Middle ear infections in children (acute otitis media)

Middle ear infections in children (also known as acute otitis media, or AOM) are extremely common. In fact, they are the most frequent problem requiring a visit to the doctor in children under five, and the most likely cause of “earache” in this age group. About 70% of all children will see their doctor with this problem before they are two years old. This page explores the causes and treatments in detail.

Right sided middle ear infection: pus underneath a red, bulging eardrum (Michael Hawke MD) 

Right sided middle ear infection: pus underneath a red, bulging eardrum (Michael Hawke MD) 

What is the middle ear?

Our ears are divided into three parts: the outer ear (the ear itself and the ear canal), the middle ear (eardrum and the chamber underneath it) and the inner ear (which houses the hearing and balance organs, within the bone of the skull). This is all explained in the NHS Choices video about glue ear, shown here.

The middle ear is a sealed chamber, separated from the environment by the eardrum. This, together with three little bones in the middle ear (hammer, anvil and stirrup- shown in the video), amplifies sound arriving to the hearing organ in the inner ear. The eardrum also keeps out water, bacteria and viruses from the outside. The middle ear chamber is connected to the back of the nose (on each side) by a muscle and cartilage tube: the Eustachian Tube. This allows a little squirt of air to pass up from the back of the nose to the middle ear chamber each time we yawn or swallow, refreshing the air in the middle ear which is slowly used up with time. We notice our ears “popping” when flying or diving under water, but in fact this happens all the time in normal circumstances, usually without us realising.

 

How do middle ear infections happen?

Problems can occur when the ears do not “pop” properly, stopping the air in the middle ear chamber from being refreshed, and causing the eardrum to be slowly sucked in (giving the feeling of a blocked ear). Although the ear canal and eardrum are covered in skin, the lining of the middle ear chamber is covered with a mucus-producing lining, the same as that in the nose and throat. If not enough air reaches the middle ear because the ears will not “pop”, then the lining becomes unhealthy, producing thick mucus, like children’s glue. This is known as glue ear, reducing conduction of sound through the middle ear and therefore reduced hearing. This is all explained in the NHS choices video, also available here.

At the same time, when children have colds, their noses and throats become red and raw, causing more mucus to be produced (eg a runny nose). These are called upper respiratory tract infections, or URTIs. Young children may have 10-15 of these per year. The middle ear lining, like that of the nose and throat, also becomes inflamed and produces more mucus and pus. Pressure of mucus and pus builds up behind the eardrum, causing the pain and fevers characteristic of children’s earache.

 

Who is affected?

Large studies, including one from Pittsburgh in the USA, show that middle ear infections are commonest in young children, particularly those under two. They can also occur in older children and adults, but are far less common with age. In fact, other causes of “earache” will be more likely in older children and adults (eg ear canal infections or jaw joint pain).

Aside from having immature immune systems, young children’s Eustachian Tubes may not work very effectively, meaning that the ears fail to “pop” and middle ear fluid and infections are therefore more likely than in older children. The Eustachian Tubes in young children are also quite short, and so viruses and bacteria may find their way up from the nose into the middle ear more easily.

Apart from young age, other risk factors are:

  • Winter months: the cough and colds season
  • Male sex: boys are slightly more often affected than girls
  • Family history
  • Living in cities, rather than in the country
  • Going to nursery with a number of other children
  • Ethnicity: in the USA studies, Native American children were most commonly affected, then white children, with Afro-Caribbean children least affected.
  • Low birth weight or prematurity
  • Poor immunity: this may be more evident in children who have had lots of other infections (chest, urinary etc). Please make sure your child’s immunisations are up to date, particularly the Pneumococcal Conjugate Vaccine (PCV).
  • Regular use of a dummy (pacifier).
  • Bottle feeding (rather than breast feeding).
  • Reflux (burping up feeds)
  • Additionally, the studies suggest that children who have their first middle ear infection when they are very young (3-4 months old) are more likely to have repeated middle ear infections.

 

 

What are the symptoms?

