Fig. 2.

Variation of hearing thresholds across ages and frequencies in patients with Muckle-Wells syndrome (MWS). a Comparison of hearing threshold within a family with MWS. Audiogram of a 5 year-old child with MWS (a-1): Standard hearing assessment in the 4PTA range including 0.5, 1, 2, and 4 kHz was normal (light gray area). In contrast the proposed HF-PTA captured a dramatic early high frequency hearing loss with increased hearing thresholds at 6 and 8 kHz (dark grey area). The child’s 37-year old father reported hearing impairment. The corresponding audiogram (a-11) revealed abnormally increased hearing thresholds across all frequencies (light and dark grey areas). In the father advanced MWS associated hearing loss is captured not only by HF-PTA but also by standard 4PTA. b Comparison of hearing thresholds of standard 4 pure-tone-average (4PTA) and proposed high frequency pure-tone-average (HF-PTA) in children and adults with MWS and age-matched healthy controls across the age spectrum. Normal hearing thresholds captured in 4PTA and HF-PTA increase with age (4PTA grey line, HF-PTA black line). MWS patients of all ages have significantly higher 4PTAs (black circles) and HF-PTAs (grey triangles) even after adjusting for age-specific normal hearing thresholds