Predictive models for diagnosis of pleural effusions secondary to tuberculosis or cancer.
OBJECTIVE
Tuberculosis (TB) and cancer are two of the main causes of pleural effusions which frequently share similar clinical features and pleural fluid profiles. This study aimed to identify diagnostic models based on clinical and laboratory variables to differentiate tuberculous from malignant pleural effusions.


METHODS
A retrospective study of 403 patients (200 with TB; 203 with cancer) was undertaken. Univariate analysis was used to select the clinical variables relevant to the models composition. Variables beta coefficients were used to define a numerical score which presented a practical use. The performances of the most efficient models were tested in a sample of pleural exudates (64 new cases).


RESULTS
Two models are proposed for the diagnosis of effusions associated with each disease. For TB: (i) adenosine deaminase (ADA), globulins and the absence of malignant cells in the pleural fluid; and (ii) ADA, globulins and fluid appearance. For cancer: (i) patient age, fluid appearance, macrophage percentage and presence of atypical cells in the pleural fluid; and (ii) as for (i) excluding atypical cells. Application of the models to the 64 pleural effusions showed accuracy higher than 85% for all models.


CONCLUSIONS
The proposed models were effective in suggesting pleural tuberculosis or cancer.
Sales
Roberta K B
RK
Pulmonary and Clinical Laboratory (ICHC) Divisions, Heart Institute (InCor), University of São Paulo Medical School, São Paulo, Brazil. roberta.sales@uol.com.br
Vargas
Francisco S
FS
Capelozzi
Vera Luiza
VL
Seiscento
Márcia
M
Genofre
Eduardo H
EH
Teixeira
Lisete R
LR
Antonangelo
Leila
L
D000243:Adenosine Deaminase / Q000378:metabolism; D000328:Adult; D000368:Aged; D001706:Biopsy; D001943:Breast Neoplasms / Q000150:complications; D003661:Decision Support Techniques; D003937:Diagnosis, Differential; D005260:Female; D005833:Genital Neoplasms, Female / Q000150:complications; D006801:Humans; D008175:Lung Neoplasms / Q000150:complications; D008264:Macrophages / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000150:complications*; D035422:Pleural Cavity / Q000201:enzymology / Q000473:pathology; D010996:Pleural Effusion / Q000175:diagnosis* / Q000209:etiology* / Q000473:pathology; D016066:Pleural Effusion, Malignant / Q000175:diagnosis* / Q000209:etiology* / Q000473:pathology; D011471:Prostatic Neoplasms / Q000150:complications; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014376:Tuberculosis / Q000150:complications*
D000243:Adenosine Deaminase