Although we naturally expect that children with middle ear infections should have ear pain and fever, the presentation may be more subtle, especially in infants. They can, for example, be confused with teething.

Things to look out for are:

  • Obvious ear pain in older children, or irritability +/- tugging at the ears in little ones.
  • Fever (more likely in older children); infants may not have a temperature at all.
  • Reduced appetite.
  • Nausea and/or vomiting.
  • Ear discharge (if pressure of pus causes the eardrum to burst). This may be the first sign of an ear infection, particularly in infants.
  • Hearing loss (older children and adults may complain of this, as the middle ear is full of fluid).
  • Other signs of a cold (runny nose, sore throat, cough).

 

 

How is a middle ear infection diagnosed?

This is based on parents’ history of symptoms (above) and signs which a doctors looks for. These include a temperature, a red and/or bulging eardrum and discharge of pus in the ear canal. Milder cases are in fact quite difficult to diagnose, particularly in little children with small, waxy ear canals. It is therefore common and reasonable that in many cases parents are asked to try simple measures for 24-48 hours before coming back to see their doctor for re-assessment. 

 

Is the infection caused by viruses or bacteria?

Most upper respiratory infections are caused by “cold” viruses. These cause runny noses, sore throats and middle ear inflammation and infection. It therefore follows that viruses are the basis for most middle ear infections.

However, bacteria can then also colonise the already infected areas, as the lining of the middle ear has been weakened by the virus. Mucus sits in the middle ear and cannot clear properly, making it an ideal place for the bacteria to live. The most common bacteria groups are Streptococcus pneumoniae (pneumococcus), Haemophilus influenzae and Moraxella catarrhalis- all of these are usually treatable with amoxicillin or similar antibiotics (please see below).

 

How are middle ear infections treated?

Much of the treatment for middle ear infections is supportive. In fact, many cases of middle ear infections can be managed by parents at home, without needing to see the GP for additional medicines.

Supportive measures

Children should be encouraged to drink plenty of fluids, so their mouths are moist and their urine is clear and plentiful (wet nappies).

Pain relief is also essential. Ibuprofen (Nurofen or Calpofen) has been shown to be even more effective than paracetamol (Calpol) for ear pain. Both ibuprofen and paracetamol can be used regularly together, four times a day. They will help reduce both pain and fever. Further information on how to manage a child with a fever is available through NICE by clicking here.

Antibiotics

 

Many parents ask whether antibiotics are necessary. Various studies have looked into this, showing that antibiotics, when averaged out over hundreds of cases, generally reduce the overall duration and severity of middle ear infections a little. In reality, on an individual case-by-case basis, some entirely viral cases will not benefit at all, while others with bacterial infection will benefit from antibiotics. The evidence also suggests a reduction in complications of middle ear infections, such as mastoiditis (please see below) in children who have received prompt antibiotic treatment.

It is difficult to know whether each infection is mainly viral or bacterial. Higher temperatures (more than 39°C) and a sicker child generally suggest bacterial infection, but this is not always the case. 

For these reasons, NICE has released suggestions for antibiotic prescribing in middle ear infections. These are available here. The American Academy of Pediatrics has also released very similar guidelines, and can be downloaded here.

  • Antibiotics are recommended for immediate treatment if children are very unwell, or if they have other major illnesses (heart, lung, liver, kidney problems, etc.), or if symptoms have lasted for four or more days without improvement.

 

  • It is also reasonable to start antibiotics if the child is aged three months younger, if there is a hole in the eardrum(s) with discharging pus, or in children under two years with ear infections on both sides.

 

  • In other cases (eg older children with only one affected ear), many doctors should generally delay starting antibiotics, seeing children after 24-48 hours to see if they have improved or not. Simple measures and pain relief are continued during this time.

 

 

Which antibiotic should be used?

