Adenosine Deaminase Diagnostic Testing in Pericardial Fluid

A 65-year-old Vietnamese man with hypertension, type 2 diabetes mellitus, and chronic hepatitis B with cirrhosis presented with a 2-week history of shortness of breath at rest, orthopnea, and lower extremity edema. He reported a 4-month history of nonproductive cough, 5-kg weight loss, and fatigue. He immigrated to the United States as an adult more than 20 years before presentation. His temperature was 37°C, heart rate was 78/min, respiratory rate was 17/min, and blood pressure was 158/95 mm Hg. A chest radiographic image suggested cardiomegaly and a computed tomographic scan demonstrated a moderate to large pericardial effusion. A pericardial drain was placed and pericardial fluid was sent to the laboratory for evaluation. Initial pericardial fluid study results are presented in the Table. Empirical treatment for tuberculosis was initiated. Three days later, an adenosine deaminase (ADA) level of 118.1 U/L (normal range, 0.0-11.3 U/L) from pericardial fluid was reported from the laboratory.