Acetic acid treatment of pseudomonal postoperative wound infection

Efficacy and optimal dose of acetic acid to treat colonised burns wounds: protocol for a pilot randomised controlled trial

INTRODUCTION

Despite of recent advancement in the burns wound management, burn wound infection (BWI) is still one of the major cause of burns mortality. Patients who survive their burns injury still suffers from BWI related complication like delayed wound healing and poor scarring. BWI has been treated by application of topical antimicrobial agents or systemic antibiotics. Due to the global risk of developing systemic antibiotics resistance, medical research focuses on identifying single topical agent which has effective antimicrobial activity, easily available and cost effective. One such agent is acetic acid (AA). AA has been used as a topical antibacterial agent for the treatment of burns wounds for many years and has shown to have activity against gram-negative organisms including Pseudomonas aeruginosa. So far there has been no consensus on optimal concentration that has effective antimicrobial activity, frequency of application, duration of treatment and most importantly good patient's tolerability. A randomised control study is required to answer all these questions.

OBJECTIVE

To investigate the efficacy and tolerability of 0.5% and 2% of AA when applied to colonised burns wounds for 3 days after admittance to the Queen Elizabeth Hospital Birmingham.

METHODS AND ANALYSIS

This is a double-blinded, prospective, randomised, controlled, single-centre trial. Patients will be screened for eligibility in the inpatient area and those who are found to be eligible will be randomly assigned to one of two treatment groups: group 1: 0.5% AA (10 patients); group 2: 2% AA (10 patients); total number: 20 patients.

OUTCOME MEASURES

Primary outcome: Efficacy will be assessed by measuring the bacterial load from microbiology wound swabs for three consecutive days.Secondary outcomes: (1) The assessment of antimicrobial activity of AA and the minimum inhibitory concentrations. (2) Patient's tolerance by assessing Visual Analogue Scale pain score. (3) Time to 95% wound healing of treatment area. (4) Patient's perceived treatment allocation.

ETHICS AND DISSEMINATION

AceticA trial protocol was approved by the National Research Ethics Service (West Midlands-Edgbaston Research Ethics Committee; 17/WM/0407; IRAS 234132). This article refers to protocol version 5.0 dated 6 July 2020. The analysed results will be presented at national and international conferences related to management of burn patients. The generated articles based on the trial results will be submitted to peer review journals for publication.

TRIAL REGISTRATION NUMBER

ISRCTN11636684.

Evaluation of the antibacterial, antibiofilm, and anti-virulence effects of acetic acid and the related mechanisms on colistin-resistant Pseudomonas aeruginosa

BACKGROUND

Pseudomonas aeruginosa (P. aeruginosa) has been majorly implicated in the infection of burns, wounds, skin, and respiratory tract. Colistin is considered the last line of defense against P. aeruginosa infections. However, colistin is becoming increasingly invalid in treating patients infected with colistin-resistant (COL-R) P. aeruginosa. As one of the disinfectants used for wound infections, acetic acid (AA) offers good antibacterial and antibiofilm activities against P. aeruginosa. This study investigated the effects of AA on COL-R P. aeruginosa in terms of its antibacterial, antibiofilm, and anti-virulence properties and the corresponding underlying mechanisms.

RESULTS

The antimicrobial susceptibility and growth curve data revealed that 0.078% (v/v) AA exhibited good antibacterial activity against COL-R P. aeruginosa. Subinhibitory concentrations of AA were ineffective in inhibiting biofilm formation, but 4 × and 8 × of the minimum inhibitory concentration (MIC) was effective in removing the preformed biofilms in biofilm-eradication assays. The virulence results illustrated that AA inhibited COL-R P. aeruginosa swimming, swarming, twitching, and pyocyanin and elastase production. The analysis of the potential antibacterial mechanisms of AA on COL-R P. aeruginosa revealed that AA acted by increasing the outer and inner membrane permeability, polarizing the membrane potential, and decreasing the reduction potential in a concentration-dependent manner. The qRT-PCR results revealed that AA may inhibit the virulence of COL-R P. aeruginosa by inhibiting the expression of T3SS-related and QS-related genes.

