Definition
Tinea versicolor is a fungal infection of the skin caused by the fungus Pitysporum orbiculare. It results in patches of skin lesions, ranging from white to pale brown. It will recur frequently in susceptible individuals.
Who gets it?
This fungal skin infection is common in young people. It is often only noticed in the summer because the white spots do not tan, leaving a speckled appearance on the skin. It is probably precipitated by sweating but is not a marker for poor hygiene.
There are no predisposing factors and no specific risk factors for the infection.
Symptoms and signs
The lesions vary from pale brown, to brown to white. They tend to coalesce and are slightly scaly with a well-circumscribed edge. They are most common on the chest, neck and abdomen and are sometimes seen on the face.
They are not itchy unless the person is very hot – which can lead to itching at night.
Diagnosis
The clinical appearance of the lesions is characteristic and is the usual way in which a diagnosis is made.
Skin scrapings will show fungal hyphae – fine hair-like projections – and spores if examined under the microscope.
A special light for examining the skin called Wood’s light will show golden fluorescence in affected areas of skin and so can show the extent of the infection.
Treatment
There are many skin lotions which can clear tinea versicolor.
The most commonly used are:
- Selenium sulphide
- The imidazole anti-fungals
- Zinc pyrithione
- Sulphur-salicylic acid combinations
- Topical terbinafine
Selenium sulphide in shampoo form (Selsun shampoo®) can be applied undiluted to the skin to all involved areas including the scalp, for three or four days. It is usually put on at bedtime and then washed off in the morning.
This can cause irritation in some people and in this case can be washed off after 20 to 60 minutes or stopped for a few days. Some people complain that this causes burning.
When chronic or recurring, systemic imidazol drugs in low intermittent doses may be used.
Outcome
The lesions may remain pale even after the fungus is cleared until there is some sun-exposure again.
The condition tends to recur since the fungus is a normal skin inhabitant. The scalp may be the source of the fungus and it can spread from there.
When to see the doctor
Any skin changes should be seen by your doctor since diagnosis is often difficult. When chronic or recurring, the advice of its ongoing topical and systemic management should be sought.
(Reviewed by Dr D. Presbury)