Fungal nail infection (onychomycosis) is characterised as infection of part or all of the nail unit, which includes the nail plate, the nail bed, and the nail matrix of the hands or feet.1, 2, 3 Over time, the infection causes discoloration and distortion of part or all of the nail unit.4 The tissue under and around the nail may also thicken. Fungal nail infections can readily spread from one nail to another and from toe to finger nails. Sharing bed linen, bath mats, towels, socks and gloves can enable cross-infection to other individuals.
How common is it?
In the UK the reported incidence was 2.8% of adults in a 1992 study, however a more recent European surveys suggest the incidence is 5-25%, especially in the elderly.5 If the incidence is 10%, then there are more than 5,000,000 cases in the UK at any one time. Of these 60% are treated by GPs for 3 to 6 months without a laboratory confirmation.6 There is a 20% failure rate of the treatment.
What causes it?
T rubrum (a fungus) is now regarded as the most common cause of onychomycosis in the world.7 Several factors that increase the risk of developing a fungal nail infection have been identified. One survey found that 26% of people with diabetes had onychomycosis and that diabetes increased the risk of infection, but the type and severity of diabetes was not correlated with infection.8 Another survey found that peripheral vascular disease and a suppressed immune system increased the risk of infection. These factors may explain the general increase in prevalence of onychomycosis in the elderly population.9 Environmental exposures such as occlusive footwear or warm, damp conditions have been cited as risk factors, as has trauma.10 Fungal skin infection has been proposed as a risk factor.11, 12
What's the outcome?
Onychomycosis does not have serious consequences in otherwise healthy people. However, the Achilles Project9 (studying 846 people with fungal toenail infection) found that many people complain of discomfort in walking (51%), pain (33%), or limitation of their work or other activities (13%). Gross distortion and irregular growth of the nail may cause trauma to the adjacent skin and may lead to secondary bacterial infection. In immunocompromised people (those taking immune-suppressive drugs to stop cancer or transplanted organ rejection, those with HIV/AIDS etc.), there is a risk that the infection will spread and affect the whole body.
Treatment
There are two methods of treating onychomycosis, either a topical lacquer or an oral product with a combination used in severe and at risk patients.
People taking oral antifungal drugs report greater satisfaction and fewer onychomycoses-related problems such as embarrassment, self consciousness, and being perceived as unclean by others, compared with people using topical antifungals. Oral antifungals have general adverse effects which include gastrointestinal complaints (such as diarrhoea), rash and respiratory complaints.
The laundry of infected individuals needs to be disinfected in order to reduce the risk of re-infection and the cross-infection of people who share towels, bath mats and bed linen. Eradicil is an ideal medicated laundry pre-wash for such disinfection.
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9 Burzykowski T, Molenberghs G, Abeck D, et al. High prevalence of foot diseases in Europe: results of the Achilles Project. Mycoses 2003;46:496–505
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11 Svejgaard EL, Nilsson J. Onychomycosis in Denmark: prevalence of fungal nail infection in general practice. Mycoses 2004;47:131–135.
12 Barisic-Drusko V, Rucevic I, Biljan D, et al. Epidemiology of dermatomycosis in Eastern Croatia – today and yesterday. Coll Antropol 2003;27(suppl 1):11–17