An Article Written By Bonnie McNab
Podiatrist – New Step Podiatry
Whilst not an immediate life-threatening condition, fungal infections are a cause for concern as they can negatively affect an individual’s quality of life due to discomfort, altered cosmetic appearance and can lead to a more serious infection.
What is fungus?
Fungi are living things, separate from animals and plants, that are around us (and on us), at any given time. When podiatrists talk about fungus, it’s likely that they’re talking about fungal infections of the skin (such as tinea pedis) or toenails (onychomycosis). Interestingly, there are a number of dermatophytes, yeasts and molds that can lead to different types of fungal skin and nail infections.
Fungus on the Skin
Fungal infections on the foot can present on the tops and soles of the foot (such as tinea pedis or acute vesicular tinea pedis) or between the toes (interdigital tinea pedis). There are several dermatophytes that can cause a fungal infection, with the most common being Trichophyton Rubrum (tinea pedis). Treatment for fungal skin infections usually consists of practicing good foot hygiene and applying a topical anti-fungal cream.
The presentation of skin fungus varies but symptoms typically involve at least one of the following:
- peeling or very dry looking skin
- itching or soreness
- small pustules or bumps on the skin
- maceration (in-between your toes)
An example of Tinea Pedis
An example of Acute Vesicular Tinea Pedis
Onychomycosis (Fungal Nails)
Fungal nail infections can be caused by a mold, yeast or the same fungi that infect the skin (dermatophytes). Podiatrists categorise fungal nails based on whether they are located on the surface of the nail or whether they extend deeper (underneath the nail).
Superficial infections are often simple to treat as the fungus can be easily filed away and topical anti-fungals can target the infection directly. Deeper (subungual) infections can be trickier to treat for a number of reasons – it is harder for topical anti-fungals to penetrate through the nail plate and into the infected area, and nails are notoriously slow-growing (it can take up to 12 months for a great toenail to grow from base to tip!).
If the infection is superficial or if it is only affecting a small percentage of 1 or 2 nails, topical anti-fungals may be all that is required to treat the infection.
The presentation of fungal nails varies but symptoms usually consist of a yellow/brown discoloration underneath the nail, white spots on top of the toenail and/or lifting of the nail from the nail bed. Additionally, fungal nails may be more likely following a traumatic nail event such as dropping something onto the toe, kicking something and injuring the nail or wearing tight-fitting shoes. Trauma can create a portal of entry for fungus to enter the toenail and cause infection.
The most common fungal nail infections are:
- Distal lateral onychomycosis
- Proximal subungual onychomycosis
- Superficial white onychomycosis
- Candidal onychomycosis
- Total dystrophic onychomycosis
How did I get a fungal infection?
Fungal spores are in our environment at almost any given time and, when given the right conditions, they thrive. Research has indicated that fungal infections become more common as we age and are a particular concern for the elderly and immunocompromised population.
Some factors that can increase your risk of developing a fungal infection include:
- Athlete’s foot
- Poor foot hygiene (i.e. not washing your feet properly or changing socks, hosiery or shoes on a regular basis, particularly if you are quite active and/or prone to sweaty feet)
- Frequent contact with fungi i.e. going barefoot in public spaces such as gyms, swimming pools and saunas
- Damaged nails
- Wearing tight, enclosed shoes
How is fungus diagnosed?
Clinicians, including podiatrists, can often identify a fungal skin or nail infection with a simple physical examination and patient history. However, for accurate diagnosis, diagnostic testing is recommended – especially if systemic medication is to be used.
For fungal skin infections a skin scraping may be performed to firstly diagnose whether it is indeed fungus and then to identify the infecting organism.
The most common way to test for onychomycosis is through nail culturing whereby a clipping/scraping is taken from the affected nail/s and sent to a pathology lab for testing.
What else can be mistaken for fungus?
There are several other nail conditions which can present similarly to onychomycosis, such as:
- lichen planus
- yellow nail syndrome
- idiopathic or traumatic onycholysis (lifting of the nail)
There are a number of other skin conditions which can present similarly to fungal skin infections such as:
How do you Treat fungus?
Fungal infections can be treated topically, orally and, in some cases, using a combination of the two. Onychomycosis, particularly moderate to severe cases, can be difficult to cure and treatment is most successful if it is started early. Oral anti-fungals have higher cure rates and shorter treatment periods than topical treatments, but have potential adverse effects such as liver toxicity and drug interactions.
There are a number of considerations when treating a fungal infection but successful treatment largely depends on a number of factors such as:
- if the fungal infection is affecting your skin, nails or both
- what type of fungus is causing the infection i.e. dermatophyte, yeast or mold
- how extensive the fungal infection is / how long you’ve had the infection
- how you’ve responded to previous treatments
For onychomycotic infections, patients may benefit from seeing a podiatrist on a regular basis during the course of their treatment. Podiatrists can carefully reduce the affected toenail which can reduce the number of spores in the nail and make it easier for the topical anti-fungal to penetrate the nail and treat the infection. Additionally, nail laser therapy may be recommended by your podiatrist as an adjunct during your course of treatment – this has shown success in improving the appearance of the nails.
As with a number of other conditions, prevention is greater than cure. Since fungi thrive in damp surroundings, it’s essential that you keep your feet dry and clean – this can be as simple as changing your socks at least once per day and making sure that you’re not going barefoot into enclosed shoes.
Other things that can help reduce the risk of developing a fungal infection include:
- Drying your feet well (including in between your toes) after they come into contact with water i.e. after showering, swimming or exercise
- Keeping your toenails trimmed and avoiding nail trauma by wearing appropriately fitting enclosed shoes
- Wearing thongs in shared spaces such as pools, gyms and saunas
- Not sharing shoes, socks or towels with other people
- Washing socks, hosiery and bath mats in a 60 degree Celsius wash with an anti-fungal solution such as ‘Canesten Hygiene Laundry Rinse’
The take home Message
Fungi is around us at any given time and the best way to treat a fungal infection is to prevent it (where possible) or treat it in its initial stages.
Simple measures such as keeping your feet clean and dry, changing your shoes and socks regularly, avoiding going barefoot in public spaces and keeping your toenails trimmed can help reduce the chances of contracting a fungal infection.
If you notice any changes in the appearance of your skin and/or nails, it is important to act quickly – seek an appointment with your podiatrist who can recommend the best course of treatment. Delaying treatment or thinking it’s just a cosmetic concern isn’t the best course of action as long term fungal infections can contribute to a secondary bacterial infections including cellulitis, a potentially serious infection.
References used Within this Article Include
- Lipner, S. R., & Scher, R. K. (2018). Part I: Onychomycosis: Clinical Overview and Diagnosis. Journal of the American Academy of Dermatology. doi:10.1016/j.jaad.2018.03.062
- https://dermnetnz.org/topics/tinea-pedis-images – images of tinea pedis foot x3