Chronic otitis media is an otological condition with symptoms like painless otorrhea and hearing loss persisting for more than six weeks. It can occur with or without cholesteatoma and is associated with the formation of aural polyps, granulations, destruction of the ossicles and occasional complications like facial palsy, labyrinthitis and even intracranial abscess.
Chronic otitis media (COM) is a condition characterized by persistent, and recurrent aural symptoms lasting for more than six to twelve weeks  . Based on the middle ear mucosal pathology it has been classified as simple chronic otitis media, chronic cholesteatoma otitis media, chronic granulomatous otitis media (e.g. tuberculosis), and chronic otitis media associated with specific diseases (e.g. eosinophilic granuloma, eosinophilic otitis media, Wegener granulomatosis)     .
Risk factors associated with COM include acute otitis media, eustachian tube dysfunction, thermal /mechanical or chemical trauma, blast injuries, iatrogenic factors such as tympanostomy tube placement, and craniofacial anomalies like cri du chat syndrome, Down syndrome, cleft lip and/or cleft palate, and velocardiofacial syndrome.
Patients present with purulent, serous, mucoid or blood stained, occasionally foul smelling, painless otorrhea which may increase during episodes of upper respiratory tract infections. This is accompanied by either conductive or mixed or sensorineural hearing loss in the affected ear. There may be tympanic membrane perforation with granulations or even polyps in the middle ear. In granulomatous COM, the middle ear mucosa appears very pale with thin, serous otorrhea. Foul smelling and blood stained otorrhea are noticed in cholesteatomatous COM due to secondary gram-negative bacterial infection. Rarely patients can present with complications of COM like mastoiditis, facial palsy, labyrinthitis, vertigo, lateral sinus thrombophlebitis, petrositis, and even life-threatening intracranial abscess or meningitis . COM with cholesteatoma has a higher incidence of intra-temporal and intracranial complications as cholesteatoma causes osteitis and bone destruction   .
The diagnosis of COM is based on a history of chronic otorrhea, recurrent ear infections, and hearing loss . A thorough examination of the ear under a microscope or with an oto-endoscope along with suctioning of the discharge is essential to detect the pathology and the extent of the disease as well as to obtain the discharge for gram stain, microbiological culture, and antibiotic sensitivity. Routine laboratory tests like complete blood count, erythrocyte sedimentation rate are obtained prior to surgical intervention. Cerebrospinal fluid testing may have to be ordered in patients presenting with clinical features of meningitis. Audiological evaluation with a tuning fork and audiogram are performed in all cases of COM, as a routine, except in those presenting with life-threatening complications.
High resolution computed tomogram (HRCT) and magnetic resonance imaging (MRI) are indicated to detect complications like labyrinthitis, ossicular chain or temporal bone erosion, intracranial abscesses. HRCT of the temporal bone provides reliable information about mastoid, middle ear, and labyrinthine anatomy as well as pathology   . Spiral CT scan is superior to conventional CT scan in the diagnosis of cholesteatoma and other lesions associated with COM  .
An effective treatment of COM depends on the stage of the diagnosed infection. Early stage COM can be tackled with a combination of topical antibiotics and steroids. In case of systemic and large-scale infections, oral or parenteral administration of antibiotics is an advisable approach to fight the infection. During the treatment it is imperative to guarantee a dry middle ear cavity .
Medication options in the treatment of COM involve the prescription of ciprofloxacin, which offers a broad spectrum of antimicrobial activity; another possibility is to combine ciprofloxacin with dexamethasone to offer an additional anti-inflammatory treatment. The most widely used antibiotic in the context of COM is tobramycin because of its long and successful treatment history. However, there is a significant risk of vestibular and cochlear toxicity in case of its prolonged use, if the patient does not present with inflammation symptoms. Piperacillin can be taken into consideration for prescription, if the patient has been diagnosed with a pseudomonal infection. Ceftadizime is an excellent option for a systemic antibiotic treatment of COM, because it does not feature long-term side effects .
If medication measures fail to ease the symptoms of COM, a surgical intervention is necessary. The objectives of these procedures are the eradication of the source of inflammation, i.e. the removal of middle-ear mucosa, the preservation of the mastoid bone and a surgical remodeling of the middle ear in order to preserve and recover hearing. Recommended surgery options are a myringoplasty, a tympanoplasty and a mastoidectomy .
