The Stanford 25

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The Tongue in Diagnosis


The tongue manifests the features of many systemic illnesses and is a natural site for oral pathology.


Review the inspection of the tongue. Learn to recognize clinically important lingual lesions.


[Video forthcoming]

On physical examination, there are several characteristics of the tongue that should be noted:

  • Color
  • Texture
  • Size

Credit Wikimedia Commons

A normal tongue is a pinkish-red color and should have a rough-appearing texture on the dorsal surface due to the presence of papillae, which come in three varieties with different sizes.  The ventral surface of the tongue should similarly be pinkish-red, though some vasculature may be visible.  The tongue should fit comfortably in the mouth of the subject with the tip against the lower incisors.

In general, the examination of the tongue should occur in the following steps:

  1. Have the patient touch the tip of the tongue to the roof of their mouth and inspect the ventral surface.
  2. Have the patient protrude the tongue straight out and inspect for deviation, color, texture, and masses
  3. With gloved hands, hold the tongue with gauze in one hand while palpating the tongue between the thumb and index finger of the other, noting masses and areas of tenderness

Notable Findings

Smooth Tongue

As noted above, the tongue should have a rough-appearing texture to it, with papillae covering the surface.  The most common cause of a smooth tongue is the use of dentures, however it can also be a late sign of iron, folate or vitamin B12 deficiency.  Glossitis, by causing swelling of the tongue, may also cause the tongue to appear smooth.  Among women, low-estrogen states may cause a “menopausal glossitis”.

A classic smooth, beefy red tongue from vitamin B12 deficiency:

Discolored Tongue

The tongue may become discolored due to a variety of conditions.  Micronutrient deficiencies is perhaps the best-known of these, with B12 deficiency causing a sore, beefy-red tongue and pellagra causing a black tongue, although other B vitamin deficiencies also discolor the tongue.  Geographic tongue is a benign condition in which discolored, painless patches of the tongue appear and then reappear, often in a different distribution.

Hairy Tongue

Perhaps the best-known condition causing the tongue to appear hairy is Oral Hairy Leukoplakia, the result of EBV infection in HIV-positive individuals.  Chronic administration of antibiotics, particularly penicillins, can lead to fungal overgrowth on the tongue, particularly of aspergillus, leading to a tongue with black “hairs”.

White hairs along the side of the tongue, or Oral Hairy Leukoplakia, in this HIV-positive individual.

A black, hairy tongue consistent with aspergillus overgrowth


Furrowing of the tongue commonly results from one of two conditions, depending on the orientation of the furrows.  If they are transverse across the tongue, they may be from a benign condition called scrotal tongue.  If they are longitudinal with the length of the tongue, however, they are the result of infection with syphilis.


Ulceration of the tongue has many different causes, a few of which will be discussed here.  In inspecting ulcers, it is important to note their size, number, color, distribution, and whether or not they cause the patient any discomfort.

Aphthous ulcers, or aphthous stomatitis, are a painful form of ulcer that is most frequently encountered.  It usually appears in one of several patterns: minor, major, or herpetiform.  Minor aphthous ulcers are usually 2-8mm in size and spontaneously heal within 14 days.  Major aphthous ulcers are >1cm in size and may scar when they heal.  Herpetiform ulcers are pin-point size, often multiple, and may coalesce to form a larger ulcer.  These ulcers may result in odynophagia when they occur toward the posterior surface of the oropharynx.

Recurrent aphthous ulceration (RAU, or RAS for stomatitis) may indicate an underlying systemic illness.  These include inflammatory bowel disease (Crohn’s and Ulcerative Colitis), Behçet’s Syndrome, pemphigus, herpes simplex, histoplasmosis, and reactive arthritis (Reiter’s Syndrome).  Other causes of RAU include drug reactions, Marshall Syndrome, and MAGIC (Mouth and Genital ulcers with Inflamed Cartilage) syndrome.  Additionally, the ulcers themselves may become infected, requiring treatment.

