Suppurative labyrinthitis is a diffuse suppurative infection of the labyrinth caused by the invasion of pyogenic bacteria into the inner ear. This condition results in the destruction of the inner ear's terminal organs and complete loss of function. The infection may further spread intracranially, leading to intracranial complications.
Suppurative labyrinthitis often arises from the spread of middle ear infections or as a progression from serous labyrinthitis. Cases secondary to acute suppurative otitis media or mastoiditis are frequently caused by Streptococcus pneumoniae (type III) or hemolytic streptococci.
Pathology
Before the development of suppuration, serous exudation occurs and is followed by infiltration of white blood cells and fibrinous exudation throughout the labyrinth. This leads to suppurative changes, pus accumulation, tissue necrosis, and granulation formation. If the inflammation is not controlled, the infection may spread intracranially via the endolymphatic duct, cochlear aqueduct, or internal auditory canal. If the infection is incompletely controlled and suppurative foci remain in the inner ear, the condition may transition into a chronic phase, known as latent or concealed labyrinthitis. With prompt treatment and adequate drainage, the disease may resolve with localized proliferation of fibrous connective tissue and new bone formation.
Clinical manifestations
Severe, persistent vertigo is accompanied by episodes of intense nausea and emesis, lasting 1 - 4 weeks. In the early stages, nystagmus is directed toward the affected side due to vestibular stimulation, but it soon reverses with great intensity, with the fast phase directed toward the healthy side. The body tends to tilt toward the affected side. If the fast phase of nystagmus shifts back to the affected side, intracranial complications should be suspected. After the acute phase, peripheral vestibular function does not recover. However, central vestibular compensation gradually reduces vertigo, and balance function is restored over time.
Rapid and complete loss of hearing is often accompanied by persistent high-frequency tinnitus.
Body temperature is generally not elevated. However, fever, headache, and meningeal irritation signs suggest the possibility of intracranial complications.
The fistula test is negative due to destruction of the labyrinth. Vestibular function tests indicate complete loss of vestibular function on the affected side.
Treatment
High-dose antibiotics can be administered to control the infection.
Mastoidectomy can be performed to remove pathological lesions in the middle ear, mastoid, and inner ear, ensuring adequate drainage.
Water and electrolyte balance should be maintained through appropriate fluid therapy.