CONCLUSIONS

AA possesses antibacterial, antibiofilm, and anti-virulence properties that ultimately lead to the alteration of the bacterial membrane permeability, membrane potential, and reduction potential. Our findings indicated that AA is presently one of the effective treatment options for infections. A high concentration of AA (> 0.156% v/v) can be used to sterilize biofilm-prone surgical instruments, for hospital disinfection, and for treating the external wound, whereas a low concentration of AA (0.00975-0.039% v/v) may be used as an anti-virulence agent for adjuvant treatment of COL-R P. aeruginosa, thereby further improving the application value of AA in the treatment of infections.

Role of an acidic environment in the treatment of diabetic foot infections: A review

Management of diabetic foot ulcers is the biggest challenge to the clinician, as conventional antibiotic therapies and local wound care have their own limitations. They are not effective for control of infections and promotion of healing because of cytotoxic effects. In view of cytotoxicity of routinely used topical antiseptic agents, this article focuses on the search of an ideal topical antiseptic agent that is safe and effective in controlling infectious agents and also in promoting the healing process. This review focuses on the use of various acids such as citric, acetic, hyaluronic, and hypochlorous acids as topical agents in diabetic foot infections. This article also focuses on the different roles of acids in the treatment of diabetic foot infections.

Synergistic Impacts of Organic Acids and pH on Growth of Pseudomonas aeruginosa: A Comparison of Parametric and Bayesian Non-parametric Methods to Model Growth

Different weak organic acids have significant potential as topical treatments for wounds infected by opportunistic pathogens that are recalcitrant to standard treatments. These acids have long been used as bacteriostatic compounds in the food industry, and in some cases are already being used in the clinic. The effects of different organic acids vary with pH, concentration, and the specific organic acid used, but no studies to date on any opportunistic pathogens have examined the detailed interactions between these key variables in a controlled and systematic way. We have therefore comprehensively evaluated the effects of several different weak organic acids on growth of the opportunistic pathogen Pseudomonas aeruginosa. We used a semi-automated plate reader to generate growth profiles for two different strains (model laboratory strain PAO1 and clinical isolate PA1054 from a hospital burns unit) in a range of organic acids at different concentrations and pH, with a high level of replication for a total of 162,960 data points. We then compared two different modeling approaches for the interpretation of this time-resolved dataset: parametric logistic regression (with or without a component to include lag phase) vs. non-parametric Gaussian process (GP) regression. Because GP makes no prior assumptions about the nature of the growth, this method proved to be superior in cases where growth did not follow a standard sigmoid functional form, as is common when bacteria grow under stress. Acetic, propionic and butyric acids were all more detrimental to growth than the other acids tested, and although PA1054 grew better than PAO1 under non-stress conditions, this difference largely disappeared as the levels of stress increased. As expected from knowledge of how organic acids behave, their effect was significantly enhanced in combination with low pH, with this interaction being greatest in the case of propionic acid. Our approach lends itself to the characterization of combinatorial interactions between stressors, especially in cases where their impacts on growth render logistic growth models unsuitable.

The large scale antibacterial, antifungal and anti-phage efficiency of Petamcin-A: new multicomponent preparation for skin diseases treatment

BACKGROUND

Human and animal skin diseases of bacterial, fungal and viral nature and their complications are widespread and globally cause a serious trouble. Their prevalence is increasing mainly due to drug resistance. Consequently, demand has increased for new effective antimicrobial drugs, which also should be less toxic, possess a wider spectrum of action and be economically more beneficial. The goal was to investigate antibacterial, antifungal and anti-phage activity of Petamcin-A-a new multicomponent preparation. It contains acetic acid and hexamethylenetetramine as main active antimicrobial components, as well as phosphatidylcholine, tocopheryl acetate and glycerol as excipients.

