Approach to classification of cavitary effusion and comparison between manual and automatic methods for total nucleated cell count

ABSTRACT

Background: Two classifications are used to categorize cavitary effusions using total nucleated cell count (TNCC) protein concentration and pathophysiology of its formation. The aims of the present study were to evaluate the correlation between the TNCC values of cavitary effusions obtained in the automatic and the manual method, and also evaluating the classification methodology.Materials, Methods & Results: Cavitary effusions were analyzed for physical, chemical and cytological aspects, as well as manual and automatic cell counts for the correlation between the traditional methods and those suggested by Stockham & Scott. Bland-Altman regression and Spearman correlation analysis were performed. Of the total, 44 were abdominal effusions (73.3%), 15 thoracic (25%) and 1 pericardial (1.7%). According to the traditional classification, most of the effusions were classified as modified transudates (40%) and according to the classification of Stockham and Scott, as transudates poor in protein (31.7%). The correlation between cell counting techniques between pure, modified and exudate transudates was 0.94, 0.97 and 0.94, respectively, indicating an excellent correlation between the parameters (P = 0.95%).Discussion: Considering the concentration of proteins and CCNT, the effusions classified as modified transudate were mainly caused by neoplastic processes (carcinomas/adenocarcinomas), since there are several mechanisms of their formation, such as large variation of protein concentration. According to the Stockham & Scott classification a unique classification is considered for exfoliative neoplastic effusions, the variation of the protein concentration of the effusion does not alter its classification. In neoplastic effusions, classified as exudates, lymphomas were the most prevalent, and hypercellularity (approximately 150,000 cells / μL) allowed this classification.[...]