Hearing loss in individuals at risk for neurosyphilis

Otosyphilis is a serious complication of syphilis.329 participants enrolled in a study of cerebrospinal fluid (CSF) abnormalities in syphilis underwent portable audiometry (250 Hz to 8000 Hz at 5-75 dB); it was repeated in 33 after otosyphilis treatment. Treponema pallidum spp pallidum (T. pallidum) DNA in blood was quantitated by polymerase chain reaction. Odds ratios (ORs) or hazard ratios (HRs) with 95% confidence intervals (CIs) were determined by logistic, ordinal or Cox regression.166 (50.5%) had normal hearing; 15 (4.6%) had low frequency (LF) loss alone, 93 (28.3%) had high frequency (HF) loss alone, and 55 (16.7%) had both. Adjusted odds of any hearing loss were higher with detectable blood T. pallidum DNA (3.00 [1.58-5.69], p = 0.001), CSF pleocytosis (2.02 [1.12-3.66], p = 0.02), and older age (2.22 per 10-year increase, [1.70-2.91], p < 0.001). HRs of normalization of LF and HF loss were lower for older individuals (0.20 [0.07-0.63, p = 0.005] and 0.22 [0.05-0.94, p = 0.04]), and HRs for normalization of HF loss were lower for those with more severe loss (0.09 [0.02-0.43], p = 0.002), and in those with CSF pleocytosis (0.32 [0.11-0.96], p = 0.04).Older age and CSF pleocytosis increase the likelihood of otosyphilis and impair hearing recovery after otosyphilis treatment.