A 2-year-old boy is brought to the clinic by his parents due to worsening right ear pain. His mother states, "He started tugging at his ear 3 days ago and had a fever, but I could not take time off from work to bring him in." This morning, the pain increased, and his father notes that "his ear seems more prominent, like it's sticking out from his head." The patient has been less active than normal but has had no vomiting, diarrhea, or rash. He had an episode of acute otitis media 2 months ago that resolved with oral antibiotics. Immunizations are up to date, and he takes no daily medications. Temperature is 40 C (104 F), blood pressure is 100/40 mm Hg, pulse is 132/min, and respirations are 30/min. Examination shows a tired, irritable boy who screams with any attempt to examine his ear. Swelling, erythema, and tenderness to palpation are noted posterior to the right ear. Otoscopy reveals an erythematous and bulging tympanic membrane with loss of normal landmarks and light reflex.
Involvement of which of the following structures is most likely responsible for this patient's presentation?

Question

A 2-year-old boy is brought to the clinic by his parents due to worsening right ear pain.  His mother states, "He started tugging at his ear 3 days ago and had a fever, but I could not take time off from work to bring him in."  This morning, the pain increased, and his father notes that "his ear seems more prominent, like it's sticking out from his head."  The patient has been less active than normal but has had no vomiting, diarrhea, or rash.  He had an episode of acute otitis media 2 months ago that resolved with oral antibiotics.  Immunizations are up to date, and he takes no daily medications.  Temperature is 40 C (104 F), blood pressure is 100/40 mm Hg, pulse is 132/min, and respirations are 30/min.  Examination shows a tired, irritable boy who screams with any attempt to examine his ear.  Swelling, erythema, and tenderness to palpation are noted posterior to the right ear.  Otoscopy reveals an erythematous and bulging tympanic membrane with loss of normal landmarks and light reflex. 
Involvement of which of the following structures is most likely responsible for this patient's presentation?

Quizplus · Accepted Answer

Explanation: 11ec2b69_c12c_50b9_8f63_a561165c3252_MD0005_00 This febrile child with a bulging tympanic membrane who has mastoid tenderness and displacement of the external ear likely has acute mastoiditis, the most common suppurative complication of acute otitis media (AOM). The mastoid air cells are in continuity with the middle ear, allowing spread of the infection. In addition to the symptoms of fever and ear pain seen in AOM, infection of the mastoid causes erythema and tender swelling, which can result in outward and/or vertical displacement of the auricle. The tympanic membrane may show evidence of AOM (eg, erythema, bulging, perforation) or may not be visible due to swelling of the external auditory canal. acute otitis media (AOM) As with AOM, mastoiditis is most commonly seen in children age ≤2 and is commonly caused by Streptococcus pneumoniae, Streptococcus pyogenes, and Staphylococcus aureus. Pseudomonas aeruginosa has occasionally been implicated, especially in patients with recurrent infections or recent antibiotic use. (Choices A and E) Intracranial extension (eg, epidural space, meninges, brain) of AOM can occur and cause meningitis, an epidural abscess, lateral sinus thrombosis, or a brain abscess. However, in addition to the symptoms of fever and otalgia common in AOM, patients with intracranial extension typically have signs of meningeal irritation and increased intracranial pressure (eg, vomiting). meningeal irritation (Choice B) Infection of the external auditory canal results in otitis externa, which is characterized by pain, erythema, and edema of the external auditory canal, not the mastoid process. It is not typically seen as a complication of AOM, and the tympanic membrane would not be bulging or erythematous. (Choice C) Suppurative labyrinthitis can occur as a complication of AOM due to spread of the infection to the bony labyrinth of the inner ear. In addition to symptoms of fever and otalgia due to AOM, patients with suppurative labyrinthitis typically have severe vertigo with nystagmus, nausea and vomiting, and significant hearing loss. Educational objective: Acute mastoiditis, a complication of acute otitis media (AOM), is caused by spread of the infection from the middle ear space to the mastoid air cells. In addition to the fever and otalgia often present in AOM, patients also have mastoid inflammation, resulting in tenderness of the mastoid process and displacement of the auricle.

A 2-Year-Old Boy Is Brought to the Clinic by His