The repeatability of nonbronchoscopic bronchoalveolar lavage differential cell counts

Airway inflammation in children can be assessed by nonbronchoscopic bronchoalveolar lavage (BAL). Little is known about the repeatability of cell counts in the BAL obtained. Children (n=43) attending for elective surgery were studied. Cell counts were obtained following a nonbronchoscopic lavage. Two samples were obtained with either: 1) the catheter wedged in the same position (n=21) or 2) the catheter reinserted and wedged again (n=22). Slides (n=30) from nonbronchoscopic lavage samples were selected at random and two independent observers counted 500 cells on each slide on two occasions. The repeatability of the lavage sampling and cell counting was assessed for different cell types. The inter- and intra-observer repeatability for the differential cell counting demonstrated that there was good repeatability for all cell types except lymphocytes (interobserver: Lin's concordance coefficient 0.42; repeatability coefficient 0.66). Quantification of eosinophil (%) was highly repeatable using either method (Lin's concordance coefficient 1) 0.99, 2) 0.95; repeatability coefficient 1) 0.58, 2) 1.36). Nonbronchoscopic lavage is a repeatable technique for the quantification of eosinophils. Variation in the sampling method can be reduced by taking two separate samples and averaging the differential cell counts. Furthermore, increasing the number of cells counted should ensure accurate quantification of lymphocytes.

[1]  Pavord,et al.  Between‐observer repeatability of sputum differential cell counts. Influence of cell viability and squamous cell contamination , 1997, Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology.

[2]  D. Altman,et al.  Statistics notes: Measurement error , 1996 .

[3]  M. Silverman,et al.  Induced sputum in children: feasibility, repeatability, and relation of findings to asthma severity. , 2000, Thorax.

[4]  M. Hirvonen,et al.  Reproducibility of measurements of exhaled NO, and cell count and cytokine concentrations in induced sputum. , 2000, The European respiratory journal.

[5]  D. Altman,et al.  STATISTICAL METHODS FOR ASSESSING AGREEMENT BETWEEN TWO METHODS OF CLINICAL MEASUREMENT , 1986, The Lancet.

[6]  J. Bousquet,et al.  Comparison between bronchial and alveolar samples of bronchoalveolar lavage fluid in asthma. , 1992, Chest.

[7]  S. Rennard,et al.  Fractional processing of sequential bronchoalveolar lavage to separate bronchial and alveolar samples. , 1990, The American review of respiratory disease.

[8]  M. Ennis,et al.  Bronchoalveolar lavage findings suggest two different forms of childhood asthma , 1997, Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology.

[9]  D. B. Ettensohn,et al.  Bronchoalveolar lavage in the normal volunteer subject. 2. Safety and results of repeated BAL, and use in the assessment of intrasubject variability. , 1988, Chest.

[10]  M. Silverman,et al.  Fractional processing of sequential bronchoalveolar lavage fluid from intubated babies. , 1992, The European respiratory journal.

[11]  N. Cox,et al.  Concordance correlation coefficient , 1999 .

[12]  D. Altman,et al.  Measurement error. , 1996, BMJ.

[13]  J. Salvaggio,et al.  Reliability of cell counts and protein determinations in serial bronchoalveolar lavage procedures performed on healthy volunteers. , 1990, The American journal of the medical sciences.

[14]  L. Lin,et al.  A concordance correlation coefficient to evaluate reproducibility. , 1989, Biometrics.

[15]  W. M. Brutinel,et al.  Interlobar variation in the recovery of bronchoalveolar lavage fluid, cell populations, and angiotensin-converting enzyme in normal volunteers. , 1993, The Journal of laboratory and clinical medicine.

[16]  A. Clément,et al.  Bronchoalveolar lavage in children. ERS Task Force on bronchoalveolar lavage in children. European Respiratory Society. , 2000 .

[17]  M. Ennis,et al.  Investigating paediatric airways by non‐bronchoscopic lavage: normal cellular data , 1996, Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology.

[18]  P. Lalor,et al.  Bronchoalveolar lavage in the normal volunteer subject. I. Technical aspects and intersubject variability. , 1988, Chest.

[19]  A. Spanevello,et al.  Induced sputum to assess airway inflammation: a study of reproducibility , 1997, Clinical and experimental allergy : journal of the British Society for Allergy and Clinical Immunology.

[20]  F. Ratjen,et al.  Bronchoalveolar lavage in children , 2000 .

[21]  A. Clément,et al.  Bronchoalveolar lavage in children. ERS Task Force on bronchoalveolar lavage in children. European Respiratory Society. , 2000 .