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Update on
Management of
Dermatophytoses
Reviewing principles of diagnosis and management and understanding the latest therapeutic
developments can lead to improved outcomes.
By Joseph Bikowski, MD, FAAD
T
inea corporis and tinea pedis are reportedly the
most common dermatophytoses in the US and
are each estimated to affect approximately 20
percent of the population, however true incidence
may be understimated.1 Some dermatophyte infections
are more common in certain populations. For example,
tinea pedis, tinea cruris or “jock itch,” and tinea corporis
are more common complaints among athletes than is
onychomycosis. In contrast, onychomycosis affects an
estimated 12 percent of the US population; Incidence
increases with age and is highest among those over age
65.2 Both tinea pedis and onychomycosis are more common in those with diabetes.3
Diagnosis of tineas tends to be straightforward for specialists, and the diagnosis can be confirmed with KOH
preparation. Note that contact dermatitis of the feet or
hands may mimic tinea pedis or manuum, respectively,
and must be considered in the final diagnosis. Of note, a
dermatitis that develops on both hands and both feet is
more likely to have a systemic cause rather than to be a
contact dermatitis.4 Conversely, involvement of two feet
and one hand suggests a primary fungal infection of the
foot that has been transferred to one hand only.5 It is
unknown why the other hand is not involved. Other similar presentations include one foot/two hands, and even
one foot/one hand.
Diagnostic Pearl:
If the webspace between the fourth and fifth toe is spared,
consider a diagnosis other than tinea.
Interdigital type tinea pedis is one of three primary presentations
of tinea pedis. The others are vesiculobullous type tinea pedis
and plantar moccasin type.
Superficial cutaneous yeast infections may be predominantly caused by Candida. Among immunocompetent individuals, candidiasis may be especially common in the inframammary folds or genital crease region (more so for women
than men). Culture can be used to distinguish Candidiasis
from dermatophytosis. Topical antimycotics are standard
treatment for candidiasis, particularly clotrimazole or ketoconazole. Oral fluconazole is the primary systemic agent
with anti-Candida activity.
February 2014
PRACTICAL DERMATOLOGY 23
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Topical AntiFUNGALS
Drug
Brand Name(s) Example
Vehicle
Butenafine 1%
Mentax, Sinphar
Cream
Econazole nitrate 1%
Cream, lotion
Luliconazole 1%
Luzu, Valeant
Cream
Ketoconazole 2%
Xolegel, Aqua Pharmaceuticals
Cream, gel
Naftifine 1%
Naftitine 2%
Naftin, Merz
Cream (Tube and 1% Pump),
Gel (Tube)
Oxiconazole nitrate 1%
Oxistat, PharmaDerm
Cream, lotion
Sertaconazole nitrate 2%
Ertaczo, Ortho Dermatologics
Cream
Sulconazole nitrate
Exelderm, Ranbaxy Laboratories
Cream, solution
Diagnostic Pearl:
Tinea Cruris is rarely if ever seen in women.
Most tineas can be managed with topical antifungals
(Table 1). Treatment must be selected that is expected to
address the causative organism and in a vehicle formulation that the patient can easily apply to the treatment site.
A broad-spectrum antifungal is preferred.6 Oral antifungals
typically are reserved for extensive or chronic involvement
or when application of a topical agent is physically challenging for the patient.7
New to the market is a novel azole called luliconazole,
available in a 1% cream (Luzu, Valeant) for the management
of interdigital tinea pedis or tinea corporis. The key feature
of this formulation is its dosing schedule. For the treatment
of tinea pedis, luliconazole cream is applied once-daily for
two weeks. For the treatment of tinea cruris, it is applied
once-daily for one week.
Also new to the market are new 2% cream and gel formulations of naftifine (Naftin, Merz) for the treatment of
interdigital tinea pedis, tinea cruris, or tinea corporis. It is
indicated for once-daily application for two weeks in all
three indications.
Prophylactic topical antifungal therapy applied at intervals may be indicated for those at high risk for or with a
history of recurrence of dermatophytosis, although this is an
off-label use.
Treatment of tineas is important for reasons beyond symptom control. Tinea pedis or manuum may provide a reservoir
of dermatophytes leading to onychomycosis, though in some
cases nail involvement is a primary presentation.
Update on Onychomycosis
In contrast to tineas of the skin, most cases of onychomycosis require oral therapy. Development of topical therapies for
24 PRACTICAL DERMATOLOGY
February 2014
onychomycosis has proven challenging, due to the difficulty
of penetrating the nail plate to deliver drugs to the nail bed,
the site of infection. The lengthy period the nail takes to grow,
the hardness of the nail plate, and location of the infection
between the nail bed and plate are major contributing factors.
