mcharapata

We have made a fresh new batch of 0.2M DTT with recent purchased chemical and have tested its performance by treating screening cells and testing for denature of cellano. The reactivity decreased from 3+ to w+, but did not completely denature the antigen. Thoughts?

I'm interested to know how you handle the following: 1) Do you defer donors for positive antibody screens that have demonstrable antibody after the identification is performed? If so, for how long? 2) If you have a postive screen on a donor that previously had an antibody ID performed, do you perform the identification again (each time)? 3) If "yes" to #2, do you have any if/then policies (i.e. only repanel if the ID was last performed greater than 12 months)? 4) If "no" to #2, do you save or discard the red cells? 5) If you save the red cells, how do you label your red cells (i.e. do you label with "previously identified as ...." tag)? Thanks much! I look forward to your reply. Mike

The Verax PGD test was originally cleared only for apheresis and later RDP. We perform the test at issue and typically once the device is loaded, have results within 30 minutes. We use a "mock" humidity chamber (wet papertowels with a plastic cover) because we found during our validation that testing took too long without it. We did have 2 months with a high percentage of false positives in December 2009 & January 2010, but when we switched out lots of the device, the number of reactives went down to the rate we observed prior to November (monthly range of 0.18% to 0.70%). We perform the test on pools (after they have been created) and if positive, test each individual platelet to narrow down which unit is causing the positive result. Positive pools are discarded and a sample of the pool is sent for BacT/Alert. We do not use the device to test apheresis platelets, but rely solely on the BacT/Alert result. The manufacturer indicates the device should be read within a short time frame after the validity marks change color. We have had some occasions were tests were negative at this point, but when checked 10-15 mins later (against manufacturer instructions/recommendations) appeared positive. Verax was able to explain the reason for this to me, but I don't recall the reason at the moment. Our SOPs are setup with instructions to read and discard immediately to prevent potential mis-interpretation of the result.

We are currently using Pall's single random donor platelet filter (Purecell PL) to provide leukoreduced platelet product to pediatric patients. We monitor the effecitveness by measuring 4 selected units each month checking for leukoreduction, platelet recovery, and platelet yield. Since December 2009, we started to see some failures with leukoreduction. We have performed a number of studies associated with investigation resulting in approximately 60 units tested within the past month, and are still experiencing about a 7% failure rate (our acceptance criteria is no greater than 5% failure rate). We have also been sending used filters to Pall for investigation (on failures), but their response time is slow (approximately 1 month). There does not appear to be anything lot specific, process specific, or technique dependent. Because we are having difficulty getting our process under control, we are exploring other ways to provide leukoreduced products to pediatric patients. Here is a list of things we are considering: 1) Discontinue the acceptance of leukoreduced single random platelet orders, but allow orders for leukoreduced 2-unit pools (filtering using Pall's Purecell LRF) Advantages: Leukoreduced pooling process is in control. Therefore product is effectively leukoreduced. Disadvantage: Increased donor exposure to the patient. 2) Discontinue use of Purecell PL filter and begin using Purecell LRF filter to leukoreduce single RDP's. Advantages: The product is effectively leukoreduced (according to previous studies) Disadvantage: The platelet yield and recovery is significantly lower. Additional orders may be necessary to effectively treat the patient. 3) Setup aliquot system for single donor leukoreduced apheresis platelets. Advantages: The product is effectively leukoreduced (according to previous studies) Disadvantage: Apheresis platelet inventory is highly variable. No validated system to provide this product. Apheresis storage bags have storage specifications that when a certain amount has been removed, the remaining product can no longer be stored (according to manufacturer specificaitons) resulting in increased wasted product. Developing, validating and implementation of a process is a long-term project. We are considering (in the short-term) going with either option 1 or option 2. Ultimately, we are moving toward option 3, but this will be long-term. The reason for my post is that I am interested in what other facilties do to provide leukoreduced platelets to pediatric patients. Any other comments regarding our situation is also welcome. Thanks much! Mike

Thanks Laurie!

We've recently received word that Immucor's ElukitII is on backorder until March 17, 2009. We are runnign low ... does anyone have alternate vendor that may supply? Thanks! Mike

We've done some work comparing Biotest antisera vs. Ortho and Immucor reagents. Most of them are comparable. Their anti-e seemed to react better than Ortho, but the same as Immucor (same clones). What is attractive about it is that it is only 5 min incubation (like Ortho) as opposed to 15 minute (like Immucor). Anti-S was attractive from the perspective that their monoclonal anti-S is 5 min incubate, spin and read (no AHG). All pricing information I got from BioTest is consistent or a little better than Ortho/Immucor. It is our plan to switch all Rh reagents to BioTest, Anti-S, and perhaps also Kell's and Kidd's if I can work with them to get the pricing right. The techs did not like their Anti-M and Anti-N as it is 30 min RT incubation, then read (no centrifugation).

A follow-up question in regards to validation of 2x wash for an IgA deficient patient is "what would you establish as the acceptance criteria for residual IgA levels after wash?" Is anyone aware of a publication that could point me in the right direction (or have any thoughts on what to establish as criteria)?

Does anyone read their KB's without oil? If so, what type of validation did you perform? Thanks, Mike

Hello, We are in the midst of coping with a backorder of Fenwal's Glycerolyte 57 Solution. Our inventory has now since been depleted and the backorder will not clear until April. Does anyone know of an equivalent product/vendor to carry us through the backorder? Thanks, Mike