Onychomycosis
`Evaluation, Treatment Options,
`Managing Recurrence, and Patient Outcomes
`
`Tracey C. Vlahovic, DPM, FFPM RCPS (Glasg)
`
`KEYWORDS
` Onychomycosis  Efinaconazole  Tavaborole  Laser  Toenail
` Trichophyton rubrum  Mycosis  Tinea pedis
`
`KEY POINTS
` Onychomycosis is a common disease that requires effective management to prevent pro-
`gression to a severe and debilitating condition.
` Confirming the diagnosis of onychomycosis is paramount especially before starting a sys-
`temic medication.
` Onychomycosis can be managed with either topical or systemic agents, and new topical
`agents afford better options to tailor appropriate therapy for our patients.
` Combination therapy (topical and systemic) may be an important consideration in more
`difficult to treat patients. Prophylaxis with topical agents may help prevent disease
`recurrence.
` Treatment of coexisting tinea pedis is critical and a number of strategies may be used to
`minimize the long-term consequences of the disease.
`
`INTRODUCTION
`
`Onychomycosis is a common superficial fungal infection of the nails leading to discol-
`oration, nail plate thickening, and onycholysis. Mycotic nail disease is the most com-
`mon nail pathology worldwide, reaching all cultures and ethnicities. Onychomycosis is
`increasing, accounting for up to 90% of toenail and at least 50% of fingernail infec-
`tions.1 The most common etiology in the United States is owing to dermatophytes,
`typically Trichophyton rubrum and Trichophyton mentagrophytes.2 In Europe, T
`rubrum is the chief agent followed by T mentagrophytes and T interdigitale.3,4 Nonder-
`matophyte molds and yeasts also play a role with varying frequency.
`
`Disclosures: Advisor, speaker and investigator for Valeant and Pharmaderm.
`The authors acknowledge Brian Bulley, MSc, of Inergy Limited for medical writing support.
`Valeant Pharmaceuticals North America LLC funded Inergy’s activities pertaining to this article.
`Department of Podiatric Medicine, Temple University School of Podiatric Medicine, 148 North
`8th Street, Philadelphia, PA 19107, USA
`E-mail address: traceyv@temple.edu
`
`Clin Podiatr Med Surg - (2016) -–-
`http://dx.doi.org/10.1016/j.cpm.2016.02.001
`podiatric.theclinics.com
`0891-8422/16/$ – see front matter Ó 2016 Elsevier Inc. All rights reserved.
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`Because the initial diagnosis is predicated on the nail’s appearance, the diagnostic
`gold standard is direct microscopy (potassium hydroxide [KOH]) and fungal culture.
`However, visual nail plate changes are used to classify onychomycosis,5 including
`distal subungual (also known as distal lateral subungual onychomycosis [DLSO], the
`most common form), proximal subungual, superficial white, and total dystrophic.6
`Onychomycosis occurs in 10% of the general population, 20% of individuals
`60 years and older, and 50% of individuals over 70 years.6 Peripheral vascular dis-
`ease, immunologic disorders, and diabetes mellitus correlate with the increased prev-
`alence in older adults. The risk of onychomycosis is 1.9 to 2.8 times greater in persons
`with diabetes mellitus, and in patients with HIV infection prevalence rates range from
`15% to 40%.6 Other predisposing factors include older age, sex (male > female),
`genetic predisposition, tinea pedis (interdigital or moccasin types), peripheral arterial
`disease, smoking, nail trauma, inappropriate nail hygiene, and family background of
`onychomycosis and hyperhidrosis.6
`Adult patients constitute the bulk of those seeking treatment, but there are increasing
`numbers of pediatric cases, possibly owing to increasing childhood obesity and pedi-
`atric diabetes. With prevalence ranging from 0% to 2.6% worldwide, pediatric onycho-
`mycosis is relatively rare compared with adults, but still one of the most common nail
`disorders in children.7 DLSO is the most common type seen in children, followed by
`proximal subungual and white superficial. The most common pathogen is T rubrum.
