Congenital haptoglobin deficiency discovered on the occasion of anaphylaxis induced by platelet concentrate transfusion.

A 77-year-old man with myelodysplastic syndrome suffered from duodenal perforation after undergoing endoscopic submucosal dissection (ESD) for treatment of duodenal cancer. He presented with hemorrhagic shock, peritonitis and disseminated intravascular coagulation (DIC), and received transfusions of red blood cells (RBC), fresh frozen plasma (FFP), γ-globulin and albumin (Alb). One month after the last RBC transfusion, prolonged thrombocytopenia was observed, and platelet concentrate (PC) was transfused. However, immediately after starting PC transfusion, he developed dyspnea, hypotension and rash, and was thus diagnosed as being in anaphylactic shock. Analysis of the patient's serum revealed absence of haptoglobin (Hp) and the presence of anti-Hp antibody. Further studies, using PCR detected Hpdel, yielded a diagnosis of congenital Hp deficiency. Thus, the anaphylactic shock was considered to have been induced by Hp in the transfused PC reacting with pre-existing anti-Hp antibodies. Thereafter, transfusions were safely carried out with the use of washed PC. Congenital Hp deficiency is relatively prevalent, and in such cases transfusions should be carried out using washed RBC, washed PC and congenital Hp deficiency donor derived FFP to avoid anaphylactic transfusion reactions. Transfusions would be even safer if production of congenital Hp deficiency donor derived PC were to be made available in the future.

Antibody against immunoglobulin E contained in blood components as causative factor for anaphylactic transfusion reactions.

BACKGROUND: Determining the mechanism underlying the development of transfusion reactions is important in transfusion therapy. Two bags of fresh-frozen plasma obtained from a donor (index donor) were implicated in two cases of anaphylactic transfusion reactions. STUDY DESIGN AND METHODS: The serum prepared from the index donor plasma transfused into the second patient (Patient 2) was evaluated using cord blood-derived mast cells (CBMCs) incubated with Patient 2 plasma. The component in the serum required for the degranulation was determined and quantified by chromatography in combination with degranulation assay, Western blot analysis, and enzyme-linked immunosorbent assay. The component in the plasma required for CBMC sensitization was determined using human immunoglobulin (Ig)E or normal plasma in place of Patient 2 plasma in the assay. Sera collected from the index donor between 2001 and 2008 were examined for the CBMC degranulation factor. RESULTS: The donor serum activated CBMCs incubated with Patient 2 plasma. The IgG fraction of the donor serum induced degranulation of CBMCs sensitized with IgE or plasma containing a normal IgE concentration. The IgG anti-IgE at a concentration higher than 2200 ng/mL, which showed CBMC degranulation activity, was detected in the donor sera for at least 7 years. CONCLUSION: Transfusion of a high concentration of the anti-IgE in the donor plasma was suggested to induce mast cell degranulation in the patients leading to the development of anaphylactic transfusion reactions. Antibodies existing in not only the patient circulation but also the transfused blood might cause transfusion-induced anaphylaxis.

Novel swine model of transfusion-related acute lung injury.

BACKGROUND: Transfusion-related acute lung injury (TRALI) is a life-threatening complication of blood transfusion. Antibodies against human leukocyte antigens in donors' plasma are the major causes of TRALI. Several animal models of TRALI have been developed, and the mechanism underlying TRALI development has been extensively investigated using rodent models. Although sheep models of nonimmune TRALI have been developed, large-animal models of antibody-mediated TRALI are not yet available. STUDY DESIGN AND METHODS: To develop a swine model of TRALI, male Clawn strain miniature pigs were used. A monoclonal antibody (MoAb) against swine leukocyte antigens (SLAs) Class I (4G8, 0.3 or 1.0 mg/kg body weight [BW]) and a control antibody (1.0 mg/kg BW) were injected into the peripheral vein after priming with or without 1 µg/kg BW lipopolysaccharide (LPS; n = 3 each). Lung injury was assessed using PaO2 /FiO2 (P/F) ratio and by chest X-ray imaging. Histopathologic analysis was also conducted. RESULTS: Lung injury could be induced by injecting 4G8 at an amount of 1.0 mg/kg BW, after LPS. The P/F ratio 90 minutes after the administration of 4G8 significantly decreased (p < 0.05). Bilateral infiltration was shown in chest X-ray imaging. Lung injury was confirmed by histopathologic analysis. CONCLUSION: Lung injury in pigs was successfully induced by anti-SLA MoAb. Priming with LPS is a prerequisite for inducing lung injury and the amount of the antibody is a critical condition.

