scope:

It is clear that the transport of clinical specimens is a critical component for accurate diagnosis. The preservation of inherent, interpretive attributes of microorganisms and/or nucleic acids can be quickly compromised when the transport conditions or transport devices are suboptimal. The advent of antigen detection methods, methods for amplification and detection of genetic elements, and the requirement for local or distant transport of these specimens to a testing facility has imposed further considerations on manufacturers to provide products that will not compromise the ability of the laboratory to provide clinically relevant data to physicians. Clinicians should be able to collect and submit specimens to the laboratory with a reasonable assurance that the transport device will maintain the viability of microorganisms and/or preserve nucleic acids present in the specimen. Laboratorians should be able to retrieve specimens from containers, devices, and transport media with a reasonable assurance that representative components of the specimen were maintained during transport.

This standard provides criteria to the manufacturers and end users of transport devices to assist in provision of dependable products for the transport of microbiological clinical specimens. Manufacturers will be able to state whether or not the performance characteristics of a particular product satisfy the performance standards as specified in this document. Furthermore, manufacturers shall state whether or not any additional testing is required prior to the use of a particular product.

In this document, except as specifically noted, quality control consists of an assessment of the performance characteristics of a complete device and not the individual components. There are multiple variables involved in the manufacture of a transport device, including, but not limited to, the container, transport medium, collection device, packaging, and atmosphere. It is fundamental that the assessment of the device be directed at measurable performance characteristics for the particular device.

This document is not intended to provide proprietary information on product development, but rather to provide to the device user assurance that manufacturer claims are met following standardized testing and acceptance criteria. It provides guidance to the manufacturer in addressing critical issues related to specimen integrity specific to the type of testing to be performed, e.g., bacterial and viral culture, or nucleic acid detection. This document does not address the technique of transport device manufacture, but focuses on the methods for quality control testing and acceptance criteria to provide a product suitable for analysis of clinical specimens for agents of disease.

Transport devices are essential components of the preanalytical process of microbiology laboratory testing. It is recognized that these early steps in the total testing process are critical to production of clinically relevant information. Patients, physicians, healthcare providers, and laboratorians expect products that meet the highest standards of laboratory practice. This document will facilitate this goal.^a And while it is beyond the scope of this document to address the design of devices, it is imperative that device design promotes correct use, and that laboratorians select devices that best serve the user needs of the physician and the patient.

Although a discussion of specimen transport conditions is beyond the scope of this document, it is recognized that temperature has a significant effect on preservation of microorganisms in various transport devices. There are a number of recent studies that have compared performance of transport devices inoculated with various organisms at room temperature (20 ºC to 25 ºC) and cold temperature (4 ºC to 8 ºC). These studies have found simulated transport performance at cold temperatures to be superior to room temperature. These data support the suggestion that the current recommendations of room temperature transport do not represent the optimal holding temperature for maximum preservation of microbiological samples.7-14 If transport conditions of the end user differ from those validated by the manufacturer, actual transport conditions should also be tested in order to determine viability and overgrowth of organisms (i.e., in insulated coolers with cold packs).

We encourage manufacturers to perform quality control of microbial transport devices at both 20 ºC to 25 ºC and 4 ºC to 8 ºC, and furthermore to specify this in their package inserts and regulatory submissions. This will permit users who wish to transport specimens for testing by their laboratories at 4 ºC to 8 ºC assurance that manufacturers performed testing at the temperature used by their laboratories. If further investigations lead to changes in the current recommendations for room temperature specimen transport, manufacturers performing quality control at both temperatures would not have to make any subsequent changes in their quality control procedures or package inserts. Finally, the members of the subcommittee wish to emphasize that few standards for quality control have been suggested for many microbiology transport devices. For this reason, some of the protocols provided are general outlines designed, in part, to promote discussion among the manufacturers, laboratories, and users regarding what would constitute an appropriate standard, as well as promote research and publication that may serve as the foundation of new standards as activity in this area moves forward.

^a For example, in the U.S., the Clinical Laboratory Improvement Amendments (CLIA) guidelines place the responsibility for acceptance of quality specimens on the laboratorian.