Effusions: pleural, peritoneal, pericardial
PCR alone had a sensitivity of 74% and specificity of 87% (13% false positive).
Testing panels included at least 2 of the following:
(1) PCR
(2) adenosine deaminase activity (ADA, positive if >= 38 IU/L)
(3) absolute lymphocyte count (ALC, positive if >= 275 per µL)
If at least one of these tests is positive, then the sensitivity is 100%.
The specificity was highest (96%) for
(1) both PCR and ADA are positive (specificity 67% if only one positive)
(2) both PCR and absolute lymphocyte count are positive (specificity 75% if only one positive)
The specificity when only one of ADA or ALC was positive was 67%.
The performance of test combinations is affected by the prevalence of tuberculosis, especially when the prevalence is low.
