Abstract
Onychomycosis is a very common condition that accounts for 50% of all nail pathologies. Currently 2–5% of the
world population suffers from this disorder. It is primarily caused by dermatophytes, but the infection can also be
caused by yeasts and non-dermatophyte moulds. Onychomycosis is a therapeutic challenge and recently there has
been an increase in resistance to oral and topical antifungal agents, leading to 20–25% relapse and/or reinfection
rate. During the past 5 years, the emergence of laser therapy has been the topic of discussion as a newer, safer
modality of treatment.
Nail clippings and scrapings are the most common methods of sampling for suspected onychomycosis. The
simplest method for detecting fungi is by way of 20% potassium hydroxide (KOH) preparations, but lately show
insufficient sensitivity in onychomycosis – as much as 40–68%. Fungi can also be grown in culture form; however a
70% sensitivity detection failure rate is seen. Recently, histological fungal detection – in the form of Periodic Acid-
Schiff (PAS) stain – has shown high sensitivity at 92% in the detection of fungal elements.
The exact mechanism of action of laser is unknown but it is believed that heat disintegrates fungal structures.
One of the most appealing characteristics of laser therapy is its ability to deliver energy to the target tissue and avoid
systemic side effects at the same time. In 2009 the United Kingdom (UK) Podiatry magazine Podiatry Now published
a letter suggesting laser treatment was “possibly the most radical development in the treatment of onychomycosis
our profession has ever seen”, although concerns were raised over the unproven efficacy and investment costs
involved.
Papers have been published investigating the efficacy of lasers for the treatment of onychomycosis. Even though
laser therapy provides an alternative option with rapid procedure duration, conflicting evidence is shown in a variety
of papers and studies with longer follow-up periods suggest onychomycosis relapse in those treated with laser,
which warrants further investigation.