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Lab Dept:
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Other Fluids
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Test Name:
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IGG INDEX, CSF
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General Information
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Lab Order Codes:
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IGGI
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Synonyms:
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Cerebrospinal Fluid (CSF) IgG Index
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CPT Codes:
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82040 – albumin, serum
82042 – albumin, urine or other source, quantitative
82784 x2 – gammaglobulin; IgG, each
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Test Includes:
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IgG synthesis rate CSF. Both CSF and serum are required for this test.
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Logistics
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Test Indications:
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The CSF index is useful in the diagnosis of individuals with multiple sclerosis.
The index is independent of activity of the demyelinating process
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Lab Testing Sections:
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Chemistry - Sendouts
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Referred to:
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Mayo Medical Laboratories (Test# 8009)
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Phone Numbers:
Minneapolis:
Saint Paul:
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612-813-6280
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651-220-6550
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Test Availability:
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Daily, 24 hours
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Turnaround Time:
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1 - 3 days, test set up Monday - Saturday
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Special Instructions:
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N/A
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Specimen
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Specimen Type:
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Both serum and spinal fluid are required for this test and must be obtained within 24 hours of each other
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Container:
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Blood: Red top tube
CSF: Screw capped, sterile vial
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Draw Volume:
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3.0 mL blood
1.0 mL CSF
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Processed Volume:
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1.0 mL (Minimum: 0.5 mL) serum and 1.0 mL (Minimum: 0.5 mL) spinal fluid
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Collection:
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Routine venipuncture and spinal fluid collection
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Special Processing:
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Lab Staff: Centrifuge blood specimen, remove serum aliquot and refrigerate in a plastic screw-top vial. Aliquot CSF into a plastic screw-top vial and refrigerate. Label specimen source appropriately on each tube. Send at refrigerated temperatures. Forward promptly.
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Patient Preparation:
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None
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Sample Rejection:
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N/A
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Interpretive
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Reference Range:
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CSF index:
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≤0.85
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CSF IgG:
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≤8.1 mg/dL
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CSF albumin:
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≤27.0 mg/dL
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Serum IgG:
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600 - 1500 mg/dL
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Serum albumin:
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3200 - 4800 mg/dL
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CSF IgG/albumin:
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≤0.21 mg/dL
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Serum IgG/albumin:
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≤0.4 mg/dL
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CSF IgG synthesis rate:
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≤12 mg/24 hours
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Critical Values:
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N/A
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Limitations:
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The CSF index can be elevated in other inflammatory demyelinating polyradiculoneuropathy, and subacute slerosing panencepahlaitis.
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Methodology:
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Nephelometry
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Contraindications:
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N/A
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References:
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Mayo Medical Laboratories Web Page December 2006
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