How to Diagnose Toenail Fungus

How to Diagnose Toenail Fungus | Common Signs and Symptoms

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Several changes in toenails or fingernails may cause people to come to the conclusion that they have developed a fungal nail infection, medically known as tinea unguium or onychomycosis.

This infection commonly starts at the edge of the nail and spreads to the middle, making it brownish or yellowish, brittle and thick.

In severe cases, the nail may also lift off from the nail bed.

People who frequently go to swimming pools, saunas, and communal showers are more susceptible to toenail fungus.

Most people who are infected do not detect it right away until the condition becomes severe. Fungal nail infection is not considered to be a serious health problem unless another medical issue is present.

But, how do you know if you have toenail fungus?

Signs and Symptoms of Toenail Fungus

One of the early signs of fungal infection is a small white patch or powdery substance on your affected toenail.

These are usually mistaken for a scrape or scratch, but if you do not recall hitting your toenail, this could be a fungal infection.

black spot under or on the toenail may also be visible and can be mistaken for dried blood. This dark color is caused by dirt or debris building up under the toenail.

Another early sign of toenail fungus is ridges or lines that appear on the infected nail. These are common and are often overlooked.

You may have toenail fungus if your toenail is distorted in shapebrittle, ragged or crumblydull, and thickened.

These symptoms may be aggravated by improper trimming of the toenails, certain activities, ill-fitting footwear, and lifestyle.

If the condition is left long enough to exacerbate, it will start becoming painful and may lead to a dead toenail.

Wearing shoes will be excruciating, and the infection may produce a foul odor.

Different Manifestations of Fungal Nail Infection

Many types of fungi infect toenails and fingernails. The most common is called Trichophyton rubrum and it may infect the skin (dermatophyte). Nail fungal infection may manifest in these specific ways (1):

How Doctors Diagnose Toenail Fungus

Your doctor will first examine your toenails, but physical exam alone may be unreliable when it comes to diagnosing toenail fungus.

Some conditions, such as psoriasis, hematoma (blood under the nail), and paronychia (skin infection), can mimic the symptoms of a fungal nail infection.

Because there are numerous conditions that can deform nails, even doctors may have a difficult time.

Therefore, your doctor may take a nail sample by scraping debris under your toenail, clipping or drilling a hole in the nail and send it for laboratory testing.

This will identify the type of fungus present in the area and knowing the exact cause will help in determining the best treatment (2).

  • Distal subungual onychomycosis: It starts at the corner of the toenails is the most common type of fungal nail infection in both children and adults. This type is more common in toes than fingernails. Risk factors include athlete’s foot, diabetes, psoriasis, swimming, suppressed immune system, older age, and living with someone who has a fungal infection.
  • Proximal subungual onychomycosis: It starts at the base of the toenail and usually occurs in individuals with a compromised immune system. The common cause of this condition is T. rubrum and non-dermatophyte molds.
  • White superficial onychomycosis: Caused by a fungus called Tricophyton mentagrophytes, this condition is most common in tropical environments.
  • Yeast onychomycosis: Caused by Candida, it is more common in fingernails than in toenails. This condition results in yellow, white, brown, or thickened nails. Individuals who have this condition may also have a yeast infection in their mouths.

Treatments for Fungal Nail Infection

Here are the common treatments to get rid of fungal nail infection.

  1. OTC topical medications: For mild cases of toenail fungus, you can take care of it with over-the-counter topical medications. These antifungal creams, gels, and lotions require a daily application as the fungus is protected by the nail. It may take several months to one year to completely clear the infection. These medications may work more efficiently if you thin your toenail with an over-the-counter lotion that contains urea. This allows the medication to get through the nail’s hard surface. Many people with toenail fungus have had success with Vicks VapoRub. You can use this by applying a small amount of it daily.
  2. Antifungal nail polish: Your doctor may also prescribe circlopirox and you can paint it on the affected nails including the surrounding skin. One of the advantages of topical medications is the minimal risk for side effects.
  3. Oral antifungal therapy: This is considered to be the best treatment for toenail fungus as they work about 50 to 70 percent of the time. Depending on the severity of the infection, these drugs are typically taken for 6 to 12 weeks to get rid of toenail fungus completely. Success seems to improve when oral therapy is combined with topical medications. The disadvantage of oral antifungal drugs is they may cause side effects, such as skin rashes and liver damage. Doctors may not prescribe them for people who are taking certain medications, congestive heart failure, or those with liver problems. Other side effects include headaches, loss of taste, itching, and diarrhea (3).
  4. Nail removal: For severe nail infections, your doctor may suggest removing the affected nail. A new nail will slowly grow back and may take a year to completely replace the old one. This surgery may be combined with antifungal nail polish to treat the nail bed.

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