`In the last several years, novel treatments and considerations regarding the diag-
`nosis and management of onychomycosis have arisen. This review discussed
`emerging conservative and surgical methods to treat the disease.
`
`PATIENT EVALUATION
`
`To evaluate a patient presenting with nail dystrophy, the practitioner should begin by
`completing a thorough history and physical evaluation. With treatment options ranging
`from systemic to surgical, knowledge of medical history, current medications, and
`family history will aid in the differential diagnosis and formulating the treatment plan.
`Key questions include: how long have you had the nail changes, is it painful, has it
`affected your quality of life? Daily shoe gear choices, work and athletic activities,
`and the home and work environments will all assist treatment plan selection. Level
`of immunosuppression, vascular status, and the ability to take oral or apply topical
`medication should be taken into account. Discussion and examination of any other
`skin rashes or conditions should be completed, because psoriasis and eczema can
`mimic mycotic nails.
`Visual assessment is imperative. Since the Zaias classification was proposed in
`1972, modifications have been proposed and published to reflect the wide array of
`dermatophytes, nondermatophyte molds, and yeasts as well as the complications
`of various patterns occurring in the same nail or other inflammatory diseases copre-
`senting with mycosis.8 Nail plate changes include DLSO where the invasion begins
`at the hyponychium and disturbs the distal nail bed; proximal subungual, where inva-
`sion begins proximally; superficial white, where the upper surface of the nail plate is
`first attacked8; total dystrophic, which describes total nail plate involvement and sur-
`rounding periungual tissue; and endoynx, which describes distal nail plate attack
`resulting in a deeper penetration of hyphae.
`In addition, the physician should determine how many toenails are involved on 1 or
`both feet, percent involvement of the nail, any biomechanically aggravating factors
`that could contribute to nail dystrophy (adductovarus fifth digit, hammertoe, or hallux
`abductovarus), and the presence of tinea pedis interdigitally or plantarly.
`
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`Onychomycosis
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`Approximately 50% of nail disease is caused by onychomycosis9; the remainder
`conditions that mimic onychomycosis, having similar signs and symptoms, include
`psoriasis, lichen planus, reactive arthritis, allergic/irritant contact dermatitis, and
`eczema. Other differential diagnoses include alopecia, nail changes secondary to
`biomechanical
`issues, melanoma (and other skin cancers), traumatic onycholysis,
`20-nail dystrophy, and pachyonychia.10–12
`Because not all presenting nail disease is mycotic, it is important to confirm with lab-
`oratory diagnosis if the treatment plan includes oral antifungal therapy, if there is
`concomitant skin disease difficult to distinguish in the nails, and if the patient has
`been on antifungal therapy previously and disease has recurred. Laboratory diag-
`nostic methods include direct microscopy (KOH test), nail plate biopsy for periodic
`acid Schiff stain, and fungal culture. Generally, KOH and fungal culture are done
`together; KOH shows the presence of hyphae, and culture the species present.
`Unfortunately, fungal cultivation is a slow process (4 weeks) and may generate
`false-negative results in 40% of the cases that are microscopically positive.13 As an
`alternative periodic acid Schiff stain involves sending nail plate (commonly referred
`to as, but not a true, biopsy) for staining to determine presence of dermatophytes. Pe-
`riodic acid Schiff staining provides quicker results and is more sensitive, whereas cul-
`ture is more specific (regarding species).14–16
`Standard mycological tests, KOH, and fungal culture may yield false-negative or
`false-positive results, and require time to verify the pathogens.17 Accurate diagnoses
`are often delayed owing to lack of both specific and rapid methods of pathogen iden-
`tification. When the mycological analyses are negative and the clinical picture is highly
`suggestive of onychomycosis, polymerase chain reaction (PCR) testing may be an op-
`tion.18 Antifungal drug efficacy and dosages may differ for different causative patho-
`gens, and it has been hypothesized that mixed and nondermatophyte onychomycosis
`may be cause for high rate of treatment failures.19 A rapidly sensitive method for
`detection and identification will better guide an appropriate treatment strategy. PCR
`detects a specific DNA sequence; moreover, fungi species-specific PCR diagnostic
`methods are available,20,21 deepening our understanding and treatment of onychomy-
`cosis.22 Because DNA is extremely resistant and can persist even in the absence of
`viable hyphae, DNA amplification techniques such as PCR may represent a useful
`addition to standard procedure.23 Time will tell how truly beneficial PCR will be both
`in the physician office and in clinical trials.
