Page 49 - LECTURE NOTES

Pityrosporum organisms are probably not the cause but a cofactor linked to a T-cell

depression, increased sebum levels, and an activation of the alternative complement
pathway.

Because seborrheic dermatitis is uncommon in preadolescent children, and Tinea

capitis is uncommon after adolescence, dandruff in a child is more likely to represent a

fungal infection. Commonly seborrheic dermatitis is secondarly infected by bacteria.

Treatment

Topical corticosteroids, creams, lotions

Systemic ketoconazole or shampoos can be given if it is sever.

Dandruff responds to more frequent shampooing. Salicylic acid, tar, selenium, sulfur,

and zinc all are effective in shampoos and may be alternated. Selenium sulfide (2.5%)
or ketoconazole shampoos may help by reducing P. ovule scalp reservoirs. When

sever Ketokonazole 200mg tab can be given for 2 to 3 week and Antibiotics if it is
infected

3.10.3. Lichen Simplex Chronicus

Lichen simplex chronicus (LSC) is thickening of the skin with variable scaling that

arises secondary to repetitive scratching or rubbing. LSC is not a primary process.
Rather, a person senses pruritus in a specific area of skin (with or without underlying

pathology) and causes mechanical trauma to the point of lichenification.

LSC is found on the skin in regions accessible to scratching. Pruritus provokes rubbing

that produces clinical lesions, but the underlying pathophysiology is unknown. A
relationship likely exists between central and peripheral neural tissue and inflammatory

cell products in the perception of itch and ensuing changes in LSC. The possible
interplay among primary lesions, psychic factors, and the intensity of pruritus additively

influence the extent and severity of LSC

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