Understanding Your Results

Positive: fungal DNA detected

A positive result means our qPCR test found DNA from fungi that are associated with nail infections in the nail clipping you sent. Where possible, your report may also indicate the general type of fungus detected (for example, a dermatophyte, the group of fungi most commonly behind toenail infections).

What a positive result does not tell you on its own:

• That fungus is the only cause of your nail changes. A nail can have a fungal infection and another condition at the same time, such as psoriasis or damage from an old injury.
• How severe the infection is or how many nails are affected. We test the sample you send.
• Which treatment is right for you. That depends on your health, your medications, how many nails are involved and other factors a healthcare provider will consider.

Your report is reviewed by a licensed Canadian podiatrist with over 50 years of experience, before it is emailed to you. It's designed to give you and your healthcare provider useful information. It is not a diagnosis on its own and is not a substitute for a healthcare provider.

Negative: fungal DNA not detected

A negative result means no fungal DNA was detected in the sample we received. There are two broad explanations:

1. Your nail changes may have another cause

Thick, discoloured, ridged or lifting nails are not always fungal. Other common causes include:

• Trauma: a stubbed toe, a dropped object, or repeated pressure from tight shoes, running or sports.
• Psoriasis: nail psoriasis can cause pitting, discolouration, crumbling and lifting that look a lot like fungus.
• Lichen planus: an inflammatory condition that can affect the nails as well as the skin and mouth.
• Bacterial infection: some bacteria can discolour a nail, often with a green or black tint.
• Other conditions: nail changes can also be linked to ageing, other skin conditions or general health issues.

2. A false negative is possible

qPCR is a sensitive method, but no test is 100% accurate. The most common reason for a false negative is that the clipping didn't contain enough affected nail, for example if it was taken from the healthy tip rather than the discoloured or thickened part, or if the sample was very small.

If your nail still looks abnormal, is getting worse, or you're simply unsure, talk to a healthcare provider. They may examine the nail in person and suggest further testing. You may also choose to retest with a carefully collected sample.

Inconclusive or insufficient sample

Occasionally a sample can't be tested reliably. Common reasons include a sample that is too small, contaminated, unlabelled, or missing an order number.

If your sample can't be tested for reasons within our control, we'll send you a replacement kit free of charge, as set out in our Terms of Service. Email support@fungalnailtest.com with your order number if you have questions.

Tips for a good sample next time:

• Remove any nail polish, then wash and dry your foot or hand.
• Wipe the nail and clipper with the alcohol swab.
• Clip from the most affected part of the nail and include as much discoloured or thickened nail as you comfortably can, plus any crumbly material from under the edge.
• Seal everything in the pouch and write your order number on the form.

Next steps: who to talk to

Whatever your result, bring your report to a healthcare provider if you'd like advice or treatment. Good places to start:

• A pharmacist can talk you through non-prescription options and help you decide whether you need to see someone else. In many provinces, pharmacists can also assess and prescribe for some minor conditions.
• Your family doctor or nurse practitioner can examine the nail, consider your overall health and medications, and prescribe treatment or refer you.
• A podiatrist or chiropodist specializes in foot and nail care and can assess, trim and thin affected nails and advise on treatment.

A general overview of treatment

This section is general information only. Your healthcare provider will recommend what's appropriate for you. Common approaches for fungal nail infections include:

• Topical antifungals: medicated solutions or lacquers applied to the nail. Some are available without a prescription and others need one. They usually need to be applied regularly for many months.
• Oral prescription antifungals: tablets prescribed by a doctor or nurse practitioner. They aren't suitable for everyone, can interact with other medications, and sometimes require blood tests to check liver function.
• Nail care procedures: a foot-care professional may trim or thin (debride) thickened nails, which can make other treatments more effective and nails more comfortable. In some cases, part or all of a nail may be removed.
• Laser and light-based treatments: offered by some clinics. Research is ongoing, and the American Academy of Dermatology notes that in the United States lasers are approved to improve a nail's appearance rather than to treat the infection itself. These treatments are usually not covered by insurance.

Treatment takes time. Toenails grow slowly, so even when treatment works, the damaged part of the nail has to grow out. You may see healthy, clear nail starting to grow from the base before the rest of the nail looks normal, and it can take a year or longer for a toenail to grow out completely. Fungal nail infections can also come back, so prevention matters: keep feet clean and dry, change socks daily, wear sandals in public showers, and don't share nail clippers or towels.

When to retest

• Negative result, but your nail still looks wrong: talk to a healthcare provider. A retest with a well-collected sample (taken from the most affected area) may help.
• Inconclusive result: follow the instructions on your replacement kit carefully.
• After treatment: ask your healthcare provider about timing. Because qPCR detects DNA, it may pick up DNA from fungi that are no longer active, so testing very soon after treatment may not reflect whether treatment worked. The appearance of the nail also lags behind, because damaged nail takes months to grow out.
• New changes in a different nail, or changes that return after a nail had cleared, may be worth checking again.

Sources and further reading

• NHS: Fungal nail infection
• American Academy of Dermatology: Nail fungus diagnosis and treatment
• Canadian Dermatology Association: Nail fungus and infection
• Mayo Clinic: Nail fungus, diagnosis and treatment

This page is general information and is not a substitute for a healthcare provider.