Temporal bone findings in Cogan's syndrome

Secondary autoimmune immune ear disease (AIED): a systematic review and meta-analysis on vestibular manifestations of systemic autoimmune and inflammatory disorders

Secondary autoimmune inner ear disease (AIED) is often bilateral and asymmetric in patients presenting with audiovestibular symptoms due to a systemic autoimmune disease. This systematic review and meta-analysis are aimed at identifying and highlighting patterns in prevalence of vestibular dysfunction, symptom presentation, and diagnostic methods in extant literature by combining clinical context from case reports with quantitative analyses from cohort studies. Screening of articles by title, abstract, and full text was completed by four reviewers (K.Z., A.L., S.C., and S.J.). In this study, we grouped secondary AIED and systemic autoimmune diseases by pathophysiologic mechanism: (1) connective tissue disease (CTD), (2) vasculitides (VAS), (3) systemic inflammatory disorders (SID), and (4) other immune-mediated disorders (OIMD). The search for AIED disease identified 120 articles (cohorts and case reports) that met the final inclusion criteria. All 120 were included in the qualitative review, and 54 articles were included for meta-analysis. Of these 54 articles, 22 included a control group (CwC). Ninety individual cases or patient presentations from 66 articles were included for analysis in addition to the 54 cohort articles. Secondary AIED does not have a diagnostic algorithm for managing vestibular symptoms. The management of audiovestibular symptoms requires close collaboration between otolaryngologists and rheumatologists to preserve end-organ function of the ear. To improve our ability to understand the impact on the vestibular system, vestibular clinicians need to develop a standardized reporting method. Clinical presentation should frequently be paired with vestibular testing to contextually investigate symptom severity and provide higher quality care.

Otologic manifestations of Susac syndrome

Susac syndrome, a rare autoimmune disorder first described as a classic triad (encephalopathy, branch retinal artery occlusion, and sensorineural hearing loss) in 1979 by renowned physician John O. Susac, has been an advancing area of clinical interest and scientific research over the last several decades. This comprehensive review aims to succinctly highlight the breadth and detail of this enigmatic disease, with a primary focus on otologic manifestations. Topics discussed include epidemiology, pathophysiology, clinical manifestations, differential diagnoses, classification schema, laboratory investigations, characteristic audiometric findings, high-yield radiographic imaging, temporal bone histopathology, treatment strategies and overall prognosis.

Histopathology of the Human Inner Ear in the Cogan Syndrome with Cochlear Implantation

The Cogan syndrome is a rare disorder characterized by nonsyphilitic interstitial keratitis and audiovestibular symptoms. Profound sensorineural hearing loss has been reported in approximately half of the patients with the Cogan syndrome resulting in candidacy for cochlear implantation in some patients. The current study is the first histopathologic report on the temporal bones of a patient with the Cogan syndrome who during life underwent bilateral cochlear implantation. Preoperative MRI revealed tissue with high density in the basal turns of both cochleae and both vestibular systems consistent with fibrous tissue due to labyrinthitis. Histopathology demonstrated fibrous tissue and new bone formation within the cochlea and vestibular apparatus, worse on the right. Severe degeneration of the vestibular end organs and new bone formation in the labyrinth were seen more on the right than on the left. Although severe bilateral degeneration of the spiral ganglion neurons was seen, especially on the right, the postoperative word discrimination score was between 50 and 60% bilaterally. Impedance measures were generally higher in the right ear, possibly related to more fibrous tissue and new bone found in the scala tympani on the right side.

Histopathology of the Inner Ear in a Case With Recent Onset of Cogan’s Syndrome

The association of sensorineural hearing loss and vertigo with inflammatory eye disease, usually interstitial keratitis, has been called Cogan’s syndrome. The pathogenesis of Cogan’s syndrome is unknown, but it has been assumed to be an immune mediated disorder with vasculitis. The histopathology of the inner ear in Cogan’s syndrome has been described in 6 case reports. Although common pathologic findings in these reports include degeneration of the auditory and vestibular neuroepithelium, endolymphatic hydrops, fibrosis, and new bone formation, direct pathologic evidence of a vasculitis has not been published. A possible reason for this failure to identify vasculitis was a substantial delay (range, 4-40 years) between the onset of symptoms and examination of the otopathology. In the current case report, the patient had both auditory and vestibular symptoms and interstitial keratitis with a time delay of only 2 to 4 weeks between symptoms and death. Evidence of a vasculitis as a possible underlying etiology included H&E histopathology and anti-CD45 immunostaining of vessels both in the auditory and vestibular systems, supporting the hypothesis of a vasculitis as a mechanism in this disorder.

Corticosteroid pharmacokinetics in the inner ear fluids: an animal study followed by clinical application

OBJECTIVE

Autoimmune disease (e.g., Cogan syndrome) and other inflammatory inner ear diseases may ravage the labyrinth if not treated aggressively with antiinflammatory medication. Corticosteroids are the mainstay of treatment, yet, partly because of the existence of the blood-labyrinthine barrier, the ideal drug, dose, and route of administration are currently unknown.

STUDY DESIGN

In the present study, we established cochlear fluid pharmacokinetic profiles of hydrocortisone, methylprednisolone, and dexamethasone in the guinea pig following oral, intravenous, and topical (intratympanic) administration. High-performance liquid chromatography was used to determine the drug concentrations, and comparisons were made with simultaneous pharmacokinetic profiles from blood and cerebrospinal fluid.

RESULTS

Our findings demonstrated a much higher penetration of all three drugs into the cochlear fluids following topical application as compared with systemic administration, with methylprednisolone showing the best profile.

DISCUSSION

The results suggested that intratympanic administration of corticosteroids might be more efficacious while avoiding high blood levels and therefore the deleterious side effects of systemic use.

CLINICAL APPLICATION

Thirty-seven patients with various inner ear disorders causing sensorineural hearing loss were subsequently treated using intratympanic corticosteroids, 20 with dexamethasone, and 17 with methlyprednisolone. Patients with immune-mediated hearing losses showed the best results, with notable improvement also seen in several cases of a "sudden deafness." No benefit was seen in patients with cochlear hydrops or those with sudden deterioration of a preexisting hearing loss. Three patients developed a transient otitis media related to the treatments, easily controlled with antibiotics. There were no cases of treatment-induced hearing loss and no permanent tympanic membrane perforations.

CONCLUSIONS

Overall injection of intratympanic corticosteroids for the treatment of hearing loss in inner ear disorders appears to be both safe and highly effective for certain disorders. The concept of this technique is supported by animal experimental data. The findings from the present study warrant further clinical application and experimental investigation.