METHODS

Bacteriostatic activity and minimal inhibitory concentrations of the preparation against various test-organisms were determined by agar well diffusion assay. Antifungal activity was tested by agar dilution assay. To explore anti-phage activity double agar overlay plaque assay was used. Nystatin, chlorhexidine and acetic acid were used as control agents for comparative analysis. Statistical analysis was done with GraphPad Prism 5.03 or R 3.1.0 software.

RESULTS

The results showed a higher activity of Petamcin-A against all bacterial and fungal test strains compared with its components or control agents. The preparation was more effective against tested gram-positive bacteria than gram-negative ones. Petamcin-A expressed bactericidal activity against almost all test strains. In addition, the preparation demonstrated high activity against T4 phage of Escherichia coli C-T4 completely inhibiting its growth. 5-fold diluted Petamcin-A also exhibited considerable activity reducing phage concentration by 2.6 Log10.

CONCLUSIONS

Petamcin-A has a high antimicrobial activity against all tested strains of bacteria, yeasts and moulds. The preparation also exhibited high anti-phage activity. Moreover, taking into account that Petamcin-A has no observable toxicity on skin and its components are not expensive, it can be advantageous for management of various skin medical conditions.

Acetic acid treatment of pseudomonal wound infections--a review

PURPOSE

Pseudomonas aeruginosa is a significant cause of burn wound infections and, skin and soft tissue infections. The antiseptic management is an integral part of the management of wound infections and is essential to control wound infection. Although commonly used, concerns have been raised.

RESULTS

Available experimental data suggest that many commonly used antiseptic agents may be toxic to the cells involved in wound healing process and may affect the process of normal tissue repair. In view of this, the present review summarized the various organic acids commonly used as a substitute for antiseptics to control pseudomonal wound infections with special reference to acetic acid and their role in the process of wound healing.

CONCLUSION

Acetic acid is to be kept in mind as one of the alternatives when infection is caused by multiple antibiotic resistant strains of P. aeruginosa. At a time when bacterial resistance to antibiotics is a matter of increasing concern, the value of topical agents such as acetic acid should not be forgotten.

Simple and effective approach for the treatment of traumatic wounds in non-diabetic patients: a prospective open study

Infection is one of the most important obstacles in the wound-healing process. Conventional methods used for the treatment of wound infections have their own limitations and hence, are difficult to control. If infection is not addressed well in time, it will further increase morbidity and cost of treatment. An attempt was made to develop a simple and effective treatment modality by using citric acid as the sole antimicrobial agent to control bacterial infections of traumatic wounds. A total of 259 cases of traumatic wounds infected with a variety of bacteria were investigated for culture and susceptibility, and susceptibility to citric acid. Citric acid ointment (3%) was applied to traumatic wounds to determine its efficacy in their treatment of traumatic wounds. In a culture and susceptibility study, a total of 369 aerobic bacteria and 7 fungi were isolated, with Staphylococcus aureus (30.31%) being the most common isolate and ciprofloxacin (61.43%) being the most effective agent. All the isolates were found to be inhibited by citric acid in in vitro studies (minimum inhibitory concentration--500-2500 µg/ml). Citric acid ointment was found effective in controlling infections. Out of 259 cases, 244 (around 95%) were healed completely in 5-25 applications of 3% citric acid. As citric acid has antibacterial activity and wound-healing property; hence it is the best alternative for the treatment of traumatic wounds. Besides these properties, citric acid has no adverse effects and it is a good dressing agent.

