“David, Mrs Webb’s outside and she’s hopping mad. I think you ought to see her right away,” says Brenda, pharmacy technician at the Update Pharmacy, as she goes into pharmacist David Spencer’s office.

“OK. You’d better send her in here,” David replies.

A few moments later Brenda shows a very angry looking woman into the office, with a boy aged about six trailing behind her. David greets Mrs Webb politely and asks what the problem is.

“I’m going to sue you and report you to your authorities. And the manufacturer and Dr Adi-Varli too,” the woman says.

"You’ve harmed my child.”

David asks her to explain and Mrs Webb continues: “A couple of weeks ago I got a new moisturising cream on prescription for Justin’s eczema, and now he’s come out with white blotches over his face.

“My neighbour says that it’s something called vitiligo and that it’s incurable. And it’s this cream that’s caused it! ”
David replies: “I’m sorry to hear about it. But can I have a look at Justin’s face and ask a few questions to try to sort this out?”

Mrs Webb grudgingly agrees. David examines Justin’s face and asks him if the patches are sore or itchy, or anything, to which Justin answers no. He then asks Mrs Webb if there are any patches anywhere else. The answer is again no.

“Well,” David says, “I’m pretty sure that this is nothing serious, won’t last too long and is nothing to do with the cream. But you could ask Dr Adi-Varli if you want a second opinion.”

Questions

1. What is this likely to be?
2. What are the clinical features?
3. What is the treatment?
4. What advice could David give?

Answers

1. Pityriasis alba, a condition of unknown aetiology that occurs fairly commonly in children (incidence about 5 per cent) and even more frequently in atopic individuals. It normally resolves spontaneously within a few weeks to about a year. It has no connection with vitiligo. Reported contributory factors include excessive and unprotected sun exposure, poor hygiene, and environmental influences such as temperature, humidity and altitude.

2. The most common locations are on the cheeks, around the mouth and chin. The forehead, neck, shoulders, upper chest, and upper arms can also be affected. Lesions appear as several (two to 20) hypopigmented patches ranging in size from 1-4cm, which may have slight and subtle scale. There may be initial mild pruritic erythema. Patches appear more pronounced on dark or suntanned skin.

3. In most cases no treatment is required. For associated pruritis, emollients may help. For more severe and persistent cases, topical steroids, pimecrolimus or PUVA (psoralen plus ultraviolet light) may be prescribed. Hydrocortisone 1 per cent cream is available OTC, but it is not licensed for use on the face or at all for children aged under 10 years.

4. Keep the skin well moisturised. Use non-soap cleansers or moisturising soaps and apply emollients. Avoid sun exposure and wear sunscreen.

Based on Bassam, Z. Pityriasis alba. e-Medicine Dermatology. 2009. http://emedicine.medscape.com/article/1068868