`
`PHARMACOLOGIC TREATMENT OPTIONS: FOCUS ON TOPICAL THERAPY
`
`Onychomycosis can be managed with topical or systemic agents. The current stan-
`dard of care is an oral antifungal agent (either terbinafine or itraconazole) because
`they are more effective than topical agents, owing to issues of penetrance into the
`nail apparatus with topical agents. Drug interactions and the risk of hepatic injury
`may limit their desirability, especially in the elderly where the disease is most
`prevalent.
`Guidelines suggest monotherapy with topical antifungals is limited to:
` Superficial white, except in transverse or striate infections,
` DLSO, except in the presence of longitudinal streaks, when less than 80% of the
`nail plate is affected with lack of involvement of the lunula, or
` When systemic antifungals are contraindicated.24
`Developing effective topical treatments for onychomycosis has been complicated
`by low permeation rates through the nail plate to the site of infection.25–28 The nail
`
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`Vlahovic
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`may be more permeable to agents formulated in an aqueous vehicle.29 Unlike ciclo-
`pirox and amorolfine nail lacquers, new topical agents, efinaconazole and tavaborole,
`are now available as solutions.
`Studied in separate trials with similar, but not identical inclusion criteria, reported
`complete cure rates of tavaborole were 6.5% to 9.1%.30 Efinaconazole results were
`15.2% to 17.8%.31 Mycologic cure rates were 53.4% to 55.2% for efinaconazole,
`whereas the mycologic cure for tavaborole was 31.1% to 35.9% (Table 1). Although
`much emphasis has been placed on the need for active ingredient to pass through the
`nail plate, recent data suggest that efinaconazole may reach the infection site after
`transungual and subungual application32,33; subungual delivery data with tavaborole
`is pending.
`Lacquer-based topical therapies are applied primarily to the exterior nail plate, with
`the drug reaching the infection site mostly through nail permeation.34–36 Efinacona-
`zole is applied to the clean, dry nail plate surface, lateral and proximal nail folds,
`hyponychium, and undersurface of the nail plate.37 Application to the hyponychium
`and ventral aspect of the nail plate may be important in patients wishing to continue
`to use nail polish.32 Although nail polish does not seem to influence efinaconazole
`penetration into the nail, it can become tacky with repeated application.38 Up to 4
`layers of nail polish does not seem to inhibit penetration of tavaborole either.39 In
`neither case has the impact of nail polish on efficacy been assessed, nor is it
`contraindicated.
`Because toenail growth progresses from proximal to distal, newly formed nail plate
`replaces diseased nail, a process that can take 12 to 18 months.39 Clinical trial data
`suggest that tavaborole and efinaconazole must be applied daily to the toenails for
`at least 48 weeks. Some patients may require treatment for considerably longer
`because of slow toenail growth, disease severity, or for other reasons. It is not known
`whether longer treatment regimens with tavaborole or efinaconazole would produce
`better efficacy results; however, higher cure rates after longer follow-up periods
`have been reported with other agents.40–42
`It is important that patients recognize that cure may not translate to a completely
`clear nail.43 Poor adherence with any long-term chronic therapy is well documented.44
`A number of post hoc analyses with efinaconazole have been carried out to better
`identify prognostic factors for treatment success. Gender45 and disease severity46
`were significant influencers of complete cure over the duration of the studies; female
`patients and those with milder disease may see results much quicker in clinical prac-
`tice, whereas male patients and those with moderately severe disease may require a
`longer treatment course, or combination therapy with oral antifungals. Although male
`patients are more difficult to treat, reasons are unclear. They tend to seek help for
`more advanced disease and suffer more nail trauma, and their toenails tend to be
`thicker. The reduced rate of growth and thickness of the nail may be factors in
`more severe disease, although it may be that these patients just require longer treat-
`ment courses.