Poor nail penetration is the main factor limiting the
use of topical antifungal agents in the treatment of onychomycosis, and directly relates to the nail plate’s unique
properties: its thickness and relatively compact cellular
structure.8,9,10
Currently, systemic antifungal therapy with terbinafine
or itraconazole is the mainstay of treatment. FDA last year
issued a warning about potential risks associated with ketoconazole, including potentially fatal liver injury and risk of
drug interactions and adrenal gland problems, and indicated
that the agent should not be used as a first-line treatment
option for fungal infections. Systemic terbinafine and itraconazole are shown to be effective and generally safe for the
management of onychomycosis, but there are potential risks
associated with therapy.11
Mycologic cure (i.e., the eradication of the causative
organism proven by negative culture) is widely accepted
as the main treatment goal, with complete clinical clearing occurring after this stage has been achieved.12 Reported
PRACTICAL POINTER
Treatment of tineas is important for reasons beyond symptom control. Tinea pedis or manuum may provide a reservoir
of dermatophytes leading to onychomycosis, though in
some cases nail involvement is a primary presentation. • In
contrast to tineas of the skin, most cases of onychomycosis
require oral therapy. Development of topical therapies for
onychomycosis has proven challenging, due to the difficulty
of penetrating the nail plate to deliver drugs to the nail bed,
the site of infection.
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mycologic cure rates in the phase III studies for oral itraconazole and terbinafine were 54 percent and 70 percent,
respectively.13,14 Relapse may occur in up to one fifth of
those treated with terbinafine, and one-quarter of those
treated with itraconazole. Relapse has been attributed to
chronic or recurrent tinea pedis, genetic predisposition, and
re-exposure to pathologic organisms.15
Diagnostic Pearl:
Onychomycosis of the fingernails in the absence of
toenail involvement is virtually non-existent.
Common side effects of terbinafine include gastrointestinal upset, headache, and minor rashes. Serious side
effects are reported in less than one percent of patients,16
but include serious or even fatal liver toxicity one in 54,000.
Thus, systemic therapy is not recommended in patients
with chronic or active liver disease, and liver-function testing is advisable. Monitoring liver function at four to six
weeks is recommended by several experts.17 The side effects
of itraconazole are similar to those of terbinafine but also
include congestive heart failure, which represents a contraindication.
Relatively new to the market is Onmel (Merz), a new oncedaily 200mg single tablet formulation of itraconazole indicated for the oral treatment of onychomycosis of the toenail
caused by Trichophyton rubrum or T. Mentagrophytes in
non-immunocompromised patients. The tablets are manufactured with what is described as a “melt extrusion” or Meltrex
Technology that enables the single tablet formulation.
Ciclopirox 8% nail lacquer is the only topical treatment
currently approved by the FDA for the treatment of onychomycosis.
Currently under FDA review, efinaconazole 10% solution is the first triazole antifungal specifically developed for
the topical treatment of mild to moderate distal subungal
onychomycosis. It is believed that low surface tension of
the alcohol-based formulation helps efinaconazole to first
penetrate through the nail plate, then access the nail bed
by wicking into the air gap and spreading over the site of
infection.18
In two large pivotal trials involving 1,655 patients, mycologic
cure was 56 percent, and significantly greater than vehicle
(Figure 1, P<.001). Clinical treatment success (0 percent to ≤10
percent area disease involvement of the affected toenail) was
achieved in 43 percent of patients. Given that the majority
of patients had ≥40 percent affected area involvement of the
great toenail at baseline, this represents a meaningful improvement for the onychomycosis patients in the studies. Mild, transient irritation at the site of application was the most common
adverse event in two percent of study patients.
26 PRACTICAL DERMATOLOGY
February 2014
Diagnostic Pearl:
An off-label topical treatment option for distal subungual onychomycosis is a topically applied, low-viscosity,
alcohol-based antifungal solution (sulconazole nitrate 1%,
Exelderm, Ranbaxy Laboratories).
Therapeutic success requires that the patient deliver
the solution directly into the nail bed by placing the toe or
fingernail in an upright position then instilling one to two
drops subungually between the nail plate and nail bed.
The patient should hold the toe or finger in an upright
position for 30 seconds, to allow gravity to pull the active
agent into the nail bed. Treatment should be applied twice
daily. Coexistent tinea pedis or manuum must be managed to minimize the risk of re-infection of the nail.
Despite successful elimination of fungus from the nails,
patients undertaking treatments for toenail onychomycosis
should be advised that successful eradication of fungus from
the nail may not necessarily restore a toenail to a normal
appearance, as it may have been damaged and dystrophic
before the infection occurred.
Checking the foot for early signs of re-infection is key so
that topical treatment can be instigated at an early stage.
Maintenance therapy at proper intervals may also be indicated, though not formally studied. n
Dr. Bikowski has served as an advisory board
member/consultant to Promius Pharma.
Joseph Bikowski, MD, FAAD is Director of
Bikowski Skin Care Center in Sewickley, PA.
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2. Scher RK, Rich P, Pariser D, Elewski B. The epidemiology, etiology, and pathophysiology of onychomycosis. Semin Cutan
Med Surg. 2013 Jun;32(2 Suppl 1):S2-4.
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2009 Jul;27(3):281-7.
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Acad Dermatol Venereol 2005;19 suppl 1:25–33.
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13. Sporanox (itraconazole) [package insert]. Janssen Pharmaceuticals Inc, Titusville, NJ; 2012.
14. Lamisil (terbinafine HCl) [package insert]. Novartis Pharmaceuticals Corporation, East Hanover, NJ; 2012
15. Tosti A, Piraccini BM, Stinchi C, et al. Relapses of onychomycosis after successful treatment with systemic antifungals: a
3-year follow-up. Dermatology 1998;197:162–166.
16. O’Sullivan DP, Needham CA, Bangs A, et al. Postmarketing surveillance of oral terbinafine in the UK: report of a large
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