Can Topical Sucralfate Treat Cutaneous Bacterial Infection?

Overuse of systemic antimicrobial drugs has led to documented drug resistance in several common veterinary pathogens, including Pseudomonas aeruginosa. In response, many veterinarians are turning to alternative therapies to treat bacterial dermatoses. While some topical treatments, such as chlorhexidine and silver sulfadiazine, are already commonly used in veterinary medicine, other options are still experimental.

Sulcralfate, the aluminum salt of sucrose octasulfate, is used most commonly to prevent and treat gastric and duodenal ulcers. However, human studies have shown that the ingredient’s therapeutic effects, including wound barrier formation, tissue repair, and antimicrobial properties, may aid in the treatment of cutaneous pathogens. A topical skin cream (Cicalfate, Avene) is available commercially for human use and contains 1% sucralfate, as well as zinc, copper, and magnesium compounds. Veterinary researchers recently performed an in vitro study to test both Cicalfate and its active ingredient, sucralfate, against several common cutaneous bacterial pathogens.

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Study Design

A sulcralfate solution was created using tablets dissolved in sterile saline, and a Cicalfate solution was prepared in dimethyl sulfoxide (DMSO). Several concentrations of each solution were tested, and DMSO was also tested alone to rule out its possible antimicrobial effects.

Tested sucralfate concentrations were as follows:

• 0.002 to 1.0 mg/mL in the Cicalfate solution
• 0.2 to 200 mg/mL in the sucralfate solution

Cutaneous bacterial isolates were inoculated into each of the test solutions, then serially diluted and incubated at 35ºC to 37ºC to observe for growth. Tested bacteria included clinical strains of P aeruginosa, Staphylococcus pseudintermedius, Escherichia coli, and Proteus mirabilis, and American Type Culture Collection (ATCC) strains of P aeruginosa, S aureus, E coli, and Enterococcus faecalis.

The investigators defined minimum inhibitory concentrations (MICs) for the sucralfate and Cicalfate solutions as “the lowest concentration of test solution that inhibited macroscopic growth” of bacteria.

Results

Sucralfate concentrations as low as 25 to 50 mg/mL inhibited macroscopic growth for 5 of the 8 tested cutaneous bacteria: P mirabilis, S pseudintermedius, both strains of E coli, and the ATCC P aeruginosa strain. In addition to those 5 strains, Cicalfate solutions containing as little as 0.06 to 0.25 mg/mL sucralfate also inhibited macroscopic growth of the ATCC S aureus and E faecalis strains. When tested alone, DMSO at strengths of 1% to 18% did not inhibit bacterial growth.

Interestingly, lower concentrations of sucralfate in the Cicalfate product were just as effective as higher concentrations of sucralfate alone, suggesting that the commercial product’s other ingredients, including zinc, copper, and magnesium, offered additional antimicrobial support.

Take-home Message

This study’s results suggest that sucralfate and Cicalfate cream both inhibit growth of several (but not all) of the examined common cutaneous pathogens encountered in veterinary medicine. In particular, the clinical strain of P aeruginosa did not respond to either of the tested solutions. Still, the authors believe that sucralfate offers “an attractive option for topical therapy” of dermatologic bacteria, given the product’s low risks of toxicity and adverse effects.

Dr. Stilwell received her DVM from Auburn University, followed by a MS in fisheries and aquatic sciences and a PhD in veterinary medical sciences from the University of Florida. She provides freelance medical writing and aquatic veterinary consulting services through her business, Seastar Communications and Consulting.