Owing to the high recurrence rate of fungal nail infections, pharmacy professionals should be able to advise patients on effective treatment and preventative and appropriate self-care strategies to avoid re-infection.
. An increased incidence among older people may be attributed to multiple factors, including reduced peripheral circulation, diabetes, inactivity, relative immunosuppression, and reduced nail growth and quality
This article will cover the causes, types and treatment of OM, practical information to help guide patient consultations and when to refer to podiatry.
Management Of Fungal Nail Infections
Figure 1 shows the composition of the nail, including the nail plate (the visible part of the nail), nail bed (the skin under the nail) and nail matrix.
The nail plate and nail bed are joined by layers of hard, translucent, keratinised cells. The nail bed and nail matrix are vascular components of the nail, with nail cells located within the nail matrix where the nail plate is formed. The thickness of the nail plate determines the length of the matrix [7], [8] .
Damage to the nail structure can affect nail growth, shape, size and, consequently, predispose the nail to infection. OM can invade any part of the nail but typically enters the nail’s free edge, sulci or damaged cuticles (see Figure 2).
Fungal Nail Infections And Toenail Fungus
Where OM infects the area underneath the nail plate, the infection produces a thick hyperkeratotic nodule that contains clusters of branching filaments (hyphae) called dermatophytoma (see Photoguide: A)
. The abnormal thickness of the nail may lead to soft tissue breakdown and/or infection resulting in inflamed subcutaneous tissue (cellulitis), ulceration in the nail bed (subungual ulceration) and/or bone infection (osteomyelitis)
The most common type of OM is distal lateral subungual onychomycosis (DLSO)(see Photoguide: B). It is characterised by build-up of soft yellow keratin between the nail plate and nail bed (subungual hyperkeratosis), detachment of the nail from the nail bed (onychosis) and skin infection around the nail (paronychia). DLSO spreads proximally to the nail matrix
Fungal Nail Infections
Cases of white superficial onychomycosis (see Photoguide: C) are characterised by distinct white ‘islands’ on the nail surface, which gradually spread to the entire nail, causing it to become soft and crumbly
White milky patches without subungual hyperkeratosis (build of keratin underneath the nail) indicateendonyx onychomycosis (EO) (see Photoguide: D). Pitting is involved with splitting of the nails. EO usually affects fingernails
Affecting fingernails and toenails, proximal subungual onychomycosis (PSO)(see Photoguide: E) is frequently found in, but not unique to, patients with HIV. The fungal infection begins at the cuticle and the nail fold before penetrating the nail plate. PSO is characterised by white discoloration that usually includes paronychia with some discharge
Paronychia: Causes And Treatment Of An Infected Nail
The most advanced type of OMis total dystrophic onychomycosis (see Photoguide: F), which invades the nail plate, nail bed and nail matrix causing severe nail dystrophy. There can be chronic swelling at the distal phalanx with the affected nail appearing thickened, yellow-brown in colour and severely deformed
Despite OM having distinct clinical features, around half of nail dystrophy cases are caused by fungal infection and, therefore, clinical examination alone is rarely sufficient to diagnose OM
Characteristics are shared with other nail diseases, such as psoriasis, lichen planus or bacterial infections (see Table 1). In addition to examining the nail(s) affected, pharmacists should ask the patient the following questions to help establish a diagnosis
Understanding And Diagnosing Nail Infections
Ideally, OM should be confirmed by direct microscopy and cultures to eliminate non-infective differential diagnosis, to identify mixed infections and to detect resistant OM
The British Association of Dermatologists (BAD) supports laboratory investigation prior to commencing oral treatment, which is in support of guidance from Public Health England (PHE)
. Guidance for use of topical medications for DLSO is less clear and although investigations would present good practice, these treatments have minimal associated risks compared with oral treatment. However, incomplete sample collection could have a major impact on false negatives. Time constraints and continuity in working patterns should be considered as culture and microscopy results may take 2–6 weeks to come back.
Fungal Nail Infections ( Oncyhomycosis ) Causes,diagnosis And Treatment A4medicine
Proximal nail bed whiteness and distal nail bed red/pink/brown discolouration (called half and half nails); absent lunula and tiny blood clots under the nail (splinter haemorrhages)
On examination, pharmacists should consider the following factors and patient groups and it may be necessary to refer the patient to a podiatrist or their GP:
The management of OM depends on the type, extent and severity of nail involvement, symptoms and pre-existing conditions. The aim of treatment is to eradicate the pathogen, restore the nail and prevent re-infection. OM is challenging to treat and affected nails may never return to normal as the infection may have caused permanent damage.
