ANSWER
The correct answer is eczema/atopic dermatitis (choice “c”).
Patients with eczema have a low threshold for itching, so they scratch, often making the condition appear far worse than it really is. In such cases, it’s typical for the problem to be mistaken for impetigo (choice “a”) or yeast infection (choice “d”). The latter, much like psoriasis (choice “b”), is quite rare in the perioral area. Furthermore, the patient had no indicative signs of psoriasis.
DISCUSSION
Eczema is one of several manifestations of atopic dermatitis, a syndrome that affects more than 20% of newborns in this country. These children have extraordinarily dry, thin skin that overreacts to wetting and drying, as well as scratching. Certain areas are especially prone to these changes and consequently develop scaling and itching.
The perioral area is one, in large part because it is kept moist by food, drink, nasal secretions, and saliva (due to habitual lip licking). The scaly rash becomes inflamed; on people with skin of color, this frequently manifests with hyperpigmentation.
When picked enough, this type of rash can become impetiginized—that is, superficially infected with staph or strep. But in this patient’s case, antibiotics were of no practical use.
A topical steroid ointment (hydrocortisone 2.5%) was used, and the patient was urged to stop picking (or licking!) and to use moisturizers (eg, petroleum jelly). The family was educated about the problem and its origins, and the parents were reassured of the self-limiting nature of postinflammatory hyperpigmentation (a major source of concern).
In this case, the key to making the correct diagnosis was the significance of the personal and family history of atopy—and an appreciation for how common atopic dermatitis and associated eczema are.