Specimens should be delivered to the microbiology laboratory as soon as possible. Do not freeze specimens at -20C, or in a frost-free freezer. Specimens should be collected in sterile leakproof containers without preservatives. A sterile anticoagulant such as heparin or SPS may be used in collection tubes to prevent clots in body fluids. Swab-collected specimens and fecal specimens are NOT recommended.
See eSwab collection video for more information
For sputum, three samples are recommended (one early morning from deep cough or expectorated sputa induced by aerosolization) eight to twelve hours apart. For urine, three specimens, one per day for three consecutive days are recommended. For gastric lavage fluid, three early morning specimens collected on separate days are recommended. Volumes >15 mL will NOT be accepted. For blood and bone marrow AFB culture, see Culture, Acid Fast Bacteria, Blood.
The mycobacterial load in a clinical specimen may be low. Specimens with less than the recommended volumes may therefore lead to a false negative result. Prior antimycobacterial therapy or an inadequate volume of specimen may impact correlation of positive smears with positive cultures. Isolates will receive susceptibility testing only upon provider's request.
Cocentrated/unconcentrated specimen negative for acid-fast bacilli
Culture negative for acid-fast bacilli