Is it an exudate or not?
• Nicola Cooper, SpR medicine / elderly The Leeds Teaching Hospitals NHS Trust All the respondents seem sure this effusion is an exudate on the basis of protein level alone (see previous rapid response). This is the first question to answer. Competing interests: None declared Submit rapid responsePublished 30 March 2004 New diagnosis to be considered • José M Porcel, Internist Arnau de Vilanova University Hospital, 25198 Lleida, Spain Initially, I considered constrictive pericarditis as a probable diagnosis. I think it cannot be excluded, since echocardiography may be normal and cardiac catheterization may be neccesary to establish the diagnosis. However, other diseases need to be considered at this point. First, malignancy remains the most common etiology of undiagnosed exudative pleural effusions. The sensitivity of pleural cytology is only 60% on average. Thus, a negative result as in the present case does not rule out a malignant effusion. Except for breast cancer, which rarely pre
