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ID:585 Alcohol and acid fast bacilli (AAFB) culture - BAL for pulmonary TB
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Description85% of clinical tuberculosis presents as pulmonary tuberculosis. Identification of the presence of mycobacteria provide diagnosis and treatment options. Initial indication of infection may be the identification of AAFB by microscopy. Culture for AAFB in the laboratory uses continuous automated bacterial culture but can take up to 8 weeks. Further identification and susceptibility testing are provided following referral to Birmingham PHL laboratory (currently the referral lab is not accredited for this test)
IndicationPatients who are too unwell to cough or have a peripheral lesion on the chest x-ray may benefit from a BAL.
Additional InfoPlease remember that tuberculosis is notifiable even on grounds of clinical suspicion alone. Selected patients might benefit from TB PCR which requires prior discussion with the microbiologist before testing.
Concurrent Testsna
Dietary Requirementsna
InterpretationPreliminary microscopy results will be reported negative or positive with a quantitative indication. Initial culture results will be reported as AAFB isolated with confirmation of final identification and sensitivities reported later.

SampleBAL Fluid
TubePlain Universal
Tube Picture
Collection ConditionsFor initial diagnosis specimens should be fresh and where possible taken before anti-tuberculous treatment started. Other broad spectrum antibiotics such as fluoroquinolones or macrolides may also exhibit anti-mycobacterial activity so should ideally be avoided for at least 48 hours preceding specimen collection. Performing a procedure for BAL collection for TB should be performed in a room with appropriate respiratory isolation ventilation conditions and staff should wear FFP3 masks. Careful cleaning of instruments is required to prevent cross contamination of specimens or patients. Tap water should not be used as this may contain environmental mycobacteria species which can produce false positive results. Please request clearly AAFB culture and microscopy on form. Samples should be marked as Danger of Infection. Do not send samples for AAFB via the airtube
Min. Vol10 - 20 mL
Freq.1 sample per affected bronchus

Ref. Range (Male)
Ref. Range (Female)
Ref. Range (Paed)
Ref. Range Notes
Units - Not Defined -
IP Acute TATSee Turnaround Comment
IP Routine TATSee Turnaround Comment
GP Acute TATSee Turnaround Comment
GP Routine TATSee Turnaround Comment
Turnround CommentMicroscopy for AAFB will be available within 24 hours for samples received Monday to Friday before 12pm. Microscopy TAT for samples received at weekends and bank holidays will be 3 days. Culture 60 days Turnaround time may be increased if prolonged incubation is clinically indicated.

Originally edited by : Dr. H. Schuster. Review due on 14/11/2018 14:56:55. Published By K Roberts on 14/11/2017 14:56:55.