Lab Test

Peritoneal Fluid Chemical Tests


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

Test Codes

Fluid Peritoneal, Paracentesis, Albumin, Peritoneal Fluid: EPIC: LAB6933,  ABPYL, Amylase, Peritoneal Fluid: EPIC: LAB6931, AYPYL, Bilirubin, Peritoneal Fluid: EPIC: LAB6955, BILPN, CA 19-9, Peritoneal Fluid: EPIC: LAB6958,  C19PL, Cholesterol, Peritoneal Fluid: EPIC: LAB6950, CHPYL, Creatinine, Peritoneal Fluid: EPIC: LAB6956, CRPYL, Glucose, Peritoneal Fluid: EPIC: LAB6934, GLPYL, Lactate Dehydrogenase (LD), Peritoneal Fluid: EPIC: LAB6959,  LDPYL, pH, Fluid: EPIC: LAB5259, PHFLD, Protein, Peritoneal Fluid: EPIC: LAB6954, PRPYL, Triglycerides, Peritoneal Fluid: EPIC: LAB6951, TRPYL


  • Peritoneal Fluid Chemical testing is available for the following analytes: Albumin, Amylase, Bilirubin, CA 19-9, Cholesterol, Creatinine, Glucose, Lactate Dehydrogenase (LD), 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 Director. Please contact the Laboratory for more information.
  • Fluid pH specimens should ONLY be collected at the Grosse Pointe, Royal Oak, or Troy Hospital campuses. Specimens should NOT be collected at any other Beaumont Laboratory drawsite, nursing home, or Outreach office.

Specimen Collection Criteria


  • pH, Fluid: Collect in a blood gas syringe and transport immediately, on wet ice, to the Stat Laboratory (Royal Oak) or Chemistry Laboratory (Grosse Pointe and Troy).
  • 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. 

In-Lab Processing

Before chemistry testing, centrifuge to remove cellular material.


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


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


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

Reference Range

  • Albumin: Because of the wide range of albumin levels seen in serous body fluids, results are best evaluated by using the serum albumin ascites gradient. A gradient greater than 1.1 g/dL predicts portal hypertension with 97-98% accuracy and is seen in transudates. A gradient less than or equal to 1.1 g/dL is usually seen with exudates.
  • Amylase: Values greater than or equal to three times (3x) a simultaneously analyzed serum value, are considered abnormal in ascites of pancreatic origin. Other peritoneal and intestinal disorders may also cause elevation of amylase.
  • Bilirubin, Peritoneal Fluid: Ascitic fluid bilirubin levels have been examined in patients with various forms of ascites. Ascitic fluid bilirubin concentration greater than 6 mg/dL and an ascitic fluid to serum bilirubin ratio of greater than 1.0 appears to be consistent with bile peritonitis.
  • CA 19-9: Less than 35 U/mL. This test was performed using the Siemens Centaur, Chemiluminescent method. Values obtained with different assay methods or kits cannot be used interchangeably. This test should not be interpreted as absolute evidence for the presence or absence of malignant disease.
  • Cholesterol: Less than 48 mg/dL.
  • Creatinine: 0.5 – 2.0 mg/dL.
  • Glucose: Reference range approximates that found in serum.
  • LD (Lactate Dehydrogenase): Less than 63 U/L.
  • Protein, Total:
    • Transudates: Less than 3.0 g/dL.
    • Exudates: Greater than or equal to 3.0 g/dL.
  • Triglycerides: Less than 65 mg/dL.

Test Methodology

  • Chemiluminescence Immunoassay: CA 19-9.
  • Enzymatic, Spectrophotometry: Cholesterol, Triglycerides.
  • Spectrophotometry: Albumin, Amylase, Creatinine, Glucose, LD, Total Bilirubin, Total Protein.


