By: Lucaiah Smith-Miodownik, News Writer
Content warning: mentions of fatal infection.
Neonatal sepsis (NS) is a deadly condition for newborn babies within the first 28 days of life. As the body cannot properly respond to infections caused by common bacteria like “E. coli, Listeria, and Group B streptococcus,” as well as “viruses, fungi, and parasites,” infants can develop NS. The condition leads to “an estimated 200,000 deaths worldwide each year, with the highest rates in lower- and middle-income countries.”
Early-onset sepsis, occurring in the baby’s first three to seven days of life, is generally caused by perinatal risk factors. Perinatal refers to the period of time a birth parent first becomes pregnant and “up to a year after giving birth.” Perinatal risk factors include “infection in the placenta and amniotic fluid,” a birthing parent’s water breaking early, or bacteria that have “colonized” in the internal reproductive system during pregnancy. Late-onset sepsis, found after three to seven days, is often caused by bacteria in a hospital setting, transmitted through “medical equipment such as catheters, IVs, and tubes.” However, signifiers of NS, such as irritability or feeding issues for the newborn, are “often non-specific” and “can also be associated with non-infectious causes,” making the condition difficult to diagnose.
Until recently, most studies regarding NS have focused on the infection after diagnosis. However, a new discovery from a group of UBC and SFU researchers, along with Medical Research Council Unit The Gambia, could change that. “Critically, our prospective study provided the unique opportunity to identify gene expression biomarkers that could predict, at birth, which healthy-appearing neonates will develop sepsis, and to follow these neonates during sepsis,” reported the team.
“Knowing that sepsis is impending would also allow physicians more time to determine the appropriate treatment to use.” — Dr. Bob Hancock, professor of microbiology and immunology at UBC
The team mapped “the expression of genes active at birth” in 720 apparently healthy newborns in the country of The Gambia. When they mapped them, they discovered “four genes that, when combined in a ‘signature,’ could accurately predict sepsis in newborns nine times out of 10,” as described by SFU assistant professor of molecular biology and biochemistry, as well as co-senior author of the study Dr. Amy Lee. This signature was identified through RNA sequencing (RNA-seq) on blood samples. RNA-seq is a technique used to help understand “gene expression levels,” which provide information on how cells function.
The ability to detect NS before diagnosis “is vital for infants’ survival,” Dr. Beate Kampmann, professor of pediatric infection and immunity at the London School of Hygiene and Tropical Medicine, told SFU. “Knowing that sepsis is impending would also allow physicians more time to determine the appropriate treatment to use,” UBC professor of microbiology and immunology Dr. Bob Hancock also told SFU. “Providing an early diagnosis to assist and guide physicians could save lives,” he said. Infants with NS are commonly treated with antibiotics, but “the uncertainty can delay urgent treatment.”
The next steps for the team include “a large prospective study” with other populations. The team hopes the signature can be integrated into hospitals and point-of-care testing. This refers to tests that can be run “at, or near, the site of a patient,” and don’t need to be sent off to a laboratory for results.
For more information, see the published study linked in the online article.
