Levetiracetam, Immunoassay

CPT Code: 80177
Order Code: 36330
ABN Requirement: No
Alternative Name(s): Keppra, Spritam
Specimen
: Serum, Red Top (no gel) tube
Volume:  1.0 mL
Minimum Volume:  0.5 mL
Container: Red Top (no gel) tube

Collection:

Serum:

  1. Collect and label sample according to standard protocols.
  2. Gently invert tube 5 times immediately after draw. Do not shake.
  3. Allow blood to clot 30 minutes.
  4. Centrifuge specimen for 10 minutes.
  5. Aliquot serum into transport tube labeled as “Red Top Serum”. Discard original tube.

Patient Preparation: Brivaracetam (Brivact®, Rikelta®) exhibits significant cross-reactivity with the levetiracetam (Keppra®, Spritam®) immunoassay. If Brivaracetam has been prescribed, order send-out test for Levetiracetam by LC/MS/MS (test code 15142).

Optimum Time to Collect Sample: 0.5 to 1 hour pre-oral dose, collect trough at steady state (2 weeks after onset of treatment).

Transport: Store red top serum at 2°C to 8°C after collection and ship the same day per packaging instructions included with the provided shipping box.

Stability:

Ambient (15-25°C): 7 days
Refrigerated (2-8°C):
21 days
Frozen (-20°C):
30 days

Causes for Rejection: Specimens other than red top serum; improper labeling; samples not stored properly; samples older than stability limits; serum separator (SST gel) tube; unspun red top tube

Methodology: Immunoassay

Turn Around Time:  3 to 4 days

Reference Range:

Age Reference Range (mcg/mL)
All 6.0-46.0

Toxic level is not well established. Interpretation should include a clinical evaluation.

Priority Values:

All Ages Priority 2 Value (mcg/mL)
Peak >70.0
Trough >37.0

Clinical Significance: Levetiracetam is currently used as an anti-epileptic drug for treatment of adult partial seizures particularly as an add-on therapy for refractory patients. It also has potential for other anxiety and cognitive disturbances.

The CPT codes provided are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payer being billed.