What is cradle cap
Cradle cap also known as pityriasis capitis, is the infantile version of seborrheic dermatitis affecting the scalp of newborns. Cradle cap is common, harmless and doesn’t usually itch or cause discomfort. Do not pick at the scales as this can cause an infection. Cradle cap is not contagious and is not caused by poor hygiene or an allergy. Cradle cap usually appears in babies in the first two months and clears up without treatment within weeks to a few months.
Seborrheic dermatitis is a common, chronic or relapsing form of eczema/dermatitis that mainly affects the sebaceous, gland-rich regions of the scalp, face, and trunk 1. Seborrheic dermatitis exhibits two incidence peaks, one during infancy, and the other during the fourth to sixth decades of life 2. The prevalence of seborrheic dermatitis ranges from 1 to 5 percent in the immunocompetent population and increases in the immunocompromised population, especially among patients with acquired immunodeficiency syndrome (AIDS) 3. Seborrheic dermatitis has also been observed in conjunction with other skin diseases, such as rosacea (rosacea-seborrheic dermatitis overlap), blepharitis, acne vulgaris, pityriasis versicolor, and Malassezia folliculitis 4. However, infantile seborrheic dermatitis (cradle cap) is distinguished from adult or adolescent seborrheic dermatitis in that the infantile form is almost always confined to the first 3 to 12 months of life, while adult seborrheic dermatitis is characteristically chronic and relapsing throughout life 5.
Cradle cap is a very common skin disorder affecting the oil-rich parts of the skin, including the face, ears, and scalp, and it is often seen in babies up to 3 months of age. The skin becomes flaky and inflamed, and a yellowish scale can accumulate. If the scale is picked off, the skin underneath will look pink or red. Cradle cap itself is not serious, but the affected areas can become infected if not treated properly. The cause of cradle cap is related to overgrowth of normal skin yeast including Malassezia (Pityrosporum) species and Candida.
Any baby can develop cradle cap. Cradle cap is not a contagious condition, nor does it occur because of poor hygiene.
Cradle cap begins as a flaky scalp; it may then progressively worsen to a yellow scale layered on pink or red skin. The hair may become matted down in the scale. Babies may be itchy and may scratch at their heads or more commonly, rub their heads or faces on surfaces. If the cradle cap becomes infected, it will ooze, scab, become increasingly red, or the baby might develop a fever.
Cradle cap treatment
Cradle cap is easily treated; start by trying to gently remove some of the scale and flakiness by giving the baby a warm bath with gentle baby shampoo. If this is not sufficient, try loosening the scale before bath time by applying a bland oil, such as mineral oil, massaging it in and carefully combing and shampooing it out at bath time. Finally, you may try a shampoo designed for dandruff in adults, such as one with salicylic acid or selenium sulfide, although you should discuss this with your baby’s doctor before attempting it if the baby is younger than 3 months. Additionally, if you do try adult dandruff shampoo on the baby, be very careful to not get any shampoo in his/her eyes.
Your baby’s doctor may recommend a stronger antifungal shampoo or an antifungal cream. If the area is infected, he/she will prescribe antibiotics. If the area is very inflamed, your doctor may prescribe a steroid cream.
What does cradle cap look like?
Classically with cradle cap, there is a non-inflammatory eruption of greasy yellow scales on the scalp. The vertex and frontal areas are most commonly affected. Cradle cap is usually not itchy and infants are otherwise generally well.
Cradle cap is easy to recognise by the large, greasy, yellow or brown scales on your baby’s scalp.
The scales flake and may make the affected skin look red. Sometimes the hair will come away with the flakes, but it will grow back.
It usually occurs on the scalp but can also affect the face, ears, neck, nappy area and armpits, and behind the knees.
Figure 1. Cradle cap baby – the baby may have anywhere from fine, white scaling to greasy, thick hyperkeratosis of the scalp.
Figure 2. Cradle cap baby – greasy, yellow scaly patches that sometimes appear on the scalps of young babies
Who gets cradle cap?
Cradle cap is extremely common with an estimated prevalence of 9.5–10%. Cradle cap is seen most commonly in infants aged between 3 weeks and 12 months with peak prevalence at 3 months of age 6. There is no gender or racial predilection.
Cradle cap causes
The cause of cradle cap is not known. It may be related to hyperactivity of sebaceous glands responsive to residual circulating maternal androgens. Malassezia (Pityrosporum) has also been implicated although its exact role is not clear 7.
The fact that cradle cap responds to antifungal medication strongly supports the role of yeast as a causal factor 8. This theory is further supported by the observed reduction in the number of Malassezia (Pityrosporum) yeast cells during treatment, which correlates with clinical improvement 9. Recurrence of the disease is observed following a rebound in the number of Malassezia yeast cells to pretreatment levels 10. Evidence from research indicates that human sebocytes (fat-producing cells) respond to androgen stimulation, and their increased activity worsens the severity of cradle cap 8.
