Fungal nail infection: diagnosis and managementBMJ 2014; 348 doi: https://doi.org/10.1136/bmj.g1800 (Published 24 March 2014) Cite this as: BMJ 2014;348:g1800
- Samantha Eisman, dermatologist,
- Rodney Sinclair, professor of dermatology
- 1Sinclair Dermatology, East Melbourne, Vic 3002, Australia
- Correspondence to: R Sinclair
Friable nail plate and nail spikes (yellow hyperkeratotic bands) suggest onychomycosis
Histopathology of nail clippings can be done easily and quickly and is an economical way to establish a pathogenic role of fungi; specimens can be sent without fixatives or transport medium and results are available in 3-5 days
Treatment should not be started before confirmation of infection by mycology
False negative rates for culture are 30%; therefore a negative test result cannot exclude infection and should be repeated if clinical suspicion is high
Consider non-dermatophyte moulds if onychomycosis is unresponsive to antifungals, and if microscopy provides a positive result but cultures give negative results
Onychomycosis is the term used for fungal infections of nail. A recent review of population based studies of onychomycosis in Europe and the United States found a mean prevalence of 4.3%.1 Onychomycosis can be a source of pain and discomfort and can impact on patients’ quality of life, with psychosocial and physically detrimental effects.2 Disease of the fingernails can cause impaired or lost tactile function, whereas disease of the toenails can interfere with walking, exercise, and how shoes fit. Untreated patients can act as source of infection for family members and potentially contaminate communal areas. Infection may be chronic and resistant to treatment, with 16-25% of patients not achieving cure by current treatments.3 No spontaneous clearing is known to occur. This review provides an evidence based overview of the diagnosis and management of onychmoycosis.
Sources and selection criteria
We searched Medline, PubMed, the National Institute for Health and Care Excellence website, and the Cochrane Library for systematic reviews, meta-analyses, randomised and non-randomised controlled clinical trials, and case series and reports using the search words “fungal nail disease/infection”, “tinea unguium”, and “onychomycosis”. We also consulted recent guidelines submitted for publication by the British Association of Dermatologists.
What causes onychomycosis?