Bullous external otitis and bullous myringitis
Bullous external otitis presents as sudden, severe otalgia followed by bloody or serosanguinous drainage from the EAC. Compared with bullous
myringitis, no history of upper respiratory infection or relief of pain following the appearance of drainage is noted in bullous external otitis. Although
cultures have yielded P. aeruginosa and Mycoplasma pneumoniae, the causative agent is thought most often to be viral.17,35
Otoscopy reveals bluish-red hemorrhagic bullae covering the skin of the osseous EAC in bullous external otitis. The vesicles involve the tympanic
membrane in bullous myringitis (Plate 17, F). A middle-ear effusion may be present with bullous myringitis and abates after 2 to 3 weeks.
Management involves analgesics, steroids, and topical and oral antibiotics. The severity of pain may warrant the use of narcotics or decompression
of tense bullae with a sterile straight needle. Topical analgesics may be useful when combined with antibiotic drops. Ampicillin,
trimethoprim–sulfamethoxazole, or erythromycin provides adequate coverage for preventing or treating bacterial superinfection.