11.1 General considerations
The guidelines in this section apply to reports of possible transfusion-transmitted infection (TTI) arising from blood or blood components supplied by the UK Blood Transfusion Services. Any suspected cases of TTI should be documented and fully assessed to determine whether further investigation of donors and/or donation samples is required or warranted. The guidance contained within this section covers the action to be taken at the Blood Centre in such cases.
Because TTI may be asymptomatic, cases may not be recognized or detected until months or years after the transfusion. Many cases come to light through incidental screening or specific testing on development of late clinical features of the infection in question. Cases may therefore be notified by sources other than the hospital blood bank, but close liaison will be required with the hospital blood bank that supplied the blood for transfusion and the reporting clinician.
Reports of possible TTI must be recorded and retained. Wherever possible, details of the notification should be confirmed in writing.
For each report, confirmation of clinical and laboratory details will be required. Ideally, these should take the form of copies of the relevant recipient blood tests and computer printouts of transfusion records. Other forms of reporting of transfusion history (by letter, typed lists, etc) should be avoided in view of the risk of transcription errors.
11.2 Assessment of validity of the possible diagnosis of TTI
Clinical and laboratory details of the case should be reviewed to assess the validity of a diagnosis of possible TTI. Further information or test results may be required and requested at this stage.
Every effort should be made to collect all necessary information before taking any action with respect to contact with or additional investigation of donors. However, once a full assessment has taken place action may be considered to prevent issue of any further donations from involved blood donors. Similarly, a search for in date components from recent donations should be carried out.
When a decision has been made to commence an investigation into the case, consideration should be given as to which donors require further investigation, and whether this can be
satisfactorily carried out with samples already available at the blood centre from the index or any subsequent donation. This decision is dependent on the premise that subsequent samples may conclusively demonstrate the development of infectious markers (e.g. antibodies) in one of the implicated donors. It is expected that blood establishments will retain samples from each donation for a minimum period of three years in a suitable frozen archive. The retrieval of samples from this archive must be fully documented and be restricted mainly to such investigations.
If further investigation is required, and suitable blood samples are not available from the donor, then the decision may be made to contact the donor and request further samples.
Decisions for each case and each donor will be on an individual basis depending upon the circumstances, timing, assessed likelihood of TTI, and resources required. In cases of doubt, there should be a mechanism to ensure that there is a system for review and agreement on the way forward.
It will not always be necessary to carry out further investigations on the donor and/or donations, as testing of subsequent donations may provide sufficient information.