Résumé
To assess the value of the multifrequency tympanometry [MFT] in rheumatoid arthritis [RA] patients. 56 patients with RA, and 54 well-matched controls. MFT was used to measure admittance, conductance, susceptance and phase angle at different probe frequencies and resonant frequency. The RA group had a mild sensouneural hearing loss [SNHL] in the high frequencies with an average of 26.52 dBHL at 4kHz and 34.55dBHL at 8kHz which suggests inner ear affection. However, there was no statistically significant difference between the two groups as regards the air conduction pure tone average. Our RA group showed a higher mean resonant frequency [1038Hz +/- 251.18] than the control group [927.78Hz +/- 126.14] and this difference was statistically significant [p<0.05]. This suggests increased middle ear stiffness in RA, through a chronic inflammation that may involve the incudo-malleolar and/or incudo-stapedial diarthroidal joints. There was a correlation between resonant frequency and different disease parameters: The positivity of the rheumatoid factor, mean grade of disease activity, drug therapy and the presence of extra-articular manifestations. There was a direct correlation between resonant frequency and Erythrocyte sedimentation rate, rheumatoid factor, articular index and morning stiffness; and there was an inverse correlation between resonant frequency and grip strength of the patients. However, there was no correlation between resonant frequency and age of the patient, age of onset nor duration of the disease. MFT is more sensitive than single-frequency tympanometry to detect small changes in the mechanics of the tympano-ossicular chain in RA patients which can be used for the staging of RA, in addition to the traditional rheumatological parameters