Basics
Seborrheic dermatitis is a scaly skin condition that affects up to 5% of the human population.
In immunocompetent patients, it may be associated with an overgrowth of saprophytic Pityrosporum yeast on the scalp and face; it is not known whether the same is true in HIV-infected patients.
The frequency and severity of seborrheic dermatitis are increased in HIV-infected patients, for unknown reasons.
Seborrheic dermatitis appears commonly in hospitalized patients, probably because of the changes in hygiene (e.g., inability to shampoo the hair) experienced during illness.
For description and distribution of lesions, as well as management, see Chapter 15: InflAMmatory Eruptions of Unknown Cause.
Point to Remember Basics
Psoriasis is a scaly skin disease that affects 1% to 2% of the general population.
Psoriasis is not more common in HIV-infected patients, but it may present in a more severe or unusual form and may be recalcitrant to the usual treatments.
Reactive arthritis that often mimics psoriasis is the most severe manifestation (see Chapter 34: Cutaneous Manifestations of Systemic Disease) symptoms may include psoriatic lesions, arthritis, urethritis, and conjunctivitis. A new onset of severe psoriasis in a patient at risk for HIV should lead to HIV testing.
The combination of treatment with methotrexate and sulfonamides can lead to fatal bone marrow suppression.
The use of systemic steroids for treatment of psoriasis may result in life-threatening pustular psoriasis (see Chapter 14: Psoriasis for a more complete discussion).
Outline