Oral medicine: 7. red and pigmented lesions

Specialist referral may be indicated if the Practitioner feels:

This article covers first red lesions and then hyperpigmentation.

Red oral lesions are commonplace and usually associated with inflammation in, for example, mucosal infections. However, red lesions can also be sinister by signifying severe dysplasia in erythroplasia, or malignant neoplasms (Table 1).

Most red lesions are inflammatory, usually:

Geographic tongue (erythema migrans) is a very common condition and cause of sore tongue, affecting at least 1–2% of patients. There is a genetic background, and often a family history. Many patients with a fissured tongue (scrotal tongue) also have geographic tongue. Erythema migrans is associated with psoriasis in 4% and the histological appearances of both conditions are similar.

Some patients have atopic allergies, such as hay fever, and a few relate the oral lesions to various foods, eg cheese. A few have diabetes mellitus.

Geographic tongue typically involves the dorsum of the tongue, sometimes the ventrum and, on occasions, it may affect other oral mucosal sites. It is often asymptomatic, but a small minority of patients complain of soreness and these patients are virtually invariably middle-aged. If sore, this may be noted especially with acidic foods (eg tomatoes or citrus fruits) or cheese.