Otitis with effusion

March 25, 2012 by Lobe and Dr Anthony Abela
Les otites avec effusion
Otitis with effusion is the most common chronic otologic pathology in childhood, affecting children of every age, every race and both sexes. It is caused by a build up of serous or mucous secretions behind the intact eardrum without any symptoms of acute infection (earache, fever or irritability). The changes in pressure observed are due to a tubal dysfunction (Eustachian tube). Most often, it is the repeated appearance of acute otitis media in combination with persistent otitis with effusion that calls specific attention to these cases of residual otitis. Otherwise, it is a child’s language problems or delayed learning that lead to the discovery of the otitis with effusion in question.

Epidemiology

Naturally, with current investigation methods, greater access to medical consultations and the eclectic approaches taken by doctors, otitis diagnoses are on the rise. Medical appointments made for children under the age of two have climbed over 225% in 15 years, and one third of visits involving children under one year of age led to an otitis diagnosis. The prevalence of otitis cases is largely attributable to a set of socioeconomic, genetic and environmental factors, risk factors including a family history of the condition, smoking and attending daycare. Seasonal peaks, notably in fall and winter, coincide with jumps in viral infection rates, primarily for the respiratory syncytial virus.

Physiopathology

Otitis with effusion develops as a result of Eustachian tube dysfunction in conjunction with a superinfection.

The Eustachian tube has three physiological functions:

  1. equalizing pressure on either side of the eardrum;
  2. protecting the ear from the pharynx;
  3. eliminating middle ear secretions via the tube’s mucociliary system.

Tubal dysfunction can result from an obstruction of the Eustachian tube caused by infections, allergies, enlarged adenoids, or a problem in the opening of the Eustachian tube, as can be seen in the case of a cleft palate.

In young children, the opening at the pharyngeal extremity of the Eustachian tube is affected by the cartilaginous portion of the tube, and its poor rigidity. Children’s Eustachian tubes are sloped at only a 10-degree angle, while they are positioned at a 45-degree angle in adults. Even the degree of protection afforded to the middle ear is lessened by the Eustachian tube’s small size (4.5 times smaller than an adult’s).

The empty space created in the tympanic cavity by the Eustachian tube’s obstruction and the absorption of gas is thought to lead to the formation of a sterile transudate (liquid derived from plasma); the viral or bacterial infection, for its part, produces an additional inflammatory exudate.

Clinical and diagnostic examination

Unlike acute otitis media, otitis with effusion does not produce any obvious symptoms.

Les otites avec effusion

The main symptom is a hearing lost, but children seem to live with this condition very well and rarely complain. Most evident will be the side effects of the hypoacusis, which include delayed speech development or delayed learning. Children will tend to ask people to repeat themselves, to go off on their own and to turn up the volume on the TV. They are distant and sometimes show signs of hyperactivity. Pain is simply a form of secondary infection superimposed on a pre-existing condition. The ENT examination must pay special attention to the eardrum, which has to be cleared of any visual obstruction. Otitis with effusion is characterized by the classic triad of retraction, vascular stasis and effusion. The colour of the retrotympanic fluid is highly variable, ranging from light grey to black. The examination should also look for other pathologies and pay special attention to the nasopharynx and nasal cavities.

An audiogram is an excellent complementary tool for corrobo-rating the clinical exam. Hypoacusis will range from 15 to 45 dB, with an average of 23 dB, for otitis with slight effusion.

Tympanometry is a very effec­tive technique for detecting negative retrotympanic pressure. The test does have its limits when used with young children whose external auditory canal offers a great deal of resistance.

Treating otitis with effusion

Most cases of otitis with effusion heal on their own. However, vigilance is required in order to ensure that they do progress normally. Hypoacusis of under 20 dB does not lead to any attention deficit or learning delay.

  1. Terrain treatment: Maintaining nasal hygiene through the use of a physiological serum is still the primary technique for remedying the situation. It can never be stressed enough.
  2. Medical treatment: Often disappointing, medical treatment involves testing antihistamines, decongestants or antibiotics. These treatments have not led to any improvement.
  3. Surgical treatment: Myringo­tomy is a procedure whereby a small vent tube is inserted through the eardrum to drain the middle ear in the case of a secondary infection. The tube stays in place for an average of 12 months, after which it is naturally expelled by the eardrum. Myringotomy is an easy technique which can be carried out under general or local anaesthesia.

An examination of the neighbouring structures is required to rule out any pathologies at play.

Evolution and sequelae

Normally, otitis with effusion tends to heal on its own without leaving any after-effects. Once children have reached physical and immunological maturity, they are safe from developing this condition. Our role is to help them reach that point without incurring any after-effects or eardrum impairments. It is the condition’s chronic, prolonged forms that must be feared the most, those in which damage to the eardrum impedes hearing, language skills and learning.

In conclusion, otitis with effusion is a common condition that affects a great many children and most often heals on its own. Knowing how to detect this condition is crucial if it is to be monitored effectively without falling into the overtreatment trap. Non responsive cases should be referred to an ENT specialist to avoid complications that can lead to permanent handicaps.

References:

– Bluestone, Charles. “Pediatric Otolaryngology”, vol. 1, chap. 9 and 22, W.B. Saunders.

– Scott-Brown’s. “Otolaryngology”, vol. 3 (Otology) and vol. 6 (Pediatric Otolaryngology), Butterworths.

– Paparella and Shumrick. “Otolaryngology”, vol. 2, section 4, W.B. Saunders.