According to the medical evidence, The American Academy of Pediatrics and NICE in the UK both recommend amoxicillin (from the penicillin family) as the first line antibiotic. The Centre for Disease Control in the USA recommends a high dose of amoxicillin, because some bacteria are developing resistance: 80-90 milligrams per kilogram in total per day. Clarithromycin or erythromycin are used instead if the child is allergic to penicillin.

More resistant cases, particularly those who have already had amoxicillin with no improvement, may benefit from other antibiotics such as co-amoxiclav (Augmentin) (which contains amoxicillin and clavulanic acid to offer cover against resistant bacteria). Ceftriaxone and other similar antibiotics may also be used.

 

Duration of treatment

There is no consensus about how long antibiotics should be used for. One week is usually reasonable, sometimes more, and improvement should be expected within 48-72 hours of starting antibiotics. If this is not the case, other antibiotics should be considered, or even admission to hospital if symptoms are worse and severe.

 

Severe cases and complications

Most cases of middle ear infections settle with simple measures, sometimes requiring antibiotics from your GP. In cases where children are particularly unwell, with very high fevers or dehydration, then hospital admission may be required, for drip (intravenous) antibiotics and fluids. This is particularly the case for very young children.

Middle ear infections often result in a burst eardrum (perforation) as a result of pus pres sure underneath it. This leads to pus discharge from the ear, which tends to relieve the pressure-associated ear pain. The discharge may take several days to settle. You can clear away the excess using a baby wipe, but nothing should be inserted into the ear. The ears should also be kept dry at bath time (please see the water precautions section) until 1-2 weeks after the discharge has settled, to allow the eardrum to heal. As well as oral antibiotics, it is also often useful to use antibiotic ear drops in these circumstances. Details of the correct antibiotic drops to use and how to put them into the child’s ear are available in the relevant patient information sections (please click here).

In most cases, the eardrum will heal up on its own if the ears are kept dry. In some cases, however, a small eardrum hole (or perforation) may persist. If it does not eventually heal up on its own, a perforation can usually be easily repaired when the child is older. It is worth keeping the ears dry while the perforation persists. After the eardrum heals, there may be a white patch at the healed site. This rarely causes any problems, but it might be noticed by doctors in the future. This is called tympanosclerosis.

 

Other problems can also occur after middle ear infections. Fluid may persist in the middle ear for some time (glue ear) even after the pus has cleared, causing reduced hearing. This is all explained in the glue ear section.

Rarely, hearing may be affected as a result of damage to the little bones in the middle ear which normally amplify the hearing, or because of scarring in the middle ear, or even because of injury to the hearing organ of the inner ear. These scenarios are very rare, considering how many children are affected by middle ear infections.

Infection may also spread to the spongy bone of the skull above and behind the ear, and may form a collection of pus (abscess) in this area. This is called mastoiditis. This was once very common, but is now rare (with better healthcare and antibiotics). Pus in mastoiditis may settle with high dose drip (intravenous) antibiotics in hospital, or may require a drainage operation to release it (simple mastoidectomy).

Middle ear infections may lead to other dangerous complications, including meningitis- although this is a rare consequence.

If your child is very unwell, has a very high fever, is vomiting repeatedly or is unable to eat or drink, is lethargic or confused, has a dislike for light, has neck stiffness or a non-blanching rash, then please seek emergency medical attention.

 

What if the middle ear infections are repeated (recurrent acute otitis media)?

 

Repeated middle ear infections are common. Half of under twos who have a bout of middle ear infection will have another within the next six months. According to the American Academy of Pediatrics, middle ear infections are said to be recurrent if there are three or more episodes in six months, or four in the past year (with at least one of these in the past six months).

Risk factors for recurrent AOM are:

  • First infection under three months of age
  • Persistent previous middle ear infections (more than 10 days)
  • Winter months
  • Male gender
  • Passive smoking

 

 

Treatment of recurrent middle ear infections

Treatment of recurrent AOM should address each episode as above: supportive measures, pain relief, fluids and perhaps antibiotics.

We should always bear in mind that the situation is likely to improve naturally as the child gets older, even without any treatment.

