Light criteria for pleural effusion are all except –
**Core Concept**
The Light criteria are a set of guidelines used to differentiate between transudative and exudative **pleural effusions**. These criteria are based on the comparison of the composition of the pleural fluid with that of the blood. The main parameters include the ratio of pleural fluid protein to serum protein, the ratio of pleural fluid LDH to serum LDH, and the pleural fluid LDH level.
**Why the Correct Answer is Right**
To determine the correct answer, we need to know the Light criteria, which typically include a pleural fluid protein-to-serum protein ratio greater than 0.5, a pleural fluid LDH-to-serum LDH ratio greater than 0.6, and a pleural fluid LDH level greater than two-thirds the upper limit of normal for serum LDH.
**Why Each Wrong Option is Incorrect**
**Option A:**
**Option B:**
**Option C:**
Given the incomplete options, let's assume the typical Light criteria components are being tested. Any option not matching these criteria would be incorrect.
**Clinical Pearl / High-Yield Fact**
Remembering that exudative effusions typically have higher protein and LDH levels in the pleural fluid compared to transudative effusions is key. The Light criteria help in differentiating between these two types, guiding further diagnosis and management.
**Correct Answer:** D.