Many generalized dermatologic conditions can affect the face and scalp. This chapter discusses the acneiform eruptions, seborrheic dermatitis, erysipelas and facial cellulitis, herpes zoster, herpes simplex, tinea capitis and barbae, head lice, allergic contact dermatitis, and photosensitivity/sunburn. Impetigo and bullous impetigo are discussed in chapter 141, "Rashes in Infants and Children."
The acneiform eruptions include acne vulgaris, rosacea fulminans, dissecting cellulitis of the scalp, and acne keloidalis nuchae. Pathophysiology of these disorders is similar. Sebum secretion is increased within the sebaceous follicle by androgen stimulation. Keratin accumulates in the hair follicle as well as sebum. Host inflammation occurs, and the bacteria Propionibacterium acnes (gram-positive rods) proliferate and accumulate, intensifying inflammation. At this stage, an inflammatory papule or pustule occurs with an influx of neutrophils and helper T cells. In addition, marked inflammation can cause a nodule or cyst, and scarring can occur.
Acne fulminans is the most severe form of nodulocystic acne and may prompt patients to seek emergency medical attention. It usually affects males between the ages of 13 and 16 years. Clinical features include acute onset of suppurative cysts and nodules with ulcerations and hemorrhagic crusting on the face, chest, and back (Figure 250-1). Ulcerating lesions can lead to severe scarring. Systemic symptoms also occur and include osteolytic bone lesions of the clavicle and sternum, fever, arthralgias, myalgias, and hepatosplenomegaly. Diagnosis is clinical. Acute treatment includes administration of 40 to 60 milligrams of prednisone once daily. If the patient is already taking isotretinoin, continue the medication in conjunction with corticosteroids. Isotretinoin should not be started in the acute care setting. Refer to a dermatologist.
Nodulocystic acne. [Photo contributed by University of North Carolina Department of Dermatology.]
Rosacea fulminans, or pyoderma faciale, is an inflammatory cystic acneiform eruption on the central face of young women. The eruption may occur with or without a history of rosacea. Inflamed papules and pustules are present on the centrofacial region and can coalesce into large plaques. Diagnosis is clinical. Severe scarring can occur without treatment. Treatment is similar to that of acne fulminans—oral prednisone, 40 to 60 milligrams once daily, and referral to a dermatologist for consideration of isotretinoin.
Dissecting cellulitis of the scalp, also called perifolliculitis capitis abscedens et suffodiens, is an inflammatory and scarring disease of the scalp and neck. It occurs most commonly in young men of African descent. It consists of boggy tender nodules in multiple areas of the scalp and the neck (Figure 250-2). It is not a true cellulitis but is an intense inflammatory condition of the scalp. The nodules suppurate and develop interconnecting sinus tracts. Hair loss develops over these nodules, and permanent scarring, alopecia, and keloids can occur. If associated with acne conglobata, ...