When you think you should transfuse…don't!

A 48-year-old female presented to the emergency department with severe fatigue. Admission laboratory test results were hemoglobin 6.6 g/dL, platelet count 287,000/μL, and white blood cell count 25,200/μL. Lactate dehydrogenase was elevated at 898 U/L, haptoglobin was markedly decreased (< 31 mg/dL), indirect bilirubin was elevated (5.3 mg/dL), and the absolute reticulocyte count was low at 0.0050/μL. A sample was sent to the immunohematology reference laboratory. The direct antiglobulin test immunoglobulin G was negative; C3 was 1+. All cells were reactive at immediate spin phase, indirect antiglobulin testing (IAT) with polyethylene glycol, with low ionic strength saline, neat, prewarm, and in the solid phase. All cells were nonreactive at IAT-ficin. Additional testing included a cold antibody titer that was 1:4096 and thermal amplitude studies demonstrating reactivity of 2+ at 37°C. These results were consistent with a clinically significant anti-Pr and cold agglutinin disease (CAD). Although rituximab is effective in autoimmune hemolytic anemia, this may take weeks. The patient was treated with pegcetacoplan, a pegylated peptide that targets C3 inhibiting hemolysis. The patient was discharged on day 29 with a hemoglobin of 8 g/dL. This is a report of one of the first patients successfully treated with pegcetacoplan for CAD.

Comparison of RhD Typing Results by Serology and Molecular Methods

OBJECTIVE

Molecular testing determines D antigen status when abnormal serologic results are observed. Molecular testing is routinely batched, resulting in longer turnaround time for abnormal D status resolution. During the interim, obstetric patients with questionable/uninterpretable and weak D typing results by serology, per the immunohematology reference laboratory (IRL) policy, will receive RhD negative blood. This study aimed to determine whether serology results achieved a concordance.

METHODS

Six hospitals provided samples to the IRL (first IRL) for RhD status by DNA. De-identified samples were sent for serology RhD (second IRL). A concordance of ≥80% was acceptable.

RESULTS

Forty-nine samples were evaluated. Results were concordant (65.3% [32/49]) and discordant (34.7% [17/49]). This is significantly lower than clinically acceptable 80% (z = 2.57, P < .05). The turnaround-time was 3.0 hours for serology and 4.4 days for molecular evaluation.

CONCLUSION

Due to a low concordance, serology could not be used in place of molecular testing.