How is cradle cap diagnosed?
Diagnosis is usually made clinically based on recognition of typical lesions on the scalp of an infant.
How to prevent cradle cap
Gentle, daily use of baby shampoo should be tried initially. If this fails or the crust is particularly thick, a vegetable or other oil overnight and a mild tar shampoo in the morning is usually effective. A soft infant brush or comb may be helpful to remove any adherent crust. Ketoconazole 2% cream is also shown to be an effective choice with a clinical cure rate of 79%. Occasionally, a mild topical steroid may be needed.
Tips to help reduce the build-up of scales on the scalp:
- regular washing of the scalp with a baby shampoo, followed by gentle brushing with a soft brush to loosen scales.
- soften the scales with baby oil first, followed by gentle brushing, and then wash off with baby shampoo.
- soak the crusts overnight with white petroleum jelly, or vegetable or olive oil, and shampoo in the morning.
You can buy special shampoo for cradle cap from a pharmacy. Always read the instruction leaflet to check it’s safe to use on your child.
Avoid getting the shampoo in your baby’s eyes. If you’re unsure about using it, speak to a pharmacist for advice.
If these methods don’t work, speak to your pharmacist about using a greasy emollient or soap substitute, such as emulsifying ointment.
There is usually no need to see your doctor if your baby has cradle cap. However, you may want to ask them for advice if there is swelling to the scalp or if the cradle cap spreads to other parts of the body.
How to treat cradle cap
The initial approach, especially in mild and localized disease, should be conservative, involving either application of gentle emollient or repeated shampooing, followed by careful removal of scales using a soft toothbrush or comb.
More extensive or resistant disease may be treated with a low-potency topical steroid (e.g., hydrocortisone 1%) or antifungal azole (e.g., ketoconazole 2%) for 1–2 weeks. Topical steroid may be preferred if there is a significant inflammatory component 11.References
- Nudging hair shedding by antidandruff shampoos. A comparison of 1% ketoconazole, 1% piroctone olamine and 1% zinc pyrithione formulations. Piérard-Franchimont C, Goffin V, Henry F, Uhoda I, Braham C, Piérard GE. Int J Cosmet Sci. 2002 Oct; 24(5):249-56. https://doi.org/10.1046/j.1467-2494.2002.00145.x
- Therapies for pediatric seborrheic dermatitis. Poindexter GB, Burkhart CN, Morrell DS. Pediatr Ann. 2009 Jun; 38(6):333-8. https://www.ncbi.nlm.nih.gov/pubmed/19588677/
- Skin diseases associated with Malassezia species. Gupta AK, Batra R, Bluhm R, Boekhout T, Dawson TL Jr. J Am Acad Dermatol. 2004 Nov; 51(5):785-98. https://www.ncbi.nlm.nih.gov/pubmed/15523360/
- Gupta AK. A random survey concerning aspects of acne rosacea. J Cutan Med Surg. 2001;5
- Bolognia JL, Jorizzo JL, Rapini RP, et al. Dermatology. 2. Spain: Elsevier; 2008.
- Foley P, Zuo Y, Plunkett A, et al. The frequency of common skin conditions in preschool-aged children in Australia: seborrheic dermatitis and pityriasis capitis. Arch Dermatol. 2003;139(3):318. https://jamanetwork.com/journals/jamadermatology/fullarticle/479236
- Kim GK. Seborrheic Dermatitis and Malassezia species: How Are They Related? Del Rosso JQ, ed. The Journal of Clinical and Aesthetic Dermatology. 2009;2(11):14-17. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2923939/
- Antifungal agents: mode of action, mechanisms of resistance, and correlation of these mechanisms with bacterial resistance. Ghannoum MA, Rice LB. Clin Microbiol Rev. 1999 Oct; 12(4):501-17.
- Bergrant IM, Faegemann J, Voog E, Lowhagen GB. Pytirosporum ovale and seborrhoeic dermatitis in HIV-seropositive and HIV-seronegative men. Quantitative cultures and serological studies. Journal of the European Academy of Dermatology & Venereology. 1996;6(2):147–51. DOI: 10.1111/j.1468-3083.1996.tb00158.x
- Higgins JPT, Green S. Cochrane Handbook for Systematic reviews of Interventions Version 5.1.0 [updated March 2011]. The Cochrane Collaboration 2011. www.cochrane-handbook.org. The Cochrane Collaboration
- Okokon EO, Verbeek JH, Ruotsalainen JH, Ojo OA, Bakhoya VN. Topical antifungals for seborrhoeic dermatitis. The Cochrane Database of Systematic Reviews. 2015;(4):CD008138. doi:10.1002/14651858.CD008138.pub2. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4448221/