Lab Test

Pleural Fluid Chemical Analysis

NOTE:

  • Dearborn performs Albumin, Amylase, Bilirubin, Cholesterol, Creatinine, Glucose, Lactate Dehydrogenase, pH, Protein, and Triglycerides.
  • Farmington Hills performs Albumin, Amylase, Glucose, Lactate Dehydrogenase, pH and Protein.
  • Grosse Pointe performs Albumin, Amylase, Glucose, Lactate Dehydrogenase, pH, Protein and Triglycerides.
  • Taylor performs pH.
  • Trenton performs pH.
  • Troy performs Albumin, Amylase, Bilirubin, Cholesterol, Glucose, Lactate Dehydrogenase, pH, Protein and Triglycerides.
  • Royal Oak performs Albumin, Amylase, Bilirubin, CA 19-9, Cholesterol, Glucose, Lactate Dehydrogenase, pH, Protein and Triglycerides. 
  • Wayne performs pH. 

Test Codes

Fluid Pleural, Thoracentesis, Albumin, Pleural Fluid, Left: EPIC: LAB6947, ALBP2, Albumin, Pleural Fluid, Right: EPIC: LAB6946, ALBPL, Amylase, Pleural Fluid, Left: EPIC: LAB6945, AMYP2, Amylase, Pleural Fluid, Right: EPIC: LAB6944,  AMYPL, Bilirubin, Pleural Fluid, Left: EPIC: LAB6953, BILP2, Bilirubin, Pleural Fluid, Right: EPIC: LAB6952, BILPL, Cholesterol, Pleural Fluid, Left: EPIC: LAB6949, CHPL2, Cholesterol, Pleural Fluid, Right: EPIC: LAB6948,  CHPLR, Glucose, Pleural Fluid, Left: EPIC: LAB6943, GLPLL, Glucose, Pleural Fluid, Right: EPIC: LAB6942, GLPLR, Lactate Dehydrogenase (LD), Pleural Fluid, Left: EPIC: LAB6941, LDPL2, Lactate Dehydrogenase (LD), Pleural Fluid, Right: EPIC: LAB6940, LDPLR, pH, Fluid: EPIC: LAB5259, PHFLD, Protein, Pleural Fluid, Left: EPIC: LAB6939, PRPL2, Protein, Pleural Fluid, Right: EPIC: LAB6938,  PRPLR, Triglycerides, Pleural Fluid, Left: EPIC: LAB6937, TRPL2, Triglycerides, Pleural Fluid, Right: EPIC: LAB6936, TRPLR, Carbohydrate Antigen 19-9, Pleural Fluid Left: EPIC: LAB7041, LC19P, Carbohydrate Antigen 19-9, Pleural Fluid Right: EPIC: LAB7042, RC19P

Department

Chemistry

Instructions

  • Pleural Fluid Chemical testing is available for the following analytes: Albumin, Amylase, Bilirubin, Cholesterol, Glucose, Lactate Dehydrogenase (LD), pH, Protein, and Triglycerides. This testing is not a panel and analytes are ordered individually. Please refer to the Lab Test Directory for testing of other analytes and fluid types.
  • Testing of fluid analytes or sources not listed in the Lab Test Directory must be approved by a Medical / Technical Director or Designee. Please contact the Laboratory for more information. 
  • Fluid pH specimens should ONLY be collected at the Dearborn, Farmington Hills, Grosse Pointe, Royal Oak, Taylor, Trenton, Troy, or Wayne Hospital campuses. Specimens should NOT be collected at any other Beaumont Laboratory drawsite, nursing home, or Outreach office.

Specimen Collection Criteria

Collect:

  • pH, Pleural FluidSpecimen MUST be collected in a heparinized blood gas syringe and transport immediately, on wet ice, to the Stat Laboratory (Royal Oak) or Chemistry Laboratory (Dearborn, Farmington Hills, Grosse Pointe, Taylor, Trenton, Troy, and Wayne).

NOTE: Any pH pleural fluid specimen collected in alternate containers (sterile container or red top plain tube) will be rejected.

  • All Other Specimens: Body fluid in a sterile collection container or Vacutainer® tube without additive. (Minimum: 1.0 mL)

          Send specimen for processing immediately after collection.

Physician Office/Draw Specimen Preparation

Maintain specimen refrigerated (2-8°C or 36-46°F) prior to transport. Room temperature (20-26°C or 68-78.8°F) is acceptable for a maximum of two hours.

Preparation for Courier Transport

Transport: Body fluid in a sterile collection container or Vacutainer® tube, refrigerated (2-8°C or 36-46°F). (Minimum: 1.0 mL)

Rejection Criteria

  • Specimens grossly contaminated with blood.
  • Specimens collected in a container or tube with an additive. 
  • pH, Fluid:  Any specimen collected in alternate containers (sterile container or red top plain tube) will be rejected.

In-Lab Processing

Before chemistry testing, centrifuge to remove cellular material.

Storage

Specimen Stability for Testing:

pH, Fluid: Blood Gas Syringe
Room Temperature (20-26°C or 68-78.8°F): Unacceptable
Refrigerated (2-8°C or 36-46°F): 1 hour
Frozen (-20°C/-4°F or below): Unacceptable

All Other Specimens
Room Temperature (20-26°C or 68-78.8°F): 2 hours
Refrigerated (2-8°C or 36-46°F): 7 days
Frozen (-20°C/-4°F or below): Undetermined

Specimen Storage in Department Prior to Disposal:

pH, Fluid: Blood Gas Syringe
Specimens are discarded within 8 hours of testing.

