Related Experiment Video
Updated: Aug 29, 2025
Bronchoalveolar Lavage BAL for Research; Obtaining Adequate Sample Yield
Published on: March 24, 2014
External quality assessment of flow cytometric bronchoalveolar lavage cellular analysis: 20 years' experience in The
A H Leontine Mulder1, Harrie H M Eidhof2, Jan W Gratama3
1Medlon B.V., Department of Clinical Chemistry and Laboratory Medicine, Enschede and Clinical Chemistry, Ziekenhuis Groep Twente, Almelo, The Netherlands.
Insights
A dedicated external quality assessment (EQA) for bronchoalveolar lavage (BAL) fluid analysis was developed. This EQA ensures reliable cellular analysis for interstitial lung disease diagnosis, achieving adequate quality control.
Area of Science:
- Immunology
- Pulmonary Medicine
- Clinical Chemistry
Background:
- Bronchoalveolar lavage (BAL) cellular analysis aids interstitial lung disease diagnosis.
- Conventional flow cytometry of BAL cells is challenging due to cell properties.
- Existing external quality schemes (EQA) for blood are not representative for BAL fluid analysis.
Purpose of the Study:
- To establish and evaluate a dedicated EQA for BAL fluid cellular analysis.
- To assess the quality of flow cytometric analysis of BAL cells over 20 years.
- To determine the representativeness of BAL fluid analysis compared to peripheral blood.
Main Methods:
- A specialized EQA procedure for stabilized BAL cells was implemented.
- Flow cytometric parameters (lymphocyte subsets, eosinophils, neutrophils) were recorded from 2000-2020.
- Data analysis included calculating means, standard deviations, and comparing results over time and by disease.
Main Results:
- Median standard deviation was below 10% for most parameters, except TLY and CD103+CD3+ lymphocytes.
- No significant time-based improvement was observed for most cell populations, except CD3+CD4+ lymphocytes.
- Interpretation consensus varied by disease, with highest agreement for sarcoidosis and lowest for nonspecific interstitial lung disease.
Conclusions:
- A dedicated EQA for BAL fluid cellular analysis is justified due to its unique characteristics.
- Adequate analytical and post-analytical quality control can be achieved with this specialized EQA.
- This EQA improves the reliability of BAL fluid analysis for interstitial lung disease diagnosis.
Background:
Bronchoalveolar (BAL) cellular analysis can be supportive in the diagnosis of interstitial lung disease. The flow cytometric analysis of BAL fluid cells is complicated by cell fragility and adherence and autofluorescence of macrophages, making conventional analysis of BAL fluid cells as done in external quality schemes (EQA) for blood lymphocyte subsets, not representative. Following a procedure for stabilized BAL cells, a separate EQA was set up. The results of 20 years' experience are presented.
Methods:
From each round between 2000 and 2020 the following flow cytometric parameters were recorded from each participant: total lymphocyte population (TLY), CD3+ lymphocytes, CD3+ CD4+ lymphocytes, CD3+ CD8+ lymphocytes, CD3- CD16+/56+ lymphocytes, CD19+ lymphocytes and CD103 + CD3+ lymphocytes. In addition, the eosinophils and neutrophils were recorded. The mean and standard deviation of each parameter per round were calculated. The 40 rounds were divided in four respective groups of 10 in order to compare the results as function of time. In addition the interpretation of the results of participants was scored.
Results:
The median SD in the four groups was below 10% for all parameters except for TLY and the CD103+ CD3+ lymphocytes. No improvement in time was observed for any (sub)population except for the CD3+ CD4+ subset. Interpretation of the results varied based on disease, with greatest consensus for sarcoidosis cases and lowest for nonspecific interstitial lung disease cases.
Conclusions:
A dedicated EQA for BAL fluid cellular analysis appears to be justified as the test material is substantially different from that of peripheral blood. We show that adequate analytical and post-analytical quality control can be achieved.
