When children die from a severe form of malaria, swelling of the brain is often what kills them, a new study finds.
This insight will not change medical practice immediately, but it may lead to improved treatments, researchers said.
The disease, caused by a parasite spread by mosquitoes, is a major killer in the tropics. Worldwide, there were 198 million cases in 2013. About 500,000 people died, mostly children in Africa. There is no vaccine. Drugs can prevent the infection and treat it, but malaria can still be rapidly fatal even with treatment, especially in young children.
Cerebral malaria, which involves the brain, is an extremely dangerous form of the disease and can lead to coma and death. Fifteen percent to 25 percent of African children who contract this type of malaria die. Survivors can be left deaf, blind or with learning disabilities.
Doctors suspected that brain swelling had a role in fatal cases, but the evidence was not clear.
Hoping to resolve the issue, researchers in Malawi performed M.R.I. scans on 168 children whose illness met a strict definition of cerebral malaria. The results were published on Wednesday in The New England Journal of Medicine.
Twenty-five children died, 21 of whom — 84 percent — had severe brain swelling. Among the survivors, only 27 percent had severe swelling.
“What’s killing these kids is that they stop breathing, because the respiratory center in the brain stem is compressed by the swelling,” said Dr. Terrie E. Taylor, the senior author of the study and a professor at the Michigan State University College of Osteopathic Medicine. She spends about half the year working in Malawi.
Ventilators might save some children, Dr. Taylor said, by maintaining their breathing through the worst of the brain swelling, which usually lasts for only a few days. Ventilators are not widely available in Africa, but providing them “is not beyond the pale,” she said.
Certain drugs, including steroids and mannitol, may also help with brain swelling, but studies are needed to find out, she said.
Correction: March 21, 2015
An article on Thursday about brain swelling in children who suffer from cerebral malaria omitted part of the name of the institution where Dr. Terrie E. Taylor, the lead author of a new study, works. She is at Michigan State University College of Osteopathic Medicine, not at Michigan State College of Osteopathic Medicine.