كاربرد آلكالين فسفاتاز به عنوان معيار افتراق پلورال افيوژن اگزوداتيو از ترانسوداتيو

ALKALINE PHOSPHATASE ASSESSING IN DIFFERENTIATION OF EXUDATIVE FROM TRANSUDATIVE PLEURAL EFFUSION

BACKGROUND AND OBJECTIVE: Light criteria (protein and LDH) and cholesterol is commonly used to differentiate exudative from transudative pleural effusion. Application of both parameters is time consuming and relatively expensive. This study was done to determine the role of alkaline phosphatase (ALP) assessment in differentiation of exudative from transudative pleural effusion and the comparison with light criteria and cholesterol. METHODS: This study was performed on all patients with pleural effusion referred to Shahid Beheshti hospital (Babol, Iran) during 1998-2001. Biological (protein, LDH, cholesterol and alkaline phosphatase), cytologic and bacteriologic tests were performed on all pleural fluid and blood samples of patients. Sixty four patients were followed up till final diagnosis. The results of light criteria and cholesterol were compared to alkaline phosphatase activity according to accuracy and sensitivity of separation of pleural effusion. FINDINGS: In 43 patients (67%), pleural effusions were exudates and in 21 patients (33%) were transudates. The parameter of alkaline phosphatase in dissociation of exudative from transudative pleural effusion had a sensitivity, specificity and accuracy of 88%, 100% and 90%, respectively while light criteria was with sensitivity of 96% and specificity of 77%. CONCLUSION: ALP revealed a similar accuracy to light criteria in exudative pleural effusion diagnosis. Because of higher specificity for ALP than light criteria, it will be more accurate in differentiation of transudative from exudative pleural effusion.