Clive Anderson
RINGWORM OF the scalp is a common condition sometimes approaching epidemic proportions in some schools. It is the most common childhood fungal infection worldwide and is occurring more frequently.
This condition evokes significant dread and fear in the hearts of parents whose children have caught it. They worry that its presence on their child's head speaks to a lack of hygiene. While it is true that poorer children and children living in more crowded conditions are at greater risk, ringworm can affect all children. The disease is rare in adults although it may affect the elderly.
There are more than 40 species of fungi that commonly invade the skin and hair. Six of these represent the most common causes of tinea capitis or scalp ringworm. These fungi, called dermatophytes, may be found in soil, on humans, or on pets. They reside in the non-living cornified layer of the skin and can invade the outermost layer of the skin the stratum corneum and other structures which are made from the epidermis like the hair and nails. The fungi grow centrifugally in the outer skin layer. When the fungal branches, or hyphae, invade the keratin of the hair the shaft becomes brittle and breaks off at the surface of the scalp.
Hair care practices like the hairstyle, frequency of washing, the use of hair-conditioners and oils do not appear to play a significant role in predisposing for this disease. It is common though for ringworm of the scalp to spread through the sharing of combs, and hairbrushes. The organism remains viable on combs, brushes, couches and sheets for long periods.
The infection begins as a small red bump around a hair on the scalp. Within days the bump becomes paler and scaly. The hairs appear dry and discoloured and break off a few millimetres above the scalp. As the infection spreads, the small bumps form a typical ring shape. Itching is minimal but can occasionally be intense.
Clinically, the infection may resemble dandruff with scaling of the scalp, there may be significant hair loss giving the scalp the appearance of black dots. Occasionally, a deep abscess, called a kerion, may form. In severe cases there is the potential for scarring and permanent hair loss.
Because there is direct invasion of the skin and hair, topical treatment is usually inadequate. This is because topical application of the medicine does not result in sufficient getting to the site of the infection. Consequently, creams, lotions and shampoos are not effective treatment for ringworm of the scalp. Oral therapy is necessary for successful eradication.
Take home message :
Topical treatment is ineffective
Shampoos with selenium sulfide will reduce the risk of spread of the infection by reducing the shedding of spores
The use of topical steroids should be avoided
Although ringworm is very infectious among children, once the child is receiving adequate treatment he or she may be allowed to attend school
Haircuts, shaving of the head, wearing caps during treatment are not necessary
Do not share combs, hairbrushes or caps
Shampoo hair as soon as possible after a haircut
Asymptomatic carriers within the home are the most common mode of spread, as they do not have any signs of the infection and may act as a continuing source of infection.
Dr. Clive Anderson is a dermatologist and venereologist; email: yourhealth@gleanerjm.com.