Of particular concern is a single erythematous, often painful ulcer that does not heal – this may indicate that the patient has lingual or oral cancer, particularly if the patient uses tobacco and/or alcohol.  Patient history and risk factors are important to note in these cases.


Assessment of the size of the tongue can help reveal several conditions of importance.  Microglossia may result from pseudobulbar palsy, the result of damage to the upper motor neurons of the corticobulbar tracts that innervate the tongue.  This results in a small, stiff tongue.  There may be an apparent microglossia resulting from ankyloglossia, a congenitally short lingual frenulum commonly called a “tongue tie”.

Assessment of macroglossia should include palpation of the sublingual glands; these will be displaced in true macroglossia.  Macroglossia may be congenitally present in individuals with acromegaly.  However, new-onset macroglossia in an adult is essentially pathognomonic for amyloidosis and should be treated as such until proven otherwise.


Fasciculations of the tongue are indicative of lower motor neuron injury. These may present with dysarthria or dysphagia.  Amyotrophic lateral sclerosis is of particular concern in individuals with new-onset of these.

Notable Conditions

Lingual Cancer

Lingual cancer is the second most-common head and neck cancer, after that of the labia.  Tobacco and alcohol use are both major risk-factors.  The patient will often present with a painful mass in the tongue or a non-healing ulcer.  There may be a history of leukoplakia, dysphagia, or dysarthria.  Physical exam may reveal a tender lump in the tongue on palpation, however physical examination may not reveal anything if the mass is toward the posterior end of the tongue.  A proper workup, which may include fine needle aspiration of the mass, is necessary for diagnosis.


Oral candidiasis, or thrush, is the result of infection of the oropharynx by Candida albicans.  This is most typically in patients with some form of immunocompromise, particularly HIV, diabetes, or chronic antibiotic use, which leads to fungal overgrowth.  The patient presents with painless, white plaques on the tongue or oropharynx which are easily scraped off.  Odynophagia concurrent with this suggests that the esophagus is also involved.  Treatment includes any of a number of antifungals, including a nystatin gargle.

Works Consulted

  1. LeBlond RF, Brown DD, DeGowin RL, “Chapter 7. The Head and Neck” (Chapter). LeBlond RF, Brown DD, DeGowin RL. DeGowin’s Diagnostic Examination. 9th ed. Available: Accessed 11/28/2010.
  2. Huguley, CM, “Chapter 130 The Tongue”(Chapter). Walker HK, Hall WD, Hurst JW (eds.). Clinical Methods: The History, Physical, and Laboratory Examinations. 3rd ed. Boston: Butterworths, 1990.  Available: Accessed 11/28/2010.
  3. “Chapter 6 The Head and Neck” (Chapter). Bickey LS, Szilagyi PG. Bates’ Guide to Physical Examination and History Taking. 9th ed. New York: Lippincott Williams & Wilkins, 2007.
  4. Masferrer E, Jucgla A. Geographic Tongue. NEJM 2009; 361:20.
  5. “Chapter 224 Approach to the Patient with Aphthous Stomatitis” (Chapter). Goroll AH, Mulley AG (eds.). Primary Care Medicine: Office Evaluation and Management of the Adult Patient.  6th ed. Philadelphia, PA: Lippincott Williams & Wilkins, 2009.
  6. “Chapter 10 The Mouth” (Chapter).  Clain A (ed.). Hamilton Bailey’s Demonstrations of Physical Signs in Clinical Surgery.  16th ed.  John Wright & Sons Ltd, 1980.
  7. Messadi DV, Younai F. Aphthous Ulcers.  Dermatologic Therapy 2010; 23(3):281-290.
  8. Chattopadhyay A, Shetty SV. Recurrent Aphthous Stomatitis Otolaryngologic Clinics of North America  2011;44(1):79-88

Further Reading

  1. National Institute of Dental and Craniofacial Research.  Detecting Oral Cancer: A Guide for Health Professionals.  Available:

Written by stanford25admin

June 7, 2010 at 3:45 pm

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