Sample preparation for transport
Note: Unless tubes or bottles are commercially prepared with specific preservatives (e.g., for urine or blood), addition of any preservative other than saline can destroy specimen integrity. The following are recommended:
- Swab transport system, Aimes or Stuart's (<1 mL of material; for superficial wounds).
- Anaerobic transport system (<1 mL of aterial
- Sterile cup/container (for tissue, bone, necrotic material or fluid). Note: Large specimens must be cut to appropriate size for grinding and emulsifying.
- Syringes preferred for ~1 mL of aspirated fluid. Note: A large volume is preferred. The lab will centrifuge and process an aliquot.
- Examples of blood-culturing systems: Bactec System, Becton-Dickinson Diagnostic Instrument Systems, Sparks, MD.
- Microscan System, Dade-Behring, Deerfield, IL.
- Vacutainer tubes (Red-top: clotted blood; Green-top: heparinized blood
- Specimens must be submitted in leakproof containers.
- Syringes must be capped with needles removed.
- Paperwork must include patient identification/bar-code information.
- Labels or requisitions that accompany specimens must be contained in separate plastic bags.
- Plain (bare) swabs should be avoided where possible as these permit desiccation of the specimen and the maximum exposure to atmospheric oxygen.
- Commercial anaerobic bag systems are available for transport of specimens thought to be caused by anaerobic microorganism.
- Specimens received in formalin or in EDTA are not acceptable for culture.
The swab system is guaranteed sterile until the seal is broken. Directions for use:
- Peel open and remove the swab from the package.
- Remove the cap/swab stick from the tube.
- Collect the appropriate specimen and put the cap/swab into the tube. Push the cap to bring the swab into contact with the transport medium.
- Print the patient's name and the culture site on the specimen tube.
- Place the specimen in a specimen bag and put the completed test request form in the side pouch.
- Store it at room temperature.
- Send specimen to the laboratory.
A list of common surgical/clinical specimens suitable for culture of bacteria, anaerobes, fungus, and mycobacteria or acid-fast bacillus (AFB) are presented here. Microorganisms that are likely pathogens and those that are likely contaminants are also included.
IDENTIFICATION AND LABELING
Specimen containers must include patient information with to include:
- Source or site
- Date of collection; time of collection; and initials of collector.
- Explicit details of the specimen are required (e.g., exact location, numbered order of sampling).
Whenever possible, cultures should be obtained prior to the administration of antibiotics, especially when suspected organisms are highly susceptible to antibiotics (beta hemolytic streptococci, Neisseria, or Haemophilus influenza). However, specimens should not be rejected on the basis of prior antibiotic administration, as many antibiotics are bacteriostatic, not bactericidal, and the concentration of antibiotic at the site of infection may be below the minimal inhibitory concentration for the organism in question. If the patient is already receiving antibiotics, give RRDA a call prior to sample collection. For some antibiotics, there are enzyme systems we can provide to inhibit the effects of the antibiotic.
The primary objective in the transport of diagnostic specimens is to maintain the samples as near to their original state as possible with minimum deterioration and to minimize hazards to specimen handlers. Adverse environmental conditions (extremes of heat and cold, rapid changes in pressure, or excessive drying) should be avoided.
- All microbiology specimens to be transported through the US mail must be packaged under strict regulations specified by the PHS. Further information is available from CDC.
- Dry ice is considered a hazardous material. Cartons containing dry ice as a refrigerant must be marked "DRY ICE FROZEN MEDICAL SPECIMEN." Packaging should be such at carbon dioxide can escape, preventing a build-up of pressure that could rupture the container.
- The dry ice should be placed outside the secondary container along with shock-absorbent material in such a manner that the secondary container does not become loose inside the outer container as the ice sublimates.
- In addition to the address label, the outer container must also have the etiologic agents/biomedical material label (red logo against a white background) affixed as well as a notice to the carrier as follows:
NOTICE TO CARRIER
This package contains LESS THAN 50 ml of AN ETIOLOGIC AGENT N.O.S., is packaged and labeled in accordance with the US PHS Interstate Quarantine Regulations (42 CFR, Section 72.25(c), (1) and (4), and MEETS ALL REQUIREMENTS FOR SHIPMENT BY MAIL AND ON PASSENGER AIRCRAFT. This shipment is EXEMPTED FROM ATA RESTRICTED ARTICLES TARIFF 6D (see General Requirements 386([d]) and from DOT HAZARDOUS MATERIALS REGULATIONS (see 49 CFR, Section 173,386[d]). SHIPPER'S CERTIFICATES, SHIPPING PAPERS, AND OTHER DOCUMENTATION OR LABELING ARE NOT REQUIRED.