What is Mastoiditis?

In this article:

• What Is mastoiditis?
• Symptoms
• When to get medical advice
• Causes
• Complications
• Diagnosis
• Risk factors
• Prevention
• References

---

What Is mastoiditis?

Mastoiditis is the inflammation of a portion of the temporal bone. This bone is located right behind the ear. It contains tiny cavities called mastoid air cells which are connected with the middle ear cavity. Normally, the air cells and middle air contain only moisturizing fluid produced by epithelial cells. But if there is an infection of the ear, the bacteria may crawl into the air cells and start mastoiditis. In rare cases the infection starts in the air cells without causing ear infection.

Acute mastoiditis represents the most common complication of an AOM, affecting 1 in 400 cases (0.24%). Its incidence is variously reported in different countries, varying in pediatric age from1.2 to 6.1 per 100,000 children aged 0-14 years, per year. 

After a significant decrease in the antibiotic era, the incidence of AM in pediatric age has consistently re-appeared in the last two decades even in developed countries. This can be attributed to a selection of resistant bacteria due to inadequate antibiotic treatments.

As children have ear infections more frequently, they are at higher risk of developing acute mastoiditis compared to adults. Mastoiditis is divided into types, and sometimes even is a part of other diseases of the ear:

1. Acute mastoiditis
2. Incipient mastoiditis 
3. Subacute otitis media referred to as subacute mastoiditis

Nowadays, the development of acute mastoiditis and progression to dangerous complications is rare. Most ear infections are caught early and treated with antibiotics, so infection does not have time to advance into the air cells. If left untreated, mastoiditis can result in life-threatening complications when bacteria gains access to the brain.

Despite advanced imaging techniques, antibiotics, and microsurgical procedures, the mortality of mastoiditis sequela in children remains 10%.

---

Symptoms

Most commonly, the patient will be a child under the age of two years presenting with:

• History of the previous ear infection
• Irritability, fussiness
• Refusal to drink or suck on pacifier and bottle
• Lethargy, unresponsiveness 
• Fever 
• Ear pulling, ear pain. 

The adult patient will typically complain of:

• Severe ear pain, neck pain
• Enlarged neck lymph nodes 
• Fever 
• Severe headache. 

When to get medical advice

Any concern for a child or adult having ear infection should be checked by a doctor. All ear infections must be properly diagnosed by a medical professional. We do not recommend to self-treat.

---

Causes

The most common bacteria in mastoiditis is Streptococcus Pneumonia. Other common pathogens include Group A beta-hemolytic streptococci, Staphylococcus aureus, Streptococcus pyogenes, and Haemophilus influenzae. 

• Incipient Mastoiditis: Infection of the mastoid air cells alone with no continuation with the middle ear cavity.
• Acute Coalescent Mastoiditis (most common presentation): Inflammation of the epithelial lining with erosion through the boney dividers of the mastoid air cells. This erosion can progress to abscess formation, which can extend further to adjacent bone or brain structures.
• Subacute Mastoiditis: Persistent middle ear infection or recurrent episodes of acute otitis media with inadequate antimicrobial therapy lead to persistent infection of the middle ear and mastoid air cells resulting in erosion of boney dividers between mastoid air cells

AM represents a severe complication of an acute (sometimes chronic) otitis media, favoured by several factors (anatomic condition of the temporal bone, age, bacterial flora, immunological defects, etc).

Given that the middle ear (ME) communicates with the mastoid area through aditus ad antrum, a mastoid involvement in infectious acute or chronic diseases of ME is very common; therefore, “otomastoiditis” is the correct definition of all otitis.

---

Complications

Complications of untreated or missed mastoiditis are dangerous and life threatening due to direct proximity of the brain and common blood vessels. Complications include:

• Meningitis 
• Intracranial abscess 
• Venous sinus thrombosis.

The most frequent complication is the subperiosteal abscess, following the progression of the inflammatory process; periostitis, the release of cytokine with osteoclasts activation and consequent decalcification and bone resorption (coalescent mastoiditis).

Other extracranial complications are due to the involvement of the nerves or blood vessels of the mastoid:

• Facial nerve pulse
• Labyrinthitis
• Internal jugular vein thrombosis
• Periphlebitis of the sigmoid or lateral sinus

In children, the mastoid bone is more pneumatized with thin bone trabeculae and the aditus ad antrum is smaller than in adult’s. So, there is a greater predisposition to the accumulation of secretion and osteitic infection.

Pediatric age is often characterized by physiological immaturity of the immune system with a peak incidence between the second and third year of life. Particularly in children, over-prescription of the non-selected antibiotics can cause growth of the resistant bacterial strains.

---

Diagnosis

Mastoiditis is a clinical diagnosis. Laboratory and imaging are used as an adjunct when you are unsure of the diagnosis or considering a complication of acute mastoiditis.

