Red face revisited: Endogenous dermatitis in the form of atopic dermatitis and seborrheic dermatitis

Seborrheic Dermatitis and Dandruff: A Comprehensive Review

“…The incidence among HIV patients ranges from 30% to 83% [ 9 , 10 ]. Most cases of SD in HIV patients are diagnosed with CD4+ T lymphocyte counts between 200 and 500/mm3 [ 3 , 14 , 15 ], and decreased CD4+ counts are often associated with worse SD. Fewer cases of SD were reported when CD4+ T cells were more than 500/mm3 [ 14 ].…”

“…Cradle cap is the most common clinical manifestation. SD in children is usually self-limited [ 3 , 15 ]. On the other hand, in adults, SD is a chronic or relapsing condition, featured by erythematous patches, with flaky, large, oily or dry scales in sebum-rich areas such as face (87.7%), scalp (70.3%), upper trunk (26.8%), lower extremities (2.3%), and upper extremities (1.3%) [ 5 , 7 , 29 ].…”

“…Pruritus is not an obligatory feature, but it is often present, mainly in scalp involvement [ 2 ]. The main complication is secondary bacterial infection, which increases the redness and exudate and local irritation [ 3 , 15 ].…”

Seborrheic Dermatitis

“…Seborrheic dermatitis has two incidence peaks, the first in the first three months of life and the second beginning at puberty, reaching its apex at 30 to 40 years of age [5][6][7]. The condition affects up to 70% of infants in the first 3 months of life [3,5] and 3 to 5% of young adults [7][8][9]. Seborrheic dermatitis is more common in males than females, presumably because androgens stimulate sebum production [6,8].…”

“…The high prevalence of infantile seborrheic dermatitis in early infancy can be explained by a transient surge of gonadotropins with a resulting rise in testosterone levels which peaks at 1 to 3 months of age. It is believed that the sebum permits growth and proliferation of commensal yeasts of the Malassezia (formerly known as Pityrosporum) family which, through the action of lipases, degrade lipids on the skin surface with production of unsaturated and saturated fatty acids [7,9]. The inflammation which causes hyperproliferation of stratum corneum (scaling) results from nonimmunogenic irritation due to unsaturated fatty acids and the cellular immune response to these yeasts [2,7,9].…”