DermaDiagnosis
15 and Going Gray
A 15-year-old boy is embarrassed by persistent depigmentation that leaves the skin around his nose gray and scaly. Can you help by providing a...
ANSWER
The correct answer is to perform a punch biopsy (choice “b”). This will help establish the exact nature of the problem, which will dictate rational treatment.
The patient doesn’t have acne, so the suggested treatment options (choices “a,” “c,” and “d”) would be of no use. With cryotherapy, furthermore, there is a risk of leaving a permanent blemish on her skin.
DISCUSSION
A sample of one lesion was obtained via 3-mm punch biopsy and the resulting defect closed with a single suture. Pathologic examination showed the specimen to be a vellus hair cyst (VHC). In this case, it was one of many, making the diagnosis eruptive vellus hair cysts.
VHC, which can be acquired or inherited, typically manifests in the first two decades of life. In this developmental abnormality, a gradual disruption occurs between the proximal and distal portions of the vellus hair follicle, usually at the level of the infundibulum. As a result, the characteristic papule (which holds the retained hair) forms and the hair bulb atrophies.
The lesions may be solitary or appear in clusters on the body; they are easily mistaken for acne, milia, or even molluscum. As this case demonstrates, biopsy is often necessary to establish the correct diagnosis.
One final note about biopsy: It is best to incise each lesion with an 18-gauge needle tip or #11 blade and express the contents. This tedious process causes some discomfort for the patient, but it is quite effective and, if done correctly, should not leave a permanent mark on the skin.
