Longitudinal and Cross-sectional Analysis of Pulmonary Microbiota in Lung Transplant Recipients Infected With Nocardia (NocardiaLM)

Zhibin Xu

Status: Completed

Conditions: Nocardia Infections; Lung Transplantation

Treatments: Drug: Antibiotic Treatment

Study type: Observational

Funder types: Other

Identifiers

NCT06594133

ES-2024-K144

Details and patient eligibility

About

This retrospective observational study aims to explore the impact of Nocardia infection on the pulmonary microbiota of lung transplant recipients (LTRs). The study will analyze both cross-sectional and longitudinal data from patients diagnosed with Nocardia pneumonia, comparing microbial composition and diversity between infected and non-infected groups. This research seeks to provide insights into the relationship between pulmonary microbiota alterations and clinical outcomes in LTRs.

Full description

This study is a single-center, retrospective, observational study designed to investigate the impact of Nocardia infection on the pulmonary microbiota of lung transplant recipients (LTRs). The study will include both cross-sectional and longitudinal analyses. In the cross-sectional study, 17 LTRs diagnosed with Nocardia pneumonia (Nocardia pneumonia group, NPG) will be compared with 51 non-infected LTRs (non-Nocardia infection group, NNIG) matched for age, sex, and underlying conditions.

The longitudinal study will follow LTRs over a 4-month period, collecting samples before, during, and after treatment. Patients in this group will be categorized into the Recovered group (RG) or Not Recovered group (NRG) based on treatment outcomes. The study will also include a subgroup analysis of patients with disseminated Nocardia infection, comparing pulmonary and systemic microbiota changes.

Microbial diversity and composition will be assessed using high-throughput sequencing of bronchoalveolar lavage fluid (BALF) samples. Statistical analyses will include the Kolmogorov-Smirnov test, ANOVA, and Kruskal-Wallis test for group comparisons, with linear mixed-effects models used to analyze changes over time.

The goal of this study is to provide a deeper understanding of how Nocardia infection affects the pulmonary microbiota in LTRs and to identify key microbial species associated with clinical outcomes.

Enrollment: 68 patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Lung transplant recipients
• Diagnosed with Nocardia pneumonia (for the study group)
• Age ≥ 18 years

Exclusion criteria

• Patients with incomplete medical records
• Patients who survived ≤ 3 days after transplantation
• Patients lost to follow-up

Trial design

68 participants in 2 patient groups

Nocardia Pneumonia Group (NPG)

Description:

This group consists of lung transplant recipients diagnosed with Nocardia pneumonia. The patients in this group are studied to assess the impact of Nocardia infection on the pulmonary microbiota. Samples including bronchoalveolar lavage fluid (BALF) and blood are collected for microbial community analysis.

Treatment:

Drug: Antibiotic Treatment

Non-Nocardia Infection Group (NNIG)

Description:

This group consists of lung transplant recipients who are not infected with Nocardia. These patients serve as the control group and are matched with the Nocardia pneumonia group based on clinical characteristics such as age, sex, and underlying conditions.