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UW Health SMPH
American Family Children's Hospital

UW Hospital and Clinics Lab Test Directory

Test Name: Immunofixation Electrophoresis, Urine, 24 Hour

Test Code(s): UIFIX / HCUIFIX

CPT Code(s): 86335, 84156

Test Description: Test Component:

Urine immunofixation and a quantitative urine protein.

Methodology: Gel Electrophoresis

Clinical Significance: Immunofixation is used to test for and classify light chains (Bence Jones protein) in urine. Diseases associated with light chains in urine include gammopathy, amyloidosis, multiple myeloma and other plasma cell dyscrasias.

Days Performed: Mon-Fri, dayshift - day varies.

Turnaround Time: Stat: Not available stat.
Routine: 3 working days.

Specimen Requirements

Specimen: 24 hour timed urine

Collection Instructions: No preservative necessary. For timed urine collections, collect all urine in container provided.  Add "Refrigerate" sticker to 24-hour container.

For 24-hour urine test the collection period must be within 22-26 hours.  Collection period starts after first void of the period.  It is very important to refrigerate specimen during and after the collection.  Indicate the date and time collection started and date and time collection finished.  If questions about collection process or container does not have instructions attached, call (608) 263-7060 for assistance.

Patient instructions available at Search for 24-hour urine collection or UWH#4339.

Collection Container: Preferred: 24 hour urine container

Collection Volume: Preferred: Entire collection
Pediatrics: Entire collection

Sample Analyzed: Urine aliquot

Volume Required: Preferred: 10 mL
Pediatrics: 10 mL

Specimen Transport: Immediately after specimen collection is completed, transport specimen to UWHC Core Laboratory (B4/220). If transport is delayed, refrigerate specimen.

Outreach Specimen Transport: Mix urine well and note volume and period.  Transport 50 mL aliquot on coolant pack to UWHC Core Laboratory (B4/220) along with volume and period information.

Unacceptable Criteria: Urines with bloody supernatants are acceptable but not desireable.

Urines with preservatives are not acceptable.

Stability: Ambient: Not acceptable
Refrigerated: 1 week
Frozen: 3 months for concentrated sample


A written interpretive report is issued as a separate report.

Additional Information:

A professional fee is associated with this test.

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