What is chronic suppurative otitis media (CSOM)?
CSOM is an inflammatory condition of the ear that causes recurrent ear discharge (otorrhoea) through a perforation of the ear drum (tympanic membrane). The disease usually begins in childhood, as a spontaneous tympanic perforation resulting from an acute infection of the middle ear, known as acute otitis media (AOM), or as a sequel of less severe forms of otitis media (otitis media with effusion).
What is the prevalence of CSOM?
Prevalence surveys, which vary widely in methodology, estimate that the global burden of illness from CSOM may involve 65 to 330 million individuals with draining ears. According to the 2004 WHO report on CSOM, the prevalence of CSOM ranges from less than 1% in developed countries (such as the Denmark, Finland, UK and USA), to as high as 30% to 46% among certain groups, such as the Inuits of Alaska, Australian aboriginals and others. The report categorized the countries for which data were available based on the prevalence of CSOM into lowest, low, high and highest. The lowest were those countries with prevalence below 1% (mentioned above). Countries with low prevalence included Brazil and Kenya (1–2%). High prevalence (2–4%) was reported from Angola, China, Malaysia, Nigeria, the Philippines, the Republic of Korea, Thailand and Viet Nam. Highest prevalence (more than 6%) was found in Greenland, India, the United Republic of Tanzania and the Solomon Islands, and among the Australian aborigines.
Who is affected?
The infection is most commonly acquired in children aged up to 6 years, and peaks around 2 years of age. However, the condition persists in early and middle adulthood, unless treated. Most developing countries have a predominantly young population in whom CSOM is most prevalent.
What are the types of CSOM?
CSOM may be active or inactive. Active CSOM is associated with an actively discharging ear, whereas inactive CSOM involves a dry perforation. There are two types of CSOM, depending on the nature of the pathology:
- Tubotympanic/safe type: associated with tympanic membrane perforation and recurrent or persistent ear discharge. Episodes of upper respiratory tract infections and entry of water into the middle ear can trigger the discharge.
- Atticoantral/unsafe type: often associated with the presence of cholesteatoma or granulations. Cholesteatoma possesses bone-eroding properties and this condition has the potential to cause life-threatening complications, such as brain abscess, subdural and extradural abscesses, meningitis, hydrocephalus and encephalitis.
What is the possible impact of CSOM on the individual?
- Hearing loss: CSOM typically produces a conductive type of hearing loss, which may be mild or moderate. The hearing loss is due to perforation of the ear drum or disruption of the tiny bones (ossicles) that help to transmit sounds within the ear. It may also lead to cochlear hair cell damage, resulting in sensorineural or a mixed type of hearing loss. Based on the regional hearing impairment prevalence estimates, WHO estimated that about 164 million cases of hearing loss may be due to CSOM, and that 90% of these would be in developing countries. The hearing loss associated with CSOM can vary from mild to severe.
Given the prolonged duration of this condition and the severity of hearing loss, CSOM in children may inhibit their language and cognitive development. This may have a further impact on the child’s education, and the academic and social outcomes of the affected children.
- Death and disability: Mortality and disabilities caused by CSOM are primarily related to complications of CSOM. In 1990, about 28 000 deaths worldwide, mostly among developing countries, were attributed to otitis media. These are mainly due to complications such as intracranial abscesses and meningitis. Other complications include labyrinthitis, facial paralysis and jugular vein thrombosis.
Can CSOM be treated?
CSOM can be effectively treated by a variety of medical and surgical means. Use of oral antibiotics, local antibiotic ear drops, ear wicking and dry mopping are often effective in controlling the active infection. However, surgical management is required for:
- Reconstruction of tympanic membrane and ossicles in case of tubotympanic pathology;
- Eradication of the disease and reconstruction of the hearing mechanism in patients with cholesteatoma. Surgical exploration is essential in such cases to ensure that the condition does not progress to the stage of complications.
Can CSOM be prevented?
There are opportunities for prevention at all levels of health services particularly in the community and at the primary level of health care. Many of these opportunities can be implemented through a programme of primary ear care incorporated into primary health care. These include measures such as:
- Early identification and adequate management of acute otitis media, which can significantly reduce the burden of chronic suppurative otitis media;
- Control of risk factors, such as proper hygiene, avoiding trauma to ear, avoiding entry of dirty water in the ears and proper posture during breastfeeding;
- Immunization against measles, Haemophilus influenzae and pneumococcal disease to prevent upper respiratory tract infections which predispose to otitis media;
- Pre-school and school-screening programmes for early identification and management of otitis media.
The measures required to prevent CSOM and its complications are:
- H—Hygiene of the ear
- E—Early management of acute otitis media
- R—Raising awareness
What is WHO doing?
- Assisting Members States to develop suitable programmes for primary ear and hearing care, integrated into the primary health care system of the country;
- Providing technical resources and guidance for training;
- Developing and disseminating guidance to address the major preventable causes of hearing loss; and
- Raising awareness about hearing loss as well as the opportunities for prevention, identification and management.