TEST DIRECTORY | MIDx Labs

BLOOD UREA NITROGEN (BUN)

Waste product that helps assess kidney function and overall hydration status.

LIS TEST CODE: BUN

CPT CODE: 84520

ALIASES: BUN, Urea

METHODOLOGY: Urease

SPECIMEN:

- Type: Serum

- Container: Gold Top (SST) Vacutainer

- Minimum Volume Required: 1 mL

- Storage/Handling: Allow 30 minutes for blood to clot, then centrifuge specimen at 3500 RPM for 10 minutes. Maintain specimen at room temperature, in the refrigerator, or in the freezer until testing can be performed.

NOTE: If freezing is required to preserve stability, transfer serum into a separate plastic screw-cap transport container.

- Stability:

Room Temperature (20-25 °C): 7 days

Refrigerated (2-8 °C): 7 days

Frozen (-20 °C or colder): 1 year; avoid multiple freeze/thaw cycles.

- Turnaround Time: 24 hours from receipt.

Special Instructions: N/A

REJECTION REASONS: QNS, Gross Hemolysis, Gross Lipemia, Contamination, Stability Violation, Expired Container, Incorrect Container

REFERENCE RANGES:

Males (mg/dL)

1 - 17 years of age: 7 - 20

>= 18 years of age: 8 - 24

Females (mg/dL)

1 - 17 years of age: 7 - 20

>= 18 years of age: 6 - 21