Even though the density of lung microbiota is not significantly altered in children with pulmonary arterial hypertension (PAH) and congenital left-to-right shunts, the relative microbiome abundance of these patients is different from that of healthy controls and patients with congenital left-to-right shunts without pathologic features of PAH.
Moreover, the metabolome is also altered in patients with PAH and congenital left-to-right shunts. These are the findings of a new study published in Frontiers in Medicine.
The authors of the study concluded that pulmonary microbes and metabolites could potentially be effective biomarkers and “provide valuable perspectives on clinical diagnosis, treatment, and prognosis of pediatric PAH” and left-to-right shunts.
PAH associated with a congenital left-to-right shunt is a severe pediatric disease. The impact of lung microbiome changes on PAH patients with congenital left-to-right shunts is not well understood.
Read more about PAH
Here, a team of researchers led by Min Liu from the Department of Cardiovascular Surgery, Fuwai Yunnan Cardiovascular Hospital in Kunming, China, hypothesized that the lung microbiota and metabolites may be disturbed in children with PAH and congenital left-to-right shunts. This, they thought, might contribute to the progression and outcomes of the disease.
To test their hypothesis, the team enrolled 68 children, including pediatric patients with PAH and congenital left-to-right shunts, those with congenital left-to-right shunts but no associated PAH, and healthy controls. The researchers then conducted multiomics analysis, which included 16S ribosomal RNA sequencing and metabolomic profiling on bronchoalveolar lavage fluid samples from these children.
They found that the density of the microbial community in the lungs of children with PAH and congenital left-to-right shunts was not significantly different from that of the other 2 groups. However, in the lungs of these patients, species from the Bacteroidetes phylum were less abundant.
Moreover, Lactobacillus, Alicycliphilus, and Parapusillimonas species were significantly altered. The researchers suggested that this could contribute to PAH in these children. The metabolites involved in purine, pyrimidine, glycerophospholipid, and galactose metabolism were also significantly disturbed in the lungs of these patients.
When they conducted correlation analyses, the researchers found that changes in the microbial composition of the lungs of children with PAH and congenital left-to-right shunts could disturb certain metabolites and contribute to the pathology of the disease.
Ma R, Cheng L, Song Y, et al. Altered lung microbiome and metabolome profile in children with pulmonary arterial hypertension associated with congenital heart disease. Front Med (Lausanne). 2022;28;9:940784. doi:10.3389/fmed.2022.940784