Otorrhea

In adults and children, otorrhea can arise from numerous sources (external ear canal, middle ear, mastoid) and may have a variety of etiologies (Box 156-1). Diagnostic considerations and subsequent treatment plans are directed by the source of the otorrhea; the age of the patient; the type of otorrhea (clear, mucoid, purulent, or bloody); the nature of the drainage (acute, chronic, or pulsatile); and the presence of other symptoms, such as otalgia, neurologic deficits, or associated systemic disease or symptoms. Evaluation requires meticulous suctioning of secretions under a microscope to identify the source of the drainage, and to differentiate between a primary infection or purulent drainage occurring secondary to an underlying inflammatory process.

Common causes of otorrhea differ between adults and children. In children, otorrhea is caused most commonly by either acute otitis media with tympanic membrane rupture or chronic otitis media in the presence of a tympanic membrane perforation. In adults, otorrhea results most commonly from either external otitis or chronic otitis media with a perforation. The initial history and physical examination should be directed toward establishing the time course of the symptom and the source of the otorrhea (ear canal, middle ear, mastoid).

The diagnosis of external otitis as the source of purulent otorrhea is suggested by a history of ear trauma or swimming-related water contamination of the canal. Trauma resulting in external otitis may occur from the use of cotton-tip swabs, irrigators for cerumen removal, in-the-canal hearing aids, or digital ear thermometers. A history of otalgia and drainage after swimming easily leads to a diagnosis of external otitis. Although typically painful, there are usually no additional systemic symptoms associated with this localized infection. The typical findings on physical examination include an exquisitely tender ear canal that is partially to completely obstructed by edematous skin, and associated with preauricular tenderness.

Purulent otorrhea may develop secondarily in patients with chronic dermatitis or eczema of the ear canal, without any prior history of trauma or water contamination. Bacterial or fungal infections may complicate this chronic skin condition. Symptoms of chronic dermatitis of the ear canal include complaints of dry, itchy ears. Secondary infection of chronic dermatitis of the ear canal is usually painless. Important points include a history of recent use of topical antibiotic ointments or solutions that may cause an localized allergic skin reaction with canal pruritus, edema, and purulent drainage. Physical examination should document the presence of fungal hyphae in the canal, keratin debris from chronic dermatitis, or, uncommonly, a canal cholesteatoma or keratoma. After suctioning all purulent material from the canal, the tympanic membrane must be examined for evidence of a retained foreign body, such as a pressure equalizing tube with localized granulation tissue, as the source of the otorrhea.

The most common bacterial pathogens causing external otitis are Pseudomonas aeruginosa and Staphylococcus aureus. Less commonly, other aerobic, facultative, and anaerobic organisms have been cultured from infected ears. Rarely, external otitis results from a local or regional infection that involves the ear secondarily. Actinomyces israelii is an anaerobic gram-positive bacterium that can cause external otitis from a primary dental or parotid infection. This infection may manifest as refractory otitis externa with granulation tissue in the ear canal and thick yellow otorrhea. Recognition of this entity is important because treatment involves surgical débridement and prolonged antibiotic therapy.¹

Malignant or necrotizing external otitis is a locally aggressive, potentially progressive form of otitis externa. Inflammation and necrosis can extend beyond the ear canal skin to involve underlying cartilage and bone. Extensive disease involves local and regional osteomyelitis of the temporal bone, resulting in severe, deep ear pain. Malignant otitis externa occurs most commonly in adults. The diagnosis should be considered, however, in children with poor general health or concurrent systemic disease with acute onset of painful otorrhea. Fifteen cases of malignant external otitis occurring in infants and children 2 months to 15 years old have been reported in the literature.^2,³ Risk factors in these patients included poor general health, immunosuppression, and diabetes mellitus. Common presenting findings on physical examination include granulation tissue within the external auditory canal, preauricular and auricular edema and erythema, tympanic membrane necrosis, and facial nerve paralysis. P. aeruginosa is the most common causative organism in children and adults with malignant external otitis.

