Clinical trial NCT06594133: Longitudinal and Cross-sectional Analysis of Pulmonary Microbiota in Lung Transplant Recipients Infected With Nocardia
Official title: Longitudinal and Cross-sectional Analysis of Pulmonary Microbiota in Lung Transplant Recipients Infected With Nocardia: A Single-center Retrospective Study
Study type: OBSERVATIONAL
Overall status: COMPLETED
Conditions: Nocardia Infections
Lung Transplantation
Keywords: Nocardia;
Pulmonary Microbiota;
Retrospective Study;
Immunosuppression
Lead sponsor: Guangzhou Institute of Respiratory Disease
Sponsor class: OTHER
First posted: 2024-09-19
Enrollment: 68
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: no
Observational model: CASE_CONTROL
Time perspective: RETROSPECTIVE
Sampling method: NON_PROBABILITY_SAMPLE
Study population: This study includes lung transplant recipients treated at Guangzhou Medical University First Affiliated Hospital from January 2023 to August 2024, including patients diagnosed with Nocardia pneumonia and matched non-infected controls.

Brief summary: 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.

Detailed 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.

Eligibility criteria: 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

Primary outcomes:
measure: Pulmonary Microbiota Diversity in Nocardia-infected Lung Transplant Recipients
timeFrame: January 2023 to August 2024
Secondary outcomes:
measure: Correlation Between Pulmonary Microbiota and Clinical Outcomes
timeFrame: January 2023 to August 2024
Other outcomes:
Locations:
city: Guangzhou
country: China
facility: Guangzhou Institute of Respiratory Diseases, the First Affiliated Hospital of Guangzhou Medical University
state: Guangdong
Study officials:
References:
citation: Hemmersbach-Miller M, Catania J, Saullo JL. Updates on Nocardia Skin and Soft Tissue Infections in Solid Organ Transplantation. Curr Infect Dis Rep. 2019 Jun 21;21(8):27. doi: 10.1007/s11908-019-0684-7.
citation: Fatahi-Bafghi M. Nocardiosis from 1888 to 2017. Microb Pathog. 2018 Jan;114:369-384. doi: 10.1016/j.micpath.2017.11.012. Epub 2017 Nov 13.
citation: Restrepo A, Clark NM; Infectious Diseases Community of Practice of the American Society of Transplantation. Nocardia infections in solid organ transplantation: Guidelines from the Infectious Diseases Community of Practice of the American Society of Transplantation. Clin Transplant. 2019 Sep;33(9):e13509. doi: 10.1111/ctr.13509. Epub 2019 Mar 19.
citation: Lebeaux D, Morelon E, Suarez F, Lanternier F, Scemla A, Frange P, Mainardi JL, Lecuit M, Lortholary O. Nocardiosis in transplant recipients. Eur J Clin Microbiol Infect Dis. 2014 May;33(5):689-702. doi: 10.1007/s10096-013-2015-5. Epub 2013 Nov 23.
citation: Peleg AY, Husain S, Qureshi ZA, Silveira FP, Sarumi M, Shutt KA, Kwak EJ, Paterson DL. Risk factors, clinical characteristics, and outcome of Nocardia infection in organ transplant recipients: a matched case-control study. Clin Infect Dis. 2007 May 15;44(10):1307-14. doi: 10.1086/514340. Epub 2007 Apr 3.