Search Results
Abstract
Background: Onychomycosis is the most common nail disease seen in clinical practice. Medication safety, severity of disease, co-morbidities, concomitant medications, patient age, and cost are all important considerations when treating onychomycosis. Since cost may affect treatment decisions, we sought to analyze Medicaid formulary coverage of onychomycosis antifungals.
Methods: Public state Medicaid formularies were searched for coverage of FDA approved onychomycosis medications and off-label oral fluconazole. Total drug cost for a single great toenail was calculated using National Average Drug Acquisition Cost. Pearson correlation coefficients were calculated to compare coverage and cost, mycological cure rate, and complete cure rate.
Results: Oral terbinafine and off-label fluconazole were widely covered for onychomycosis treatment. There was poor coverage of oral itraconazole and topical ciclopirox, and no coverage of topical efinaconazole and tavaborole without step-edits or prior authorization. There was a significant negative correlation between medication coverage and cost (r = −0.758, p= 0.040). There was no correlation between medication coverage and mycologic (r = 0.548, p = 0.339) and complete (r = 0.768, p = 0.130) cure rates.
Conclusions: There is poor Medicaid coverage of antifungals for the treatment of onychomycosis, with step-edits and prior authorization based on cost rather than treatment safety and efficacy. We recommend involving podiatrists and dermatologists in developing criteria for insurance approval of onychomycosis treatments.
Onychomycosis Infections
Do Polymerase Chain Reaction and Culture Reports Agree?
Background:
Mycological culture is the traditional method for identifying infecting agents of onychomycosis despite high false-negative results, slower processing, and complications surrounding nondermatophyte mold (NDM) infections. Molecular polymerase chain reaction (PCR) methods are faster and suited for ascertaining NDM infections.
Methods:
To measure agreement between culture and PCR methods for identification of infecting species of suspected onychomycosis, single toenail samples from 167 patients and repeated serial samples from 43 patients with suspected onychomycosis were processed by culture and PCR for identification of 16 dermatophytes and five NDMs. Agreement between methods was quantified using the kappa statistic (κ).
Results:
The methods exhibited fair agreement for the identification of all infecting organisms (single samples: κ = 0.32; repeated samples: κ = 0.38). For dermatophytes, agreement was moderate (single samples: κ = 0.44; repeated samples: κ = 0.42). For NDMs, agreement was poor with single samples (κ = 0.16) but fair with repeated samples (κ = 0.25). Excluding false-negative reports from analyses improved agreement between methods in all cases except the identification of NDMs from single samples.
Conclusions:
Culture was three or four times more likely to report a false-negative result compared with PCR. The increased agreement between methods observed by excluding false-negative reports statistically clarifies and highlights the major discord caused by false-negative cultures. The increased agreement of NDM identification from poor to fair with repeated sampling along with their poor agreement in the single samples, with and without false-negatives, affirms the complications of NDM identification and supports the recommendation that serial samples help confirm the diagnosis of NDM infections.
Topical Treatments for Onychomycosis
A Historical Perspective
Topical treatment of onychomycosis, in contrast to systemic oral therapy, allows the patient to apply medication directly to the affected area, thereby decreasing the potential for adverse events and drug interactions. Historically, several topical antifungal agents have been used in the treatment of onychomycosis; however, the evidence for their effectiveness is based on very limited data or anecdotal reports. Recently, the development of new, effective topical agents has renewed interest in this form of therapy. As clinical experience with newer topical agents expands, they may be found to be an effective option for the treatment of onychomycosis. (J Am Podiatr Med Assoc 93(2): 136-141, 2003)
Therapies for Onychomycosis
A Systematic Review and Network Meta-analysis of Mycological Cure
New therapies for onychomycosis continue to be developed, yet treatments are seldom directly compared in randomized controlled trials. The objective of this study was to compare the rates of mycological cure for oral and topical onychomycosis treatments using network meta-analysis. A systematic review of the literature on onychomycosis treatments published before March 25, 2013, was performed, and data were analyzed using network meta-analysis. Terbinafine, 250 mg, therapy was significantly superior to all treatments except itraconazole, 400 mg, pulse therapy; itraconazole, 200 mg, therapy was significantly superior to fluconazole and the topical treatments; and fluconazole, efinaconazole, ciclopirox, terbinafine nail solution, and amorolfine treatments were significantly superior to only placebo. These results support the superiority of 12-week continuous terbinafine, 250 mg, therapy and itraconazole, 400 mg, pulse therapy (1 week per month for 3 months) while suggesting the equivalence of topical therapies. These results reflect findings from the literature and treatment efficacy observed in clinical practice.
