Hearing thresholds at high frequency in patients with cystic fibrosis: a systematic review

Extended High-Frequency Audiometry for Ototoxicity Monitoring: A Longitudinal Evaluation of Drug-Resistant Tuberculosis Treatment

PURPOSE

The aim of this study was to describe extended high-frequency (EHF) pure-tone audiometry monitoring of ototoxicity in a longitudinal treatment program for drug-resistant tuberculosis (DRTB).

METHOD

This was a retrospective record review of longitudinal conventional (0.25-8 kHz) and EHF (9-16 kHz) audiometry for ototoxicity monitoring of DRTB patients undergoing treatment at community-based clinics between 2013 and 2017. Data from 69 patients with an average age of 37.9 years (SD = 11.2, range: 16.0-63.8 years) were included. Patients were assessed by primary health care audiologists (87%) or community health workers (13%) using portable audiological equipment. The average length of time between initial and exit assessments was 84.6 days (SD = 74.2, range: 2-335 days).

RESULTS

EHF ototoxicity of a mild or greater degree of hearing loss (> 25 dB HL in one or both ears across frequencies) was evident in 85.5% of patients' posttreatment, compared with 47.8% of patients across conventional frequencies. EHF audiometry demonstrated an ototoxic shift (American Speech-Language-Hearing Association criteria) in 56.5% of cases compared with 31.9% when only conventional audiometry was considered. Mean hearing deterioration for patients was significant across EHFs (9-16 kHz) bilaterally (p < .05). Absent EHF thresholds at the initial assessment, owing to maximum output limits, was a limitation that occurred most frequently at 16 kHz (17.4%, 24/138).

CONCLUSIONS

EHF audiometry is most sensitive for the early detection of ototoxicity and should be included in monitoring programs. Clinical ototoxicity monitoring protocols should consider shortened assessment approaches that target frequencies most sensitive to ototoxicity, including EHFs.

SUPPLEMENTAL MATERIAL

https://doi.org/10.23641/asha.21651242.

Hearing Impairment in the Extended High Frequencies in Children Despite Clinically Normal Hearing

OBJECTIVES

Pediatric hearing impairment, regardless of degree and type, has a detrimental effect on speech perception, cognition, oral language development, academic outcomes, and literacy. Hearing assessment in the clinic is limited to 8 kHz although humans can hear up to 20 kHz. Hearing impairment in the extended high frequencies (EHFs > 8 kHz) can occur despite clinically normal hearing. However, to date, the nature and effects of EHF hearing impairment in children remain unknown. The goals of the present study were to determine the effects of EHF hearing impairment on speech-in-noise recognition in children and to examine whether hearing impairment in the EHFs is associated with altered cochlear functioning in the standard frequencies.

DESIGN

A volunteer sample of 542 participants (4 to 19 years) with clinically normal audiograms were tested. Participants identified with EHF impairment were assigned as cases in a subsequent case-control study. EHF loss was defined as hearing thresholds greater than 20 dB in at least one EHFs (10, 12.5, or 16 kHz). Speech recognition thresholds in multi-talker babble were measured using the digit triplet test. Distortion product otoacoustic emissions ( f2 = 2, 3, 4, and 5 kHz) were measured to assess cochlear functioning.

RESULTS

Thresholds in the EHFs were as reliable as those in the standard frequency range. Thirty-eight children had EHF hearing impairment regardless of a clinically normal audiogram. A linear mixed-effects model revealed that children with EHF hearing impairment had higher (poorer) mean speech recognition threshold than children with normal EHF sensitivity ( estimate = 2.14 dB, 95% CI: 1.36 to 3.92; effect size = small). The overall magnitude of distortion product otoacoustic emissions was lower for children with EHF impairment ( estimate = -2.47 dB, 95% CI: -4.60 to -0.73; effect size = medium). In addition, the pure-tone average for standard audiometric frequencies was relatively higher for EHF-impaired children ( estimate = 3.68 dB, 95% CI: 2.56 to 4.80; effect size = small).

CONCLUSIONS

Hearing impairment in the EHFs is common in children despite clinically normal hearing and can occur without a history of otitis media. EHF impairment is associated with poorer speech-in-noise recognition and preclinical cochlear deficits in the lower frequencies where hearing thresholds are normal. This study highlights the clinical need to identify EHF impairments in children.

Ototoxicity in cystic fibrosis patients receiving intravenous tobramycin for acute pulmonary exacerbation: Ototoxicity following tobramycin treatment

Aminoglycosides are commonly used to treat infections in CF patients and are highly ototoxic. The incidence of tobramycin-induced hearing loss, tinnitus, vertigo or dizziness (ototoxicity) varies widely from 0 to 56% secondary to variation in patient enrollment, dosing, audiometry, and ototoxic criteria. The aim of this study is to determine the incidence of ototoxicity after one course of once-daily IV tobramycin in CF patients. Adult CF patients with acute pulmonary exacerbations were enrolled on IV tobramycin (10 mg/kg/d, ≥10 days). Pure-tone audiometry was performed for standard and extended high frequencies in the sensitive range for ototoxicity (SRO). American-Speech-Language-Hearing-Association cochleotoxicity criteria were applied. Distortion product otoacoustic emissions (DPOAE) and the words-in-noise-test (WINT) were assessed. Tinnitus Functional Index (TFI) and Vertigo Symptoms Scale (VSS) were used. Eighteen CF patients, mean age 31.1 (18-59), were enrolled. The incidence of cochleotoxic change from baseline at 2 and 4 weeks post-treatment was 89% and 93%. For DPOAE, a measure of outer hair-cell function, the incidence of ≥5 dB decrease was 82% and 80%. For WINT, a measure of word recognition, the incidence of ≥10% decrease was 17% and 40%. For TFI, the incidence of ≥10pt increase was 12% and 8%, and for VSS, the incidence of ≥6pt increase was 0% and 8%. One course of IV tobramycin was sufficient to cause hearing loss and other ototoxic symptoms four weeks after treatment ended. Audiometric measures were more sensitive to ototoxic change than TFI & VSS. Age and duration of tobramycin treatment were not obvious factors for predicting ototoxicity.