  • Albumin: A serum ascites albumin gradient greater than or equal to 1.1 g/dL is consistent with portal hypertension from causes such as cirrhosis, congestive heart failure, or portal vein thrombosis. A low gradient (less than 1.1 g/dL) occurs in conditions such as peritoneal carcinomatosis, peritoneal tuberculosis, pancreatitis, serositis, and nephrotic syndrome. In the past a value of greater than or equal to 1.1 g/dL was interpreted as a transudate, and if less than 1.1 g/dL the fluid was interpreted as an exudate.
  • Amylase: Increased concentrations of amylase in peritoneal and pleural fluid may reflect acute inflammation of the pancreas, mumps, perforated peptic ulcers, and other medical conditions.
  • Bilirubin, Total: Elevated body fluid bilirubin is suggestive of an exudative fluid. This testing should be performed in conjunction with other testing including serum bilirubin analysis, body fluid/serum protein ration, body fluids/serum lactate dehydrogenase ratio, and serum lactate dehydrogenase. Determination of body fluid bilirubin concentration can aid in the distinction between a transudative and an exudative fluid. Bilirubin values tend to be higher in exudates than in transudates, although there is some overlap between groups. However, a ratio of body fluids to serum bilirubin has been reported to identify exudative body fluids with sensitivity, specifically, positive predictive accuracy, and absolute accuracy equivalent to that obtained using Light's criteria for an exudative pleural fluid (pleural/serum protein ratio greater than 0.5, pleural/serum lactate dehydrogenase ratio greater than 0.6, and serum lactate dehydrogenase greater than 200 U/L).
  • CA 19-9: Measuring CA 19-9 in peritoneal fluid can be used as an adjunct to cytology to differentiate between malignancy-related ascites and benign causes of ascites formation. Do not use peritoneal fluid carbohydrate antigen CA 19-9 (CA 19-9) levels as absolute evidence of the presence or absence of malignant disease. The evaluation and diagnosis of malignancy-related ascites is based on the patient clinical history, ascites fluid analysis and imaging tests.
  • Cholesterol: Peritoneal fluid cholesterol determination can distinguish cirrhotic versus malignant ascites.
  • Creatinine: Measurement of creatinine is useful to differentiate between peritoneal fluid and urine. Elevated peritoneal fluid creatinine, in association with normal serum creatinine, suggests urinary bladder leakage or rupture.
  • Glucose: Glucose measurement in body fluid may be useful with other laboratory tests to evaluate effusions. Decreased concentrations are associated with bacterial infections, inflammation such as rheumatoid arthritis, and occasionally malignancy.
  • LD: Measuring LD in fluid aspirated from a pleural effusion (or pericardial effusion) can help in the distinction between exudates (actively secreted fluid, e.g. due to inflammation) and transudates (passively secreted fluid, due to a high hydrostatic pressure or a low oncotic pressure). The most reliable method for differentiating between transudates and exudates is the simultaneous analysis of fluid and serum for lactic dehydrogenase (LD) and total protein level.
  • pH: Peritoneal fluid pH may be helpful in diagnosis of spontaneous bacterial peritonitis – in the presence of neutrophils, a pH of less than 7.32 or a blood-ascitic fluid pH difference of more than 0.1 has a sensitivity and specificity of about 90%. Low pH is also seen with tuberculous, malignant, and pancreatic ascites.
  • Protein, Total: See Clinical Utility below.
  • Triglycerides: Peritoneal fluid triglyceride determination can distinguish cirrhotic versus malignant ascites.

Clinical Utility

  • Useful initially, in the classification of an effusion as an exudate or a transudate.
  • Total Protein Interpretation: Measurement of total protein in body fluids other than blood, urine, or cerebrospinal fluid is usually done to differentiate an inflammatory fluid collection (exudate) from one that is non-inflammatory (transudate). In pericardial, peritoneal, pleural, and synovial fluids, 3 g/dL is usually taken as the cut-off value for differentiating transudates from exudates. Some authors use a lower cut-off of 2.5 g/dL. Some references suggest using a ratio of fluid to serum protein to differentiate transudate from exudate. Protein is just one of several markers that can be used for differentiating transudates from exudates. Low total protein is seen in patients with cirrhosis of the liver when ascites develops late in the disease. Patients with a low value, below 1.5 g/dL, are at greater risk of developing spontaneous bacterial peritonitis. Knowing that the concentration is low has some prognostic value, although it should not be a reason for beginning prophylactic antibiotic therapy.


  1. Kjeldsberg's Body Fluid Analysis. J.W. Hussong & C.R. Kjeldberg, eds. American Society for Clinical Pathology. 2015.
  2. D.S. Karcher & R.A. McPherson. Cerebrospinal Synovial, Serous Body Fluids and Alternative Specimens. Henry's Clinical Diagnosis and Management by Laboratory Methods, 22nd Ed. R.A. McPherson and M.R. Pincus, eds. Elsevier Saunder. 2011.
  3. B.A. Runyon. Ascitic Fluid Bilirubin Concentration as a Key to Choleperitoneum. J. Clin. Gastroentorol 9(5):543-545. 1987.

CPT Codes

82042 (Albumin), 82150 (Amylase), 82247 (Bilirubin, Total), 86301 (CA 19-9), 84311 (Cholesterol), 82570 (Creatinine), 82945 (Glucose), 83615 (LD), 83986 (pH) 84157 (Protein, Total), 84478 (Triglycerides).

LOINC: 12183-0, Albumin-1749-1, Bilirubin-14422-0, Cholesterol 12183-0, Creatinine 12191-3, Lactate Dehydrogenase 14803-1, Triglycerides 14447-7, Peritoneal Fluid 1749-1, 14422-0, pH Fluid 2756-5


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