`Tinea pedis is an important causative factor for onychomycosis, and better results
`are seen when any coexisting tinea pedis is also treated.47 In addition, managing tinea
`pedis is critical to minimizing disease recurrence.
`Onychomycosis remains a common, progressive, and difficult disease to manage
`successfully. Early diagnosis and treatment are important irrespective of risk factors
`or comorbidities.48 A multidirectional approach to drug delivery may broaden the utility
`of topical therapies, such as efinaconazole in the treatment and greater clinical expe-
`rience will help to guide management practice.
`
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`Onychomycosis
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`5
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`Completecureandmycologiccureratesafter48weeks’dailytherapy,4-weekfollow-updata(P<.001forallactivedatavsrespectivevehicledata).
`
`12.2
`
`1.5
`(n5205)
`Vehicle
`
`35.9
`
`7.2
`
`9.1
`(n5396)
`Tavaborole
`TavaboroleClinicalStudies30
`
`0.5
`(n5194)
`Vehicle
`
`31.1
`
`6.5
`(n5399)
`Tavaborole
`
`16.9
`
`5.5
`(n5201)
`Vehicle
`
`53.4
`
`15.2
`(n5580)
`Efinaconazole
`
`16.8
`
`3.3
`(n5214)
`Vehicle
`
`55.2
`
`Mycologic(%)
`
`17.8
`(n5656)
`Efinaconazole
`
`Complete(%)
`
`Cure
`
`EfinaconazoleClinicalStudies31
`
`Efficacyresultsfromrecentclinicaltrialswithefinaconazoleandtavaboroleinmildtomoderateonychomycosis
`Table1
`
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`NONPHARMACOLOGIC TREATMENTS
`
`length and thickness using nail
`Debridement, the mechanical reduction of toenail
`nipper or rotating burr, may provide a valuable adjunct for patients experiencing
`pain upon ambulation and in shoe gear.49 Although debridement alone improves qual-
`ity of life and nail thickness, it does not result in mycological cure.50 Topical ciclopirox
`and debridement improved patient’s quality of life and resulted in mycologic cure.50
`However, debridement added to oral antifungal therapy may offer a only a small
`benefit.51,52 Debridement can provide pain relief and improved patient satisfaction,
`affording an opportunity to encourage adherence. It may offer benefits through
`reduced fungal load, and enhanced penetration of topical drugs into the nail unit.
`For patients who opt against pharmacologic treatment, debridement will allow more
`comfort in shoe gear and reduce potential pressure on the nail bed, especially if dia-
`betic neuropathy is present.
`Nail avulsion, the separation of the nail plate from the nail bed, can be achieved non-
`surgically with daily application of topical 40% urea for 1 to 2 weeks.53 Generally, this
`is followed by application of a topical antifungal once the toenail has been removed,
`repeating as necessary. It is more common in Europe.53 Nail avulsion can be useful
`in patients who have a needle/procedure phobia, who have peripheral vascular dis-
`ease or another comorbidity precluding pharmacologic intervention, or have a single
`nail infected. However, removal of the nail itself will not result in clearance of the infec-
`tion, even when followed by topical antifungal therapy.
`Management of onychomycosis is a long-term challenge for some patients owing to
`the rate of recurrence and reinfection. Many do not want to add another oral medica-
`tion to their regime, or use a daily topical product for a year. Laser therapy is a nonsur-
`gical, nonpharmacologically based option. Approved devices include Nd:YAG
`1064 nm lasers and a diode at 870/930 nm.54 The US Food and Drug Administration
`approved laser treatment of certain wavelengths to “temporarily improve the appear-
`ance of the nail,” making no claims regarding mycological cure owing to device
`approval being based on substantial equivalence to already existing devices on the
`market.54 The mechanism of action is unknown, but proposed to be bulk heating of
`the nail unit selectively destroying fungal elements.54 In the onychomycosis laser
`studies, the definition of “cure” and number of treatments are extremely variable,
`and the fluence (energy applied per surface area) differs from device to device. Con-
`sistency within studies on mycological diagnosis varies, and strictness of a pharma-
`ceutical clinical trial lacking. It is difficult to extrapolate settings used on the nail, the
`length of treatment, and outcomes owing to the differences in just the Nd:YAG laser
`class. Most likely patients who opt to receive laser as monotherapy will need several
`treatments over a 12- to 16-month period owing to the lack of recurrence data and
`possibility for reinfection.54,55 It has potential as an adjunct to both oral and topical an-
`tifungals, but further research is needed to show efficacy.
