Laurits Frøssing1, Thomas Hartvig Lindkaer Jensen2, Jesper Østrup Nielsen3, Morten Hvidtfeldt1, Alexander Silberbrandt1, Deborah Parker4, Celeste Porsbjerg1, Vibeke Backer5. 1. Respiratory Research Unit, Copenhagen University Hospital, Bispebjerg and Frederiksberg, Denmark. 2. Department of Pathology, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark. 3. Department of Clinical Biochemistry, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark. 4. Leicester Respiratory Biomedical Research Unit, University of Leicester, Leicester, United Kingdom. 5. Center for Physical Activity Research, Copenhagen University Hospital Rigshospitalet, Copenhagen, Denmark.
Abstract
INTRODUCTION: Cell differential count (CDC) of induced sputum is considered the gold standard for inflammatory phenotyping of asthma but is not implemented in routine care due to its heavy time- and staff demands. Digital Cell Morphology is a technique where digital images of cells are captured and presented preclassified as white blood cells (neutrophils, eosinophils, lymphocytes, macrophages, and unidentified) and nonwhite blood cells for review. With this study, we wanted to assess the accuracy of an automated CDC in identifying the key inflammatory cells in induced sputum. METHODS: Sputum from 50 patients with asthma was collected and processed using the standard processing protocol with one drop 20% albumin added to hinder cell smudging. Each slide was counted automatically using the CellaVision DM96 and manually by an experienced lab technician. Sputum was classified as eosinophilic or neutrophilic using 3% and 61% cutoffs, respectively. RESULTS: We found a good agreement using intraclass correlation for all target cells, despite significant differences in the cell count rate. The automated CDC had a sensitivity of 65%, a specificity of 93%, and a kappa-coefficient of 0.61 for identification of sputum eosinophilia. In contrast, the automated CDC had a sensitivity of 29%, a specificity of 100%, and a kappa-coefficient of 0.23 for identification of sputum neutrophilia. CONCLUSION: Automated- and manual cell counts of sputum agree with regards to the key inflammatory cells. The automated cell count had a modest sensitivity but a high specificity for the identification of both neutrophil and eosinophil asthma.
INTRODUCTION: Cell differential count (CDC) of induced sputum is considered the gold standard for inflammatory phenotyping of asthma but is not implemented in routine care due to its heavy time- and staff demands. Digital Cell Morphology is a technique where digital images of cells are captured and presented preclassified as white blood cells (neutrophils, eosinophils, lymphocytes, macrophages, and unidentified) and nonwhite blood cells for review. With this study, we wanted to assess the accuracy of an automated CDC in identifying the key inflammatory cells in induced sputum. METHODS: Sputum from 50 patients with asthma was collected and processed using the standard processing protocol with one drop 20% albumin added to hinder cell smudging. Each slide was counted automatically using the CellaVision DM96 and manually by an experienced lab technician. Sputum was classified as eosinophilic or neutrophilic using 3% and 61% cutoffs, respectively. RESULTS: We found a good agreement using intraclass correlation for all target cells, despite significant differences in the cell count rate. The automated CDC had a sensitivity of 65%, a specificity of 93%, and a kappa-coefficient of 0.61 for identification of sputum eosinophilia. In contrast, the automated CDC had a sensitivity of 29%, a specificity of 100%, and a kappa-coefficient of 0.23 for identification of sputum neutrophilia. CONCLUSION: Automated- and manual cell counts of sputum agree with regards to the key inflammatory cells. The automated cell count had a modest sensitivity but a high specificity for the identification of both neutrophil and eosinophil asthma.
Authors: Vivek Kumar Singh; Md Mostafa Kamal Sarker; Yasmine Makhlouf; Stephanie G Craig; Matthew P Humphries; Maurice B Loughrey; Jacqueline A James; Manuel Salto-Tellez; Paul O'Reilly; Perry Maxwell Journal: Cancers (Basel) Date: 2022-08-13 Impact factor: 6.575