| Ordering Code | 651 |
|---|---|
| Test Name | Acid Fast Smear and Culture |
| Alias | AFB Smear and Culture Mycobacteria Smear and Culture TB Smear and Culture MAI Smear and Culture NTM Smear and Culture |
| Preferred Specimen | Lower 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/Container | Culture 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 Volume | Gastric Aspirate: 5 mL Urine: 50 mL Stool: 5 g Lower Respiratory Specimens: 5 mL |
| Collection Instructions | Urine: First morning, clean catch, mid-stream specimen is preferred Lower Respiratory Specimens: First morning sputum (not saliva) from three separate days are recommended. |
| Handling Instructions | Gastric 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 Requirements | Oahu: Refrigerated Airline: Refrigerated |
| Specimen Stability | Ambient: 2 Hours Refrigerated: 5 Days |
| Rejection Criteria | Frozen, Pooled specimen, Preservatives used, Specimen older than stability limits |
| Avail. Stat | NO |
| Analytic Time | 8 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. |
| Methodology | Growth detection by CO2 production of acid-fast organism & microscopic examination of Fluorescent/Carbol Fuchsin stained smear |
Reference range(s)
The reference ranges listed below are valid on this date of June 29, 2025.
| Component | Age | Male Norm | Male Critical Low | Male Critical High | Female Norm | Female Critical High | Female Critical Low | Units | Add'l info |
|---|---|---|---|---|---|---|---|---|---|
| Site: | ALL | See report. | |||||||
| Acid Fast Smear: | ALL | See report. | |||||||
| AFB Culture Status: | ALL | See report. | |||||||
| AFB Culture: | ALL | See report. |