Heterogeneity in Approaches for Switching From Universal to Patient ABO Type-Specific Blood Components During Massive Hemorrhage.

CONTEXT.­: ABO mistransfusions are rare and potentially fatal events. Protocols are required by regulatory agencies to minimize this risk to patients, but how these are applied in the context of massive transfusion protocols (MTPs) is not specifically defined. OBJECTIVE.­: To evaluate the approaches used by transfusion services for switching from universally compatible to patient ABO type-specific blood components during massive hemorrhage. DESIGN.­: We added 1 supplemental multiple-choice question to address the study objective to the 2019 College of American Pathologists proficiency test J-survey (J-A 2019). We also reviewed the available literature regarding this topic. RESULTS.­: A total of 881 laboratories responded to the supplemental question. Approximately 80% (704 of 881) reported a policy for ABO-type switching during an MTP. Policies varied considerably between responding laboratories, but most (384 of 704, 55%) required 2 ABO types to match before switching from universal to recipient-specific blood components. Additional safety measures used in a minority of these protocols included reaction strength criteria (103 of 704, 15%), on-call medical director approval (41 0f 704, 5.8%), universal red cell unit number limits (12 of 704, 1.7%), or the presence of a mixed field (3 of 704, 0.4%). CONCLUSIONS.­: This survey reveals that significant heterogeneity exists regarding the available approaches for ABO-type switching during an MTP. Specific expert guidance regarding this issue is very limited, and best practices have not yet been established or rigorously investigated.

Pemphigus, pregnancy, and plasmapheresis.

Pemphigus vulgaris (PV) is an autoimmune blistering disorder that usually occurs in the fifth and sixth decades of life but may occur at younger ages and during pregnancy. Circulating intercellular antibodies directed at desmosomal proteins may cross the placenta and place children at risk for neonatal pemphigus (NP). We describe the case of a pregnant woman with PV treated successfully with a combination of systemic corticosteroids and plasmapheresis. The possibility of PV should be considered in any pregnant woman with a worsening, widespread, mucocutaneous, blistering disease. Plasmapheresis offers a useful alternative to immunosuppressive therapy in the setting of pregnancy.

Automated flow cytometric analysis of blood cells in cerebrospinal fluid: analytic performance.

We compared the performance of an automated method for obtaining RBC and WBC counts and WBC differential counts in cerebrospinal fluid (CSF) samples with the reference manual method. Results from 325 samples from 10 worldwide clinical sites were used to demonstrate the accuracy, precision, and linearity of the method. Accuracy statistics for absolute cell counts showed a high correlation between methods, with correlation coefficients for all reportable absolute counts greater than 0.9. Linearity results demonstrated that the method provides accurate results throughout the reportable ranges, including clinical decision points for WBCs of 0 to 10/microL. Interassay precision and intra-assay precision for the ADVIA 120 (Bayer HealthCare, Tarrytown, NY) method were acceptable at all levels. The ADVIA 120 CSF Assay enumerates and differentiates cells via flow cytometry in a minimally diluted sample, improving the analysis of typically hypocellular CSF samples. Study results demonstrate that the automated ADVIA 120 CSF Assay is an acceptable alternative to the labor-intensive manual method.

Vector-borne illnesses and the safety of the blood supply.

The protection of patients from diseases carried in blood transfusions is an ongoing effort. The viruses that cause long-term human infection and death have received much of the attention in the United States and testing has significantly diminished the risk of infection from a transfusion. As the risk of these diseases has decreased, other transfusion-transmitted organisms with a lower incidence in the community or newer diseases with rapidly expanding endemic areas are receiving additional attention. One group of these infections are infections in which the normal route of human infection is a vector.