Basics
Description
- Seborrheic dermatitis (SD) is a multifactorial skin disease influenced by both host and environmental factors.
- Involves sebaceous areas of the body
- Including the scalp, face, back, chest, and intertriginous areas
- Characterized by greasy, yellow, scaly erythematous lesions
- Usually a self-limited condition in infants but can be a chronic, relapsing condition in adolescents and adults
Epidemiology
- Trimodal distribution: infants, adolescents, and adults >50 years of age
- Highest prevalence in first 3 months of life
- Affects approximately 10% of the general population and up to 70% of infants in the first 3 months of life
- No sex predilection in infants; however, in adolescents and adults, males are affected more commonly than females.
- Seasonal pattern: Prevalence of disease increases in winter months.
- Strong association between Malassezia species, a common commensal organism, and SD
Risk Factors
- There are no known genetic factors that contribute to disease.
- Hormonal effects: exposure to maternal estrogen in infancy and surge of androgens in puberty
- Immunocompromised status
- Impaired cellular immunity may contribute to pathogenesis of disease.
- Prevalence of SD in immunocompromised patients is significantly higher than in general population.
General Prevention
There are no known preventive measures.
Pathophysiology
- Androgens stimulate sebaceous glands, causing production of more sebum.
- Malassezia
- A lipophilic yeast that is normally found in sebum-rich areas of the skin
- Can break down skin sebum lipids, producing potentially inflammatory fatty acids
- In response to the inflammatory fatty acids, keratinocytes produce proinflammatory cytokines.
Etiology
Not completely known, although it was thought that yeast, androgens, and the local host immune response play a role in SD development.
Diagnosis
History
- Older children and adolescents: Ask about onset of puberty symptoms.
- Typically not pruritic
- Children and adolescents: Ask about symptoms and signs of immunocompromise such as frequent infections, failure to thrive, and chronic diarrhea.
- HIV and tuberculosis (TB) history
Physical Exam
- Infants: "cradle cap "
- Yellow, greasy adherent scales on the scalp
- Lesions may also occur on the forehead, eyebrows, eyelids, postauricular area, and nasolabial folds.
- No excoriations
- No hepatosplenomegaly
- Adolescents and adults
- Mild: dry, flaking scalp or face in areas of facial hair; no surrounding inflammation
- More severe SD: patchy, orange/yellow, greasy plaques in scalp, nasolabial folds, postauricular area, intertriginous areas, or other regions of increased sebaceous gland activity
- Blepharitis with erythema and scaling of the eyelid margins may also occur.
- No excoriations
- No hepatosplenomegaly
Diagnostic Tests & Interpretation
Lab
Primarily a clinical diagnosis; there are no specific tests for seborrhea.
Diagnostic Procedures/Other
Skin biopsy should be reserved for unusual or refractory cases of SD.
Pathologic Findings
- Skin biopsy findings
- Predominance of neutrophils in the scale crust at the margins of follicular ostia
- Yeast cells sometimes are visible within keratinocytes on special stains, but hyphae should not be present in SD.
Differential Diagnosis
- SD can be confused with infectious conditions of the skin, malignancy, or inflammatory disorders.
- Dermatophyte infections
- Tinea capitis, tinea faciei, and tinea corporis are also scaling lesions. The lesions are scaly but not typically greasy or plaque-like.
- Microscopic evaluation of lesion can differentiate it from SD by the presence of hyphae in dermatophyte infection.
- Malignancy/Langerhans cell histiocytosis (LCH)
- LCH may present with a scaly erythematous lesions in the same distribution as SD.
- Unlike SD, LCH may have the presence of small reddish-brown crusted papules or vesicles.
- In addition, there may be organ system involvement such as hepatosplenomegaly.
- LCH is refractory to typical treatment for SD.
- Immunologic
- Atopic dermatitis
- May present on the face of infants but typically spares the nasolabial folds
- May also involve the extensor aspects of the extremities
- Usually is pruritic
- Psoriasis vulgaris
- Typically presents as sharply defined plaques, bright red in color with thick silver scales
- Unlike SD, children with psoriasis may have nail changes such as nail pitting and onycholysis.
Treatment
- Treatment depends on presentation and age of patient.
- For infants, SD usually has a benign and self-limited course. Medications may not be necessary for the treatment of infant SD.
- Physical measures such as the application of emollients followed by the removal of scalp scales with a comb may improve symptoms.
- Examples of emollients include mineral oil, baby oil, or petroleum jelly.
- There have been some studies to suggest that the use of organic oils such as olive oil or vegetable oil may provide an excellent media for Malassezia overgrowth, potentially worsening SD.
- Frequent shampooing with a nonmedicated shampoo may also be beneficial.
Medication
- For infants who do not respond to conservative therapy or for older children/adults, medications will likely be necessary.
- Classes of drugs that should be considered are keratolytic, antifungal, and anti-inflammatory medications. At the current time, there is no evidence to support the use of one class of drug versus another.
- Keratolytics: Massage into scalp 2 " 3 times per week, leave on 5 minutes, then rinse.
