The answer

Linda may have angular chelitis – sometimes known as angular stomatitis – which is inflammation of the skin at the corner of the mouth. The symptoms can include redness, cracking, scaling, bleeding and ulceration at one or both corners of the mouth, and there are various factors that increase the chance of it occurring, from wearing dentures and other oral appliances such as braces, contact allergies and nutritional defi ciencies, to dry skin and dermatitis.

It is also more common in individuals who tend to have wetter lips – for example, a child who sucks their thumb, an older person who has a propensity to drool, or someone who is a bit over-zealous about using mouthwash – and those who have a compromised immune system, for instance, patients with HIV. In many cases, microorganisms are present, most commonly the fungi Candida or bacteria in the Staphylococcus or Streptococcus families; the latter can usually be diagnosed by the presence of crusting, though sometimes swabs will be taken for testing.

Treatment depends on the cause, so if dentures or braces are implicated, the patient should have the fi tting checked. If hypersalivation is an issue, breaking the habit or using emollients can be all that is needed. Miconozole cream is the topical product of choice otherwise, as it works against fungal infections and has some bacteriostatic action, though this may need stepping up to a formulation that includes a topical steroid and/or antibacterial agent, or oral antifungals, if needed.