The immunocompromised patient and transfusion

Hypothermic storage of leukoreduced red blood cells for greater than 21 days is a safe alternative to irradiation

BACKGROUND

Irradiation of red blood cells (RBCs) inactivates residual donor T lymphocytes to prevent transfusion-associated graft-vs-host disease (TA-GVHD) but can have adverse effects on recipients and inventory management. Reported incidence of TA-GVHD is lower when leukoreduced RBCs and older blood products are transfused; therefore, the impact of leukoreduction and storage was evaluated as an alternative prevention strategy.

STUDY DESIGN AND METHODS

Effectiveness of leukoreduction filters on white blood cell (WBC) proliferation was evaluated by filtering buffy coat (BC) products and isolating residual WBCs. Additionally, leukoreduced RBCs were spiked with 5 × 10⁶ WBCs on Day 21 of hypothermic storage, then stored and processed on Days 7, 14, and 21 to obtain residual WBCs to investigate the impact of hypothermic storage on their viability and proliferative ability. Viability of residual WBCs was assessed by staining with annexin V and an antibody cocktail for flow cytometry analysis. Proliferative ability was assessed by placing carboxyfluorescein diacetate succinimidyl ester-labeled residual WBCs into culture for 6 days with phytohemagglutinin before flow cytometry assessment.

RESULTS

Filtration of BC units depleted WBCs, particularly T lymphocytes, to 0.001% ± 0.003% cells/unit, although proliferative activity remained consistent with prefiltration levels of WBCs. WBCs in stored RBCs remained viable even on Day 21 of storage; however, the proliferative activity decreased to 0.24% ± 0.41%.

CONCLUSIONS

Hypothermic storage of RBCs for 21 days or more is sufficient to inactivate T lymphocytes, which may help prevent TA-GVHD when irradiated RBCs are not available.

Cytomegalovirus and Epstein-Barr Infections: Prevalence and Impact on Patients with Hematological Diseases

Cytomegalovirus (CMV) and Epstein-Barr virus (EBV) infections are widely distributed throughout the world. EBV is linked to various hematological and autoimmune disorders whereas CMV might play important role in the progression of chronic hematological diseases, such as hemoglobinopathies, lymphomas, myelomas, hemophilia, and aplastic and sickle cell anemia. Both viruses produce a viral homolog of human interleukin-10 that can cause general suppression of immune response, increasing susceptibility to other infections. These viruses can remain latent in the host cells and be reactivated when the host immune system is compromised. Studies showing the impact of CMV and EBV infections on hematological disorders are scarce and unclear in the context of coinfection. This review intends to present the biology, prevalence, and impact of CMV and EBV infections in patients with hematological diseases.

Perioperative blood usage and therapeutic plasma exchange in kidney transplantation during a 16-year period in South Korea

BACKGROUND

The frequency of kidney transplantation (KT) is increasing. Blood transfusion plays an important role in the success of KT. Therapeutic plasma exchange (TPE) is also used for desensitisation in ABO-incompatible KT and treatment of antibody-mediated rejection.

MATERIALS AND METHODS

We analysed red blood cell (RBC), platelet, and fresh frozen plasma (FFP) usage and the number of TPE procedures performed during the hospitalisation of KT patients from 2002 to 2017 using the Korean National Health Insurance Service-National Health Information Database.

RESULTS

A total of 18,331 KT patients were included in this study. The number of transfused RBCs continued to increase from 4,806 units in 2002-2005 to 12,390 units in 2014-2017. However, the average number of RBCs transfused per patient decreased from 2.17 to 1.79 units. Estimated platelet usage increased from 4,259 units in 2002-2005 to 11,519 units in 2014-2017, and the proportion of filtered platelets increased from 72.6% to 83.4% during the same period. There was a huge increase in the total number of FFP units used, from 2,255 units in 2002-2005 to 51,531 units in 2014-2017. The number of TPE procedures performed also increased from 296 to 6,479 during the same period. Patients with acute rejection accounted for 8.8% of all KT patients, and more RBC and FFP were used for these patients and a greater number of TPE procedures were performed compared to those who did not experience rejection.

