Sample type: Serum

Test name: Tobramycin

Condition / Indication: Requesters have found these assays to be of value in all patients treated for >48 hours and particularly in patients with cystic fibrosis who are receiving tobramycin once a day.

Advance warning: Not usually required during our core working hours (Mon – Fri 09:00 – 17:15) or Sat 09:00-12:00 for this assay. Please contact the laboratory to discuss the possibility of this assay being performed on Sundays and Bank Holidays.

Sample required: Approx. 1-2mL of separated serum (the minimum acceptable is 100µL). Samples may be sent by post. Transport time must be <4 weeks. Samples should be kept at 4°c if there is a delay in sending. Please contact laboratory if in doubt as sample integrity may be affected. Samples must be sealed and packed to conform to current regulations. Leaking samples may not be processed.

Timing of samples: We recommend a pre dose sample and a post dose sample, taken 1 hour after the end of iv/im administration.

Test information required: • Patient name, sex and age
• Laboratory number
• Dosage, frequency and timing of samples
• Clinical Summary
• Address for report
• Phone (fax if preferred) number for report or email address for an electronic copy
• Contact name
• Appropriate hazard warnings

Results: Results will be telephoned/faxed or emailed on the day of receipt for samples received between 9 am and 3 pm Monday to Friday and by 10.00 am on a Saturday. A written confirmation report will be sent by post.

Reference range: Once Daily
Pre dose <1 mg/L and Post dose >10 mg/L or 8 hour post (5 mg/kg) 1.5-6 mg/L or follow Hartford nomogram (but note this is for 7mg/kg)

BD or TDS
Gm – pneumonia

Pre dose <2 mg/L
Post dose 5-10 mg/L
Infective endocarditis (IE)
Pre dose <1 mg/L
Post dose 3-5 mg/L

Container: Serum (Gold top)

Referred outside NBT for analysis? No

Discipline: Antimicrobial Reference Laboratory

Turnaround time: <1 day

Re-assay interval: 3 days - Assuming initial results are within expected range.