This first-time mother was rather concerned about the appearance of persistent yellow, greasy plaques on the head of her three-month-old baby. The child was completely unperturbed, with no itching or scratching in the area, and there were no other signs or rashes on other parts of the body.
The mother had first noticed the plaques when the baby was about three weeks old, but they had become progressively more obvious and caused friends to comment and suggest that she sought advice.
The diagnosis of cradle cap may be made on clinical grounds. The mother can be advised that this is a very common problem in babies, but most cases clear spontaneously within a few months; treatment is often unnecessary.
Frequent hair washing with a mild baby shampoo and the application of a baby oil to soften and loosen the scales allows for their easier removal with a soft hairbrush. However, olive oil is not advisable, because it may encourage the proliferation of the yeast Malassezia. Neither is groundnut (peanut) oil, because of the risk of allergies.
More vigorous attempts at removal run the risk of introducing infection, which would require treatment with an antibiotic. If this approach is insufficient or the rash is spreading, a medicated shampoo containing ketoconazole can be offered and in cases where inflammation is a problem, hydrocortisone cream.
The cause of cradle cap is not known, but it is thought that it may be related to overactive sebaceous glands, producing excess sebum in newborns who have been exposed to maternal transplacental androgens. Another possible factor is colonisation by Malassezia. Often the skin changes are restricted to the scalp, but sometimes they can spread to the ears, eyelids, eyebrows, nasolabial folds, nappy area and intertriginous areas.
This symptomless condition is first noticed when the child is about three weeks old, but usually clears in the first year. There is a risk of secondary infection, which is more likely to occur if attempts are made to scrape off the scales, for example with the fingernails.
- Atopic dermatitis
- Langerhans' cell histiocytosis
- Vitamin deficiency
Dr Watkins is a retired GP in Hampshire