DISCUSSION

Blood usage and TPE have increased steadily with the increasing numbers of KTs. Therefore, continuous efforts are needed to ensure appropriate perioperative blood preparation and usage for KT patients.

Seroprevalence of Cytomegalovirus among Voluntary Blood Donors

BACKGROUND

Primary cytomegalovirus (CMV) infection in immunocompetent host is self limiting infection, leading to latency of virus. However congenital CMV and CMV infections in immunocompromised patients are associated with high morbidity and mortality. Transfusion transmitted-cytomegalovirus (TT-CMV) infection in low birth weight neonate and immunocompromised transfusion recipients is being increasingly reported. Studies recommended transfusion of CMV free or CMV safe blood in prevention of TT-CMV. In this background, the study was undertaken to assess the CMV seroprevalence in blood donor.

METHODS

A prospective study was conducted in which 431 voluntary blood donors were screened for CMV IgG and IgM by EIA (Enzyme Immuno Assay).

RESULT

A total of 379 (87.9 %) voluntary blood donors were seropositive for CMV IgG. There was no statistical difference of CMV seropositivity and age. Further, seven (1.6%) subjects were both CMV IgM and IgG seropositive.

CONCLUSION

High seroprevalence of CMV in our donor population is a threat to the blood safety. Strategies in reducing the risk of TT- CMV are discussed. Use of prestorage leucodepleted 'CMV safe' blood components along with judicious use of blood is recommended in prevention of TT-CMV in high risk recipients.

Deletion 22q11.2 syndrome--implications for the intensive care physician

OBJECTIVE

To report on the experience of a pediatric intensive care unit (PICU) with patients with deletion 22q11.2 syndrome: 1) to delineate the clinical characteristics and management of these patients; 2) to assess whether these patients were managed appropriately, especially in terms of blood transfusion; and 3) to make recommendations for PICU management.

DESIGN

Retrospective assessment of medical records of patients with fluorescent in situ hybridization-proven 22q11 deletion admitted to the PICU at the Children's Hospital at Westmead, Sydney.

SETTING

PICU in a tertiary university-affiliated children's hospital.

PATIENTS

Sixty-five consecutive admissions in 40 patients with diagnosis of 22q11 deletion over a 4-yr period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Thirty-seven (57%) of 65 admissions were postoperative cardiac surgical and accounted for the most common reason for admission to the PICU. Thirteen (20%) admissions were for velopharyngeal/laryngeal problems. Four (6%) admissions were associated with hypocalcemia, with two being first presentations. Five (12.5%) of 40 patients had immune dysfunction, one of whom developed cytomegalovirus pneumonitis. Twenty-nine (72.5%) patients received blood products either immediately before PICU admission or in the PICU. Of these, 16 received nonirradiated cellular blood products. There were two deaths from complications of congenital heart disease.

CONCLUSIONS

PICUs need to be familiar with deletion 22q11.2 syndrome, especially the recommended use of irradiated and cytomegalovirus-seronegative blood components in these immunocompromised patients. The guidelines were inconsistently followed in the cohort of patients reported here. The extent of this problem may be more widespread in PICUs, and we recommend that individual units review their practice in this regard. Hypocalcemia may manifest at any time, and a regular survey of the calcium status is required in the intensive care setting. Admission to PICU should afford the opportunity to invite subspecialty referral and optimize extended care.

Anesthetic management of a child with chromosome 22q11 deletion syndrome

Chromosome 22q11 deletion syndrome (22q11DS) is a congenital anomaly characterized by cardiovascular, oropharyngeal, immunologic, endocrine, and neurodevelopmental abnormalities. We successfully managed a 6-year-old girl with 22q11DS with general anesthesia. Potential problems in anesthetic management of patients with 22q11DS are reviewed.