Step 6.1 – Develop SOPs
SOPs must be developed or adapted for TB infection skin or blood-based tests, for:
- identifying individuals for whom the test should be performed;
- collecting, processing, storing and transporting specimens to the testing laboratory;
- laboratory testing for IGRAs, and tuberculin injection and induration reading for TB infection skin tests;
- data security and confidentiality (see Area 7);
- process controls (internal QC) and external quality assessment (see Area 8);
- recording and reporting of results (see Area 9); and
- waste management.
It is essential to have a well-defined, comprehensive set of SOPs that addresses all aspects of the testing processes – from sample collection to reporting of results – as well as for skin test administration and induration size reading, because errors at any step can have a significant impact on the quality of testing. Some SOPs will rely on the manufacturer’s protocols included with commercial kits whereas others will need to be developed. SOPs must be made readily available for staff and must be updated regularly, both for clinical and laboratory staff.
Step 6.2 – Update clinical procedures and strengthen the clinical–laboratory interface
A comprehensive plan to implement or scale up diagnostic testing for TB infection must address all relevant parts of the diagnostic cascade, not just what happens in the laboratory. In addition to SOPs for TB infection testing, clear clinical protocols and guidance will be needed for selecting patients to be tested, ordering tests, interpreting test results, reporting results and making patient-care decisions. Before the introduction of a new diagnostic test or any changes in an existing test, all clinical staff involved in the diagnosis and management of patients must be informed about the planned changes, and relevant training must be conducted. Information must also be shared with clinical staff at all referral sites through staff training opportunities and through use of standardized educational materials developed by the NTP.
This planning is now well accepted as part of implementation of a new laboratory test, and should be considered equally essential when implementing or scaling up TST or TBST.