Various germs such as fungi and bacteria live harmlessly
on the skin and inside the body. However certain types of fungus, or
overgrowths of normally harmless types can cause the symptoms of a fungal
infection of the skin.
Most fungal skin conditions are not serious and are
usually not easily spread from person to person. Infections deeper in the
body can be more serious.
Symptoms of fungal infections
The symptoms and appearances of a fungal skin infection
depend on the type of fungus causing it and the part of the body affected.
The rash may have a variety of appearances. Some are red, scaly and itchy,
whereas others can produce a fine scale similar to dry skin. The site of
infection may be just one area of the body, or there may be several
infected areas. Fungal rashes can sometimes be confused with other skin
Types of fungal skin infections
Fungal infections usually affect the skin because they
live off keratin, a protein that makes up skin, hair and nails.
Fungal skin infections are divided into groups depending
on what type of organism is involved. The full name depends on the location
of the infection on the body.
The most common fungal infections are listed below.
This is called "jock itch" because it occurs
in sportspeople. It causes an itchy, red rash in the groin and surrounding
area and is commonly seen in men who have been sweating a lot. Often the
man also has athlete's foot, and scratching the feet followed by the groin
may spread the infection.
the body (tinea corporis)
This affects the body, often in exposed areas and causes
red patches, which are scaly at the edge with clear skin at the centre. The
patches spread out from the centre. It can be caught from domestic animals.
Ringworm of the scalp tends to affects young children and can cause hair
loss with inflammation in the affected area.
This condition causes increased dark patches on pale or
untanned skin and light patches on tanned or darker skin. Another name for
this condition is tinea versicolor. People with oily skin are most likely
to be affected.
Causes of fungal infections
A number of situations make it more likely that a fungal
infectin will develop. People are more at risk of fungal infections if they
immune system weakened by cancer or HIV infection
Moist skin encourages fungal infections. This means
fungal infections are more likely when skin is not dried properly after
sweating heavily or bathing, or when it is covered with a material that
does not allow sweat to evaporate. Damage to the skin surface, such as a
cut or graze, can also encourage fungi to grow.
Fungal infections inside the body can cause more serious
health problems than those on the skin. These infections only affect people
whose immune systems are not working properly as a result of another
illness or treatments for cancer.
Sometimes fungal infections are easy for doctors to
diagnose from the appearance and location of the rash, e.g. athlete's foot.
If the doctor wants to make sure what is causing the symptoms, he or she
may take a scraping of skin or a fragment of nail or hair and send it to
the laboratory for analysis before choosing the treatment.
Since most skin fungal infections are surface
infections, they are usually anti-fungal treatments applied directly to the
infected area (topical treatments).
There are a variety of treatments available in the form
of creams, lotions and medicated powders. If the rash covers quite a large
area of skin, or affects nails or hair, then tablets may be required.
Some treatments are available over the counter from a
pharmacist, without a prescription. Examples include clotrimazole,
miconazole and terbinafine. Pharmacy own-brands are also available for some
of these products. Ask your pharmacist for advice.
Stronger forms of topical treatments and antifungals in
tablet form are only available on prescription. For example, ketoconazole
shampoo (e.g. Nizoral) may be prescribed for fungal scalp infections, and
terbinafine tablets may be prescribed for fungal nail infections.
These treatments are usually effective and only
occasionally cause side effects. These may include skin irritation and
allergic reactions. It is not unusual for the rash to return, even when it
seems to have been treated. The treatment may need to be used for at least
four weeks to prevent the rash from coming back.
Anyone buying over-the-counter treatments needs to be
sure that it is a fungal infection that they have. They may recognise a
rash that has been previously diagnosed as fungal. If there is any doubt
about the diagnosis, or if over-the-counter treatments do not work, then
you should seek advice from your GP.
Helping prevent fungal infections
Taking these steps may help to reduce the risk of
getting a fungal infection:
the skin carefully after bathing
loose fitting clothes and underwear
sharing towels, hairbrushes, and combs, which could contain skin
fragments that harbour fungal colonies
socks or tights daily
fabrics that allow the skin to "breathe" - natural fibres
such as cotton are better than nylon or polyester for underwear
sportspeople, synthetic fibres that "wick" the sweat away
from the body, helping to keep the skin dry, may be preferable
with diabetes need to keep good control of their blood sugar