Acid-Fast Smear for Mycobacterium

Useful for the diagnosis of mycobacterial disease and to monitor the course of antimycobacterial therapy. When ordering #416 Culture, Mycobacterium, this test will automatically be ordered. For monitoring therapy, a stain alone may be sufficient. 

1. All specimen types should be collected prior to initiation of antimycobacterial chemotherapy.
2. Avoid contamination with tap water or other fluids that may contain environmental mycobacteria, since saprophytic mycobacteria may produce a false-positive culture and/or smear results.
3. Do not use any fixatives or preservatives.
4. See individual specimen types for detailed instructions.

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Submint only one of the following specimens:

Blood
Container/Tube: Wampole Isolator 10-mL tube(s)
Specimen Volume: Full tube of blood
Collection Instructions:
1. Obtain Wampole Isolator 10-mL tube for each set of Mycobacterium cultures ordered.
2. Always draw Mycobacterium blood cultures before other specimens.
3. Disinfect tube stopper with 10% polyvinyl alcohol iodine. Do not allow iodine to pool on stopper. Iodine could enter tube and kill organisms in specimen. 4. Allow to dry completely for about 1 minute.
5. Disinfect venipuncture site with alcohol and iodine. Allow iodine to dry.
6. Draw specimen directly into Wampole Isolator 10-mL tube.
7. Immediately after draw, invert 4 to 5 times to mix blood with contents of Wampole Isolator 10-mL tube. Incomplete mixing will cause small clots to form and patient must be redrawn.
8. Label tube with patient’s name (first and last) and date and actual time of collection.
Note: Specimen source is required.

Gastric Content
Container/Tube: Sterile container(s)
Specimen Volume: Gastric content
Collection Instructions:
1. Gastric content is acceptable when sputum specimens are unavailable (often used in young children).
2. Collect specimen in the early-morning before food and water intake, in a sterile container.
3. Label container with patient’s name (first and last) and date and actual time of collection.
Note: Specimen source is required.

Sputum
Container/Tube: Sterile container(s)
Specimen Volume: 5 mL to 10 mL of discharged material
Collection Instructions:
1. Collect a fasting, early-morning specimen on at least 3 consecutive days as follows:
      A. Instruct patient to brush his/her teeth and/or rinse mouth well with water to minimize contaminating specimen with food particles, mouthwash, 
       oral drugs which may inhibit the growth of mycobacteria. 
      B. Have patient remove dentures.
      C. Instruct patient to take a deep breath, hold it momentarily, then cough deeply and vigorously into container.
2. Label tube with patient’s name (first and last) and date and actual time of collection.
Note: Specimen source is required.

Stool
Container/Tube: Sterile container
Specimen Volume: 2 g to 3 g of stool
Collection Instructions:
1. Stool specimen is recommended only for detection of Mycobacterium avium complex involvement in gastrointestinal tracts of patients with autoimmune deficiency syndrome.
2. Label container with patient’s name (first and last) and date and actual time of collection.
Note: Specimen source is required.

Urine
Container/Tube: Sterile container(s)
Specimen Volume: 50 mL from a first-morning, random urine collection
Collection Instructions: Label container with patient’s name (first and last) and date and actual time of collection.
Note: Specimen source is required.

Ambient

Monday through Sunday

Negative (reported as positive or negative)
Critical value (automatic call-back): all positives
Cultures are more sensitive than smears. Therefore, the smear may be negative when the culture is positive. Any positive smears are called back immediately.