Gentamicin, Peak and Trough

Test Code

444

CPT Codes
80170 (x2)

Preferred Specimen

1 mL serum collected in each of two separate red-top tubes (no gel)

Patient Preparation
Collect peak at the end of 60 minute IV infusion, 30 minutes after the end of 30 minute IV infusion or 60 minutes after the IM dose.
Collect as a trough just before next dose.

Minimum Volume

0.2 mL

Other Acceptable Specimens

Plasma collected in each of two tubes: EDTA (lavender-top), or lithium heparin (green-top), or sodium heparin (green-top)

Transport Temperature

Room temperature

Specimen Stability

Room temperature: 5 days
Refrigerated: 7 days
Frozen: Unacceptable

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Serum separator tube (SST)

Methodology
Immunoassay (IA)

Setup Schedule

Set up: Mon-Sat; Report available: 1-2 days

Reference Range

Gentamicin, Peak	5.0-10.0 mg/L
Gentamicin, Trough	1.0-2.0 mg/L

Clinical Significance

Gentamicin is an aminoglycoside antibiotic used in the treatment of gram positive and gram-negative bacterial infections, especially Pseudomonas, Proteus, Klebsiella and Staphylococcus. Gentamicin is potentially nephrotoxic and ototoxic and serial monitoring of peak and trough serum levels may provide the clinician with information to maintain safe and therapeutic levels.

Performing Laboratory
Quest Diagnostics Nichols Institute
14225 Newbrook Drive
Chantilly, VA 20153

The CPT Codes provided in this document 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 payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.