Toenail Fungus

Fungus is an opportunistic organism that thrives in moist environment. Toenails are a common area of fungal infection since the feet can provide a good medium for fungal growth due to sweating from use of footwear. As much as 30% of diagnosed fungal infections affect the toenail. Poor foot hygiene can also be a cause of toenail fungal infection. Concomitant illness that weakens the immune system such as diabetes, cancer, or HIV may open the door for fungal infection.

Symptom of Toenail fungus Infection

Infection of the toenail with fungus usually does not produce symptoms; hence, most patients do not seek treatment. Appearance of the nails will be discussed below to give a clue about possible toenail fungal infection. It is pertinent to treat fungal infection in people with diabetes as this could lead to complications.

Types of Toenail Fungal Infection

• Distal nailbed fungal infection

Distal nailbed infection involves the junction of the skin and nail. The infection typically starts at the edge of the nail then extends to the nailbed. The nail turns to yellow over time when not treated immediately. In late stages of the infection, the nail separates from the nailbed due to buildup of fungus underneath. Redness and scaling of the skin and soles of the affected nail is likely to occur. The fungus T. rubrum is the common cause.

• Proximal nailbed fungal infection

This type of fungal infection affects the nailfold and portion of the nail near the cuticle. This is caused by T. rubrum and T. megninii. Proximal nailbed fungal infection may indicate but does not confirm HIV infection.

• White superficial onychomycosis

As the name implies, this condition is manifested as chalky, white spots (the fungus itself) sprinkled over the surface of the nail. Infection typically begins and is confined to the overhanging skin and portion of the nail near the cuticle. Infection of the entire nail may occur with time. T. mentagrophytes and aspergillus are the common causes.

• Candida infection

Candida is a very opportunistic type of fungus that produces massive destruction of the nailbed. It is usually associated with long-term candida infection of the mouth or other body parts.

Diagnosis of Toenail Fungal Infection

Visualization of the nails is not adequate to diagnose toenail infection caused by fungus. Studying infected nailbed scraping under the microscope makes confirmation of diagnosis. Different types of fungus can be observed with the different types of infection mentioned above.

Treatment

• Oral antifungals

Terbinafine and itraconazole are oral medications that are prescribed for 3 to 4 months. Treatment with fluconazole usually lasts for 6 to 12 months. These medications are both effective in treating pediatric and adult fungal infection.

• Nail avulsion

Nail avulsion or unroofing of the nail is reserved for severe cases that do not respond to oral antifungals. Curettage or scraping of infected nailbed tissues is also done. The presence of yellow streaks within the nail called dermatophytoma usually necessitates nail avulsion due to poor response with oral antifungals.

• Topical antifungals

Topical antifungals have historically been ineffective at curing toenail fungus. The entry of ciclopirox and amorolfine in the market has given some success to topical antifungals. Topical and oral antifungals are combined to treat candida toenail infection.  For other types of toenail fungal infection, it is important to note that these medications are only moderately effective when compared to their oral counterparts.

• Proper foot hygiene

Practicing good foot hygiene prevents fungus from replicating in the feet. Drying the feet before wearing of socks and shoes should be done. Avoid walking barefoot in public locker and shower rooms to avoid contracting fungal infection. Sharing footwear or socks is out of the question.