Onychomycosis accounts for 50% of all nail disease cases and is commonly caused by dermatophytes. Diabetes, human immunodeficiency virus, immunosuppression, obesity, smoking, and advancing age are ...predisposing factors of this fungal infection. Potassium hydroxide and culture are considered the current standard for diagnosing onychomycosis, revealing both fungal viability and species identification. Other diagnostic tests currently available include periodic acid–Schiff staining, polymerase chain reaction techniques, and fluorescent staining. Across 6 recently published epidemiology studies, the global prevalence of onychomycosis was estimated to be 5.5%, falling within the range of previously reported estimates (2%-8%). Newly approved onychomycosis treatments include efinaconazole, tavaborole, and laser therapy with lasers only approved to temporarily increase the amount of clear nail. Additional onychomycosis treatments being investigated include iontophoresis and photodynamic therapy with small open-label studies reported thus far. Preventative strategies, to help decrease recurrence and reinfection rates, include sanitisation of footwear and prophylactic topical antifungal agents.
Onychomycosis: a review Gupta, A.K.; Stec, N.; Summerbell, R.C. ...
Journal of the European Academy of Dermatology and Venereology,
September 2020, 2020-Sep, 2020-09-00, Letnik:
34, Številka:
9
Journal Article
Recenzirano
Onychomycosis is a fungal infection of the nail, causing discoloration and thickening of the affected nail plate, and is the most common nail infection worldwide. Onychomycosis was initially thought ...to be predominantly caused by dermatophytes; however, new research has revealed that mixed infections and those caused by non‐dermatophyte moulds (NDMs) are more prevalent than previously thought, especially in warmer climates. Microscopy and fungal culture are the gold standard techniques for onychomycosis diagnosis, but high false‐negative rates have pushed for more accurate methods, such as histology and PCR. As NDMs are skin and laboratory contaminants, their presence as an infectious agent requires multiple confirmations and repeated sampling. There are several treatment options available, including oral antifungals, topicals and devices. Oral antifungals have higher cure rates and shorter treatment periods than topical treatments, but have adverse side effects such as hepatotoxicity and drug interactions. Terbinafine, itraconazole and fluconazole are most commonly used, with new oral antifungals such as fosravuconazole being evaluated. Topical treatments, such as efinaconazole, tavaborole, ciclopirox and amorolfine have less serious side effects, but also have generally lower cure rates and much longer treatment regimens. New topical formulations are being investigated as faster‐acting alternatives to the currently available topical treatments. Devices such as lasers have shown promise in improving the cosmetic appearance of the nail, but due to a high variation of study methods and definitions of cure, their effectiveness for onychomycosis has yet to be sufficiently proven. Recurrence rates for onychomycosis are high; once infected, patients should seek medical treatment as soon as possible and sanitize their shoes and socks. Prophylactic application of topicals and avoiding walking barefoot in public places may help prevent recurrence.
Summary
The topical treatment of nail fungal infections has been a focal point of nail research in the past few decades as it offers a much safer and focused alternative to conventional oral therapy. ...Although the current focus remains on exploring the ways of enhancing permeation through the formidable nail barrier, the understanding of the nail microstructure and composition is far from complete. This article reviews our current understanding of the nail microstructure, composition and diseases. A few of the parameters affecting the nail permeability and potential causes of the recurrence of fungal nail infection are also discussed.
Onychomycosis continues to be the most challenging disease condition for pharmaceutical scientists to develop an effective drug delivery system. Treatment challenges lie in incomplete cure and high ...relapse rate. Present compilation provides cumulative information on pathophysiology, diagnostic techniques, and conventional treatment strategies to manage onychomycosis. Novel technologies developed for successful delivery of antifungal molecules are also discussed in brief. Multidirectional information offered by this article also unlocks the panoramic view of leading patented technologies and clinical trials. The obtained clinical landscape recommends the use of advanced technology driven approaches, as a promising way-out for treatment of onychomycosis. Collectively, present review warrants the application of novel technologies for the successful management of onychomycosis. This review will assist readers to envision a better understanding about the technologies available for combating onychomycosis. We also trust that these contributions address and certainly will encourage the design and development of nanocarriers-based delivery vehicles for effective management of onychomycosis.
Aspergillus
spp. are emerging causative agents of non-dermatophyte mould onychomycosis (NDMO). New
Aspergillus
spp. have recently been described to cause nail infections. The following criteria are ...required to diagnose onychomycosis due to
Aspergillus
spp.: (1) positive direct microscopy and (2) repeated culture or molecular detection of
Aspergillus
spp., provided no dermatophyte was isolated. A review of 42 epidemiological studies showed that onychomycosis due to
Aspergillus
spp. varies between < 1 and 35% of all cases of onychomycosis in the general population and higher among diabetic populations accounting for up to 71% and the elderly; it is very uncommon among children and adolescence.
Aspergillus
spp. constitutes 7.7–100% of the proportion of NDMO. The toenails are involved 25 times more frequently than fingernails.
A. flavus
,
A. terreus
and
A. niger
are the most common aetiologic species; other rare and emerging species described include
A. tubingensis
,
A. sydowii
,
A. alliaceus
,
A. candidus
,
A. versicolor
,
A. unguis
,
A. persii, A. sclerotiorum, A. uvarum, A. melleus, A. tamarii
and
A. nomius
. The clinical presentation of onychomycosis due to
Aspergillus
spp. is non-specific but commonly distal–lateral pattern of onychomycosis. A negative culture with a positive KOH may point to a NDM including
Aspergillus
spp., as the causative agent of onychomycosis. Treatment consists of systemic therapy with terbinafine or itraconazole.
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