Table 3. Descriptive analysis of the parameters determined in the pleural fluid.
| Parameter | n (%) | Median | Range | Comments |
|---|---|---|---|---|
| Nucleated cells (cells/mm3) | 22 (25.0) | 651 | 50–47,500 | 5/22 (22.7%) >2,000 cells/mm3 (29,47,61,68,70). Positive culture in the PF with 47,500 cells/mm3 (61) |
| Differential count (%) | ||||
| Lymphocyte cells | 9 (10.2) | 16 | 4–95 | 4/9 (44.4%) >50% (27,30,59,65) |
| Polymorphonuclear cells | 13 (14.7) | 47 | 2–100 | 5/13 (38.5%) >50% (21,39,47,61,70) |
| PF proteins (g/dL) | 44 (50.0) | 0.92 | 0.1–7 | 7/44 (15.9%) >3 g/dL (14,15,27,47,49,50,59) |
| PF/S proteins ratio | 20 (22.7) | 0.14 | 0.029–0.65 | 4/20 (20%) >0.5 (50,59,63,66) |
| PF LDH (IU/L) | 27 (30.7) | 210 | 25–3,475 | 14/27 (51.9%) >200 IU/L (15,30,31,39,57-59,61,68,71-73,78) |
| PF/S LDH ratio | 20 (22.7) | 0.7 | 0.039–17.6 | 11/20 (55%) >0.6 (15,49,57,59,61,63,66,68,73,78) |
| PF glucose (mg/dL) | 28 (31.8) | 110 | 0–188 | 6/28 (21.4%) ≤60 mg/dL (15,39,61,68,70,71) |
| PF/S glucose ratio | 5 (5.7) | 0.74 | 0–1 | Only one case <0.5 (PF glucose, 0 mg/dL) (15) |
| pH | 26 (29.5) | 7.24 | 6.80–8.40 | 16/26 (61.5%) ≤7.30; 6/26 (23.1%) ≥7.50 |
| PF CEA (ng/mL) | 3 (3.4) | – | 0.09–41 | Inconclusive data (only 3 patients). Very high values in one case (39) |
| PF/S creatinine ratio | 48 (54.5) | 2.9 | 0.95–16 | 97.9% with PF/S creatinine ratio >1 (47/48); in the case with ratio <1, PF was extracted 16 hours after the placement of the chest tube (63) |
PF, pleural fluid; PF/S ratio, pleural fluid/serum ratio; LDH, lactate dehydrogenase; CEA, carcinoembrionic antigen.