Parents may notice a dry scalp on children of any age, from newborns to teens. Dry scalp is a common complaint with many different causes. Scabies, head lice and tinea capitis are common infectious causes of dry, scaly scalps in children as discussed below.
Tinea capitis is a fungal infection of the scalp. It is a common cause of scaly scalps in children and is actually under diagnosed. The types of fungus that infect the superficial skin of the scalp can come from other children or animals, cats in particular. Trichophyton tonsurans is the most common fungus to cause “ringworm” of the scalp.
Tinea capitis may appear as mild scaling of the scalp, similar to dandruff, or it may present with pustules (red bumps with white centers) and thick flat plaques with a red base interspersed throughout the hair follicles. In addition, some children with tinea capitis develop flaky scale with kerion which is a deep, firm raised red area with hair loss and lots of oozing.
Other findings in infants and children with tinea capitis can include small circles of hair loss, known as alopecia, with pustules and flaking skin. As well as enlarged lymph nodes at the base of the scalp on the nape of the neck. The large lymph nodes, known as posterior cervical adenopathy, are seen in patients with a significant inflammatory response to the fungal infection in their scalp.
Head lice must always be considered in a child with an itchy scalp. Head lice are very common, particularly in school-age children and often first present as pruritis (itchiness) without any visible lesions on the scalp. However, the head louse can be seen with close inspection. It is less than 2 mm and is usually located on the back of the head, behind the ears and in neck hairs.
Head lice also lay eggs that become stuck to the hair shaft at the root. Lice eggs are known as nits and will not come off of the hair shaft, a key factor to distinguish these tiny white spots from the tiny white flakes of dandruff in kids.
Some children who have had head lice for a longer period of time will have areas of broken skin or scabs on their scalp as a result of scratching. Lymph node enlargement can also occur, particularly cervical node adenopathy.
Scabies is usually seen on areas such as wrists, arm pits, breasts, belly buttons and the webs between the fingers. However, scabies can also infect the scalp in very young children and any person with a compromised immune system. Infants or toddlers with scabies of the scalp will almost always have scabies elsewhere as evidenced by raised, reddish tracks in the skin or scalp that are usually itchy. These lines are actually the burrows of the mites.
Some of these forms of dry scalp require oral medications and/or topical treatments. It is important to have a scalp problem in a baby or child quickly diagnosed by their doctor so that the condition can be treated appropriately. This can prevent complications such as hair loss, secondary bacterial infections from scratching, and spread of the scalp problem to the whole household.
Source: Approach to the Patient with a Scalp Eruption. UptoDate Online. http://www.uptodate.com.libproxy.lib.unc.edu/online/content/topic.do?topicKey=dermati/4472&selectedTitle=1~92&source=search_result