20.3 Oral Cavity, Salivary Gland, Laryngeal & Taste and Smell Disorders

1. Diseases of the Oral Mucosa and Tongue

The mouth is the most accessible mucosal surface in the body, and the exam uses it as a window onto systemic disease and malignancy.

White and red patches

The operational rule: any oral lesion persisting beyond two weeks requires biopsy. Smoking, smokeless tobacco, alcohol and human papillomavirus are the major risk factors for oral squamous cell carcinoma, and the lateral border and ventral surface of the tongue and the floor of the mouth are the highest-risk sites.

Ulcers

• Recurrent aphthous stomatitis — painful, shallow, round ulcers with an erythematous halo on non-keratinized mucosa, healing in 1 to 2 weeks. Usually idiopathic, but recurrent or severe ulceration warrants evaluation for celiac disease, inflammatory bowel disease, iron, folate, B12 or zinc deficiency, HIV, and Behcet disease (in which oral ulcers are required for diagnosis).
• Herpes simplex — clustered vesicles on keratinized mucosa (hard palate, gingiva) and the vermilion border, in contrast to aphthae.
• A solitary ulcer persisting beyond two to three weeks is carcinoma until biopsied.

Tongue findings

• Atrophic glossitis — smooth, red, depapillated tongue in iron, B12, folate, niacin or riboflavin deficiency
• Geographic tongue — benign migratory glossitis; asymptomatic and requires only reassurance
• Macroglossia — amyloidosis (particularly AL amyloidosis, often with periorbital purpura), hypothyroidism, acromegaly
• Angular cheilitis — candidal or nutritional; check iron and B vitamins and denture fit

Systemic clues in the mouth

Gingival hyperplasia from phenytoin, cyclosporine or calcium channel blockers; gingival bleeding in leukemia and thrombocytopenia; oral ulceration with pancytopenia after methotrexate; buccal pigmentation in Addison disease and Peutz-Jeghers syndrome; Koplik spots in measles.

2. Salivary Gland Disease

Parotid enlargement

The single most useful discriminator is unilateral versus bilateral, and painful versus painless.

Facial nerve palsy with a parotid mass means malignancy until proven otherwise, because the facial nerve runs through the gland and benign tumors displace rather than invade it.

Sjogren syndrome deserves emphasis: bilateral parotid enlargement with dry eyes and dry mouth, anti-Ro and anti-La antibodies, and a markedly increased risk of MALT lymphoma. Persistent, hard or asymmetric enlargement in a patient with Sjogren syndrome requires evaluation for lymphoma.

Xerostomia is most often medication-induced — anticholinergics, antidepressants, antihistamines, diuretics, opioids — and also follows head and neck radiation. It causes rampant dental caries, candidiasis and dysphagia; management includes reviewing medications, saliva substitutes, meticulous dental care and, in some cases, pilocarpine or cevimeline.

3. Pharyngitis, Epiglottitis and Deep Neck Infection

Pharyngitis

Most is viral. The Centor criteria — tonsillar exudate, tender anterior cervical adenopathy, fever, and absence of cough — estimate the probability of group A streptococcal infection and guide testing.

Treat confirmed group A streptococcal pharyngitis with penicillin or amoxicillin to prevent acute rheumatic fever (though not poststreptococcal glomerulonephritis) and suppurative complications.

Do not miss the mimics:

• Infectious mononucleosis — exudative pharyngitis with posterior cervical adenopathy, fatigue, splenomegaly and atypical lymphocytosis. Avoid amoxicillin, which produces a florid rash, and advise avoidance of contact sport because of splenic rupture risk.
• Acute HIV (retroviral) syndrome — pharyngitis without exudate, fever, rash, adenopathy and mucocutaneous ulcers. Antibody testing may be negative; HIV RNA is required.
• Gonococcal pharyngitis — often asymptomatic; requires a sexual history.
• Peritonsillar abscess — unilateral severe pain, trismus, a muffled hot-potato voice, and uvular deviation. Requires drainage.

Epiglottitis

An enumerated blueprint topic. Now predominantly an adult disease since Haemophilus influenzae type b vaccination.

Presentation: rapid onset of severe sore throat with odynophagia disproportionate to a normal-appearing oropharynx, muffled voice, drooling, and the tripod position. Stridor is a late and ominous sign.

Management priority: the airway. Avoid agitating the patient or examining the pharynx with a tongue depressor if there is any airway compromise. Definitive assessment is direct visualization by an experienced clinician in a setting prepared for emergency airway management, with intravenous antibiotics and corticosteroids.

Deep neck infections

• Ludwig angina — bilateral submandibular space cellulitis, usually odontogenic, causing tongue elevation and airway compromise. A surgical and airway emergency.
• Retropharyngeal abscess — neck pain, odynophagia, fever, neck stiffness; can extend into the mediastinum.
• Lemierre syndrome — Fusobacterium necrophorum pharyngitis progressing to septic internal jugular vein thrombophlebitis with septic pulmonary emboli. Suspect it in a young adult with pharyngitis followed by persistent fever, unilateral neck pain and pulmonary nodules.

4. Diseases of the Larynx and Airway

A separately named blueprint subsection.

Hoarseness lasting more than two to three weeks requires laryngoscopy, and this is the most testable statement in the subsection. Causes:

New hoarseness in a smoker is laryngeal cancer until proven otherwise. New hoarseness with a normal larynx should raise the possibility of a left vocal cord paralysis from an intrathoracic lesion, prompting chest imaging.

Angioedema of the larynx — from ACE inhibitors or hereditary angioedema — is an airway emergency in which the absence of urticaria points to a bradykinin mechanism that will not respond to epinephrine, antihistamines or corticosteroids.

5. Disturbances of Taste and Smell

Enumerated under disorders of the nose and paranasal sinuses.

Most reported taste loss is actually olfactory loss, because flavor perception is dominated by retronasal olfaction. True gustatory loss is uncommon.

Causes of olfactory dysfunction:

Two clinically important consequences: anosmia is a safety hazard — patients cannot detect smoke, gas leaks or spoiled food — and it commonly causes reduced appetite, weight loss and depression, which are particularly consequential in older adults.

Unilateral olfactory loss, or loss with neurologic findings, warrants imaging. Persistent post-viral loss may improve slowly over months, and olfactory training has modest supporting evidence.