The American Academy of Pediatrics suggests that reversible causes should be looked at first (no smoking in the household, immunisations should be up-to-date, dummies should be avoided and breast feeding should be encouraged until the age of six months etc).

However, if infections are frequent and severe and affect quality of life, then some ways of trying to reduce the frequency and severity of further attacks can also be used. These are known as preventative or prophylactic treatments.

 

Long-term, low-dose antibiotics

It is sometimes reasonable to consider antibiotics in low doses, taken for weeks or months at a time. This reduces numbers of bacteria in the nose and throat, and therefore hopefully reduces the number of middle ear infections.

A few studies (combined in a recent UK Cochrane Review of antibiotics for recurrent AOM) have shown that this sort of longer-term antibiotic treatment tends to halve the number of middle ear infections per year, for the average child, and is especially beneficial in severely-affected children with six or more episodes per year.

The benefit only lasts for as long as the antibiotics are used, and the overall evidence is not very strong. Therefore, while routine use of preventative low-dose antibiotics for repeated middle ear infections is not recommended by the American Academy of Pediatrics, there are still instances where they may be useful (small children, very frequent infections etc), in conjunction with the measures above.

Different types of antibiotics may be used, none appearing to be much more effective than the others. I tend to use azithromycin, which quickly reaches high concentrations in the tissues, but has a low risk of side effects. This is given at a dose of 10mg per kilogram of the child’s weight, once daily on Monday, Tuesday and Wednesday (or any three consecutive days) of a given week, followed by 11 days off. This cycle is repeated every two weeks for six to eight weeks. This may help children through difficult periods of repeated ear infections, eg over the winter months. Other alternatives include trimethoprim (given nightly), amoxicillin or co-amoxiclav.

 

Grommets

Where infections are repeated, and where medical treatments have been tried without success, it may be worth considering inserting grommets. These are fully described in their own section (please click here to open).

Although many studies have looked at the benefits of grommets for glue ear, few have looked at the role of grommets purely for middle ear infections. The Cochrane Review of the best evidence suggests some benefits with grommets, in terms of reducing the frequency of middle ear infections and improving quality of life. The American Academy of Pediatrics supports the use of grommets if the middle ear infections are recurrent (three in six months or four in a year- with at least one in the previous six months).

A short anaesthetic is required for grommet insertions, and they may produce problems of their own, particularly repeated discharge of mucus and/or pus. They should therefore be used only after considering the options in the case of the individual child, and balanced against medical treatments and watchful waiting.

 

Other preventative treatments: no proven benefits

Although removal of the adenoids (adenoidectomy) has proven benefits when treating glue ear, often in conjunction with grommets, studies show that adenoidectomy is not generally beneficial in cases of recurrent middle ear infections- unless they are associated with problematic glue ear or problematic nasal obstruction. 

As with glue ear, the American Academy of Pediatrics and NICE feel that the evidence is more limited for other treatments, including other medications and complimentary medicines. These groups therefore do not recommend their use for middle ear infections, based on a lack of robust evidence.

 

Summary

  • Middle ear infections (acute otitis media) are very common in young children, but reduce in frequency as children get older.

 

  • Supportive measures (fluids, rest and regular pain relief) are essential in all cases.

 

  • Antibiotics are sometimes required, particularly in very young children with both ears affected, but these should be used in addition to supportive measures.

 

  • Amoxicillin (ideally at a high dose) is the first line antibiotic of choice, with clarithromycin or erythromycin if the child is allergic to penicillins. This should allow improvement within 48-72 hours; if not, please see your doctor again.

 

  • Recurrent middle ear infections are also common. These can be treated in the same way, as and when they occur.

 

  • Preventative measures (vaccinations up-to-date, lifestyle, low-dose long-term antibiotics or grommets) may also be used.

 

  • Severe cases of middle ear infections, or those with complications, may require hospital admission.

 

 

If your child has a very high fever, is unable to eat or drink, is lethargic or confused, has a dislike for light, has neck stiffness or a non-blanching rash, then please seek emergency medical attention.