All Other Specimens
Refrigerated (2-8°C or 36-46°F): 30 days

Laboratory

Dearborn Chemistry Laboratory
Farmington Hills Chemistry Laboratory
Grosse Pointe Chemistry Laboratory
Royal Oak Automated Chemistry Laboratory
STAT Laboratory Royal Oak
Taylor Chemistry Laboratory
Trenton Chemistry Laboratory
Troy Chemistry Laboratory
Wayne Laboratory

Performed

Sunday – Saturday, 24 hours a day.
Results available within 4 hours of hours of receipt in the Laboratory.

Reference Range

See Interpretation below.

Test Methodology

  • Enzymatic, Spectrophotometry: Cholesterol, Triglycerides.
  • Potentiometry: pH.
  • Spectrophotometry: Albumin, Amylase, Bilirubin, Glucose, LD, Total Protein. 

Interpretation

  • Albumin: Serum albumin/pleural fluid albumin gradient of less than or equal to 1.2 g/dL is consistent with exudate.
  • Amylase: Pleural fluid amylase greater than the upper limit of normal (ULN) for serum amylase or pleural fluid amylase/serum amylase ratio greater than or equal to 1.5-2.0 is abnormal. Abnormal pleural fluid amylase is seen in pancreatitis, esophageal rupture, gastroduodenal perforation or malignant effusions.
  • Bilirubin: Pleural fluid bilirubin/serum bilirubin ratio of greater than 0.60 is consistent with exudate.
  • Cholesterol: Fluid cholesterol/serum cholesterol ratio greater than or equal to 0.3 or fluid cholesterol greater than 45 mg/dL is consistent with exudate.
  • Glucose: Pleural fluid glucose of less than 60 mg/dL or pleural fluid glucose/serum glucose ratio of less than 0.5 is abnormal. Abnormal pleural fluid glucose is seen in rheumatoid pleuritis and parapneumonic exudates. It can also be seen in malignancy, tuberculosis, SLE, and esophageal rupture.
  • Lactate Dehydrogenase (LD): Pleural fluid LD/serum LD ratio of greater than 0.60 or pleural fluid LD greater than 2/3rds the upper limit of normal serum LD is consistent with exudate. Pleural fluid LD/serum LD ratio of less than or equal to 0.60 or pleural fluid LD less than or equal to 2/3rds the upper limit of normal serum LD is consistent with transudate.
  • pH: An abnormally low pleural fluid pH helps to identify patients with effusions due to pneumonia or lung abscesses. Exudates with a pH lower than 7.3 can indicate the need for chest tube drainage in addition to antibiotics. A pH value as low as 6.0 may indicate esophageal rupture.
  • Total Protein: Pleural fluid TP/serum TP ratio of greater than 0.5 or pleural fluid total protein level greater than 3.0 g/dL is consistent with exudate. Pleural fluid TP/serum TP ratio of less than or equal to 0.5 or pleural fluid total protein level less than or equal to 3.0 g/dL is consistent with transudate. Using total protein alone misclassifies exudates and transudates in about 30% of cases. Sensitivity and specificity increases to 98% and 80%, respectively, when using both total protein and LD criteria.
  • Triglycerides: Pleural fluid triglyceride levels greater than or equal to 110 mg/dL is indicative of chylous effusion. Pleural fluid triglyceride level less than 50 mg/dL is indicative of non-chylous effusion. Levels between 50-109 mg/dL are equivocal.
  • Carbohydrate Antigen 19-9 (CA 19-9): Elevated pleural fluid CA 19-9 is suspicious, but not diagnostic, of a malignant source of the effusion. CA 19-9 concentrations may be significantly higher in effusions caused by CA 19-9-secreting malignancies, including cholangiocarcinoma, colorectal, stomach, bile duct, lung, ovarian, and pancreatic cancers. However, non-CA 19-9-secreting malignancies may cause effusions. Therefore, negative results should be interpreted with caution, especially in patients who have or are suspected of having a non-CA 19-9-secreting malignancy. Tumor marker results should be correlated with cytology and imaging. 

Clinical Utility

Useful initially, in the classification of an effusion as an exudate or a transudate.

Reference

  1. Henry's Clinical Diagnosis and Management by Laboratory Method's, 22nd Ed. 2011.

CPT Codes

82042 (Albumin), 82150 (Amylase), 82247 (Bilirubin, Total), 82465 (Cholesterol), 82945 (Glucose), 83615 (LD), 83986 (pH), 84157 (Protein, Total), 84478 (Triglycerides).

LOINC: Cholesterol 12183-0, Glucose 2344-0, Lactate Dehydrogenase 14803-1, Lactate Dehydrogenase LT & RT 14803-1, Triglycerides 9619-8, Triglycerides Pleural LT & RT 9619-8, Albumin Pleural Fluid LT & RT 1748-3, Amylase Pleural LT & RT 1795-4, Bilirubin Pleural LT & RT 1974-5, Carbohydrate Pleural LT & RT 24108-3, Cholesterol Pleural LT & RT 12183-0, Glucose Pleural LT & RT 2344-0.

Contacts

Last Updated

6/27/2024

Microtainer® and Vacutainer® are registered trademarks of Becton, Dickinson and Company.
UroVysion® is a registered trademark of Abbott Laboratories. ThinPrep® is a registered trademark of Hologic, Incorporated.