Physical examination in both children and adults will reveal postauricular erythema, tenderness, warmth, and fluctuance with protrusion of the auricle. The otoscopic examination will reveal a bulging of the posterosuperior wall of the external auditory canal and bulging of and pus behind the tympanic membrane. Often the tympanic membrane can be ruptured and draining pus. 

Clinical diagnosis is difficult. A doctor must consider following:

• A normal tympanic membrane usually, but not always, excludes acute mastoiditis.
• Although a history of recent or concurrent otitis media is common, it is not “a must” to make the diagnosis of acute mastoiditis 
• Some cases may develop rapidly during the onset of acute otitis media

If a very young child is brought to the ER with significant symptoms, a workup for sepsis and meningitis will be performed:

• Full CBC (blood cells), ESR and CRP (inflammation factors)
• Blood culture
• Lumbar puncture to see if the brain or spinal fluids are infected

Radiologic evaluation of acute mastoiditis uses CT imaging. CT scan can reveal the disruption of the bony septation in the mastoid air cells and the potential extension of the infection. In particular, CT imaging in patients with mastoiditis reveals the following:

• Fluid and/or mucosal thickening in the middle ear and mastoid condensation.
• Loss of definition of the bony septae that define mastoid air cells
• Destruction of the irregularity of the mastoid cortex
• Periosteum thickening, disruption of periosteum, or sub-periosteal abscess

---

Risk factors

Risk factors for mastoiditis include:

• Very young age less than two years old, 
• Immunocompromised patients, 
• Recurrent acute otitis media
• Ear infection not treated with antibiotics
• Incomplete pneumatization fo the mastoid bone (inborn malformation).

---

Prevention

Despite the increasingly effective antibiotic and vaccine treatments, the mastoiditis is still a worrying disease that even seems to be growing in pediatric age due to ever-increasing antibiotic resistance. The severity of the complications of acute mastoiditis suggests careful clinical observation either by the primary care or in the hospital in all cases of OMA in which the symptoms are particularly severe, especially when they occur in very young children.

As an ear infection is the leading cause of the mastoiditis, it is important to seek medical attention immediately if the child has ear pain and fever. A specialist visit to the ENT clinic is recommended if the ear infections become frequent, or persist after appropriate treatment. 

Of equal importance is a healthy lifestyle and nutrition. Immune system in a healthy person will prevent most ear infections and complications. So, many ear infections and other unusual infections in a child or adult should trigger a concern about immune deficiency. An expert Immunologist will examine the history and suggest a work-up for immune deficiency.

---

References

Acute mastoiditis in children. Cassano P, Ciprandi G, Passali D.Acta Biomed. 2020 Feb 17;91(1-S):54-59. doi: 10.23750/abm.v91i1-S.9259.PMID: 32073562 Free PMC article. Review.

Mastoiditis. Sahi D, Nguyen H, Callender KD.2021 Aug 12. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan–.PMID: 32809712 Free Books & Documents. Review.

Harrison HW, Shargorodsky J, Gopen Q. Clinical strategies for the management of acute mastoiditis in the pediatric population. Clin. Pediatr. 2010;49(2):110–115. [PubMed] [Google Scholar]

Rosenfeld RM, Kay D. Natural history of untraded otitis media Laryngoscope. 2003;113:1645–1657. [PubMed] [Google Scholar]

Quesnel M, Nguyen S, Contencin P, Manach V, Coloigner V. Acute mastoiditis in children:a retrospectivestudy of 188 patienis Int. J. Pediatr. Otolaryngol. 2010;74:1388–1392. [PubMed] [Google Scholar]

Groth A, Enoksson F, Hultcrantz M, Stalfors J, Stenfeldt K, Hermansson A. Acute mastoiditis in children aged 0-16 years. A national study of 678 cases in Sweden comparing different age groups Int. J. Pediatr. Otolaryngol. 2012;76:1494–500. [PubMed] [Google Scholar]

Ruiz Diaz AI, Del Castillo Martin F, BilbaoGaritagoitia A, Diaz Roman MJ, Garcia Miguel C, BarqueAndres C. Acute mastoiditis: an incrisingentity An. Esp.Pediatric. 2002;57:427–432. [Google Scholar]

Nussivotich M, Yoely R, Elishkevitz K, Varsano I. Acute mastoiditis in children: epidemiologic, clinical, microbiologic, and therapeutic aspects over past years. Clin. Pediatr. 2004;43:261–267. [PubMed] [Google Scholar]

Van Zuijlen DA, Schindler AG, Van Balen FA, Hoes AW. National differences in the incidence of acute mastoiditis: relationship to prescribing patterns of antibiotics for acute otitis Pediatr. Infect. Dis. J. 2001;20:1012–1013. [PubMed] [Google Scholar]