- Salicylic acid
- Coal tar
- Shampoo
- Decreases sebum production
- Pyrithione zinc
- Most commonly used as a shampoo
- Also has antifungal properties
- Antifungals
- Selenium sulfide
- Antifungal and keratolytic effect
- Shampoo. Massage 5 " 10 mL of shampoo into wet scalp, leave on scalp 2 " 3 minutes, then rinse thoroughly.
- Usually, 2 applications each week for 2 weeks will provide control.
- Azoles: ketoconazole
- 1% or 2% gel, lotion, or shampoo
- Shampoo should be used twice per week (at least 3 days between doses) for up to 8 weeks. Caution: may cause eye irritation
- Gel or lotion should be used twice daily for up to 2 " 4 weeks.
- Ciclopirox: 1% shampoo
- Can be used in children >16 years old
- Massage into scalp, then rinse.
- Use 2 times per week (at least 3 days between doses) for up to 4 weeks.
- Anti-inflammatory therapies
- Corticosteroids
- Shampoo, foam, ointment, creams, or lotions
- There are multiple options; treatment will depend on severity of inflammation and age of patient.
- Ointments should be considered for more severe cases because skin absorption is improved.
- Foams can be used in hairy areas because of ease of application.
- Calcineurin inhibitors: tacrolimus ointment
- Can be used in children >2 years of age
- Fungicidal and anti-inflammatory properties
- Apply thin layer of 0.03% ointment to affected area twice daily until symptoms resolve or up to 6 weeks.
Complementary & Alternative Therapies
- Tea tree oil 5% has been demonstrated to be effective in treating scalp seborrhea.
- Other alternative nutritional therapies that have been considered are probiotics and omega-3 essential fatty acids. However, there are no sufficient data on effectiveness or safety in children.
Ongoing Care
Patient Education
- Response to treatment will likely occur in the first 2 weeks of therapy; however, long-term intermittent therapy may be required. Adolescents with SD may have a chronic course.
- The intermittent use of an antifungal shampoo can be used to prevent relapses.
Prognosis
- The infantile form will typically self-resolve by the end of the 1st year of life.
- Older children and adolescents may have a more chronic, relapsing course.
- If SD doesn 't respond to therapy within approximately 6 weeks, consider alternative diagnoses or underlying conditions such as immunodeficiency.
Additional Reading
- Berk T, Scheinfeld N. Seborrheic dermatitis. P T. 2010;35(6):348 " 352. [View Abstract]
- Cohen S. Should we treat infantile seborrheic dermatitis with topical antifungals or topical steroids? Arch Dis Child. 2004;89(3):288 " 289. [View Abstract]
- Dessinioti C, Katsambas A. Seborrheic dermatitis: etiology, risk factors, and treatments: facts and controversies. Clin Dermatol. 2013;31(4):343 " 351. [View Abstract]
- Gupta AK, Madzia SE, Batra R. Etiology and management of seborrheic dermatitis. Dermatology. 2004;208(2):89 " 93. [View Abstract]
- Gupta AK, Nicol K, Batra R. Role of antifungal agents in the treatment of seborrheic dermatitis. Am J Clin Dermatol. 2004;5(6):417 " 422. [View Abstract]
- Sarchell AC, Saurajen A, Bell C, et al. Treatment of dandruff with 5% tea tree oil shampoo. J Am Acad Dermatol. 2002;47(6):852 " 855. [View Abstract]
- Schwartz RA, Janusz CA, Janniger CK. Seborrheic dermatitis: an overview. Am Fam Physician. 2006;74(1):125 " 132. [View Abstract]
- Siegfried E, Glenn E. Use of olive oil for the treatment of seborrheic dermatitis in children. Arch Pediatr Adolesc Med. 2012;166(10):967. [View Abstract]
Codes
ICD09
- 690.10 Seborrheic dermatitis, unspecified
- 690.11 Seborrhea capitis
- 690.12 Seborrheic infantile dermatitis
- 690.18 Other seborrheic dermatitis
ICD10
- L21.9 Seborrheic dermatitis, unspecified
- L21.0 Seborrhea capitis
- L21.1 Seborrheic infantile dermatitis
- L21.8 Other seborrheic dermatitis
SNOMED
- 50563003 Seborrheic dermatitis (disorder)
- 156329007 Seborrheic dermatitis of scalp (disorder)
- 200776003 Infantile seborrheic dermatitis (disorder)
- 231797007 Seborrheic blepharitis
- 402210009 Facial seborrheic dermatitis (disorder)
- 238565002 Truncal seborrheic dermatitis (disorder)
FAQ
- Q: Is there a laboratory test to diagnose SD?
- A: There are no specific laboratory tests. It is a clinical diagnosis. If the diagnosis is unclear or refractory to treatment, consider a skin biopsy.
- Q: Are there seasonal changes in the course of SD?
- A: Some patients report worsening of symptoms in the winter months. Sunlight may improve patients ' symptoms. UV therapy is a treatment option for extensive SD.
- Q: Does SD cause permanent hair loss?
- A: SD may cause some hair loss acutely. However, patients can be reassured that it does not cause permanent hair loss.