Correspondence
Case 25-1996: Tuberculous Pleuritis
N Engl J Med 1997; 336:297-298January 23, 1997
- Article
To the Editor:
In his discussion of Case 25-1996 (Aug. 15 issue),1 Dr. Drapkin seems to doubt that measurement of the levels of adenosine deaminase in pleural fluid is useful for the diagnosis of pleural tuberculosis. It is true that other conditions can elevate the levels of adenosine deaminase in pleural effusions, especially empyema, rheumatoid arthritis, and some malignant conditions, but these entities can generally be ruled out easily on the basis of clinical findings and routine biochemical and cytologic determinations in pleural fluid. Moreover, it is possible that this problem may soon be resolved, because the results of polyacrylamide-gel electrophoresis, if confirmed, seem to indicate that there are two molecular forms of adenosine deaminase with a specific pattern for tuberculosis.2
Pleural biopsy is the diagnostic method of choice for pleural tuberculosis. The performance of three separate closed pleural biopsies, with microbiologic studies, has a diagnostic yield of about 90 percent.3 Levels of pleural-fluid adenosine deaminase above 47 to 70 U per liter (the cutoff value may vary between centers) have a sensitivity of 100 percent and specificity of 95 percent,3-5 for a diagnostic yield similar to that of pleural biopsies,3,5 at least in areas with a high prevalence of tuberculosis. This approach must be used with caution in Asians or immunocompromised patients because they appear to have lower levels of adenosine deaminase.3
We think that measurement of pleural-fluid adenosine deaminase is very useful for the diagnosis of pleural tuberculosis because its diagnostic yield is similar to that of pleural biopsy, but it has no complications and lower costs.
5 ReferencesEduardo Montero, M.D., Ph.D.
Ana Benito, M.D.
Joaquín López-Alvarez, M.D., Ph.D.
Hospital Universitario Príncipe de Asturias, 28805 Madrid, Spain1
Case Records of the Massachusetts General Hospital (Case 25-1996)
Full Text | Web of Science | Medline2
Ungerer JP ,Grobler SM . Molecular forms of adenosine deaminase in pleural effusions. Enzyme 1988;40:7-13
Medline3
Light RW. Tuberculous pleural effusions. In: Light RW, ed. Pleural diseases. 3rd ed. Baltimore: Williams & Wilkins, 1995:154-66.
4
Valdes L ,San Jose E ,Alvarez D , et al. Diagnosis of tuberculous pleurisy using the biologic parameters adenosine deaminase, lysozyme, and interferon gamma. Chest 1993;103:458-465
CrossRef | Web of Science | Medline5
Valdes L ,Alvarez D ,San Jose E , et al. Value of adenosine deaminase in the diagnosis of tuberculous pleural effusions in young patients in a region of high prevalence of tuberculosis. Thorax 1995;50:600-603
CrossRef | Web of Science | Medline
To the Editor:
The 38-year-old man with tuberculous pleuritis had classic hematologic manifestations of tuberculosis: monocytosis (17 percent) and a normochromic, presumably normocytic (mean corpuscular volume, 87 μm3), anemia with a hematocrit of 36.6 percent. The low serum albumin concentration of 2.8 g per deciliter is also classic. These measurements offer a low-cost, low-technology means of leading a good clinician to a rapid diagnosis of tuberculosis when a history of night sweats and weight loss is present. I am surprised that the discussants did not emphasize these findings. Perhaps the focus on rapid, high-technology procedures has obscured the diagnostic value of findings of hematologic and blood chemical abnormalities in tuberculosis.
Ann O'Neill Shigeoka, M.D.
University of Utah School of Medicine, Salt Lake City, UT 84132Author/Editor Response
Dr. Drapkin replies:
To the Editor: Montero and colleagues emphasize the usefulness of the measurement of pleural-fluid adenosine deaminase levels in distinguishing between tuberculous and nontuberculous pleuritis. The data are not clear-cut. Although the sources they cite uphold the validity of the test, there are other reports of sensitivities of 0.91,1 0.90,2 0.91,3 0.82,4 and 0.805 in various patient populations, with corresponding specificities of 0.81, 0.85, 0.98, 0.89, and 0.90. The test is a good one, as I mentioned in my discussion, but I believe not good enough to supplant biopsy, especially in a low-incidence population such as is encountered in a hospital in the United States.
Shigeoka properly emphasizes the results of routine hematologic and blood chemical analyses in suggesting the diagnosis of tuberculosis. However, when one is faced with a patient in whom the main diagnostic choice is between tuberculosis and lymphoma, as in the case under discussion, the specificity of these analyses will not permit a definitive diagnosis.
5 ReferencesMark S. Drapkin, M.D.
Newton–Wellesley Hospital, Newton, MA 021621
Burgess LJ ,Maritz FJ ,Le Roux I ,Taljaard JJ . Combined use of pleural adenosine deaminase with lymphocyte/neutrophil ratio: increased specificity for the diagnosis of tuberculous pleuritis. Chest 1996;109:414-419
CrossRef | Web of Science | Medline2
Villena V ,Navarro-Gonzalvez JA ,Garcia-Benayas C , et al. Rapid automated determination of adenosine deaminase and lysozyme for differentiating tuberculous and nontuberculous pleural effusions. Clin Chem 1996;42:218-221
Web of Science | Medline3
De Oliveira HG ,Rossatto ER ,Prolla JC . Pleural fluid adenosine deaminase and lymphocyte proportion: clinical usefulness in the diagnosis of tuberculosis. Cytopathology 1994;5:27-32
CrossRef | Web of Science | Medline4
Aoki Y ,Katoh O ,Nakanishi Y ,Kuroki S ,Yamada H . A comparison study of IFN-gamma, ADA, and CA125 as the diagnostic parameters in tuberculous pleuritis. Respir Med 1994;88:139-143
CrossRef | Web of Science | Medline5
Hsu WH ,Chiang CD ,Huang PL . Diagnostic value of pleural adenosine deaminase in tuberculous effusions of immunocompromised hosts. J Formos Med Assoc 1993;92:668-670
Medline
