This patient has rosacea, which presents as central facial erythema with transient papules or pustules. Burning and stinging may be present. The pathogenesis of rosacea is unknown. There are two types, erythematotelangiectatic (vascular) and papulopustular (inflammatory) rosacea. Vascular rosacea presents as persistent flushing, especially of the central face, with prominent telangiectasias. Pustules and papules are seen in the inflammatory variant, but in contrast to acne, rosacea pustules are not follicular based. Bulbous thickening of the nose (rhinophyma) can also occur. Eye involvement, with dry, gritty-feeling eyes and conjunctival injection, is common. Multiple studies have demonstrated that rosacea is associated with cutaneous inflammation; however, the trigger is highly debated. Alcohol, sun exposure, and other triggers can cause a transient increase in facial erythema but do not cause rosacea. Flushing is a common characteristic of rosacea; the differential diagnosis of this includes carcinoid syndrome, mastocytosis, and pheochromocytoma. The differential diagnosis for rosacea also includes entities that cause central facial erythema and/or inflammatory papules, namely acne, periorificial dermatitis, cutaneous lupus erythematosus, sarcoidosis, contact dermatitis (eczema), seborrheic dermatitis, actinic damage, and folliculitis due to Pityrosporum or Demodex spp.

The malar rash of acute cutaneous lupus erythematosus, typically seen in patients with systemic lupus erythematosus, is a transient erythematous patch over the cheeks that often spares the nasolabial fold. Certain forms of rosacea may resemble the rash of malar erythema, but patients with rosacea will often have a prominent telangiectatic component, as well as inflammatory papules, pustules, and occasionally rhinophymatous changes of the nose.

Periorificial dermatitis shares some clinical characteristics with rosacea. It occurs in both young children, commonly around the mouth and eyes, and adults, who are usually affected around the mouth. Monomorphous pink papules (1 to 2 mm) that sting or burn rather than itch are grouped around the mouth or eyes. Periorificial dermatitis is sometimes caused by the use of topical glucocorticoids on the face.

Seborrheic dermatitis causes white, scaling macules and papules that are sharply demarcated on yellowish-red skin and may be greasy or dry. Sticky crusts and fissures often develop behind the ears, and significant dandruff or scaling of the scalp frequently occurs. Seborrheic dermatitis may develop in a “butterfly”-shaped pattern but also may involve the nasolabial folds, eyebrows, and forehead. This condition usually improves during the summer and worsens in the fall and winter.