Sample type: Serum

Test name: Rifabutin

Condition / Indication: Requesters have found these assays to be of value in patients receiving agents that have known drug interactions with Rifabutin (such as clarithromycin, a number of antifungal agents and many of the antiviral agents used to treat HIV infection) and in cases of suspected toxicity.

Advance warning: Not normally required during our core working hours (Mon – Fri 09:00 – 17:15). Please contact laboratory to discuss the possibility of this assay being performed on Saturdays, 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 <3 days. 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 three post dose samples, taken 1 hour, 2 hours and 4 hours after oral administration.

Test information required: • Patient name, sex and age
• Laboratory number
• Dosage, frequency and timing of samples
• Clinical Summary
• Other medications (essential)
• 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 9am and 3pm Monday to Friday. A written confirmation report will be sent by post.

Reference range: Pre dose <0.1 mg/L
Post dose 0.45-0.9 mg/L

Container: Serum (Gold top)

Referred outside NBT for analysis? No

Discipline: Antimicrobial Reference Laboratory

Turnaround time: <3 days

Re-assay interval: Depending on concentrations & patient progression.