Satisfaction with Onychomycosis Treatment
Pulse versus Continuous Dosing
The purpose of this study, which involved two dermatology clinics and two podiatric medical clinics, was to determine whether a difference exists in patient-reported satisfaction and compliance between continuous terbinafine therapy and pulse-dose itraconazole therapy for the treatment of toenail onychomycosis. Patients in this multicenter, open-label, cross-sectional study had previously completed treatment with either oral terbinafine or oral itraconazole for toenail onychomycosis. Patients were interviewed by telephone to assess clinical outcomes, compliance, and satisfaction with treatment; clinical data were collected by medical chart review. Patients reported significantly greater ease and convenience of treatment and higher overall satisfaction with continuous terbinafine therapy compared with pulse-dose itraconazole therapy. (J Am Podiatr Med Assoc 93(5): 373-379, 2003)
Fungal Diversity and Onychomycosis
An Analysis of 8,816 Toenail Samples Using Quantitative PCR and Next-Generation Sequencing
Background:
Onychomycosis is a fungal infection of the nail that is often recalcitrant to treatment and prone to relapse. Traditional potassium hydroxide and culture diagnosis is costly and time-consuming. Therefore, molecular methods were investigated to demonstrate effectiveness in diagnosis and to quantify the microbial flora present that may be contributing to disease.
Methods:
A total of 8,816 clinically suspicious toenail samples were collected by podiatric physicians across the United States from patients aged 0 to 103 years and compared with a control population (N = 20). Next-generation sequencing and quantitative polymerase chain reaction were used to identify and quantify dermatophytes, nondermatophyte molds, and bacteria.
Results:
Approximately 50% of suspicious toenails contained both fungi and bacteria, with the dermatophyte Trichophyton rubrum contributing the highest relative abundance and presence in 40% of these samples. Of the remaining 50% of samples, 34% had bacterial species present and 16% had neither. Fungi only were present in less than 1% of samples. Nondermatophyte molds contributed to 11.0% of occurrences in fungus-positive samples. All of the control samples were negative for fungi, with commensal bacterial species composing most of the flora population.
Conclusions:
Molecular methods were successful in efficiently quantifying microbial and mycologic presence in the nail. Contributions from dermatophytes were lower than expected, whereas the opposite was true for nondermatophyte molds. The clinical significance of these results is currently unknown.
Background
Onychomycosis is the most common infectious nail disorder. Direct mycologic examination is still the cornerstone of diagnosis; however, it may take several weeks to obtain a result. Recently some dermoscopic patterns that can be useful in the diagnosis of onychomycosis were described. However, published data on dermoscopic features of onychomycosis are still limited.
Methods
We performed a prospective dermoscopic study of patients with positive fungal culture between April and December 2016. Patients with a final diagnosis of psoriasis or lichen planus were excluded from the study. Dermoscopy (polarized and nonpolarized) was performed.
