Can nail fungus be cured?

Author: Sergey Sukhoversha, surgeon, exclusive distributor of MedArt A/S in Ukraine (Ukraine)

Source: KOSMETIK international journal No. 1/2012, pp. 86-88

Onychomycosis is an infectious fungal disease of the fingernails and toenails caused by dermatomycetes, yeast or mold fungi.

As part of the international screening project “Achilles” (1997–1998), 92,500 patients were examined in Ukraine. Fungal infection of the feet was detected in 31% of those examined, of which 52% had onychomycosis. The incidence of onychomycosis increases with age and doubles every 10 years of life. For example, the incidence of onychomycosis in children (under 18 years of age) is 2.6%, while in the elderly it can be 50–90%.

Causes and diagnosis of the disease

Onychomycosis is not a life-threatening disease, but can cause pain, discomfort and cosmetic defects. This reduces the quality of life.

Factors predisposing to the disease are numerous: hereditary predisposition, diabetes mellitus, endocrine pathology, cancer, vascular diseases, obesity, menopause, hyperhidrosis, unbalanced diet, hot humid climate, immunodeficiency, frequent visits to public baths, swimming pools, frequent injury to the nail, wearing tight shoes and etc.

Onychomycosis can affect the nail bed, nail plate, and nail matrix.

The main causative agent is fungi of the dermatophyte family (Trichophyton rubrum, Trichophyton mentagrophytyes) - 90% of all fungal nail diseases. In second place are yeasts of the genus Candida. Candidal onychomycosis is characterized mainly by damage to the fingernails.

By the appearance of changes in the nails, one or another type of fungus can be diagnosed.

Trichophyton rubrum is often multiple lesions of the nails. On the legs it begins with the appearance of yellow spots and longitudinal stripes along the edges of the nail plate, on the hands - with spots in the center of the nail plate.

Trichophyton interdigitale – spots or stripes of bright yellow color appear in the thickness of the nail plate in the center; thickening and deformation with uneven edges are observed at the free edge of the nail.

Candida yeast fungi affect the nail plate from the back or side folds and are located mainly on the hands.

Molds most often develop secondarily, against the background of onychodystrophy. Depending on the type of pathogen, the color of the nail can be yellow, green, blue, brown or black.

Fungal infection of the nail is always secondary. A fungal infection spreads from the affected skin of the hands or feet to the nail. Moreover, infection occurs from the edges of the nail, since the intact nail plate is impenetrable to the fungus. Penetrating under the nail, the fungus spreads along the nail bed and can reach the matrix - the growth zone of the nail.

Depending on the route of infection, onychomycosis is classified as follows (N. Zaias, 1972):

• distal form - the nail is affected from the edges of the nail bed; the nail plate becomes whitish, its shape changes, the nail becomes uneven and crumbles;
• superficial form - whitish spots appear on the surface of the nail, which increase and affect the entire nail plate;
• proximal form - the nail is affected from the nail fold and spreads to the nail matrix;
• total dystrophic form - the nail plate is uneven, thickened, whitish-yellow, with subungual hyperkeratosis.

As you know, the correct diagnosis determines 90% of the success of treating the disease. Onychomycosis should be differentiated from nail changes associated with psoriasis, lichen planus, eczema, onychodystrophy, and Reiter's disease.

To confirm the diagnosis of onychomycosis, microscopic and cultural studies are used. The most reliable method is the PCR method, the accuracy of which is 94%. Laboratory diagnosis is important, since changes in the appearance of the nail can be observed in other diseases of non-infectious origin.

Features of treatment

Treatment of onychomycosis is still a significant problem in dermatology. The reason for this is the anatomical feature of the nail plate. The localization of the fungus under the nail plate makes it difficult for fungicidal agents to reach the lesion, which creates enormous difficulties in the treatment of onychomycosis. External and systemic treatment methods are used. The application of local fungicidal agents makes it possible to create high concentrations of the active substance without systemic side effects, but, unfortunately, local drugs do not penetrate the nail plate well and cannot be a radical method of treating onychomycosis. If the matrix of the nail plate is damaged, treatment with local drugs without prescribing systemic drugs is futile.

For local therapy, creams, ointments, and varnishes are used:

• antifungals: itraconazole, terbinafine, amorolfine, ketoconazole, clotrimazole, miconazole, econazole, oxyconazole, naftifine, natamycin, chloronitrophenol;
• local antiseptics: iodine, quinozol, dye solutions;
• multicomponent preparations based on an antifungal component in combination with an antiseptic, anti-inflammatory, etc.

Photo 1. Structure of the nail. Nail damage often begins at its edge and gradually spreads to the nail bed and its matrix.

Systemic therapy for onychomycosis

Systemic drugs provide penetration of the antifungal agent into the nail bed, but are not able to create high concentrations compared to local drugs. The reason for this is the high hepatotoxicity of systemic antifungal drugs and the need for their long-term use. Intraconazole, terbinafine, naftifine, and amorolfine are used to treat onychomycosis. In addition to high toxicity, long-term use of antifungal drugs leads to a decrease in immunity; after stopping the drug, re-infection is possible.

To reduce the side effects of systemic therapy with antifungal drugs, treatment is combined with local agents. At the end of the course of systemic therapy, it is advisable to use local preventive treatment to restore immunity after taking systemic drugs and prevent reinfection.

Laser treatment of onychomycosis

A promising direction in the treatment of onychomycosis is the use of high-intensity lasers.

Advantages of laser therapy for onychomycosis:

• sufficient penetrating power of laser radiation;
• the ability to accurately dose the impact energy;
• safety;
• lack of habituation of flora.

To treat onychomycosis, lasers with wavelengths of 870 nm, 930 nm, 980 nm, 1,064 nm, 1,319 nm are used.

The penetration depth of the laser beam in the range of 800–1,064 nm can reach 7 mm, and this is quite enough to reach the nail bed. High-intensity laser radiation leads to the death of the fungus. As the nail grows, the affected nail plate is replaced by a healthy nail. This may take from 6 to 12 months.

To increase the efficiency and safety of the procedure, infrared sensors for remote temperature control are used at the point of influence, which allows you to accurately dose energy and maintain the necessary power parameters to ensure the effectiveness and safety of the procedure.

The effectiveness of treating nail fungus with laser reaches 88%.

Photo 2: Before and 5 months after one ClearSence treatment. Photo courtesy of Marla Quintana, RN

Forecast

Clinical studies show high results in the effectiveness of getting rid of fungus when taking systemic antifungal agents: 48–76%. But, unfortunately, these data are combined with discouraging figures for re-infection - from 10% to 53%. Fungal infection on the fingers has a more favorable prognosis than onychomycosis of the feet. Onychomycosis caused by mold fungi often does not respond to treatment with systemic antifungal drugs. Yellow longitudinal stripes along the edges of the nail or yellow areas of onycholysis in the central zone of the nail (dermatophytoma) are a sign of a poor response to treatment.

Prevention

An important condition for the success of treatment and durability of results is the prevention of re-infection of the nail. The patient must clearly understand that the treatment will have a stable effect if the achieved results are maintained for 1 year. For this purpose, it is necessary to follow the doctor’s recommendations depending on the method and chosen treatment tactics.

General recommendations aimed at eliminating the most common causes of onychomycosis:

• in case of immunodeficiency – correction of immunity;
• prevention of microtraumas of the feet and hands, elimination of dryness and calluses;
• for excessive sweating - use powders, treatment with botulinum toxin, change socks daily;
• When visiting the pool, sauna, shower, beach, etc., you should use individual closed rubber slippers and wipe your feet dry.