BUN Creatinine Ratio
Urea/Creatinine Ratio, BUN/Creatinine Ratio
Test Codes
EPIC: LAB5024, Beaker: BCRR, Antrim: 13495
Department
Chemistry
Specimen Collection Criteria
Collect: One Gold-top SST tube. (Minimum Whole Blood: 4.0 mL)
Contact Laboratory for acceptability of other tube types.
See Minimum Pediatric Specimen Requirements for Microtainer® collection.
Physician Office/Draw Specimen Preparation
Let SST specimens clot 30–60 minutes then immediately centrifuge to separate serum from cells. Refrigerate (2–8°C or 36–46°F) the centrifuged SST tube within two hours of collection.
Preparation for Courier Transport
Transport: Centrifuged SST tube, refrigerated (2–8°C or 36–46°F). (Minimum: 0.5 mL)
Rejection Criteria
- Moderate to grossly hemolyzed specimens.
- Red-top tubes with serum not separated from cells within two hours of collection.
In-Lab Processing
Let SST specimens clot 30-60 minutes. Centrifuge SST tubes or Microtainers® to separate serum from cells. Deliver immediately to the appropriate testing station.
Storage
Specimen Stability for Testing:
Centrifuged SST Tubes and Microtainers® with Separator Gel
Room Temperature (20–26°C or 68–78.8°F): 2-4 hours
Refrigerated (2–8°C or 36–46°F): 7 days
Frozen (-20°C/-4°F or below): Unacceptable
Red-top Tubes and Microtainers® without Separator Gel
Room Temperature (20–25°C or 68–77°F): 2–4 hours
Refrigerated (2–8°C or 36–46°F): Unacceptable
Frozen (-20°C/-4°F or below): Unacceptable
Serum Specimens (Pour-Overs)
Room Temperature (20–26°C or 68–78.8°F): 2-4 hours
Refrigerated (2–8°C or 36–46°F): 7 days
Frozen (-20°C/-4°F or below): 7 days
Specimen Storage in Department Prior to Disposal:
Refrigerated (2–8°C or 36–46°F): 7 days
Laboratory
Canton Laboratory
Dearborn Chemistry Laboratory
Farmington Hills Chemistry Laboratory
Grosse Pointe Chemistry Laboratory
Lenox Main Laboratory
Royal Oak Automated Chemistry Laboratory
Troy Chemistry Laboratory
Taylor Chemistry Laboratory
Trenton Chemistry Laboratory
Wayne Chemistry Laboratory
Performed
Sunday – Saturday, 24 hours a day.
STAT results available within 1 hour of receipt in the Laboratory.
Routine results available within 4 hours.
Reference Range
See specific tests for reference range.
This panel includes: BUN and Creatinine.
Test Methodology
Enzymatic Urease, Jaffe, Spectrophotometry.
Interpretation
See specific analytes for interpretation.
This panel includes: BUN and Creatinine.
Clinical Utility
Assessment of renal function. The ratio of BUN to creatinine may also be useful in the following instances:
- A ratio of 10–20 is normal. If BUN and creatinine are elevated, a normal ratio suggests intrinsic renal failure.
- A ratio of greater than 20 suggests prerenal failure or urinary tract obstruction.
CPT Codes
82565, 84520, 3097-3
Contacts
Canton Laboratory – CTN
734-454-8024
Name: Canton Laboratory – CTN
Location:
Phone: 734-454-8024
Chemistry Laboratory – DBN
313-436-2196
Name: Chemistry Laboratory – DBN
Location:
Phone: 313-436-2196
Chemistry Laboratory – FH
947-521-5252
Name: Chemistry Laboratory – FH
Location:
Phone: 947-521-5252
Chemistry Laboratory – GP
313-473-1807
Name: Chemistry Laboratory – GP
Location:
Phone: 313-473-1807
Lenox Laboratory – LNX
947-523-4070
Name: Lenox Laboratory – LNX
Location:
Phone: 947-523-4070
Automated Chemistry Laboratory – RO
248-551-8065
Name: Automated Chemistry Laboratory – RO
Location:
Phone: 248-551-8065
Chemistry Laboratory – TYL
313-295-5360
Name: Chemistry Laboratory – TYL
Location:
Phone: 313-295-5360
Chemistry Laboratory – TRN
734-671-3165
Name: Chemistry Laboratory – TRN
Location:
Phone: 734-671-3165
Chemistry Laboratory – TR
248-964-8070
Name: Chemistry Laboratory – TR
Location:
Phone: 248-964-8070
Main Laboratory –WYN
734-467-4274
Name: Main Laboratory –WYN
Location:
Phone: 734-467-4274
Last Updated
10/3/2023
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