Results
Thirty-seven patients were enrolled, 24 women and 13 men (median ± SD age, 48.6 ± 16.1 years). Nail samples were culture positive for Trichophyton rubrum (89.2%), Trichophyton interdigitale (8.1%), and Candida albicans (2.7%). Distal and lateral subungual onychomycosis was the most frequent clinical subtype (59.5%). The most frequent dermoscopic features were subungual keratosis (73.0%), distal subungual longitudinal striae (70.3%), spikes of the proximal margin of an onycholytic area (59.5%), transverse superficial leukonychia (29.7%), and linear hemorrhage (13.5%). Brown chromonychia was most frequently seen with nonpolarized dermoscopy (66.6% versus 24%; P = .027).
Conclusions
Specific dermoscopic signs of onychomycosis are mostly related to the proximal invasion of the nail plate. Detection of these signs is simple and can, in some cases, help avoid mycologic testing.
Diagnosis and Management of Onychomycosis
Perspectives from a Joint Podiatric Medicine–Dermatology Roundtable
Onychomycosis is a fungal infection, and, as such, one of the goals of treatment should be eradication of the infective agent. Despite this, in contrast to dermatologists, many podiatric physicians do not include antifungals in their onychomycosis treatment plans. Before initiating treatment, confirmation of mycologic status via laboratory testing (eg, microscopy with potassium hydroxide preparation, histopathology with periodic acid–Schiff staining, fungal culture, and polymerase chain reaction) is important; however, more podiatric physicians rely solely on clinical signs than do dermatologists. These dissimilarities may be due, in part, to differences between specialties in training, reimbursement patterns, or practice orientation, and to explore these differences further, a joint podiatric medicine–dermatology roundtable was convened. In addition, treatment options have been limited owing to safety concerns with available oral antifungals and relatively low efficacy with previously available topical treatments. Recently approved topical treatments—efinaconzole and tavaborole—offer additional options for patients with mild-to-moderate disease. Debridement alone has no effect on mycologic status, and it is recommended that it be used in combination with an oral or topical antifungal. There is little to no clinical evidence to support the use of lasers or over-the-counter treatments for onychomycosis. After a patient has achieved cure (absence of clinical signs or absence of fungus with minimal clinical signs), lifestyle and hygiene measures, prophylactic/maintenance treatment, and proactive treatment for tinea pedis, including in family members, may help maintain this status.
Evaluating Costs for Onychomycosis Treatments
A Practitioner’s Perspective
Onychomycosis is a common problem. The desired outcome of treatment for patients and clinicians is complete cure (negative culture and negative potassium hydroxide examination results plus a completely normal nail). This cost analysis sought to determine the cost-effectiveness of treatments for onychomycosis using complete cure as a unit of effectiveness. A simplified cost-effectiveness analysis was conducted using complete cure rates from randomized, blinded clinical trials involving at least 50 participants. Trials were identified by searching the literature, manually searching for review articles, and reviewing medication package inserts. For each trial that met the entry criteria, three levels of cost were used to calculate medication cost per complete cure: commercial price, average wholesale price, and Veterans Affairs pharmacy price. In addition, a computerized economic model was used to determine total cost per complete cure, including all medical costs. The most cost-effective treatments were those that involved terbinafine: pulse, continuous, or in combination with other agents. Itraconazole, griseofulvin, and fluconazole were less cost-effective. Ciclopirox nail lacquer was at least three times more expensive than all other agents when evaluating total costs per complete cure. Overall, the lowest cost per complete cure resulted from terbinafine treatment, with most evidence supporting 3 months of continuous therapy. (J Am Podiatr Med Assoc 96(1): 38–52, 2006)
Laser systems are a new treatment area for onychomycosis. As of January 2012, the US Food and Drug Administration (FDA) has approved four laser systems for the “temporary increase of clear nail in onychomycosis.” The FDA has approved these devices on the basis of “substantial equivalence” to predicate devices with similar technical specifications and applications. Laser therapy appears to be a promising alternative to traditional pharmacotherapy, but these systems have been tested in only limited clinical trials; therefore, it is not possible to compare their efficacy to the oral and topical drugs currently used in the treatment of onychomycosis. (J Am Podiatr Med Assoc 102 (5): 428-430, 2012)
