Geographic tongue is an inflammatory condition of the mucous membrane of the tongue, usually on its dorsal surface.
Affects approximately 2–3% of the general population.
Some sources report a prevalence of up to 14%. It is one of the most common tongue disorders in children.
Others report that the highest incidence occurs in the over 40 age group.
Females are sometimes reported to be more commonly affected than males, in a 2:1 ratio.
Characterized by areas of smooth, loss of lingual papillae.
The process migrates over time.
Results in a map-like appearance of the tongue.
Cause is unknown.
It is entirely benign.
It is not linked to an infection, and is not contagious.
No curative treatment exists.
May cause a burning sensation on the tongue, in some cases when eating hot, acidic, spicy or other kinds of foods.
Its appearance is variable from one person to the next and changes over time.
It is common for fissured and geographical conditions to coexist.
In health, the dorsal surface of the tongue is covered in tuft-like projections called lingual papilla.
Some papillae are associated with taste buds, which give the tongue an irregular surface texture and a white-pink color.
A geographic tongue is characterized by areas of atrophy and depapillation.
Such changes leaving an erythematous, darker red, and smoother surface than the unaffected areas.
The depapillated areas are well-demarcated, and bordered by a slightly raised, white, yellow or grey, serpiginous peripheral zone.
The initial lesion may appear as a white patch before depapillation occurs.
It typically occurs in multiple locations on the tongue and over time coalesces to form a typical map-like appearance.
With time the lesions alter their shape, size, and migrate to other areas
There is a predilection for the tip and sides of the tongue.
The entire dorsal surface at one time however may be involved.
The process goes through periods of remission and relapse.
The patches can come and go or change very quickly over days, weeks, or months.
It might last for up to a year.
Mucosal healing is suggested by loss of the white peripheral zone.
Some patients suggest that their condition worsens with stress.
About 1 in 10 people have mild discomfort or a burning or painful feeling, due to hot, spicy, or acidic foods, cigarette smoke or toothpaste
It is inversely associated with smoking and tobacco use.
It may be hereditary to some extent and is associated with several genes.
It is more common in people who have psoriasis or cracks and grooves on the top and sides of their tongue.
Reporteded linked with various human leukocyte antigens of HLA-DR5, HLA-DRW6 and HLA-Cw6 and decreased incidence in HLA-B51.
Vitamin B2 deficiency can cause geographic tongue.
The differential diagnosis includes oral lichen planus, atrophic glossitis,
erythematous candidiasis, leukoplakia, lupus erythematosus, glossitis, and chemical burns.
Its histopathologic appearance is similar to psoriasis:
Subepithelial T lymphocyte inflammatory infiltrate.
Migration of neutrophilic granulocytes into the epithelial layer, which may create superficial microabscesses.
Considered to be a type of glossitis.
It usually presents only on the dorsal 2/3 and lateral surfaces of the tongue,
An identical condition can occur on other mucosal sites in the mouth, such undersurface of the tongue, mucosa of the cheeks or lips, soft palate or floor of mouth.
Reassuring the patient that the condition is entirely benign is usually the only treatment.
Topical anesthetics can be used to provide temporary relief in symptomatic patients.
Some foods exacerbate or trigger the symptoms.
An uncontrolled trial where increased zinc intake showed some benefit in controlling the symptoms of geographic tongue.
It may disappear over time, but it is impossible to predict.