`
`COMBINATION THERAPY
`
`New topical antifungals and device-based therapies have expanded therapeutic op-
`tions in onychomycosis. Combination therapy with multiple drug classes and routes
`of administration may improve overall efficacy especially in patients proven difficult
`to treat successfully with more traditional methods.
`The rationale for the combination of topical and oral therapy in the treatment of ony-
`chomycosis is that systemic antifungals reach the infection via the nail bed, and
`topical agents are absorbed through the nail surface.56 In addition, some topical
`agents may reach the site of infection via the hyponychium. Ideally, combined
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`Onychomycosis
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`antifungals should be synergistic in their mode of action and specific activity against
`the types of fungal infection seen in onychomycosis.
`Combination therapy can be used sequentially or in parallel. In patients likely to fail
`therapy (ie, those with diabetes or having yellow spikes in the nail), parallel treatment is
`invaluable. Sequential treatment (ie, treating initially with an oral agent and following
`up with topical treatment) may be helpful in patients who show a poor response to
`treatment.57
`Combination therapy with oral and lacquer-based topical antifungals has been
`shown to lead to a marked improvement of mycological and clinical outcomes asso-
`ciated with onychomycosis,35,43,58,59 and may be more cost effective than using a sys-
`temic agent alone.43 Currently, there are no data with the newer solution-based topical
`agents (eg, efinaconazole and tavaborole) used in combination with an oral agent to
`treat onychomycosis and data are eagerly awaited given the apparent superior effi-
`cacy as monotherapy. Data on the combined use of an oral agent and laser therapy
`also suggest a more rapid and effective clinical outcome in patients with
`onychomycosis.60
`
`SURGICAL TREATMENT OPTIONS
`
`For a singularly painful or thickened nail, some patients may opt for total nail removal.
`Surgery involves application of local anesthesia to the digit followed by removal of the
`nail plate in toto. Simple total avulsion of the nail itself is not curative for a mycotic nail,
`because the procedure does not address the basis of infection. Combining nail avul-
`sion and topical antifungals has been described as the preferred treatment plan. Total
`nail avulsion with the use of a topical azole cream applied twice-daily to the exposed
`nail bed resulted in a high dropout rate. All patients with total dystrophic onychomy-
`cosis failed, and only 56% of patients (15/27) were cured with this approach,61 sug-
`gesting that the procedure should not be generally suggested for the treatment of
`onychomycosis.
`Nail avulsion has been suggested to obtain a better specimen for fungal culture, but
`should only be used in situations where both systemic and topical antifungal therapies
`have failed.53 Contraindications include patients with peripheral vascular disease,
`autoimmune disorders, collagen vascular disease, diabetes, hemostasis disorders,
`and acute infection/inflammation of the periungual tissue.62 Possible keratinization
`of the nail bed as the nail plate is growing is also a concern.
`
`MANAGEMENT OF RECURRENCE
`
`Despite the number of available treatment options, not all onychomycosis patients are
`cured, or will remain cured. Recurrence (either as a result of relapse or reinfection) is
`not uncommon, seen in 10% to 53% of patients63; rates increase with increasing post-
`treatment period.
`Several factors may play a role although it is not known which are the most
`important:
` Family history;
` Age;
` Occupation;
` Lifestyle;
` Environmental conditions;
` Underlying nail physiology (ie, presence of a very thick nail, extensive involve-
`ment of the entire nail unit, lateral nail disease and yellow spikes);
`
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` Physical trauma, especially in the elderly;
` Concomitant disease (eg, peripheral vascular disease and diabetes);
` Presence of tinea pedis; and
` Immunosuppressed patients.
