accurate diagnosis can only be made when both clinical and laboratory criteria are present
Poor prognositc factorssher
Area of nail involvment >50%
Significant lateral disease
Subungual hyperkeratosis >2 mm
White/yelow or orange/brown streaks in nail (includes dermatophytoma)
Total dystrophic onychomycosis (with matirx involvement)
Nonresponsive organisms (eg, Scytalidium mold)
Patients with immunosuppression
Diminished peripheral circulation
Nail changes can be nonspecific
Onycholysis
May result from trauma
Psoriasis
Subungual hyperkeratosis
Psoriasis
Nail-plate thickening
trauma
onychogryphosis
Lichen planus
psoriasis
Changes likely unrelated to onychomycosis
Longitudinal or transverse ridges
pits
onychoschia
dryness
Differential Diagnosis
Psoriasis
Neoplasms
Lichen Planus
Treatment
Topicals
Ciclopirox nail lacquer has only a 5.5% to 8.5% cure rate and a recurrence rate of 25% - 50% at 60 weeks
Gupta AK, Fleckman P, Baran R. Ciclopirox nail lacquer topical solution 8% in the treatment of toenail onychomycosis. J Am Acad Dermatol 2000; 43(suppl)S70-80
Oral meds
Dose therapy
Warshaw E, Fett D; Pulse Versus Continuous Terbinafine for Onychomycosis: A Randomized, Double-blind, controlled trial; J Am Acad Dermatol; Oct 2005, Vol 53(4); 578-584
standard, continuous therapy shown to be superior to pulse therapy
continuous dose group recieved 250mg daily for 3 months
Pulse dose group recieved 500mg daily for 1 week per month for 3 months
Cure rate of all 10 nails
Continuous therapy group - 25%
Pulsed therapy group - 15%
125mg terbinafine for 6 months reported to have a 89% rate of negative mycology at 6 months
Matsumoto T, Tanuma H, Kaneko S, Takasu H, Nishiyama S. Clinical and pharmacokinetic investigations of oral terbinafine in patients with tinea unguium. Mycoses 1995;38:135-44
26 published clinical studies for oral treatment show only 25% - 50% complete cure rate
Epstein E. How often does oral treatment of toenail onychomycosis produce a disease-free nail? An analysis of published data. Arch Dermatol 1998;134:1551-4
FDA reports only a 14% - 38% complete cure rate for approved oral agents
Surgical
Anectodal evidence suggests combination of avulsion and oral therapy (for more than 3 months), may acheive higher cure rates
may be useful especially in nails with clinical patterns which are typically more resistant
extensive onychauxis
lateral pattern
longitudinal spike
severe onycholysis
dermatophytoma
McInnes BD, Dockery GL. Surgical treatment of mycotic toenails. J Am Podiatr Med Assoc 1997;87:557-64
Gupta AK, Baran R, SummerbellR. Onychomycosis: Strategies to improve efficacy and reduce recurrence. J Eur Acad Dermatol Venereol 2002;16:579-86
Practical Considerations
Mycological cure signifies that the funtal infection has been successfully treated, however pt must understand at beginning of therapy that they will likely not have a 100% normal nail. Some residual changes will be present.
recurrence reported as high as 53%
References
Sher RK, Tavakkol A. Onychomycosis: Diagnosis and definition of cure. J Am Acad Dermatol June 2007;56(6):939-44