Patients usually respond well to antimicrobial agents. Children may have to prolong the antibiotic treatment to experience the desired effect. Chronic ear infections can be recurrent, so regular medical check-ups are advisable in any case.
Untreated COM offers a plethora of complications ranging from mastoiditis, cholesteastoma, tympanosclerosis, paralysis of the facial nerve, generic damage to the middle ear, epidural abscess in or around the brain to balance perturbations and speech issues. In rare cases, patients can develop complete deafness .
Surgical treatments also comes with possible side effects. The most dangerous possibility is a large-scale post-operative infection, which is why the use of perioperative antibiotics may be advisable. Taste disturbance may occur as a consequence of a damage to the tympani nerve. Further hearing loss can be found in case of a scarring of the tympanic membrane. Vertigo and temporary facial paralysis has often been reported in the immediate aftermath of the procedure .
However, a tympanoplastic procedure usually provides excellent healing chances in the vast majority of cases. Patients will soon be free of symptoms but regular post-operative checks are necessary to maintain a healthy middle ear.
The main cause of COM is an acute infection (acute otitis media, AOM) in the middle ear involving severe inflammation symptoms and the traumatic perforation of the tympanic membrane. COM usually develops as a consequence of a translocation of bacteria from the external auditory canal into the middle ear after the above-mentioned perforation of the tympanic membrane. The middle ear is usually dry and well-ventilated by constant air flow from the eustachian tube. Impaired air flow through the middle ear sets the stage for a possible infection of the middle ear. Clogging of the eustachian tube may thus be another cause of COM, which can occur as a consequence of allergies, post nasal drainage, sinus infections, an immature eustachian tube in children or viral infections of the upper respiratory tract  .
The probability of occurence is higher in children than in adults, as shown in a study reporting an almost two-fold higher chance of COM in children (0.9% in children vs. 0.5% in adults). In countries with a warmer climate, COM prevalence can be significantly smaller (e.g. 0.039% of Israeli children). Some ethnicities are more prone to develop COM for unknown reasons. Native Americans and Inuit people have a statistical chance of eight and twelve percent to develop COM, respectively. It has been speculated that a wider eustachian tube may play a role in increasing the odds of a chronic middle ear infection in these cases. People from Guam, Hong Kong, South Africa and the Solomon Islands may suffer from a similar predisposition .
COM typically results from an acute infection of the middle ear. The immune system attempts to resolve this infection with an inflammatory response. This response creates mucosal edema which may ulcerate in long-lasting inflammation scenarios and create a granulation tissue. Recurring episodes of infections, inflammations, ulcerations and granulation tissue formations can gradually deteriorate the middle ear bones and lead to severe complications of COM .
The infection is most frequently caused by the following bacteria in descending order of likelihood: Pseudomonas aeruginosa, Staphylococcus aureus, Proteusspecies and Klebsiella pneumoniae . Multicultural infections are possible, but rare. Anaerobes (Bacteroides, Peptostreptococcus, Peptococcus) and fungi (Aspergillus, Candida) have also been reported as possible infection causes .
There is no recipe to reliably prevent COM. Some lifestyle changes may, however, reduce the risk of infection. Snoring and mouth breathing are an early symptom for possibly enlarged adenoids which may increase the odds of a middle ear infection. High standards in everyday hygiene and a smoke-free home may reduce infection risks, too. After COM treatment it is imperative for the patients to keep their ears dry, in particular after daily showers and after swimming. Professional allergy controls in children may also reduce the risk.
Chronic otitis media is a major complication of an acute infection episode of the middle ear. Inflammation is usually caused by the migration of bacteria into the middle ear space. Clogging of this space creates a warm and damp micro-climate and leads to recurrent episodes of inflammation conducive to more serious symptoms that can result into a complete loss of hearing. Diagnosis must prove a perforated tympanic membrane and a mucosal infection of the inner ear based on culture extraction and/or imaging techniques. Topical and systemic antimicrobial treatments typically offer best healing chances. In severe cases, surgery must be considered in order to preserve middle ear structure. Patients are advised to regularly check back with their medical professionals to ascertain a dry and well-ventilated middle ear.
Chronic otitis media is a serious infection of the middle ear which requires immediate attention of a doctor. If left untreated, chronic otitis media can lead to severe and irreversible damage of the middle ear. After professional treatment, you will be required to keep your ear dry at all times and regularly consult a professional to ascertain the desired healing process. A smoke-free environment and high standards in everyday hygiene will likely help you keep future infections at bay.