The cure for problem nails: a whiff of rotten eggs…

The source for their therapy is hydrogen sulphide, the naturally occurring volcanic gas capable, they say, of fighting a wide range of nail pathogens, including those that have thwarted some of the commonest antifungal treatments.

Dr Albert Bolhuis of Bath’s department of life sciences said: “Thanks to its ability to efficiently reach the site of infection and its novel mode of action, we believe that a topically applied medicine containing hydrogen sulphide could become a highly effective new treatment for nail infections, which avoids the limitations of current therapies.”

Fungal based nail infections are widespread across the world and together with a minority of bacteria-derived infections, could affect up to one in 10 of the global population. Among over-70s the proportion is almost one in two.

Both oral antifungal and manual treatments can take considerable time to work, if at all: two to four months in the case of oral medicines, sometimes years in the case of manual applications. 

But the difficulty of enabling drugs to penetrate through toenails, where microbes are embedded, compromises success while some treatments carry negative side effects, suggest the researchers.

But previous work suggested to the Bath and KCL team that hydrogen sulphide could penetrate the nail plate more efficiently than existing drugs.

In their recent in-vitro laboratory tests, they used a chemical that breaks down to release hydrogen sulphide gas, detailing in Scientific Reports that it disrupted microbial energy production and led to irreversible damage, killing the fungi responsible for the infection.

They also said their work demonstrated strong antimicrobial activity against a wide range of nail pathogens, including fungi resistant to common antifungal treatments. 

Bolhuis said the research laid the foundation for a “compelling alternative” from persistent and drug-resistant fungal nail infections.

The researchers now plan to develop a treatment suitable for patients’ use within the next five years. 

Professor Stuart Jones, Director of the Centre for Pharmaceutical Medicine Research at KCL added: “We are looking forward to translating these findings into an innovative topical product that can treat nail infection.” 

While the toxicity of hydrogen sulphide may be too low to constitute a barrier to use as a product, the scientists acknowledge its infamous odour might be a barrier to use. Work is underway to identify the formulation to limit the likelihood of unpleasant smells.

Pic: Shutterstock (Maria Malia)