Test directory: Acid Fast Smear and Culture

Ordering Code651
Test NameAcid Fast Smear and Culture
AliasAFB Smear and Culture
Mycobacteria Smear and Culture
TB Smear and Culture
MAI Smear and Culture
NTM Smear and Culture
Preferred SpecimenLower Respiratory Specimens (Expectorated Sputum, Tracheal
Aspirate, Bronchial Wash or Lavage, Bronchial Brush) in
Sterile Container, Urine in Sterile Container, Stool in
Clean Container, Gastric Aspirate in Sterile Container
Other Specimen/ContainerCulture swabs (e.g. Eswab) will be accepted but is not an appropriate collection container due to suboptimal volume
If available, tissue and/or fluid (order code 651S) are superior to swabs for culture.
Optimum VolumeGastric Aspirate: 5 mL
Urine: 50 mL
Stool: 5 g
Lower Respiratory Specimens: 5 mL
Collection InstructionsUrine: First morning, clean catch, mid-stream specimen is preferred
Lower Respiratory Specimens: First morning sputum (not saliva) from three separate days are recommended.
Handling InstructionsGastric Aspirate:
Specimen should be neutralized as soon as collected: 1. Add 50 to 100 mg Sodium Carbonate powder to 50 mL gastric lavage; replace and tighten the cap. Mix by vortexing
2. Centrifuge at 3000 G for 15 minutes
3. Pour off supernatant fluid and resuspend sediment in 2 to 5 mLs for sterile distilled water
4. Add an equal amount of 4% NaOH. Vortex well and let stand for 15 minutes

Lower Respiratory Specimens:
Refrigerate as soon as possible. Add sterile normal saline to Bronch Brushings to prevent drying. Allow any slides made at the time of collection to air dry thoroughly before placing in slide holders, Bronchial Brushing slides should be sent separately from the washes and kept ambient.
Transport RequirementsOahu: Refrigerated
Airline: Refrigerated
Specimen StabilityAmbient: 2 Hours
Refrigerated: 5 Days
Rejection CriteriaFrozen, Pooled specimen, Preservatives used, Specimen older than stability limits
Avail. StatNO
Analytic Time8 Weeks
Smear result available within 24 hours. Positive cultures reported as soon as detected. Additional time is required for ID/susceptibility if culture is positive.
MethodologyGrowth detection by CO2 production of acid-fast organism & microscopic examination of Fluorescent/Carbol Fuchsin stained smear

Reference range(s)

ComponentAgeMale NormMale Critical LowMale Critical HighFemale NormFemale Critical HighFemale Critical LowUnitsAdd'l info
Site:ALLSee report.
Acid Fast Smear:ALLSee report.
AFB Culture Status:ALLSee report.
AFB Culture:ALLSee report.