Nearly half of children who survive an episode of bacterial meningitis experience persistent behavioral, intellectual, or other complications, reports a study in the January issue of the Pediatric Infectious Disease Journal.
"While neurologic deficits may resolve over time, subtle behavioral deficits may not be appreciated initially and may continue to affect survivors for many years," according to the new study, led by Dr. Aruna Chandran of Johns Hopkins University, Baltimore.
Through a comprehensive review of published studies, the researchers identified 1,433 patients who were survivors of childhood bacterial meningitis. The analysis focused on the rates and types of long-term complications—the children in the studies were followed up for at least five years, and in some cases more than 20 years.
Overall, 49.2 percent of the children have at least one type of long-term complication. Nearly 80 percent of the complications were classified as behavioral and/or intellectual deficits—most commonly low IQ or "cognitive impairment." Other problems in this category included behavioral problems and attention deficit hyperactivity disorder.
Most of the remaining 20 percent of complications were major neurological abnormalities and hearing impairments. There were some differences in types of long-term complications among children with different bacterial causes of meningitis. However, the specific causative bacteria were confirmed in just over one-fourth of the children studied.
Bacterial meningitis is a potentially fatal infection of the tissues lining the brain and spinal cord. In recent years, vaccines protecting against bacteria that commonly cause meningitis have led to significant reductions in the rates of childhood meningitis, although with a shift to different types of causative bacteria.
Previous studies have reported on various types of complications in survivors of childhood meningitis. However, most have included relatively short follow-up periods or focused on one specific type of complication.
The new results provide a more complete picture of the rates and types of long-term complications in childhood survivors of bacterial meningitis. Approximately 50 percent of these children have some type of complication, most commonly related to academic performance or behavioral problems.
Previous studies have found that at least some of the obvious neurological abnormalities seen after childhood meningitis will resolve within a few years. "In contrast" Chandran and co-authors write, "subtle neurologic deficits, such as impaired school performance, behavioral problems, and attention deficit disorder, may not be appreciated initially and may continue to affect survivors for many years."
Further research will be needed to provide a more complete picture of the types and rates of long-term complications among children who survive meningitis. Meanwhile, Chandran and co-authors believe that the full impact of these long-term complications should be an important consideration in making recommendations for the use of vaccines against common bacterial causes of meningitis.