Lab Test

Crystals in Synovial Fluid

Synovial Fluid Analysis

Test Codes




Specimen Collection Criteria

Collect: 1.0 mL synovial fluid in a Green-top Sodium Heparin tube (Minimum: 0.5 mL) or sterile cup.

  • Crystal identification should not be performed on Lavender-top EDTA tubes, as powdered EDTA may produce false positive results.
  • Specimens collected in Red-top tubes are no longer acceptable.

Physician Office/Draw Specimen Preparation

Arrange for transportation to the Laboratory prior to specimen collection. Maintain specimen refrigerated (2-8°C or 36-46°F) prior to transport.

Preparation for Courier Transport

Transport: 1.0 mL synovial fluid, refrigerated (2-8°C or 36-46°F). (Minimum: 0.5 mL)

Rejection Criteria

  • Specimens received in bags, bottles, or syringes.
  • Specimens collected in Lavender-top EDTA tubes, Oxalate, Green-top Lithium Heparin tubes, or Red-top tubes.

Inpatient Specimen Preparation

Transport specimen to the Laboratory immediately after collection.


Specimen Stability for Testing:

Room Temperature (20-26°C or 68-78.8°F): 8 hours
Refrigerated (2-8°C or 36-46°F): 24 hours
Frozen (-20°C/-4°F or below): Unacceptable

Specimen Storage in Department Prior to Disposal:

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


Dearborn Hematology Laboratory
Farmington Hills Hematology Laboratory
Grosse Pointe Hematology Laboratory
Royal Oak Hematology Laboratory
Taylor Hematology Laboratory
Troy Hematology Laboratory
Wayne Blood Bank


 Site: Performed:  24-hours a day 
 Farmington Hills Hematology Laboratory   Sunday – Saturday
 Grosse Pointe Hematology Laboratory Sunday – Saturday
 Royal Oak Hematology Laboratory Sunday – Saturday
 Troy Hematology Laboratory Sunday – Saturday
 Performed:  Day Shift Only
 Dearborn Hematology Laboratory Monday –Saturday
 Taylor Hematology Laboratory Monday – Friday
 Wayne Hematology Laboratory Monday – Friday
 Canton Laboratory 
 Lenox Laboratory 
 Trenton Laboratory 
 Livonia Laboratory 


Reference Range


Test Methodology

Polarizing Microscope.


The presence of monosodium urate crystals is usually diagnostic of gout. The presence of calcium pyrophosphate dihydrate crystals is characteristic of "CPPD crystal deposition disease" or pseudogout.

Clinical Utility

This test can assist in the diagnosis of gout, pseudogout, and other arthritic diseases. The types of crystals found in synovial fluid include monosodium urate, calcium pyrophosphate dihydrate, cholesterol, or steroid.

CPT Codes



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