`Only coexisting diabetes mellitus has been shown to have a significant negative
`impact on recurrence rates (P 5 .026).60 Although recurrence rates were higher with
`greater nail involvement (>50%; P 5 .01) and age (>60 years; P 5 .18), these were
`not significant.64
`Few studies have followed the clinical course of patients beyond 12 months after
`systemic or topical therapy.65,66 With systemic therapy, recurrence has been shown
`to be more common with itraconazole than terbinafine, although in both cases the
`rates increase with posttreatment interval.67,68 Mean time to recurrence after success-
`ful treatment was 36 months in a 7-year prospective study of 73 successfully treated
`onychomycosis patients.66 Other factors, including presence of predisposing factors,
`use of nail lacquer as a prophylactic treatment, and isolated dermatophyte strain were
`not related significantly to relapse.66 The long-term benefits of terbinafine are probably
`related to its fungicidal action, compared with the fungistatic action of itraconazole.69
`There are no good data on recurrence rates with topical therapy, where follow-up
`after cessation of treatment in clinical trials was limited to 4 weeks. Data from the clin-
`ical trials on efinaconazole and tavaborole show complete cures rates continuing to
`increase posttreatment, suggesting recurrence may not a problem in the immediate
`term. A study of 207 patients successfully cured and followed for 12 months after
`completion of therapy included 6 patients treated with amorolfine nail lacquer. Recur-
`rence rates (33.3%) were similar to those seen with terbinafine (38.5%) and itracona-
`zole (34.3%).64
`Data on the prevention of recurrence with topical therapy is limited. A small open-
`label study (n 5 52) with amorolfine prophylaxis in patients previously cured with ter-
`binafine or terbinafine and amorolfine showed statistical significant results compared
`with untreated controls (P 5 .047). These data suggest a modest benefit that does not
`seem to be sustained. Relapse rates at month 12 were 8.3% and 31.8% respectively;
`however, by month 36 differences were not significant, and had occurred in 29.2% of
`the patients treated prophylactically with twice-weekly amorolfine.70 A 2-year study in
`48 patients found that biweekly use of miconazole powder 2% to prevent recurrence
`showed no difference between active and placebo.70 A subsequent case report was
`able to demonstrate sustained remission from onychomycosis with once-weekly mi-
`conazole cream applied to the affected toe and toe clefts.71
`The optimal dosing regimen or duration of prophylaxis with topical agents is un-
`known, although data from other long-term recurrence studies with systemic treat-
`ments suggest 2 to 3 years.72 Amorolfine prophylaxis was dosed twice weekly, and
`it is not known whether more frequent dosing would have resulted in greater protec-
`tion from recurrence.66 Amorolfine can be detected in the nail for about 2 weeks, and
`normal dosing to treat onychomycosis is to apply to the nail plate once or twice a
`week.73 High concentrations of efinaconazole have been shown to remain in the nail
`plate for at least 2 weeks after cessation of therapy,74 suggesting the potential for
`twice weekly prophylaxis. The lack of benefit beyond 12 months may be a function
`of poor adherence, or infrequent dosing.
`Prophylaxis in diabetic patients with onychomycosis would seem to be very impor-
`tant, given the high relapse potential and risk of complications. In addition to treating
`immediate family members to help spread of disease, encouraging patients prone to
`tinea pedis to self-treat is critical.
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`Onychomycosis
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`9
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`EVALUATING PATIENT OUTCOMES AND LONG-TERM MANAGEMENT
`
`There have been a number of discussions of onychomycosis cure in the literature; yet
`there remains no agreement on definition of treatment success.