Fungal infections of the ear (otomycoses) are typically limited to the external ear canal as a superficial infection. Rarely, these infections are invasive and involve the temporal bone. Common fungal species infecting the external ear canal are Aspergillus niger and Candida albicans. The former is easily recognized as pigmented fungal tufts atop a tangle of hyphal threads resembling a ball of cotton. Candida spp. also may colonize the ear canal, especially in patients previously treated with prolonged courses of antibiotic eardrops. A canal infected with Candida appears wet and macerated, filled with soft, curdlike debris. If the fungal infection has an associated bacterial component, the fungal elements may not be immediately evident. Rarely, the external ear canal and mastoid are primarily involved with coccidioidomycosis, which may resemble eczema or an allergic dermatitis.⁴

Secondary mycosis of the temporal bone is quite rare and may arise from a primary focus of infection involving the meninges or the paranasal sinuses. Causative agents include Cryptococcus, Candida, Blastomyces, and Mucor. Primary otogenic invasive fungal infections can occur in immunocompromised hosts who are human immunodeficiency virus positive, elderly individuals, and patients with diabetes mellitus. These cases may develop invasive fungal disease within the mastoid and temporal bones, resulting in rapidly progressive hearing loss and facial paralysis. Aspergillus fumigatus and Aspergillus flavus are sources of invasive fungal mastoiditis with serious morbidity and mortality.

An uncommon cause of purulent otorrhea arising from the external canal in children is infection of a first branchial cleft cyst. In some forms of this congenital anomaly, there is a sinus tract adjacent to the external canal causing localized edema, whereas in others a fistula may be present with an external opening into the external ear canal. The anomaly may not be recognized until drainage and swelling of the ear canal occur. An even rarer source of secondary external canal otorrhea in children and adults is a primary infection of the parotid gland that extends into the external ear canal through the fissures of Santorini. These fibrous channels within the cartilaginous ear canal can serve as a direct route of disease extension.

Severe otalgia associated with bloody or serous otorrhea should prompt examination of the canal and tympanic membrane for evidence of vesicles. Bullous external otitis and myringitis result in hemorrhagic vesicles on the bony external canal and tympanic membrane. This uncommon infection causes exquisite ear pain out of proportion to the physical examination. The infection may be viral, but Mycoplasma pneumoniae and Haemophilus influenzae have also been cultured from the vesicles. Conductive hearing loss secondary to an associated middle ear effusion often accompanies the localized infection. A mixed loss with a significant sensorineural component has been shown in 30% to 65% of cases of bullous myringitis in which audiometric assessment was performed. The hearing loss completely resolved in 60% of cases.^5,⁶

Herpes zoster oticus (Ramsay Hunt syndrome) should be considered if vesicles with an erythematous base are evident on the external canal, pinna, or soft palate. Significant otalgia described as a burning sensation is present with this infection, along with hearing loss, vertigo, and facial paralysis.

Tympanic Membrane, Middle Ear, and Mastoid Sources of Otorrhea

If the physical examination shows a normal-appearing external ear canal, the source of the otorrhea is the tympanic membrane, the middle ear, or the mastoid. Acute otitis media, chronic otitis media, and cholesteatoma are the most common sources of purulent or mucoid drainage from the middle ear and mastoid. Less common causes of chronic otorrhea from the middle ear and mastoid are neoplasms that become secondarily infected and systemic diseases with otologic manifestations.

If a patient with chronic otorrhea has undergone prior mastoid surgery, the physical examination should be directed toward establishing whether the drainage is from a superficial infection of the mastoid cavity or is caused by recurrent or residual mastoid disease. When the mastoid cavity is inspected, any anatomic factors should be noted that predispose toward poor aeration and bowl hygiene, such as a small meatus, high facial ridge, or large dependent mastoid tip. In these cases, the tympanic membrane may appear normal, and the middle ear may be aerated, but because of poor hygiene the mastoid bowl collects debris, and a superficial infection develops. The infection may be fungal or bacterial in nature; examination with meticulous cleaning under a microscope establishes the diagnosis.

In most cases, débridement and treatment with topical antifungal or antimicrobial eardrops or acidifying and drying agents, such as boric acid and alcohol solution, or dilute vinegar solution, suffice as management. In chronic infection, granulation tissue and mucosalized epithelium in the bowl can develop, however, requiring more aggressive treatment with chemical cauterization. Meticulous inspection of the mastoid bowl also reveals evidence of retained mastoid air cells or recurrent cholesteatoma debris as the cause of recurrent otorrhea. Revision mastoid surgery is usually required to eliminate these sources of infection.

