Topical probiotics in the treatment of infected wounds in critical care

Difficult-to-heal and/or infected wounds are frequently encountered in patients in intensive care units. Studies in recent years have proposed the use of topical probiotics to treat wound infections due to their ability to reduce inflammation, lower pH, and release antimicrobial compounds.¹

The 2019 study by Stanbro et al.¹ investigated the impact of lactobacilli (Lactobacillus acidophilus, Lactobacillus casei and Lactobacillus reuteri) on infected wounds. There were no adverse effects. The results showed that the topical application of Lactobacillus was effective against gram-negative multidrug-resistant (MDR) wound pathogens such as A. baumannii.

The 2019 article by Venosi et al.² presents the case of an 83-year-old woman with critical limb ischaemia and a difficult-to-treat, infected ulcer on her right leg. This patient received complementary treatment in intensive care with local application of probiotic bacteria. During the treatment, progressive healing of the lesion with microbiological resolution of the polymicrobial wound infection was observed. The results seem to confirm the usefulness of complementary probiotic therapy in difficult-to-treat infected wounds.

The 2020 study by Coman et al.³ evaluated the probiotic efficacy of SynBio (1:1 combination of Lactobacillus rhamnosus and Lactobacillus paracasei) in counteracting chronic ulcer infections. The results showed that topical probiotics have a good antimicrobial capacity and adhesion percentage to HaCaT cells and fibroblasts was 19% and 17%, respectively, which highlights the possibility of creating a protective environment that prevents pathogens by forming biofilms to counter infections. Therefore, topical probiotics could be used successfully to complement conventional therapies in the treatment of chronic ulcers due to their ability to eliminate pathogenic microorganisms and improve ulcer healing.

The 2019 study by Lenzmeier et al.⁴ found that patients with severe burns are susceptible to bacterial infection, which often results in sepsis, organ failure and death. The pathogen Pseudomonas aeruginosa (P. aeruginosa), an organism that is inherently resistant to multiple antibiotics, is a common cause of sepsis in critical patients. Therefore, it is essential to develop a topical treatment unrelated to conventional antibiotics for the prevention of P. aeruginosa infection. This study examines the effectiveness of a concentrated supernatant from Lactobacillus gasseri in inhibiting P. aeruginosa biofilms and reducing wound bioburden and sepsis. The results showed that probiotics inhibited P. aeruginosa growth, prevented biofilm development, and eliminated partially developed biofilms, reduced mortality and prevented systemic spread. Their results suggest the potential of topical probiotics in preventing sepsis from infection in critical burns patients and immunocompromised patients.

The 2016 study by Argenta et al.⁵ analysed the efficacy of probiotics (Lactobacillus plantarum) in severe burns. The results showed that probiotics inhibited septicaemic accumulation of the pathogen in remote organs. In addition, probiotic therapy successfully suppressed infection-dependent induction of TNF-α and interleukins 6 and 10 in the liver. Topical probiotics show great potential as complementary treatment of complicated burns.

The potential of topical probiotics on infected wounds in critical patients can be proven through the analysis of the abovementioned recent studies. Moreover, as this treatment accelerates healing, it could reduce the costs of treating infected wounds and increase the quality of life of critical patients.

However, it is worth noting that although the evidence reviewed appears to indicate that we can expect positive results from topical probiotics, the few human studies are not sufficient to establish a general recommendation. More studies are needed to assess the efficacy and possible complications of this treatment in a larger sample of patients, and to analyse its effect in combination with other treatments. Thus, we can offer patients the best care based on the latest evidence.

Funding

The author declares that she has received no funding for this paper.