A simple and effective approach for the treatment of chronic wound infections caused by multiple antibiotic resistant Escherichia coli

Antimicrobial resistance is a major problem in present-day therapy. Despite the advent of newer antimicrobial agents with a broad spectrum of activity, multiple antibiotic resistant pathogens are difficult to eliminate from infected sites. The present study was carried out to develop an approach, using citric acid as a sole antimicrobial agent, for the treatment of chronic wound infections caused by multiresistant Escherichia coli (MAREC). A total of 34 cases of chronic wound infections yielding MAREC isolates on culture were studied. The antibacterial effect of citric acid against MAREC was evaluated in vitro by broth dilution method. Three percent citric acid gel was applied to each wound once daily until it healed completely. All 34 isolates were inhibited by citric acid with minimum inhibitory concentrations in the range of 1500-2000 microg/ml. Topical application of 3% citric acid to wounds 7-42 times resulted in elimination of MAREC from infected sites and successful healing of wounds in all 34 patients. This treatment modality was simple, reliable, non-toxic and effective. Hence, the use of citric acid for the cost-effective treatment of wound infections caused by MAREC is recommended.

Management of bioburden with a burn gel that targets nociceptors

AIM

To assess the effectiveness of RescuDerm, an amorphous, water-soluble burn gel in controlling Pseudomonas aeruginosa growth in rat full-thickness wounds contaminated with 10(3), 10(5) or 10(7) CFU/g tissue.

METHOD

Wounds were treated daily for 72 hours with a placebo gel, a 5% w/w mafenide acetate gel (MAF), or with four modalities of RescuDerm application.

RESULTS

All RescuDerm treatments were equally effective within 24 hours in preventing further Pseudomonas aeruginosa growth in wounds contaminated with 10(3) CFU/g tissue. Pseudomonas aeruginosa levels remained at or below this baseline count for 72 hours in all but one of the RescuDerm treatments. The bioburdens in MAF-treated wounds were negligible, averaging 0.14 +/- 0.09 log10 CFU/g tissue. While RescuDerm and MAF remained bacteriostatic in wounds contaminated with 10(5) CFU/g tissue, this property disappeared at higher bioburdens.

CONCLUSION

RescuDerm can be used for the management of cutaneous injuries sustained in environments deemed marginally or moderately contaminated. Heavily contaminated wounds would require irrigation prior to application to reduce their bioburden below 10(5) CFU/g tissue.

In vitro bactericidal efficacy of a new sun- and heat burn gel

We assessed the in vitro bactericidal efficacy of a new sunburn gel (Rescudermtrade mark; RESC) against planktonic and sessile Pseudomonas aeruginosa (PSEUD) and Staphylococcus epidermidis (STAPH). While PSEUD levels were 4log(10) lower than those of STAPH within 24h of adding RESC to contaminated nutrient broths, all bacterial counts were comparable by 48h. PSEUD and STAPH levels were then measured after applying either a single or three consecutive aliquots of RESC to polyurethane sponges. Gel was removed after 5 or 20min, or left on for 72h. Bacterial counts in placebo-treated sponges had plateaued by 24h to values above 9log(10)CFU/mL. In contrast, six out of seven of the RESC application modalities reduced bacterial levels below 4log(10)CFU/mL for 72h. RESC remained effective against STAPH despite up to a 24h treatment delay, irrespective of the number of applications. Repeated RESC applications were required to maintain PSEUD below 4log(10)CFU/mL when the delay exceeded 7h. These data demonstrate the differential susceptibility of planktonic and sessile bacteria to RescuDermtrade mark. This product might be a good candidate for reducing the opportunity for wound infection, especially in burns.

Citric acid treatment of severe electric burns complicated by multiple antibiotic resistant Pseudomonas aeruginosa

A case of severe electric burns complicated by multiple antibiotic resistant Pseudomonas aeruginosa not responding to various antibiotics administered systemically is presented. Citric acid (3%) was used successfully to eliminate Pseudomonas aeruginosa from burn wounds and infection was completely controlled in 14 days. Citric acid treatment is evidently of value in the clinical control of burn wound colonization caused by difficult strains of Pseudomonas aeruginosa.