Severe Anemia two weeks post transfusion

[caj1018]

Patient CB admitted to ICU with hgb 3.5. Type and Screen result - O Neg with negative antibody screen. Patient is given 2 O Neg immediate spin units and post transfusion Hgb is 4.5. Dr orders DAT and result is negative. Pathologist review indicates moderate spherocytes. Bilirubin is 6 and plasma is bright yellow. Pt is a 41 F and had hysterectomy and 2 unit transfusion on 1/15/07. Previous transfusions in 2006 and 2005. No history of allo or autoantibodies. I repeated the DAT using crossmatch sample and obtained microscopic positive with poly and negative with IgG at immediate spin and 1+ positive with poly and still negative with IgG using tube method. i performed a tube panel using poly AHG and received negative results. A post transfusion specimen was sent to ARC reference lab and a negative DAT was resulted. Patient's Hgb dropped to 2.9 and 2 more O neg units were given. Medication history was reviewed and Pharmacy could not find any evidence that Cefotetan was ever used, however, the patient has received Keflex which is also a cephalosporin and has been associated with positive DAT. A small amount of red cells from the crossmatch sample was sent to ARC reference lab for phenotyping. This sample yielded a 4+ DAT using IgG Gel.

The patient's LDH is approx 300 and Haptoglobin is also Elevated. This patient was referred to a Hematologist who suspects an autoimmune IgM process. He orders a cold agglutinin titer and a wonder drug was ordered but takes 24 hours to arrive. The cold agglutinin titer is negative.

This is where we are at and this is a real live case. I have a VERY small amount of pretransfusion cells left to send to ARC on Monday 2/5.

The varying DAT results and elevated Haptoglobin are not consistent with a delayed transfusion reaction - so what am I missing here? Do you have any words of wisdom or suggestions?

[Mabel Adams]

There is such a thing as DAT negative immune hemolytic anemia, isn't there? Occasionally an IgA or something??? Probably Issitt mentions it--maybe even Tech Manual.

[Yanxia]

When saw spherocytes elevated in one’s blood ，we will think it perhaps outvascular hemolysis，and the Haptoglobin will not drop。Because the gel test will be influenced by lot of factor，I rather believe the tube test than it。

[conwaysbb]

Are there any other physical abnormalities:i.e. enlarged spleen, enlarged liver...What nationality/race is patient. Any prior history of anemia? What potentiators were used? Albumin, LISS, PEG or enzymes? Recent Hx of viral infection? Has she recently benn out of the country or has she ever lived in another country?

[Melanie]

Did you ever do an eluate? If so, what were the results? Sometimes the eluate is able to pull off an antibody that you can not detect using tube methods. It would be interesting to see how the eluate reacts in tube and using gel.

Were you able to do a complete pretransfusion phenotype?

[Liz0316]

Your DAT can be negative if all the coated cells are sequestered and destroyed. An eluate will concentrate and may shed some light on the issue.

[AMcCord]

If your patient is having a problem with Keflex (cephalosporin), your DAT could be positive for complement only and your antibody screen negative because your reagent cells (and donor cells) are not coated with the antibiotic. I've seen 2 cases of severe anemia with cefotetan that behaved this way. The eluate was hugely positive with antibiotic coated cells and negative with uncoated cells. Interesting and scary!