Scalp ringworm explained
by Dr. Andrew Forde
Tinea Capitis is the name given to a scalp infection, caused by a Dermatophyte fungus, which is common in school children but less frequently seen in adults. After puberty the glandular secretions of the scalp contain saturated fatty acids, which are hostile to the fungus. Some types of hair oils used by adults are also inhibitory.
The fungi invade either the inner or outer part of the hair shaft and can be of animal origin (zoophilic) or human origin (anthropophilic). Zoophilic infections usually originate from an infected kitten or puppy and rarely from horses, pigs and cattle. Human transmission is via the sharing of combs, brushes, hats, pillowcases and cloth chairs.
This condition presents in various ways. The earliest signs are scaly patches on the scalp, which are followed by discrete oval areas of hair loss (alopecia) or a confluent moth eaten appearance. Sometimes black dots representing broken hair may be seen in the bald areas. The inflammatory usually zoophilic forms appear as a mass of inflamed pustules around hair follicles or an abscess called Kerion. When yellow crusts with matted hair is formed, this is referred to as Favus.
Inflammatory Tinea Capitis is often associated with a mousy odour and swollen lymph nodes at the sides and the back of the neck. Permanent hair loss can result if left untreated.
Oral antifungal agents taken daily for 6-8 weeks are required to treat this infection. Griseofulvin is an old and effective treatment but sometimes other medications like terbinafine, itraconazole and fluconazole may also be used.
Shampoo containing coal tar, ketaconazole, selenium sulfide or zinc pyrithione are used to reduce the probability of spread and for hygienic purposes. The hair should be washed 2-3 times per week if possible.
Children with the infection are not required to leave school if treatment is used as directed. Most children are not contagious when using the oral medication and shampoo.
*Dr Andrew Forde is a dermatologist.