In the case of otorrhea from acute otitis media, the drainage may be bloody, mixed with mucus, or mucopurulent, and is typically short-lived. Bloody or purulent otorrhea associated with pain also may occur either immediately or in a delayed fashion after placement of pressure equalization tubes. This otorrhea may occur because of granulation tissue obstructing the tube lumen, middle ear contamination after bathing or swimming, acute otitis media, or reflux of nasopharyngeal secretions through the eustachian tube into the middle ear.

Neglected or inadequately treated acute or chronic otitis media may progress to acute coalescent mastoiditis or chronic bacterial otomastoiditis. Typically, acute otomastoiditis manifests with otalgia, mastoid tenderness, and purulent drainage from the middle ear. Uncommonly, mastoiditis may result from obstruction of the aditus ad antrum; the tympanic membrane and middle ear appear normal in this situation. In acute mastoiditis, the ear canal typically is edematous and tender, resembling external otitis with retroauricular extension. In addition to external canal edema, patients with acute mastoiditis may have auricle protrusion, mastoid tenderness, and swelling, and possibly systemic symptoms of fever. Additional symptoms may be present if there are aural or intracranial complications of the acute or chronic infection. Aural complications include subperiosteal abscess, petrositis, facial paralysis, and labyrinthitis. Intracranial complications include extradural abscess; thrombosis or thrombophlebitis of the sigmoid sinus, transverse sinus, or sagittal sinus; subdural abscess; brain abscess; meningitis; and otitic hydrocephalus. A high index of suspicion and a thorough neurologic examination are required to detect possible aural and intracranial complications of a mastoid infection.

Acquired cholesteatoma is a common cause of painless, recurrent purulent otorrhea in adults and children. The otorrhea may be scant or profuse depending on the extent of the disease, and whether the keratin debris is infected. There is usually an associated long-standing hearing loss. Vestibular symptoms are typically not present, unless there is extensive bone destruction by the cholesteatoma. Erosion of the lateral semicircular canal with formation of a labyrinthine fistula may occur, and the patient may note dysequilibrium that is either spontaneous or induced by loud sounds (Tullio’s phenomenon) or positive pressure applied to the external ear canal. Diagnosis of cholesteatoma as the source of otorrhea is evident after meticulous cleaning of the ear canal and examination with binocular microscopy. Typically, a retraction pocket is seen in the posterosuperior quadrant of the tympanic membrane or in the pars flaccida region. The otorrhea and keratin debris emanating from the abnormal retraction are indicative of the acquired cholesteatoma.

Granular myringitis is an uncommon, idiopathic, inflammatory process involving the tympanic membrane. Granulation tissue and mucosalized epithelium extend over patchy areas of the tympanic membrane. In extensive cases, the entire tympanic membrane is thickened, and the granulation tissue exudes a thin transudate that may become secondarily infected.⁷

Systemic Disease Associated with Otorrhea

Noninfectious Causes

Granulomatous diseases of the temporal bone are uncommon. Presenting symptoms can mimic acute or chronic mastoiditis. Children with histiocytosis of the temporal bone can present with symptoms of painful purulent or bloody otorrhea. The three forms of histiocytosis (eosinophilic granuloma, Letterer-Siwe disease, and Hand-Schüller-Christian disease) all may involve the temporal bone.⁸ In addition to complaints of localized ear pain, there is evidence of suppurative drainage from the middle ear and mastoid, granulation tissue within the external auditory canal, local swelling of the postauricular or preauricular region, and bone destruction on radiographic imaging. Auditory and vestibular deficits, facial palsy, and lower cranial nerve deficits also may be present.⁹

Wegener’s granulomatosis is a granulomatous disorder consisting of inflammatory vasculitis of the upper and lower respiratory tracts and kidney. Almost one fourth of patients have otologic disease at some point during their illness. Otologic involvement may manifest as a serous otitis media or a suppurative otitis media with either thickening or perforation of the tympanic membrane. Granulation tissue may be present within the middle ear and mastoid, causing a painless chronic otorrhea that is associated with conductive, sensorineural, or mixed hearing loss.¹⁰ A high index of suspicion and confirmation with an elevated cytoplasmic antineutrophil cytoplasmic autoantibody titer facilitate the diagnosis.

