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Mycobacteria (including TB) Culture



Diagnosis of Tuberculosis (TB) and other Mycobacterial infections


Respiratory Specimens (e.g. Sputum, BAL/BW, Pleural fluid)

Tissues & Fluids (e.g. Pus, Bone Marrow, CSF, Skin Biopsy)

Urine (Whole Early morning Urine) – Requests should be discussed with a Consultant Microbiologist before sending

Blood culture – Please see Mycobacterial Blood Culture page for more information

NB: Swabs are not suitable for Mycobacteria culture. These samples will be rejected. Please send Pus, Tissue or Fluid.

Specimen container

Sputum Pot                                                                      White Top Universal Tubes

Plain 24 hour Urine container – 1 litre volume (Please request from Pathology Stores)

To Request On EPIC

For electronic requesting using EPIC (RDUH ONLY):

Search for: ‘TB & Mycobacteria‘ or test code ‘LAB877

Special Instructions


  • Please send separate specimens please for TB and “routine” culture
  • Send three separate specimens; preferably early morning on successive days if TB is suspected

Whole Early morning Urine – Requests should be discussed with a Consultant Microbiologist before sending 

For Renal / Bladder TB, specimens should be taken before anti-tuberculosis therapy is started. Samples should be collected in the early morning on 3 consecutive days. The WHOLE first pass urine sample (ie not just 10mL) should be collected in a plain Urine container, and sent top Microbiology lab. Containers are obtained from Path Stores (01392 402906). (NB this is a smaller bottle than the Biochemistry 24 hour urine collection pot)

All Specimens

  • Please use risk of infection stickers
  • Please full clinical details for specimens other than sputum. E.g. CSF, Skin Biopsy/Tissues
  • Please state if this is a follow up sample from a previous positive. If yes, please give details of previous positive
  • Please state if the patient is on Anti-TB therapy
  • Bronchial Washings should not be repeated under 45 hours


Initial Microscopy and Culture performed at RD&E

Positive cultures referred to Reference Laboratory for confirmation, formal identification (& sensitivities if appropriate.)

Reference Laboratory

Wales Centre for Mycobacteria (Cardiff) – Public Health Wales (PHW)

Turnaround Time

Auramine Phenol Stain for AFB – within 3 days

Liquid culture – up to 6 weeks (for a negative result)

Solid culture – up to 12 weeks

Urgent Specimen Intructions

Please phone laboratory if urgent smear required

Useful Links

For Patients:

AFB Testing – Lab Tests Online UK

Tuberculosis – Lab Tests Online UK

Non-tuberculous (Atypical) Mycobacterium – Lab Tests Online UK

For Healthcare Professionals:

British Thoracic Society Guidelines

Wales Centre for Mycobacteria (WCM) – Public Health Wales

(Key words: AFB)

Specimen Labelling Procedure
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