Wendy McSporranTransfusion Practitioner

SaBRE position statement published March 2012The Marsden implemented the recommendations June 2012Dr Mike Potter Marsden Haematologist and chaired the CMV steering group Why did SaBTO advocate leukodepletion? Recap of the steering group report:-

Two methods of reducing the risk compared for effectiveness- CMV seronegative blood components and provision of leucodepleted blood components

Neither is 100% effective

Estimated risk with both is 1.5 3.0% per recipient in the setting of bone marrow transplant (Vamvakas2005)

In recent donor infection CMV DNA was repeatedly present in the plasma of 44% of newly seropositive donorsThe steering group reported the study by Ziemann(2010) which followed up infections of CMV in the donor population17,982 donors 148 new CMV seroconversions13 donors with ongoing primary infectionCMV DNA was detectable in white cells and plasma of the 13 individuals for up to 269 days

Can be infected between donations

Infectious virus may be present as there is a 6 8 week antibody window period for primary infection, so not detectable in testing.

With CMV in the plasma then potentially can still get TT CMV from a leukodepleted CMV Negative donor

Leucodepletion particularly effective at removing monocytes

Studies have shown the amount of white cell depletion required to render the blood component CMV safe

The steering group highlighted that the monitoring of leukodepleted is robust and well monitored by NHSBT.

The screening for IgG and IgM has a sensitivity of > 99.5%

This equates to a failure rate of 1:200

So bottom line nothing is perfect!

So what else was then considered?

In

201

In 2012 it was estimated it would save hospitals 2.5 millionNHSBT adhoc deliveries of CMV Neg platelets -£95,000

Data considered

Getting enough male platelet donors to facilitate TRALI preventionAvoid the cost of HLA antibody screening of female platelet donorsReduction in clinical error, previous SHOT reports 2000 -2010 83 of CMV not provided when it was considered appropriateNone of these cases was reported as a CMV transmissionSo how many SHOT reports of TT CMV?

So if studies comparing methods for risk reduction show 1.5 3% risk in each recipient is lack of reports a genuine reflection?How good is the monitoring? Patients have regular PCR testing but is it audited and transfusion suspected?If the transfusion department gets a phone call to say there is a Neg donor/ Neg recipient with positive PCR how do you follow it up?Are we not getting any phone calls because there really is no TT CMV or because positive PCR is not a major concern treatable and no longer has associated mortality?

Ziemann & Hennig (2014)Studies looking at incidence of transmission in HSCT the numbers of units received per patient huge follow up for confirming TTI!!23 CMV neg/neg patients received 1,847 components, median 55 units per patient but the range 3 to 313.

Are CMV Neg screened components still being requested?

Platelets - London2012/2013 25,6892013/2014 18,136Red Cells - London2012/2013 47,7282013/2014 32,923

Don t know what % are elective transfusion in pregnancy, neonatal & IUT s