Test Overview
Direct polarized microscopy
Aid in differential diagnosis of gout or pseudogout.
Crystal exam negative (no crystals seen).
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Test Details
24 hours
- Crystal Exam, Synovial Fluid
- Joint Fluid Crystal Exam
- Synovial Fluid Crystal Exam
STAT requests for this test will be performed on a STAT basis (supervisory staff approval is not required).
Specimen Requirements
Collect specimen using aseptic technique. For optimal results, specimen should reach laboratory within 1 hr. of collection.If specimen must be stored, refrigeration is recommended. Specimen must be received within 24 hours of collection.
Send specimen to laboratory within 1 hour of collection.
Additional Information
Test may include pathologist interpretation of results at an additional charge. By ordering this test, the clinician acknowledges that a pathologist interpretation will be performed and billed as a separate additional charge if indicated. Crystals most commonly identified in synovial fluid are negatively birefringent uric acid (gout) and positively birefringent calcium pyrophosphate (pseudogout). Urate crystals are almost always seen intracellularly in acute gout. Calcium pyrophosphate crystals may be detected only after multiple aspirations of affected joints.