This site is intended for health professionals only

What’s causing these white patches in the mouth?


The patient

A 37-year-old man was sent to me by his dentist because he had white patches on his buccal mucosa. The patient had noticed these lesions himself a few months previously because he had become aware of slight soreness in the area, especially when he ate hot or spicy foods.

He had assumed they were simple ulcers, but the dentist’s insistence had set his alarm bells ringing.

A glance at his summary screen showed no significant medical history and I confirmed that he had never smoked and did not drink heavily.

First instinct

There were smaller, but very similar lesions inside his other buccal mucosa – an appearance I have seen in patients who habitually chew their cheeks. This, in turn, can be a reflection of stress and tension and certainly, my patient seemed uptight. But he insisted this was purely a response to the dentist’s concern and that, prior to this, he had been fine.

And what the dentist was concerned about was, presumably, leukoplakia – though there remained other possibilities such as trauma from rough teeth, lichen planus and candida.

Differential diagnosis

• Habitual chewing

• Leukoplakia

• Trauma from rough teeth

• Lichen planus

• Candida

The lesions and their positions suggested trauma – but he denied cheek chewing and his dentist had given his teeth the all-clear.

Leukoplakia – regarded as a premalignant condition – was certainly a possibility. But his age, plus the fact he didn’t smoke or drink excessively, were against this diagnosis.

Lichen planus can cause a similar appearance, but there were no other lesions on mucous membranes or skin to support this possibility.

Oral thrush is fairly common, especially in users of inhaled steroids, but can usually be scraped off with a tongue depressor – which was not the case with this patient.

The hidden clue

Oral lesions, like dermatological problems, are seen by the GP as a welcome ‘quickie’. Which can mean a perfunctory history, often taken during, or even after, the examination. Not having come to any conclusion, I delved deeper – which was when he told me that, while he didn’t currently have any skin problems, he had suffered something in the past.

Getting on the right track

Prompted by this information, I took a proper look through his notes. This revealed some interesting information. Three years previously he’d been referred to a dermatologist about a perplexing rash on his legs, and was ultimately diagnosed as having lichen planus – a diagnosis that was either accidentally omitted from his computerised summary or deemed not important enough to warrant inclusion. Lichen planus certainly can recur in a minority of patients – so this diagnosis was instantly elevated to the top of the list of possibilities.

He was treated with oral steroid lozenges. A few weeks later he returned for review and was delighted to report complete resolution of his lesions.

Dr Keith Hopcroft is a GP in Laindon, Essex