These include:
1) Invasive or "malignant" otitis externa
2) Rhinocerebral mucormycosis
3) Emphysematous infections (most commonly, pyelonephritis and cholecystitis)
4) Synergistic necrotizing cellulitis
5) Pyogenic liver abscess
Some key points to remember about invasive otitis externa:
- Most commonly diagnosed in the elderly diabetic population.
- Most commonly diagnosed in the elderly diabetic population.
- It is almost always caused by Pseudomonas aeruginosa (around 95%).
- Presents classically with otalgia and otorrhea.
- Osteomyelitis of the temporal bone can lead to palsies of cranial nerves VI, VII, IX, X, XI, XII.
- If left untreated, the infection can progress to meningitis and brain abscess formation.
- The diagnosis is made on the basis of findings on imaging (see below).
- Antimicrobial therapy targets the culprit pathogen, typically for 6-8 weeks.
Bone Scan demonstrating the "ear muff sign" of the right mastoid region.
CT head demonstrating bony erosion of the anterior wall of the right mastoid air cells.
- Presents classically with otalgia and otorrhea.
- Osteomyelitis of the temporal bone can lead to palsies of cranial nerves VI, VII, IX, X, XI, XII.
- If left untreated, the infection can progress to meningitis and brain abscess formation.
- The diagnosis is made on the basis of findings on imaging (see below).
- Antimicrobial therapy targets the culprit pathogen, typically for 6-8 weeks.
