Skip to main content

Mycobacterium (Microscopy & Culture)

Alias: AAFB, TB, Mycobacteria tuberculosis

Discipline: Clinical Microbiology

Test information: The detection and isolation of Mycobacteria species from a variety of clinical samples.

Availability: Available locally Monday - Friday during routine hours: 08:45 - 17:15.

Turnaround Time: 24 hours (Microscopy)
6 Weeks (Culture)

Related Tests: QuantiFERON-TB Gold PLUS

Specimen Type(s)
  • Blood;
  • Bone Marrow;
  • Bronchial washings;
  • Bronchoalveolar Lavage;
  • Cerebrospinal fluid;
  • Early Morning Urine;
  • Lymph Nodes;
  • Pericardial fluid;
  • Pleural fluid;
  • Post-Mortem Specimens;
  • Respiratory Empyema Pus;
  • Skin Swab;
  • Sputum;
  • Tissue;
  • Tissue Biopsies;
Other Acceptable Specimen Type(s)
Gastric aspirates and faecal specimens are not routinely tested for mycobacterium - contact the laboratory before submitting specimens.
Specimen Container - Adult
  • Green Top BD;
  • Sterile CE-marked Universal Container;
Specimen Container - Paediatric
  • Light Green Top Microtainer BD;
  • Sterile CE-marked Universal Container;
  • Microscopy & Culture;
  • Mycobacterium species ;
Part of a test profile?
Volume (min) of sample to be sent to laboratory
Sputum: >5mL
Urine: 200mL
Patient Preparation, Sample Handling and Transport
  • For initial diagnosis of mycobacterial infection all specimens should be fresh and taken when possible before anti-tuberculous treatment is started.
  • Sputum specimens should be less than 1 day old to minimise contamination. Two to three samples should be collected approximately 8-24 hours apart with at least one from early morning. Specimens collected on 3 consecutive days should not be pooled.
  • Sputum should be expectorated from the lower respiratory tract by deep coughing. When the cough is dry, physiotherapy, postural drainage or inhalation of nebulised saline before expectoration may be helpful.
  • Urine specimens should be collected separately in the early morning on three consecutive days in a 250mL CE-marked leak proof container (which does not contain boric acid).
  • When collecting BAL/bronchial washings, avoid contaminating bronchoscope with tap water, which may contain environmental Mycobacterium species.
  • For Mycobacterium avium disseminated infection please submit a blood sample in a lithium heparin tube on three consecutive days requesting MAI investigation.
  • For blood and bone marrow, the skin should be disinfected at the venepuncture site and allowed to dry. Withdraw sufficient blood to fill a green top lithium heparin vacutainer blood tube. EDTA is inhibitory to Mycobacterium species, even in trace amounts.
  • Skin/tissue biopsy/post-mortem specimens should be collected aseptically into a container without preservatives. The majority of organisms will be found in the periphery of a caseous lesion.
  • Please mention contact with water from fish tanks, swimming pools and natural areas of fresh or salt water to ensure investigation for Mycobacterium marinum.
  • Specimens should be transported to the laboratory without delay during normal working hours.
  • Specimens other than blood should be stored at 2-8 °C if transport to the laboratory is delayed for more than 1hour.
Maximum add on time
Units and Reference Ranges / Interpretation
UKAS number
UKAS accredited test?

If you have any queries about a test or results interpretation please contact us.

Last updated: 01-06-2023