| What is seborrheic dermatitis? | • Seborrheic dermatitis (SD) or dandruff, is a
common skin condition that mainly affects the
scalp. It causes scaly patches, red skin and
stubborn dandruff
• It can also affect oily areas of the body: face,
sides of the nose, eyebrows, ears, eyelids and
chest
• SD may go away without treatment. It may need
many repeated treatments before the symptoms
decrease. And they may recur |
| What is clinical presentation of seborrheic dermatitis? | -Skin flakes (dandruff) on the scalp, hair, eyebrows, beard or mustache
-Patches of greasy skin covered with flaky white or yellow scales or crust on the scalp, face, sides of the nose, eyebrows, ears, eyelids, chest, armpits, groin area or under the breasts
-Red skin
-Itching
May be more severe with stress, cold dry season, cradke cap on scalp
Usually decreases starting the age of 6 months |
| How is SD pathogenesis? | Either Yeast (fungus Malassezia furfur seen in oil secretions of skin)
Or irregular immune response |
| How is evolution of SD? | Chronic w/outbreaks triggered by winter, emotions, stress, hormonal, improvement inconsistent by the sun, declines w/ progression of baldness |
| What are associated signs and risk factors of SD? | Neuro conditions (parkinson's, depression)
Weakened immunity (organ transplant recepients, HIV, alcoholic pancreatitis, cancers)
Recovery from stressful conditions like heart attack
Some medications. |
| What is the differential for SD? | • Psoriasis. This disorder also causes dandruff and red
skin covered with flakes and scales. With psoriasis,
usually more scaly, and scales are silvery white
• Atopic dermatitis: itchy, inflamed skin in the folds of
the elbows, on the backs of the knees or on the front
of the neck. It often recurs
• Tinea versicolor. This rash appears on the trunk but
usually isn't red like seborrheic dermatitis patches.
• Rosacea. This condition usually occurs on the face and
has very little scaliness
• Cutaneous lupus |
| What is tx of SD? | • scalp: shampoo antifungal with pyrethrine
zinc, sulfure of Selenium, keratolytics, tar
• Skin: special soap, antiseptics and imidazoles
• Corticosteroids: mild in short course if acute
• Lithium, piroctone olamine
• Calcineurin inhibitors: pimecrolimus and
tacrolimus
Shampoo:
• Pyrithione zinc (Dermazinc, Head & Shoulders)
• Selenium sulfide (Selsun Blue)
• Ketoconazole (Nizoral A-D)
• Tar (Neutrogena T/Gel, DHS Tar)
• Salicylic acid (Neutrogena T/Sal)
(excess shampoo leads to increase in SD) |
