Gut Microbiome in Extremely Low-Birth-Weight Infants Influences Lung Damage Development

Recent research published in the journal Microbiome reveals a significant link between the gut fungi microbiome, known as the mycobiome, in very-low-birth-weight (VLBW) preterm infants and the development of oxygen-induced lung injury, particularly bronchopulmonary dysplasia (BPD). Extremely preterm infants, especially those weighing less than 3.3 pounds, often require high oxygen levels and mechanical ventilation, which can damage immature lungs and lead to BPD, a leading cause of mortality among these vulnerable infants.

In a comprehensive study conducted by researchers from the University of Alabama at Birmingham and the University of Tennessee Health Science Center, the gut fungi present in the second week of life, before clinical symptoms of BPD appear, were analyzed. The study examined stool samples collected from infants within the first two weeks after birth. Findings indicated that the diversity and composition of the infants' gut mycobiome differed markedly between those who later developed BPD and those who did not. Notably, bacterial differences were not significant in early stool samples.

To explore causality, researchers transferred stool samples—either associated with BPD prediction or not—into female mice to observe the effects. Mice receiving stool associated with BPD exhibited more severe lung injury, echoing the human condition. Furthermore, when antifungal treatments were administered to the dams of these pups, the severity of lung damage was reduced, suggesting that fungi play a causal role in lung injury. Conversely, increasing fungal colonization with a Candida species intensified lung injury in the mouse model.

Dr. Kent Willis, one of the lead researchers, commented that initial fungal colonization patterns in the gut might influence the development of BPD in preterm infants. The research highlights the potential for targeting the gut mycobiome as a therapeutic strategy to prevent or mitigate lung damage in these infants. The study underscores that a balanced and uniform fungal community may confer resistance to BPD, while discordant mycobiomes could predispose infants to disease.

This investigation adds a new dimension to understanding neonatal lung disease, emphasizing the importance of the gut microbiota, particularly fungi, in early development and long-term health outcomes in preterm infants.