Sign in →

Test Code AFSD AFB Studies, TB

Infectious

Additional Codes

      Acid-Fast Bacilli (AFB)

      AFB (Acid-Fast Bacilli)

      Bacillus, Acid-Fast

      Culture, TB (Tuberculosis)

      MTB (Mycobacterium tuberculosis)

      Mycobacteria Culture

      Mycobacterium tuberculosis (MTB)

      TB (Tuberculosis)

      TB (Tuberculosis) Culture

      Tuberculosis (TB)

Performing Laboratory

YRMC Laboratory, Microbiology Department

Blood Cultures for Myocbacteria are performed by Mayo Medical Laboratories

Day(s) Test Set Up

Monday through Friday

Specimen Requirements

All specimens must be submitted in a leak-proof container and sealed in a biohazard bag.  Specimens that are received leaking or spilled will be rejected for testing.

 

Submit only 1 of the following specimens - specimen source is required:

 

Abscess

Container/Tube: Sterile, screw capped container or syringe with needle removed. Needle may be replaced with sterile syringe cap or sterile capped blunt cannula. Specimens submitted on swabs are sub-opitmal for Mycobacterial culture and do not typically yield productive growth of Mycobacteria.

Specimen Volume: 1-2 ml. aspirate material or abscess drainage.

Collection Instructions:

1. For most open lesions and abscesses, remove the superficial flora by decontaminating the skin before collecting a specimen from the advancing margin or base. 

2. A closed abscess is the specimen site of choice.  Aspirate the abscess contents with a syringe and submit the specimen in a the syringe or expell the contents into a sterile, screw capped container.

3. Please indicate on the request or order if Mycobacterium marinum infection is suspected. This organism requires specialized processing and incubation requirements for optimal recovery.

Note: 1. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection and collector’s initials and or ID number.
2. Specimen source is required.
 
Blood
Container/Tube:
Two, 7-mL green-top (sodium or lithium heparin) tubes-Plasma gel tube is not acceptable.
Specimen Volume:
10 mL of whole blood
Collection Instructions: Do not centrifuge or refrigerate. Collect specimen as follows:
1. Apply tourniquet to patient’s arm.
2. Palpate area to locate vein.
3. Thoroughly cleanse venipuncture site with 70% alcohol moving in concentric circles to periphery. Do not palpate vein after sterilizing area. If site must be touched during venipuncture, disinfect gloved finger. Allow to dry.
Note: 1. Label tubes with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of of collection and collector’s initials and or ID number.
2. Specimen source is required.
 

Bronchial Wash/Bronchial Lavage

Container/Tube: Aspirate trap. Attach the tubing firmly to the top of the aspirate trap to ensure the specimen does not leak during transport. Do not add cytology preservative(CytoLyt®)  to specimens submitted for culture.

Specimen Volume: Minimum volume: 7.5 ml

Collection Instructions: Collect per established bronchoscopy protocol.

Note: 1. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection and collector’s initials and or ID number.

2. Specimen source is required.


Body Fluid
Container/Tube:
Screw-capped, sterile container, evacuated collection contaimer. Specimens submitted on swabs are not acceptable.
Specimen Volume: 5 mL of body fluid
Collection Instructions: Collect aseptically. Disinfect site with alcohol if collecting by needle and syringe.
Note: 1. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection and collector’s initials and or ID number.
2. Specimen source is required.

 

Gastric Aspirate

Container/Tube: Sterile, screw capped container or aspirate trap. Attach the tubing firmly to the top of the aspirate trap to ensure the specimen does not leak during transport.

Specimen Volume: 5 – 10 ml gastric aspirate.

Collection Instructions: Collect per established gastric aspiration protocol.

Note:

1. Gastric aspirates are often the preferred specimen for diagnosing Myocbacterium tuberculosis in pediatric patients.

2. Aspirate specimens for AFB culture should be collected after the patient has had at least 6 hours of un-interrupted sleep and has been fasting for at least 6 hours.

3. Do not use any NG tube lubricant. All lubricants are bacteriostatic.

4. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection and collector’s initials and or ID number.

5. Transport the specimen to the Microbiology department without delay.

6. Specimen source is required.

 
Sputum, Expectorated
Container/Tube: Screw-capped, sterile container.
Specimen Volume: Expectorated sputum (minimum volume: 5 mL). Regulating bodies (CDC, WHO, APHL) recommend a series of at least 3 sputum specimens collected 8 to 24 hours apart with at least one early morning sputum specimens for tuberculosis rule out.


Collection Instructions: Collect specimen as follows:
1. Have patient remove dentures, if applicable.
2. Instruct patient to brush his/her teeth and/or rinse mouth well with water to minimize contaminating specimen with food particles, mouthwash, or oral drugs which may inhibit growth of mycobacteria.
3. Instruct patient to take a deep breath, hold it momentarily, then cough deeply and vigorously into container.

 

Nasal secretions or saliva are not acceptable specimens.
Note:
1. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection and collector’s initials and or ID number.

2. Specimen source is required.
 
Sputum, Induced
Container/Tube: Screw-capped, sterile container(s) or aspirate trap. If an aspirate trap specimen is submitted, attach the tubing firmly to the top of the aspirate trap to ensure specimen does not leak during transport.
Specimen Volume: Early-morning induced sputum (minimum volume: 5 mL) Regulating bodies (CDC, WHO, APHL) recommend a series of at least 3 sputum specimens collected 8 to 24 hours apart with at least one early morning sputum specimens for tuberculosis rule out.


Collection Instructions: Induce cough by inhalation of sterile, hypertonic saline, and collect expectorated material. Avoid sputum contamination with nebulizer reservoir water.
Note: 1. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection, and collector’s initials and or ID number.
3. Specimen source is required.
 
Tissue
Container/Tube:
Screw-capped, sterile container(s) without fixative or preservative-Specimen in formalin is not acceptable.
Specimen Volume:
1 g of tissue, if possible
Collection Instructions: Collect aseptically avoiding indigenous microbiota. Select caseous portion if available. Do not immerse in saline or other fluid or wrap in gauze.
Note: 1. Label container with patient’s name (first, last, and middle initial), medical record number, date of birth, date and time of collection and collector’s initials and or ID number.
2. Specimen source is required.
 
Urine
Container/Tube:
Screw-capped, sterile container(s)
Specimen Volume: 30 mL to 50 mL from a random urine collection
Collection Instructions:
Note: 1. Label container with patient’s name (first, last, and middle initial), medical record number (if appropriate), date of birth, date and time of collection and collector’s initials and or ID number.
2. Specimen source is required.

Specimen Transport Temperature

Ambient

Refer to Microbiology Special Instructions for specimen stability.

Reference Values

Negative for AFB at 6 weeks

Test Classification and CPT Coding

87116 - AFB Culture

87206 - AFB Smear

87015 - Concentrate, AFB (specimen dependent)

Testing Algorithm

1. Testing includes a culture and an AFB smear for all specimens submitted except Blood Cultures for AFB.

2. Specimens submitted for AFB culture and smear are processed Monday through Friday.

3. AFB Smears are available Sunday through Saturday upon STAT request. For specimens that require digestion/decontamination (ie: respiratory specimens and those specimens typically contaminated with indiginous flora), direct AFB smears will be prepared and reported for STAT requests. All specimens that received a STAT direct AFB smear will receive a follow-up concentrated AFB smear.

Methodology

Conventional Acid Fast Bacillus culture methods including liquid (volume dependent) and solid culture media.

Includes Acid Fast Bacillus smear.

Loinc Code

543-9