Purpose: Mondini dysplasia is a rare congenital inner ear malformation that presents with abnormal cochlear development with accompanied vestibular dilation and vestibular aqueduct enlargement. This dysfunctional anatomy provides the potential for sensorineural hearing deficits, cerebrospinal fluid leaks, and severe cases of recurrent meningitis.
Methods: We present the case of a child with Mondini dysplasia who presented with unilateral hearing loss and cerebrospinal fluid (CSF) otorrhea that was surgically repaired through a combined middle fossa/transmeatal middle ear approach to alleviate any recurrence of infection and cerebrospinal fluid otorrhea.
Results: Postoperatively, the patient remained neurologically stable without any further CSF leakage. CSF cultures revealed a Pseudomonas aeruginosa infection, a rare occurrence within the context of Mondini dysplasia. Retrograde bacterial spread from the external ear canal into the CSF space has been theorized as the possible pathogenesis of the resulting meningitis. The patient was successfully treated with intravenous antibiotics without any neurologic complications.
Conclusions: Although Mondini dysplasia is a rare malformation, the life-threatening sequelae of meningitis that can result from the dysfunctional anatomy makes it a condition that requires elevated clinical vigilance, especially when considering children with hearing loss associated with recurrent meningitis, otorrhea, or rhinorrhea.