Caring For Your Child's Feet
The compact and hard nature of the nail anatomy means topical drug penetration can be poor, with the concentration reducing by 1, 000 times from the outer to inner areas
The only topical nail lacquer available in the UK for over-the-counter (OTC) purchase is amorolfine. It is licensed for mild (not more than two nails affected) DLSO and patients aged 18 years or over. Amorolfine is a broad-spectrum synthetic fungicidal with high activity against dermatophytes, as well as other fungi, yeasts and moulds. It is available as a 5% lacquer that should be applied once or twice per week
Before application, patients should be advised to file down the affected nail surfaces using a single-use nail file, clean the nail surface with the supplied swab and dry the nail surface
Fungal Culture Exeter Clinical Laboratory International
. Patients should be reminded that this process should be repeated for sequential treatments; a step that is commonly missed out. Sterile cotton buds should be used to apply the lacquer to avoid contamination.
Amorolfine maintains clinical efficacy in the nail for 14 days after treatment; however, twice-weekly application results in better outcomes compared with once-weekly application (71% versus 76% mycological cure)
. Compliance is essential; pharmacists should encourage patients to continue the treatment, given the prolonged treatment duration of 6–12 months. Side effects are rare and limited to nail disorders (e.g. discolouration, and broken and brittle nails), which may be related to OM itself.
Foot & Ankle Pain
. Tioconazole is an imidazole derivative with a broad spectrum of action against dermatophyte and yeast-like fungal species. It is available as a 283mg/mL medicated nail lacquer and is applied to affected nails twice a day. Treatment duration ranges from 6–12 months depending on the pathogen, the severity and the location of the infection. Common side effects include mild and transient local irritation that usually presents during the first week of treatment
For adults with confirmed OM, systemic therapy is advised when self-care strategies with or without topical therapy are unsuccessful or inappropriate. A recent Cochrane systematic review of oral antifungal treatments for toenail OM in more than 10, 000 patients found high-quality evidence indicating that terbinafine and azoles were effective treatments for mycological and clinical cure compared with placebo
Terbinafine and itraconazole are considered the mainstay of oral therapy for OM, although terbinafine is generally preferred over itraconazole owing to better cure rates compared with azole in toenail OM
Treatment With Loceryl
200mg once daily for 3 months, then 200mg twice daily for 7 days, repeated at 21 days. Fingers require two courses, toes require three courses and persistent infections require an additional course of treatment
Abdominal pain, agitation, confusion, depression, diarrhoea, dizziness, dyspepsia, fatigue, glossitis, hepatotoxicity, impaired hearing, kidney failure, leucopenia, menstrual disturbances, nausea, peripheral neuropathy, photosensitivity, rash, sleep disturbances, systemic lupus erythematosus, taste disturbances, vomiting
Topical and systematic combination therapy may provide synergistic antimicrobial activity. The BAD recommends this for patients who have responded poorly to topical treatment alone
How To Treat Fungal Nail Effectively
. Amorolfine 5% nail lacquer with systemic antifungals has been supported by a meta-analysis and systematic review to provide a higher percentage of total OM clearance compared with monotherapy of systemic terbinafine, without an increase in adverse effects
Photodynamic therapy combines light irradiation and a photosensitising drug to cause destruction of selected cells. Laser therapies, such as neodymiumyttrium-aluminum-garnet and low-level laser, are aimed to selectively inhibit fungal growth
. These alternative therapies may be appropriate because they are selective to local infection and avoid systemic side effects; however, robust data are scarce
Warts And Verrucas: Causes And Treatments
According to the National Institute for Health and Care Excellence (NICE), patients require advice around foot care in order to avoid and minimise exposure to situations that predispose individuals to OM (e.g. prolonged exposure to damp conditions, occlusive footwear, prevention of damaged nails and to ensure meticulous hygiene of the affected foot)
Treatment must include a combination of proper hygiene and foot care as the risk of reinfection is high. Self-care to prevent infection should be stringently practiced until the fungus is eradicated, which may take up to 18 months
Pharmacists should advise patients on nail care, washing and drying feet daily, using the correct footwear and encouraging the use of antifungal powder to help keep shoes pathogen free. See Box for important self-care messages.
Journal Of Prescribing Practice
Before initiating topical or oral therapy, patients should ideally be referred to a podiatrist for nail trimming and debridement. This assists with removing as much fungus as possible and improves topical drug penetration. Debridement alone cannot be recommended for the treatment of OM; patients using a combination of debridement and topical nail lacquer have shown a significant improvement in mycological cure compared with debridement only
. Patients with nail trauma owing to footwear, dystrophic toenails affecting
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