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A 65-year-old man from Chernobyl comes to the clinic with complaints of fever, productive cough, and weight loss for the last six months. He has no past medical history and is on no medications. His chest x-ray shows a right pleural effusion extending about halfway up the chest. Thoracentesis reveals: glucose 50 mg/dL, LDH 200 U/L, protein 4.5 g/dL, amylase 1.6 U/L. Cell count reveals 1,000 red cells/mL, with 6,000 white cells. The differential on the white cells is: neutrophils 10%, lymphocytes 80%, and monocytes 10%. The sputum stain is negative for acid-fast bacilli on three examinations. The sputum cytological evaluation does not reveal malignant cells. The V/Q scan is indeterminate on the right side because of the large pleural effusion, but there are no ventilation-perfusion mismatches elsewhere. What is the most accurate diagnostic test?
(A) Pleural-fluid culture for mycobacteria
(B) Pleural-fluid analysis for mycobacteria by polymerase chain reaction (PCR)
© PPD
(D) Biopsy of pleura
(E) Adenosine deaminase level
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hmmmm...tricky one
its an exudate sugested by LDH and protein level
now its either tubercular or malignant effusion
normally with malignancy LDH is very high...about 1000 and glucose is between 30-50
its more in favour of TB....
lymphocytosis of more than 85% is suggestive of TB...60-70% would be malignancy
everything goes in favour of TB
TB pleurisy is a hypersensitivity reaction...pleural fluid is diagnostic in only 10%
Adenosine deaminase more than 43 is a good indicator of TB but not very sensitive
biopsy with culture is diagnostic in 90%
so ...i will go for ddddddddddd as well
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The initial step in the evaluation of pleural effusion is to determine whether it is an exudate or a transudate. Exudates are generally caused by infections or cancer. Transudates are usually caused by problems with hydrostatic forces, such as congestive failure, cirrhosis, or nephrotic syndrome. This patient's effusion is an exudate based on the high LDH and protein levels in the fluid. When the pleural-fluid glucose level is less then 60 mg/dL, empyema or malignancy should be considered, although rheumatoid arthritis is also associated with a profoundly low pleural-fluid glucose level. Patients with an elevated amylase in the pleural fluid may have pancreatitis or an esophageal rupture. If the diagnosis is not apparent after these studies, an occult pulmonary embolism should be considered, especially if the fluid is bloody.
When a patient has a marked lymphocytic pleocytosis in the pleural fluid, you should suspect tuberculosis even if there are negative sputum stains for acid-fast bacilli (AFB). The most accurate test of those listed in this question for pulmonary tuberculosis is pleural biopsy. This is particularly true when there is a pleural effusion when repeated biopsies reach a sensitivity of >90%. Tissue examination is far more sensitive than pleural-fluid culture. A PPD would be completely nonspecific in a man from Russia who would almost certainly have a positive test anyway. Adenosine deaminase is elevated in third-space fluid collections from tuberculosis, such as the pleural, peritoneum, and pericardium. It is not as sensitive or specific as the pleural biopsy.
