MYSTERIOUS EAR PAIN
What do you advise for a patient who has left-sided ear pain despite a normal ear exam? There is no pharyngitis, no temporomandibular joint disease, and no dental problems. The patient has no history of allergies. She tried pseudoephedrine (Sudafed), but it did not relieve her symptoms.
—Jolly Philip, MD, Sunnyvale, Calif.
The differential diagnosis for otalgia is extremely broad because of the complex sensory innervation of the ear by multiple cranial and cervical nerves. Noxious stimulation of any branch of these nerves can lead to the sensation of otalgia. As such, pathology of virtually any structure in the head and neck that shares innervation with the ear must be considered. Dental disorders are the most common cause of referred pain to the ear, particularly temporomandibular joint syndrome, and you were wise to evaluate for them. Often consultation with a dentist is useful since there may be subtle signs of bruxism, caries, and ill-fitting dentures that can be easily missed by an internist without special training. Sinusitis is also a very common cause of otalgia, and your patient’s failed trial of pseudoephedrine does not rule this out. You may want to consider sinus imaging. A careful assessment of the neck is also essential since pain may be referred from cervical osteoarthritis or cervical myofascial pain syndrome. The nasopharynx, oropharynx, hypopharynx, and larynx all share sensory innervation with the ear via branches of the vagus and glossopharyngeal nerves, and rhinoscopy, nasopharyngoscopy, and indirect laryngoscopy should all be performed. Even irritation of the esophagus, bronchi, and heart can rarely lead to referred otalgia because of shared innervation from the vagus nerve. There are many other causes of referred otalgia, and you may find it useful to request consultation with an otolaryngologist.
—Daniel G. Tobin, MD (114-24)