Journal of Drugs in Dermatology

Toenail onychomycosis is a common disease in which treatment options are limited and treatment failures and disease recurrence are frequently encountered.

It usually requires many months of treatment and recurrence may occur in more than half of the patients within 1 year or more after the infection has been eradicated. 

Recurrence (relapse or re-infection) in onychomycosis is common, occurring in 10% to 53% of patients. Effective management of onychomycosis usually requires many months of treatment.

Recurrence can arise 1 year or more after the infection was eradicated and is commonplace, possibly affecting more than half of the patients who have been treated successfully. 

Managing onychomycosis is a significant long-term commitment for any patient, and minimizing recurrence is critical to meet their expectations.

TAKE-HOME MESSAGE

This review article highlights treatment strategies to minimize onychomycosis recurrence.

Onychomycosis is a progressive disease associated with a number of clinical sequelae. Successful treatment depends on an accurate diagnosis and patient adherence to long-term therapy, as well as the recognition that recurrence is commonplace and will likely require follow-up treatment.

How Common Is Relapse or Recurrence of Disease?

A 7-year prospective study of onychomycosis patients who were successfully treated (mycological and clinical cure) with continuous terbinafine or intermittent itraconazole showed that recurrence occurred at a mean time of 36 months after successful treatment.

A meta-analysis of five trials found that relapses (defined as occurring more than 2 years after the end of therapy) were more common after treatment with itraconazole (intermittent or continuous) compared to continuous terbinafine. 

The long-term benefits of terbinafine are probably related to its fungicidal action, compared with the fungistatic action of itraconazole.

While the fungicidal activity of terbinafine may explain this finding, the difference is often not significant.

What Factors Influence Recurrence?

It is important for clinicians to know that patients with a genetic predisposition, the elderly, immunocompromised, and those with diabetes are more likely to experience re-infection of onychomycosis.

– Family history and occurrence of onychomycosis or tinea pedis in family members

– Lifestyle including wearing occlusive footwear and moist environments such as health clubs and swimming pools

– Diabetes was associated with a significantly higher relapse rate in patients with onychomycosis

– Therapy choice, duration, treatment success, and adherence

– Properties and Types of the infecting fungus

– Environmental conditions and nail injuries

Can Recurrence Be Prevented with Topical Prophylaxis?

The use of topical antifungal lacquers or solutions to prevent recurrence of onychomycosis following complete cure has been suggested by various authors.

Topical prophylaxis once weekly or twice monthly would seem appropriate in those patients most at risk.

It is possible that a maintenance regimen of topical therapy may either prevent or reduce recurrence. Data suggest that prophylaxis may need to be continued for up to three years for optimal effect

Practical Approaches to Minimize Relapse and Recurrence

– Patient education to improve adherence and recognize early signs of disease recurrence

– Discarding or disinfecting old footwear and socks

– Clipping nails short

– Keeping feet cool and dry

– Avoiding going barefoot in public places

– Topical antifungal prophylaxis

– Prompt treatment of any tinea pedis, including that of family members