Nail fungal infections
Superficial fungal infestations may
affect the skin and nails.
Fungal
infections may occur all over the body.
Some
people are more susceptible to fungal infections than others.
Some
people may be carriers of fungi, but are symptom free.
If
left untreated, fungal infections may cause discomfort and pain.
Fungi
may be present on the skin without causing an infection.
Description
Superficial fungal infestations occur as infections of the skin and
nails. They are caused by fungi that are everywhere around us. Fungi thrive in
warm, moist conditions.
Fungal
infection of the nails, tinea unguium, affects toenails more often than
fingernails because toenails provide an ideal environment for fungal growth –
warm, moist conditions. Toenails also grow more slowly, giving the fungal
infection time to develop. When a fungus invades a fingernail or toenail, the
nail (nail plate) as well as the skin under the nail (nail bed) is affected.
Fungi
can be passed on quite easily from one person to another, but this does not mean
that the fungus will necessarily infect the other person. Some people are more
susceptible to fungal infections. In these people the presence of fungi on the
body will result in fungal infections.
Fungi
can live on people, objects or animals for several months.
Cause
Toenails in particular offer fungi warm, moist conditions. Athlete’s
foot refers to fungal infection between the toes. The skin is red, scaly and
macerated (white due to moisture).
Three
types of fungi are responsible for fungal nail infections:
Dermatophytes
(mostly toenails)
Yeast
– grows in areas of warm, moist skin, such as skin folds, and on the fingernails
Moulds or non-dermatophytes – on the
skin and nails (these organisms commonly grow in soil)
Toenails
injured by too much trimming or by ingrowing may become infected with fungi. A
person whose feet perspire excessively runs a greater risk of fungal infection
of the toenail. The possibility of fungal infection is greater if you wear socks
or stockings made of synthetic fibres, or shoes with rubber instead of leather
soles, or if you walk barefoot around swimming pools, showers and locker rooms.
Fungal
infections of the fingernails may result from overexposure to water and
detergents. The moisture that gets trapped under the nails encourages fungal
growth.
Nails
that are continually exposed to a warm, moist environment may develop a fungal
infection on the nail or under its outer edge (onychomycosis). When the nail
becomes separated from the skin underneath it, the condition is called
onycholysis.
Symptoms
Symptoms may include the following:
A distinct white or yellow spot on the
nail that gradually spreads over the entire nail
Discoloured,
damaged, splitting, brittle, thickened and rough nails
Cracking of nails
Build-up of debris (nail fragments and
pieces of skin) under the nail
Red, itchy or swollen surrounding skin
Athlete’s
foot occurring simultaneously
If the skin under the nail is infected (distal subungual
onychomycosis), the following symptoms may appear:
Yellow streaks in the nail bed and on
the under side of the nail (nail plate)
Build-up of debris (nail fragments and
pieces of skin) under the nail
Discolouration of the entire nail and
separation of the nail from the nail bed (onycholysis) – severe infections
Brittle and broken nails
If the nail surface is infected (white superficial onychomycosis),
there may be:
White spots or white streaks on the
nail surface
A soft and powdery nail surface
Damage
to the nail, crumbling and brown or grey discolouration
With Candida onychomycosis, the symptoms vary. This infection usually
occurs in the fingernails. The following symptoms may appear:
Opaque, greenish or brownish nails
Oddly shaped nails
Thick nails
Infection
of the nail fold skin may cause pain
Infection of all nails
Pain (the only type of fungal nail
infection that may be painful)
If the base of the nail is infected (proximal subungual onychomycosis),
the following symptoms may appear:
Whitish appearance of the nail base
Opaque nails
Prevalence
Only about 50% of all nail diseases and disorders are due to fungal
infection. More adults than children get fungal nail infections. Of all fungal
nail infections, about 80% are of the big toenail and 20% of the fingernails.
Men get infections caused by dermatophytes more often than women do, and women
get yeast infections more often than men do. Moulds are more prevalent in humid,
tropical climates and dermatophytes more in mild climates.
Course
Untreated nail infections can lead to unsightly and painful nails and
fingers. If left untreated, fungal nail infections may become worse, other parts
of the nails and/or other nails may become infected and the skin around the nail
becomes infected. Nails may become odd in shape and appearance, even after
treatment.
Some
fungal nail infections progress very slowly, but others develop rapidly,
especially in warm and damp conditions.
Risk
factors
As people get older, their nails
thicken and grow more slowly, making them more susceptible to infection.
A person whose feet perspire
excessively is at greater risk of getting toenail infections.
The likelihood of infections increases
if one wears socks or stockings made of synthetic fibres; tight, ill-fitting
shoes; shoes with rubber instead of leather soles; or if one walks barefoot
around swimming pools, showers and locker rooms.
Poor
blood circulation due to disease may increase the risk of infection.
When to
see a doctor
Call your doctor if:
A
nail is severely discoloured, damaged or thickened
There
is a build-up of pieces of skin and nail fragments under the nail
There
are signs of a bacterial infection such as increased pain, swelling, redness,
tenderness and heat; red streaks extending from the area; a discharge of pus;
and a fever with no other identifiable cause
The infection is spreading
The condition is painful
Diagnosis
Fungal nail infections are diagnosed on the basis of a medical
history, a test of a sample of the debris under the nail, or a nail sample
scraped or cut from the nail.
A
KOH (potassium hydroxide) preparation can determine if a fungus is causing the
condition. This test is done in a clinic or a doctor’s surgery.
A fungal culture may be done to
determine if a fungus is causing the condition and which fungus may be the
cause.
Rarely,
the doctor may take a skin biopsy for a microscopic study.
Treatment
Home treatment
Home treatment of fungal infections focuses on preventing reinfection
and spreading of the infection.
Medication
For fungal toenail infection, griseofulvin is used to prevent the
fungus from spreading while the new toenail grows out, a process that can take
at least a year. This medication does not kill the fungus.
Griseofulvin is seldom used for treatment of nail infection. More potent oral
medications are now available. These medications are absorbed into a person’s
blood at levels that can penetrate a nail and destroy the fungus. Treatment
usually lasts for 6-12 weeks. These medications are itraconazole, terbinafine
and fluconazole. The first two can treat a wide range of fungal infections,
while fluconazole works best for one specific type of fungus.
An
anti-fungal cream may be prescribed to confine the infection.
Surgery
In the case of fungal nail infections, removal of the nail may be
indicated if the infection is severe and painful or if oral anti-fungal
medication would interfere with other medication you may be taking, for example
blood thinners, seizure medication and some allergy medication. In the case of
recurrent infections, the nail root may be removed permanently. Surgery should
only be used as a last resort.
Prevention
Keep
the nails clean and dry. Dry the feet well after a bath or shower, especially
between the toes.
Change socks at least daily, or more
often if your feet perspire excessively.
Do
not over-trim nails, or pick at and poke around the toenails; prevent minor
injury which might provide an entry point for fungi.
Do not wear tight or ill-fitting
shoes.
Try not to wear the same pair of shoes
for two days in a row. Give a pair of shoes time to dry out.
Do
not share shoes with someone else.
Do not walk barefoot in public or
shared showers or locker rooms. Wear shower sandals or shower shoes.
Treat other infections such as
athlete’s foot.
