UKMLA PLAB AMC USMLE Prometric MCQ

Correct Answer: D

Explanation:
A Pleural fluid LDH-to-serum LDH ratio. <0.6 is suggestive of a transudate.  1. Laboratory differentiation.   Specific gravity. Under 1.016 is suggestive of a transudate.  Protein. Less than 3 g/dl is suggestive of a transudate.  Pleural fluid protein-to-serum protein ratio. <0.5 is suggestive of a transudate.   Pleural fluid LDH-to-serum LDH ratio. <0.6 is suggestive of a transudate.   The pleural fluid level is not useful in the differential diagnosis of exudative pleural effusion. Nevertheless, it is recommended that a pleural fluid LDH level be measured every time a diagnostic thoracentesis is performed, since the level of LDH in the pleural fluid is a good indicator of the degree of inflammation in the pleural space. If the pleural fluid LDH level increases with serial thoracentesis, the degree of inflammation is worsening and one should be more aggressive in pursuing the diagnosis