Researchers have found that infants develop a microbiome in their lungs before birth. The diversity of microbiota predicts risk for neonatal lung disease. The findings are in a paper just published in the journal Scientific Reports.
Lung problems are more common for premature extremely low birth-weight infants, or ELBWs. Bronchopulmonary dysplasia (BPD) is a chronic lung disease associated with premature births. Infants with BPD have an increased risk for serious health complications and mortality. The lungs in BPD infants don’t develop correctly and this can lead to problems later in life, including asthma and pulmonary hypertension.
Researchers from the University of Alabama studied both premature low weight infants and full-term infants from neonatal care units. They found that the infants had already developed microbiota in their lungs prior to birth. Previously, it was believed that they gained beneficial bacteria in the birth canal during delivery but the results were the same for both vaginal and caesarean births.
ELBW infants who developed BPD were found to have a lower diversity of beneficial microbes in their airways. They also had fewer bacteria from the genus Lactobaccillus. Lactobaccillus bacteria are known to play a role in disease resistance. ELBW infants who didn’t go on to develop lung problems had healthy populations of these bacteria. A lack of Lactobaccillus bacteria was also associated with chorioamnionitis, an infection of the membranes and fluid surrounding the fetus.
The research team isn’t sure where the microbes originate. Since infants had developed lung microbiomes regardless of the type of birth, the authors speculate that the microbes are delivered transplacentally. Infants may acquire the bacteria through blood or amniotic fluid.
The researchers hope their findings will lead to better treatments and preventatives for lung diseases such as BPD. By analyzing the beneficial bacteria in healthy infants’ airways, probiotics could be developed for ELBW infants.
Charitharth Vivek Lal et al. The Airway Microbiome at Birth. Scientific Reports (2016).