Microflora of Retained Intracochlear Electrodes from Infected Cochlear Implants

Area of Science:

• Otolaryngology
• Infectious Diseases
• Microbiology

Background:

• Cochlear implant infections can necessitate device removal and reimplantation.
• Intracochlear electrode arrays are often retained during removal to prevent cochlear lumen obliteration.
• Retained electrodes may pose a contamination risk for reimplanted devices.

Purpose of the Study:

• To compare microorganisms on infected cochlear implants with those on retained intracochlear electrodes.
• To assess the microbial burden of retained intracochlear electrodes using culture and gene sequencing.
• To evaluate the risk of contamination associated with retaining intracochlear electrodes.

Main Methods:

• Prospective single-cohort study at a tertiary medical center.
• Six patients with refractory cochlear implant infections underwent receiver-stimulator and extracochlear electrode removal.
• Intracochlear electrodes were analyzed via microbial culture and 16S DNA gene sequencing post-removal.

Main Results:

• Staphylococcus aureus was the most frequently identified organism on infected implants.
• No intracochlear electrodes yielded microbes via culture.
• Gene sequencing detected bacterial species on 2 electrodes and fungal species on 1 electrode.
• No correlation was found between microbes on infected implants and retained electrodes.

Conclusions:

• Intracochlear electrodes from infected cochlear implants harbor a low microbial load.
• Retaining intracochlear electrodes during infected cochlear implant removal presents a minimal risk of contaminating reimplanted devices.