CTB - Specimen: Mycobacteria and Nocardia Culture

Test Catalog

Test Name

Test ID: CTB    
Mycobacteria and Nocardia Culture

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

When this test is ordered, a reflex test may be performed and charged.

 

See Mycobacterial Culture Algorithm in Special Instructions.

Specimen Type Describes the specimen type validated for testing

Varies

Necessary Information

1. Specimen source is required.

2. Alert the laboratory if Mycobacterium genavense is suspected, as this species requires addition of mycobactin J to the culture medium for optimal growth and recovery.

Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.

Submit only 1 of the following specimens:

 

Specimen Type: Body fluid

Container/Tube: Sterile container

Specimen Volume: 1 mL

 

Specimen Type: Bone marrow

Container/Tube: SPS/Isolator System or green top (lithium heparin)

Specimen Volume: Entire collection

 

Specimen Type: Gastric washing

Container/Tube: Sterile container

Specimen Volume: 10 mL

Collection Instructions: Neutralize specimen within 4 hours of collection with 100 mg of sodium carbonate per 5 to 10 mL of gastric wash.

 

Specimen Type: Respiratory

Sources: Bronchoalveolar lavage fluid, bronchial washing, sputum

Container/Tube: Sterile container

Specimen Volume: 3 mL

Collection Instructions:

1. Collect 3 respiratory specimens for acid-fast smears and culture in patients with clinical and chest X-ray findings compatible with tuberculosis.

2. These 3 specimens should be collected at 8- to 24-hour intervals (24 hours when possible) and should include at least 1 first-morning specimen.

 

Specimen Type: Stool

Supplies: Stool Collection Kit, Random (T635)

Container/Tube: Sterile container

Specimen Volume: 5-10 g

 

Specimen Type: Tissue

Container/Tube: Sterile container

Specimen Volume: 5-10 mm

Collection Instructions: Collect a fresh tissue specimen.

 

Specimen Type: Urine

Container/Tube: Sterile container

Specimen Volume: 2 mL

Collection Instructions: Collect a random urine specimen.

 

Fresh tissue or body fluid is the preferred specimen type instead of a swab specimen.

Specimen Type: Swab

 

Sources: Wound, tissue, or body fluid

Container/Tube: Culture transport swab (noncharcoal) culturette

Specimen Volume: Adequate specimen

Collection Instructions:

1. Before collecting specimen, wipe away any excessive amount of secretion and discharge, if appropriate.

2. Obtain secretions or fluid from source with sterile swab.

3. If smear and culture are requested or both a bacterial culture and mycobacterial culture are requested, collect a second swab to maximize test sensitivity.

Forms

If not ordering electronically, complete, print, and send 1 of the following forms with the specimen:

Microbiology Test Request Form (T244) (http://www.mayomedicallaboratories.com/it-mmfiles/microbiology_test_request_form.pdf)

General Request Form (T239) (http://www.mayomedicallaboratories.com/it-mmfiles/general-request-form.pdf)

Specimen Minimum Volume The amount of sample necessary to provide a clinically relevant result as determined by the Laboratory.

Varies; Body Fluid: 1.5 mL; Respiratory Specimen: 3 mL; Fresh Tissue: pea-sized piece

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected

Hemolysis

NA

Lipemia

NA

Icterus

NA

Other

Blood or fixed tissue; specimen in viral transport medium (including but not limited to M4, M5, BD viral transport media, thioglycolate broth); swab sources of nasal, sinus, ear, mouth, throat, or scalp; wood shaft or charcoal swab, petri dish

Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperatures are also included.

Specimen TypeTemperatureTime
VariesRefrigerated (preferred)7 days
 Ambient 7 days