Can We Prevent Cochlear Implant Recipients from Developing Pneumococcal Meningitis?

Abstract

The restoration of hearing to persons with severely or profoundly impaired hearing by means of a cochlear implant is one of the great achievements of bionics applied to medicine. However, pneumococcal meningitis in implant recipients has received high profile public attention as a result of the US Food and Drug Administration's public health notification and recent media attention. Worldwide, 118 of the 60,000 people who received cochlear implants over the past 20 years have acquired meningitis, causing deep concern in the international medical community. This review provides answers to pediatricians, internists, and infectious diseases doctors who have patients with cochlear implants and who have questions about the safety of the cochlear implant from both the clinical and scientific research perspectives. Both clinical and laboratory research support the notion that pneumococcal meningitis is more likely in patients who receive cochlear implantation, and that the surgical insertion technique and the cochlear implant design should be nontraumatic, and that all cochlear implant recipients should be offered vaccination against Streptococcus pneumoniae.

Cochlear Implants in Children: Surgical Site Infections and Prevention and Treatment of Acute Otitis Media and Meningitis

“…In the absence of a surgical procedure to reduce such risks, these children remain at increased risk of meningitis after cochlear implantation. In addition, as postulated by Arnold et al 21 and studied experimentally by Wei et al, 25 cases of bacterial meningitis in implant recipients may originate via pneumococcal bacteremia with hematogenous seeding of the cochlea, such as at a site of tissue necrosis related to the electrode or positioner (locus minoris resistentiae) with contiguous spread to the CSF and meninges.…”

Pneumococcal meningitis post cochlear implantation: Development of an animal model in the guinea pig

“…Even today meningitis following CI is a concern. Despite the efforts of health organizations and manufacturers to prevent post-operative infections, new cases of meningitis occur each year (Cohen et al, 2010;Lalwani et al, 2012;Wei et al, 2008). The question whether a CI represents a predisposing factor for meningitis irrespective of other risk factors remains unanswered and the possible underlying mechanisms need to be elucidated.…”

Recurrent bacterial meningitis after cochlear implantation in a patient with a newly described labyrinthine malformation

“…The first comprehensive study was published in 2002 [1] after reports about a few cases of death caused by postimplantation purulent meningitis were published. The summary of papers published since 2002 about this phenomenon [2][3][4][5] is that although CI does indeed increase the incidence of otogenic meningitis, this higher risk will, nevertheless, not contraindicate the procedure in light of the existing modern vaccines against meningitis and the advantages of CI--at least not in cases with normal inner ear anatomy.…”

“…Torkos et al phatic and CSF spaces are isolated from the middle ear until they are opened by the preparation of a cochleostomy during CI. It is also known that CI performed in ears with normal anatomy increase the risk of bacterial meningitis--this, however, does not contraindicate CI in light of the benefits of implantation, the existence of modern antibiotics and vaccines against meningogenic bacteria [1][2][3][4][5].…”