Detection of Pneumonia in Infants with Non-Human Immunodeficiency Virus Admitted to Pediatric Intensive Care Using Metagenomics Next-Generation Sequencing.

OBJECTIVE

This study aimed to investigate the characteristics of the non-human immunodeficiency virus (HIV) pneumocystis pneumonia (PCP) via the microbial composition of pneumonia in the lower respiratory tract in infants with severe pneumonia who were hospitalized in the study's pediatric intensive care unit (PICU).

METHODS

The clinical characteristics of 16 infants with non-HIV PCP (the PCP group) and 33 infants with severe pneumonia (the control group) who were hospitalized at the same time in the PICU were analyzed retrospectively. Using metagenomic next-generation sequencing (mNGS), the bronchoalveolar lavage fluid (BALF) of the two groups was analyzed, and the microbial results and clinical data were compared.

RESULTS

Compared with the control group, the infants in the PCP group had a lower incidence of cough (25% vs 78.8%; < 0.05), a greater history of surgery (50.0% vs 39.1%; < 0.05), and a more significant decrease in C3, C4, and CD4/CD8 ratios (all < 0.05). The pathogenic bacteria in the BALF included , respiratory syncytial virus, cytomegalovirus (CMV), and . The predominance of viral infection in the PCP group was significantly higher than in the control group ( < 0.05), especially CMV (43.5% vs 15.2%; < 0.05). The top five symbiotic microorganisms detected in the BALF of the 49 infants were , and . There was no significant difference in the relative abundance of common symbiotic microorganisms between the two groups (all > 0.05).

CONCLUSION

Non-HIV PCP has a higher incidence in PICU infants with severe pneumonia, especially those with underlying diseases or who are immunocompromised, which are clinically difficult to treat. A BALF analysis using mNGS is helpful for early and clear diagnoses. It also helps to clarify the distribution of pathogenic and lower respiratory tract colonizing bacteria in infants with severe pneumonia.