Cytomegalovirus Seropositivity as a Potential Risk Factor for Increased Noise Trauma Susceptibility

Area of Science:

• Otolaryngology
• Virology
• Immunology

Background:

• Cytomegalovirus (CMV) is the leading cause of congenital viral infections.
• While congenital CMV is primary, adult CMV infections can have clinical significance.
• The impact of CMV seropositivity from horizontal infection in immunocompetent adults on dysfunction is debated.

Purpose of the Study:

• To investigate if CMV seropositivity is an additional risk factor for sensorineural hearing loss (SNHL) induced by acoustic injury in adult guinea pigs.
• To assess the correlation between CMV seropositivity and noise-induced hearing loss (NIHL) in a guinea pig model.

Main Methods:

• Two groups of guinea pigs, CMV seropositive and seronegative, were exposed to broadband noise (115 dB SPL for 2 hours).
• Auditory brainstem response (ABR) was used to determine auditory threshold shifts.
• Outer hair cell loss was quantified 2 weeks post-noise exposure.

Main Results:

• CMV seropositive animals showed a slightly increased auditory threshold shift compared to seronegative controls after noise trauma.
• This difference was statistically significant, particularly at high frequencies.
• No correlation was found between threshold shift and outer hair cell loss between groups.

Conclusions:

• CMV seropositivity may contribute to additional pathologies in a guinea pig NIHL model.
• Latent or reactivated CMV infection should be considered when assessing risks for hearing loss.
• Future studies with larger sample sizes are needed to explore target structures and infection route significance.