What Is Mastoiditis?

Overview

Mastoiditis is a bacterial infection of the mastoid process, which is a part of the temporal bone that is found behind the ear. This infection may result from an untreated middle ear infection, which can extend to the mastoid process. Despite being a rare condition, mastoiditis is more frequent in children. To further understand the causes, typical progression, and warning signs of mastoiditis, keep reading.¹

The middle ear is connected to a bone called the mastoid apophysis by structures called the mastoid air cells. If these mastoid air cells become inflamed, also known as otomastoiditis, the infection can spread to the mastoid bone. Mastoiditis tends to be acute (short-lasting), but may potentially be chronic (longer-lasting).

The mastoid process is part of the temporal bone, which is seen on the sides of the head and at the base of the skull. It is linked to the middle ear through a small opening known as the mastoid antrum. Its role is to store air that can compensate for pressure fluctuations in the middle ear and the auditory tube. Mastoiditis is typically a complication of acute middle ear infections, which is accompanied by pus production.^{1, 2, 3}

Causes of mastoiditis

Mastoiditis is inflammation of the mastoid process that is often brought on by a bacterial infection. It is most frequently a result of a middle ear infection that has been left untreated or has been treated inadequately. It is possible for middle ear infections to progress to mastoiditis if they are not treated right away, or if they affect the mastoid air cells.⁴

Middle ear infections typically occur when bacteria enter the middle ear through the eustachian tube, which is connected to the throat and helps regulate air pressure. During respiratory infections, bacteria can travel through the eustachian tube and infect the middle ear. When middle ear infections go untreated or do not respond well to treatment, the bacteria can spread to the mastoid air cells, air-filled spaces within the mastoid bone located behind the ear. This results in inflammation and infection in the mastoid region, which is called mastoiditis.^{5, 6}

The proximity of the mastoid process to the middle ear facilitates the spread of bacteria, allowing the infection to progress from the middle ear. This leads to the accumulation of pus in this region, causing pain and discomfort. The bacteria that causes this condition typically resides in the upper respiratory tract, and then enters the middle ear through the eustachian tube to cause infection. Furthermore, a direct injury or surgery at the site of the mastoid process can also cause mastoiditis. Bacteria that most often cause mastoiditis include:^{7, 8, 9}

• Streptococcus pneumoniae
• Staphylococcus aureus
• Streptococcus pyogenes
• Haemophilus influenzae

Symptoms of mastoiditis

Mastoiditis can be difficult to diagnose because the symptoms a patient presents with can be similar to those observed in ear infections. Depending on the severity of the infection, different symptoms of mastoiditis may be present, such as:

• Ear pain
• Redness and swelling behind the ear
• Drainage of pus from the ear
• Fever
• Headache
• Irritability
• Neck pain and stiffness
• Imbalance or dizziness
• Hearing problems ^{1, 10}

If you notice any signs or symptoms that indicate you may have mastoiditis, you should contact your doctor as soon as possible for a comprehensive examination to help stop the spread of the infection and lower the chance of developing serious problems.

Diagnosis of mastoiditis

Mastoiditis should be diagnosed as soon as possible by an ear, nose, and throat (ENT) doctor. Diagnosis involves a thorough evaluation of the patient's medical history and symptoms, followed by a meticulous physical examination focusing on the area behind the ear and the ear canal. 

A medical professional could also require additional testing to determine the extent of mastoiditis. Imaging technology (most frequently CT scans) and blood tests can be used to look for complications and assess the severity of mastoiditis. When pus is present, it can be studied using microbiology tests to determine the bacteria that is causing the infection. In more serious cases, a lumbar puncture may be required to collect cerebrospinal fluid for microbiological analysis, when it is suspected that infection may have spread to the brain or meninges (membranes that cover and protect the brain and spinal cord).^{8, 11}

This comprehensive diagnostic approach allows specialists to swiftly initiate appropriate treatment and reduce the risk of complications.²

Complications associated with mastoiditis

Mastoiditis has the potential to be fatal if not diagnosed and treated promptly, requiring immediate medical attention. Some of the side effects of mastoiditis include:

• Facial nerve damage, which can cause facial paralysis
• Intracranial complications, such as meningitis or brain abscess
• Labyrinthitis, which is caused by an infection of the inner ear canal and can cause vertigo
• Bone erosion, which can permanently alter the structure of the head and neck
• Hearing loss, brought on by damage to the middle ear and inner ear
• Cholesteatoma development, which is an abnormal skin growth in the middle ear that develops as a result of chronic or recurring mastoiditis 
• Sepsis, which is a generalised infection that can spread all over the body ¹ 

Treatment and management

ENT doctors ought to establish the best course of treatment for mastoiditis. This typically requires hospitalisation, depending on the infection's severity and whether there are any complications. Antibiotics and painkillers are given to reduce infection and symptoms of inflammation. If antibiotics are insufficient to treat the infection, it might be necessary to drain fluid from the mastoid process (if there is an abscess) or to undergo surgery. A procedure called a mastoidectomy is performed to remove pus-filled tissue.^{2, 11, 12}

To properly monitor the healing process and ensure successful recovery from mastoiditis, patients are actively followed up by healthcare professionals after treatment. This entails routine examinations and evaluations to track the patient's health and look for any signs of a potential recurrence. The medical professionals may conduct extensive tests, examine imaging results, and run the required tests during these follow-up appointments to ensure there are no problems or residual infections. 

How can you prevent mastoiditis?

As mastoiditis often develops as a complication of middle ear infections, precautions need to be taken to prevent middle ear infections. Aside from ensuring that ear infections are properly treated, that medical care is sought promptly, and that antibiotics are taken according to your doctor’s guidance, some other preventive measures include:

• Maintaining ear hygiene and cleanliness
• Reducing respiratory tract infections
• Avoid getting water inside the ears as this can lead to a swimmer's ear

When these preventive measures are followed, mastoiditis and other complications related to ear infections are less likely to occur.

Summary

Mastoiditis is a bacterial infection that causes inflammation of the mastoid process. It is a complication of untreated middle ear infections, most commonly seen in children. The infection occurs due to bacteria from your upper respiratory tract entering the middle ear through the eustachian tube. Symptoms may include ear pain, redness, swelling, pus drainage, fever, headache, and dizziness. 

Diagnosis involves a doctor taking your clinical history and performing a physical examination. Imaging studies and microbiology tests may also be required. If left untreated, mastoiditis can lead to severe complications, like facial nerve damage and sepsis. Treatment includes antibiotics, pain relief, and surgery to drain pus-filled tissue. Preventive measures involve proper treatment of middle ear infections, maintaining ear hygiene, reducing respiratory infections, and preventing water from entering the ears.