Churg-Strauss syndrome is an autoimmune disease that may have otologic manifestations in the late stages of the disease. Asthma, recurrent sinusitis, peripheral neuropathy, eosinophilic infiltrates, systemic vasculitis, and peripheral eosinophilia are hallmarks of the disease. In advanced disease, otologic involvement may include a dense aural discharge, granulomatous eosinophilic infiltrates of the middle ear and mastoid, and severe to profound mixed hearing loss. Recognition of this entity is important because the disease is highly responsive to systemic steroids.¹¹

Infectious Causes

Aural tuberculosis and nontuberculous mycobacterial mastoiditis are granulomatous infections with presentations that may mimic either otitis externa or chronic otomastoiditis in adults or children. The typical history is that of an indolent infection of the external canal or middle ear with chronic painless otorrhea that is thin, watery, or serous in nature. In documented cases of aural tuberculosis, patients have had acute otalgia with purulent drainage when a bacterial superinfection is present. Typically, patients with aural tuberculosis do not have a history of pulmonary infection or exposure to a known source of tuberculosis. The diagnosis of tuberculous or atypical mycobacterial otomastoiditis is suspected when the infection fails to clear after multiple treatments with antibiotics. The ear canal and middle ear have granulation tissue, polyps, and inflammatory tissue, all of which may be diffusely destructive. In addition, there may be associated cervical, postauricular, or occasionally preauricular adenopathy and systemic symptoms of fever and malaise. The physical examination findings of a postauricular fistula associated with preauricular adenopathy, a denuded malleus, and multiple tympanic membrane perforations are reported to be pathognomonic of aural tuberculosis. Facial palsy associated with aural tuberculosis has been reported in 45% of patients.¹²^–¹⁴

Neoplastic Disease Causing Otorrhea

The presenting signs and symptoms of neoplastic involvement of the temporal bone include conductive and sensorineural hearing loss, otalgia, mastoiditis, facial nerve paralysis, and purulent or bloody otorrhea. The chronic purulent or bloody otorrhea can arise from neoplasms in the ear canal, middle ear, or mastoid. In adults, the most common neoplasms of the external canal causing otorrhea are squamous cell carcinoma, basal cell carcinoma, and ceruminous gland tumors. In the early stages of disease, these neoplasms may remain asymptomatic and unnoticed until a secondary bacterial infection develops. Advanced disease with temporal bone destruction is associated with chronic deep otalgia. Examination of the ear canal with binocular microscopy after removal of purulent debris may reveal the tumor as an erosive or fungating lesion. These lesions also may manifest as persistent granulation tissue that is refractory to routine management. Biopsy of the granulation tissue is indicated to rule out an underlying neoplastic process. Glomus tumors may be isolated to the middle ear or jugular foramen region and usually do not result in otorrhea. Large tumors may fill the mesotympanum and extend into the ear canal, however, resulting in bloody or purulent otorrhea. Performing a biopsy of glomus tumors extending into the ear canal can result in profuse bleeding and should be avoided.

Metastatic lesions to the temporal bone rarely manifest with otorrhea as an initial symptom. Primary tumors from the breast, lung, kidney, prostate, and stomach are the common sources of temporal bone metastatic lesions.¹⁵ These tumors metastasize predominantly to the petrous apex marrow through hematogenous dissemination. Metastatic involvement of the mastoid air cells and the tympanic cavity may occur. Lymphoma and leukemia also may infiltrate the petrous apex and subsequently involve mastoid air cells. Infiltration into the middle ear cleft along mucosal folds and into the fallopian canal and internal auditory canal is common.¹⁶

Acute myelogenous leukemia may involve the temporal bone by chloroma formations, which are masses of leukemic cells seen as discrete green collections within the mastoid or internal auditory canal. In children, uncommon neoplasms that result in otorrhea include histiocytosis, rhabdomyosarcoma, leukemia, and lymphoma. Because the presenting symptoms can resemble chronic otitis media with purulent or bloody otorrhea, granulation tissue, and aural polyps, diagnosis of the underlying neoplasm is often delayed.