Bacterial meningitis among children with cochlear implants beyond 24 months after implantation.

BACKGROUND: More than 11000 children in the United States with severe-to-profound hearing loss have cochlear implants. A 2002 investigation involving pediatric cochlear implant recipients identified meningitis episodes from January 1, 1997, through September 15, 2002. The incidence of pneumococcal meningitis in the cohort was 138.2 cases per 100000 person-years, >30 times higher than that for children in the general US population. Children with implants with positioners were at higher risk than children with other implant models. This higher risk of bacterial meningitis continued for up to 24 months after implantation. OBJECTIVE: To evaluate additional reported cases to determine whether the increased rate of bacterial meningitis among children with cochlear implants extended beyond 24 months after implantation. METHODS: Our study population consisted of the cohort of children identified through the 2002 investigation; it included 4265 children who received cochlear implants in the United States between January 1, 1997, and August 6, 2002, and who were <6 years of age at the time of implantation. We calculated updated incidence rates and incidence according to time since implantation. RESULTS: We identified 12 new episodes of meningitis for 12 children. Eleven of the children had implants with positioners; 2 children died. Six episodes occurred >24 months after implantation. When cases identified in the 2002 and 2004 investigations were combined, the incidence rate of > or =24-months postimplantation bacterial meningitis among children with positioners was 450 cases per 100000 person-years, compared with no cases among children without positioners. CONCLUSIONS: Our updated findings support continued monitoring and prompt treatment of bacterial infections by health care providers and parents of children with cochlear implants. This vigilance remains important beyond 2 years after implantation, particularly among children with positioners. The vaccination recommendations for all children with implants, with and without positioners, and all potential recipients of implants continue to apply.

Risk of bacterial meningitis in children with cochlear implants.

BACKGROUND: In June 2002, the Food and Drug Administration received reports of bacterial meningitis in patients with cochlear implants for treatment of hearing loss. Implants that included a positioner (a wedge inserted next to the implanted electrode to facilitate transmission of the electrical signal by pushing the electrode against the medial wall of the cochlea) were voluntarily recalled in the United States in July 2002. METHODS: We identified patients with meningitis and conducted a cohort study and a nested case-control investigation involving 4264 children who had received cochlear implants in the United States between January 1, 1997, and August 6, 2002, and who were less than six years of age when they received the implants. We calculated the incidence of meningitis in the cohort and assessed risk factors for meningitis among patients and among 199 controls, using data from interviews with parents and abstracted from medical records. RESULTS: We identified 26 children with bacterial meningitis. The incidence of meningitis caused by Streptococcus pneumoniae was 138.2 cases per 100,000 person-years--more than 30 times the incidence in a cohort of the same age in the general U.S. population. Postimplantation bacterial meningitis was strongly associated with the use of an implant with a positioner (odds ratio, 4.5 [95 percent confidence interval, 1.3 to 17.9], with adjustment for medical, surgical, and environmental factors) and with the joint presence of radiographic evidence of a malformation of the inner ear and a cerebrospinal fluid leak (adjusted odds ratio, 9.3 [95 percent confidence interval, 1.2 to 94.5]). The incidence of meningitis among patients who had received an implant with a positioner remained higher than the incidence among those whose implants did not have a positioner for the duration of follow-up (24 months from the time of implantation). CONCLUSIONS: Parents and health care providers should ensure that all children who receive cochlear implants are appropriately vaccinated and are then monitored and treated promptly for any bacterial infections after receiving the implant.