Gentamicin Trough

Test Code

LAB26

Alias/See Also

GENT

CPT Codes
80170

Preferred Specimen

" One 4.5ml light green top (heparin) tubeor one 5ml Red/gold top serum separator tube. "

Instructions

"For patients receiving gentamicin via conventional dosing methods peak and trough drug monitoring should begin after a steady state is achieved (usually after 3–4 doses). Samples for trough concentrations should be collected 15 minutes prior to the next scheduled dose."

Specimen Stability

Refrigerate, stable 48 hours; stable 8 hours at room temperature; stable 6 months if frozen.

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

Insufficient quantity; failure to follow stability requirements

Methodology
Two point rate: The assay is based on competition between gent. in thesample and gentamicin labeled with G6P-DH for antibody binding sites.

Setup Schedule

Daily/STAT

Report Available

"Within 24hrs
STAT:1hr sfter collection"

Reference Range

"0.0-2.0 ug/mL
Critical Value: >2.1 ug/mL"

Clinical Significance

Gentamicin is safe and effective only in a narrow range of concentrations for a given indication. Exposure to high gentamicin concentrations for a prolonged period may cause renal impairment or ototoxicity. Serum or plasma gentamicin measurements are used in the diagnosis and treatment of gentamicin overdose and in monitoring levels of gentamicin to ensure appropriate therapy.

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.