Diagnostic Value of Lactate Dehydrogenase in Pericardial Effusions in Patients Undergoing Pericardiocentesis

Kim, Sung Eun; Park, Dae Gyun

Abstract

BACKGROUND/AIMS
Unlike pleural effusions or ascites, few studies have examined the role of chemical and cell-count parameters in the etiologic diagnosis of pericardial effusion. We determined the cut-off points of chemical parameters that can differentiate the causes of pericardial effusion.
METHODS
This study included 45 patients who underwent pericardiocentesis from 2003 to 2010. We examined the cell count and chemistry of blood and pericardial fluid, and divided the patients into a systemic group (the pericardium and myocardium were not invaded directly, such as in uremia and hypothyroidism) and a local inflammation group (the pericardium or myocardium was involved directly, such as in malignancy, tuberculosis, infection, and connective tissue disease).
RESULTS
Common causes of pericardial effusion requiring pericardiocentesis were malignancy (42.8%), iatrogenic (11.9%), and tuberculosis (9.5%). The pericardial lactate dehydrogenase (LDH) level and pericardial/serum (P/S) LDH ratio were higher in the local inflammation group than the systemic group (288.33 +/- 143.9 vs. 2,372.07 +/- 3,916.00 IU/L, p = 0.002, and 5.7 vs. 0.6, p = 0.007, respectively). The discrimination accuracy of the P/S LDH ratio (1.12) and pericardial fluid LDH level (435 IU/L) for predicting local inflammation was significant, as evidenced by the respective areas under the receiver operating characteristic curves of 0.84 (sensitivity 81.4%, specificity 81.5%) and 0.88 (sensitivity 83.3%, specificity 81.5%).
CONCLUSIONS
The LDH level (435 IU/L) of pericardial fluid and P/S LDH ratio (1.12) in patients with a pericardial effusion can help to differentiate between systemic causes and other diseases directly involving the pericardium.