Cradle cap is a condition that causes scaly patches on a baby’s scalp. It is a common name for infantile seborrheic dermatitis and is also known as milk crust or honeycomb disease. It can cause thick crusts and scales which could be white or yellow.
The most common presenting sign is thick crusts or patchy scales on the scalp. Other signs are skin flakes, oily skin covered with flaky white scales, scales could also be yellow. There is also a possibility if mild redness. There could be similar lesions on the ears, eyelids, groin, armpits and nose. It generally does not irritate the baby or cause pruritus. It there are suspicions of prurits then another skin condition should be considered .
Diagnosis of cradle cap is based solely on the history and physical findings. Laboratory, imaging or histological evaluation are of no added value.
There is no treatment for cradle cap as it is self-limiting and disappears on its own, whether it is caused by hormones or yeast. However, if the parents of the babies have cosmetic concerns, the following options may be considered. Gentle washing of the scalp is the commonest prescribed home remedy. The scales are then combed out gently and brushed off with a soft brush or cloth. This has to be done gently to avoid worsening the condition or causing baldness. Also, applying petroleum jelly and leaving it overnight is another popular home remedy. The scales readily fall off during the night and the remaining brushed off in the morning. Making a paste from sodium bicarbonate and applying in in the affected place for about 10 minutes can help to lift the scales. These are home remedies with no research data to back them up .
The use of shampoos remain controversial.
Mild baby shampoo is recommended by some sources for washing the infant hair. Dandruff shampoos that contain salicylic acid aren’t recommended as the active ingredient could be absorbed through the skin of the baby.
If the symptoms show no sign of abating after these home remedies, ketoconazole shampoos and creams may be useful. Ketoconazole has been shown to have a high level of efficacy in the treatment of moderate to severe forms of this condition and it is not absorbed through the skin. The corticosteroid hydrocortisone cream is useful in reducing redness and inflammation .
If the lesion is on the eyelid. The eye should be cleansed by a cotton swab soaked in well diluted baby shampoo.
This condition often clears as a baby grows older. It however, on rare occasions, persists into toddler years and even early childhood.
The cause of seborrheic dermatitis still remains largely unknown. Although it has been speculated that around the time of birth, some unidentified hormones are passed from mother to baby. These hormones then cause an abnormal stimulation of the oil producing glands (seborrheic glands) and hair follicles leading to increased production of oil (sebum) . Another speculated cause is the yeast Malassezia. Malassezia is a fungus that grows in the sebum produced by the seborrheic glands.
It is generally a disease of infancy and it occurs between the ages of 3 weeks and 12 months. The peak prevalence age is 3 months as 70% of cases are seen in infants of that age. The prevalence decreases steadily afterwards. There has however been some reported cases in children over 1 year with as much as 7% of cases occurring in children between the ages of 1 and 2 years. It is common in all races and equally distributed between sexes .
In the same vein as the cause, the pathophysiology is not known. It is believed that there is transplancental migration of maternal androgens to the fetus. This androgens then stimulate the infant’s sebaceous glands. This stimulation even though seemingly insufficient to cause cradle cap, is necessary for its development.
A yeast fungus, Malassezia, has also been implicated although its role is unclear. Malassezia is a lipid dependent yeast whose colonization has been reported in infants with cradle cap. This fungus however has also been reported in other dermatological conditions and in normal infants.
Daily shampooing of the baby’s hair with mild baby shampoo can help prevent the development of this condition .
Cradle cap is a harmless condition and it is usually self-limiting with most cases resolving within 12 months. Some children may have it for longer necessitating a medical visit. Although it is called cradle cap, similar lesions may appear on the baby’s armpits, eyebrows or eyelids .