. T. J. Tsang, P. J. Gwynne, M. P. Gallagher, A. H. R. W. Simpson. The biofilm eradication activity of acetic acid in the management of periprosthetic joint infection. Bone Joint Res 2018;7:517–523. DOI: 10.1302/2046-3758.78.BJR-2018-0045.R1

Antibiofilm Properties of Acetic Acid

Bacterial biofilms are known to be extremely tolerant toward antibiotics and other antimicrobial agents. These biofilms cause the persistence of chronic infections. Since antibiotics rarely resolve these infections, the only effective treatment of chronic infections is surgical removal of the infected implant, tissue, or organ and thereby the biofilm. Acetic acid is known for its antimicrobial effect on bacteria in general, but has never been thoroughly tested for its efficacy against bacterial biofilms. In this article, we describe complete eradication of both Gram-positive and Gram-negative biofilms using acetic acid both as a liquid and as a dry salt. In addition, we present our clinical experience of acetic acid treatment of chronic wounds. In conclusion, we here present the first comprehensive in vitro and in vivo testing of acetic acid against bacterial biofilms.