`The clinical trial definition of complete cure is probably too stringent.75,76 A
`consensus conference proposed 2 alternative criteria: 100% absence of clinical signs
`of onychomycosis (mycology not required), or negative mycological laboratory results
`with 1 or more of the following clinical signs: distal subungual hyperkeratosis or ony-
`cholysis leaving less than 10% of nail plate affected, or nail plate thickening that does
`not improve with treatment because of comorbid condition.2 More recently, it has
`been suggested that absence of clinical signs after an adequate washout period,
`coupled with negative culture, with our without negative microscopy, should be
`considered as a cure.76
`These definitions raise a number of important considerations. In some patients,
`complete cure may not be a realistic option, and yet both physician and patient
`may be still happy with the outcome. In addition, a longer treatment duration (12–
`18 months) may produce a better clinical outcome; however, adherence may become
`a significant issue.77 Longer washout periods of 3 to 6 months, while allowing for the
`removal of both residual drug and nonviable fungal cells to afford a more accurate
`interpretation of mycological outcome, increase the risk of recurrence.77
`Evaluating clinical outcomes should be done with reference to baseline severity, and
`patients are encouraged to take pictures of their toenails at regular intervals. Because
`it is also common for other toenails to be affected, and occasionally both feet, it has
`been suggested that efficacy should be based on clinical improvement in all involved
`onychomycotic toenails.78
`Patient outcomes in onychomycosis after appropriate treatment are generally good.
`There are some patients who will never have a completely clear nail, or nails. Others do
`not respond to topical or systemic antifungal therapy; reasons may be multifactorial
`and unclear. In some cases, combination therapy or repeated courses of antifungals
`may be required.
`Given that it may be 12 to 18 months before the nails grow out fully, and the signif-
`icant treatment commitment, long-term recommendations to maintain clear nails are
`important. In controlled clinical trial environments recurrence rates are very high and
`increase with posttreatment interval. In clinical practice the number of onychomycosis
`patients suffering recurrence is likely to be higher, with suboptimal treatment. Howev-
`er, there are a number of steps patients can take to minimize risk. Prophylactic use of
`antifungal agents should be encouraged on a regular basis for patients suffering
`persistent infection. Twice weekly applications may be effective, although it is not
`certain whether prophylaxis beyond 1 year is cost effective or desirable without other
`preventative measures. Treating other family members with the disease, and treating
`any tinea pedis is likely to minimize recurrence significantly.
`In addition, footwear and sock decontamination remain an important consideration
`because these items can act as a fungal reservoir. It has been shown that at least 10%
`of patients with tinea pedis and onychomycosis are at risk of reinfection by contact
`with their socks.79 Footwear can be decontaminated with antifungals, ultraviolet light,
`or potentially ozone.80–83 Patients should also try to avoid activities known to risk
`spread of disease such as swimming and washing clothes (especially socks) in cold
`water.84
`Successful treatment of onychomycosis can be a challenge and long-term recom-
`mendations are critical in such a chronic, recurring condition. A number of strategies,
`both therapeutic and practical can be used successfully.
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`10
`
`Vlahovic
`
`SUMMARY
`
`In the past 2 years, onychomycosis has become a hot topic again in both podiatric
`medicine and dermatology owing to the introduction of 2 new topical antifungals (efi-
`naconazole and tavaborole). As these are novel agents in treating mycotic nails, it also
`allows one to go back and revisit the other options already available: systemic,
`nonsurgical, and surgical. With the vast amount of therapeutic possibilities out there
`(that also have an array of cure rates and complications), it is important for the clinician
`to choose the best option for the patient’s situation and nail disease. Of most impor-
`tance, confirming the diagnosis of onychomycosis is paramount, especially before
`starting a systemic medication. Choosing other modalities to treat the nail, whether
`as monotherapy or as a combination regime, should be tailored to each patient. Over-
`all, the clinician has more options than ever to manage fungal nail disease and ulti-
`mately improve quality of life for these patients.
`
`REFERENCES
`
`1. Ghannoum MA, Hajjeh RA, Scher R, et al. A large-scale North American study of
`fungal isolates from nails: the frequency of onychomycosis, fungal distribution,
`and antifungal susceptibility patterns. J Am Acad Dermatol 2000;43:641–8.
`2. Thomas J, Jacobson GA, Narkowicz CK, et al. Toenail ony