Pleural effusion: adenosine deaminase helped diagnose tuberculous effusions.

Clinical bottom line (level 2b)

  1. In patients with suspected TB and pleural effusion, a positive adenosine deaminase test made tuberculous effusions more likely (LR+4.6) , and a negative one made them slightly less likely (LR-0.27) .
Maartens and Bateman: Thorax 1991; 46: 96-99
Expires November 2003

The study

Setting: teaching hospital, South Africa

111 patients (aged range 14 to 83 years; mean 38, ?% male) undergoing diagnostic pleural aspiration and biopsy (n=94); malignant disease and new pleural effusion (n=17)

Excluded if
  • <12 years old



    • Independent blinded reference standard, applied in some patients from a consecutive ?appropriate spectrum.
    Reference standard:
    • histology and/ or culture (for up to 8 weeks)
    Diagnostic test: adenosine deaminase (positive if >45 U/l)
    • The study was carried out in a community where tuberculosis notifications were 300-400/ 100, 000 population.

    The evidence

    pre-test probability of tuberculosis: 57%, (95% CI: 48% to 66%)

    diagnostic test tuberculosis no tuberculosis LR+
    (95% CI)    		 post-test probability LR-
    (95% CI)    		 post-test probability
    adenosine deaminase 48 8 4.6
    (2.4 to 8.7)     		86% 0.27
    (0.17 to 0.44)     		26%
    total 62 47

    Citation

    1. Maartens G, and Bateman ED: Tuberculous pleural effusions: increased culture yield with bedside inoculation of pleural fluid and poor diagnostic value of adenosine deaminase. Thorax 1991; 46: 96-99
    Contributor: Clare Wotton and Bob Phillips, November 2000
    Reviewer:

    Clinical Question.
    Patient suspected pleural effusion
    Intervention or Exposure adenosine deaminase
    Outcome tuberculous effusions