Immunoglobulin E oligomers identified in blood components activate mast cells: relevance to anaphylactic transfusion reaction.

BACKGROUND: In most cases of anaphylactic transfusion reaction, the mechanisms underlying its development are unclear. We found a donor whose transfused blood components were implicated in two cases of anaphylactic transfusion reaction, and we found that the donor plasma showed mast cell degranulation activity. STUDY DESIGN AND METHODS: The donor plasma was examined to identify the mast cell-activating factors in it. Cultured mast cells prepared from cord blood were used for in vitro degranulation assay. Serum prepared from the donor plasma was fractionated by three-step chromatography using mast cell degranulation activity as a marker. The fractions selected from the third step of chromatography were analyzed by mass spectrometry after separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The characteristics of the identified proteins and other plasma samples that had been donated by the donor over several years were examined. RESULTS: Two plasma proteins of high molecular weight were detected in the anion-exchange fractions and identified as human immunoglobulin (Ig)Es of 500 kDa and higher. The mast cell degranulation activity of the IgEs decreased in the presence of monomeric human IgE as well as an anti-human IgE antibody. Mast cell degranulation activity was detected in the donor plasma since January 4, 2002, when the first case was reported. CONCLUSION: We identified high-molecular-weight IgEs as the mast cell-activating factors in the donor plasma. Results of analysis suggest that these IgEs were dimeric and trimeric and that they directly activated the transfusion recipient's mast cells by triggering the crosslinking of Fcε receptor I, thereby inducing an anaphylactic transfusion reaction.

Detection of Hpdel among Thais, a deleted allele of the haptoglobin gene that causes congenital haptoglobin deficiency.

BACKGROUND: Congenital haptoglobin deficiency is a risk factor for anaphylactic nonhemolytic transfusion reactions in Japan. The deleted allele of the haptoglobin gene, Hp(del), which causes congenital haptoglobin deficiency, has also been observed in other Northeast Asian populations, such as Korean and Chinese persons. It has not been reported in several African and European-African populations, however, or investigated in other countries. STUDY DESIGN AND METHODS: To investigate the distribution of congenital haptoglobin deficiency in Southeast Asian countries, blood samples collected from 200 randomly selected healthy Thai volunteers were analyzed for serum haptoglobin and the haptoglobin gene. Plasma haptoglobin concentration was measured to identify haptoglobin deficiency. Haptoglobin phenotyping was performed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by Western blotting. The presence of the Hp(del) allele was determined with genomic DNA by an Hp(del)-specific polymerase chain reaction (PCR) method. RESULTS: There were no haptoglobin-deficient subjects detected among the 200 Thais. Their haptoglobin phenotypes were as follows: Hp 1-1 in 10, Hp 2-1 in 81, and Hp 2-2 in 109. Six individuals heterozygous for Hp(del) were detected. The frequency of the Hp(del) allele was calculated to be 0.015. The prevalence of haptoglobin deficiency caused by Hp(del) homozygosity was estimated to be approximately 1 in 4000. CONCLUSION: Congenital haptoglobin deficiency caused by Hp(del) homozygosity is presumed to be present in Thailand as a risk factor for anaphylactic transfusion reactions with a frequency similar to that in Japan. The causative deleted allele of the haptoglobin gene, Hp(del), is distributed among Southeast Asian populations as well as among Northeast Asian populations.

Anaphylactic transfusion reactions in haptoglobin-deficient patients with IgE and IgG haptoglobin antibodies.

BACKGROUND: Patients with haptoglobin deficiency associated with haptoglobin IgG antibodies, who experienced severe nonhemolytic transfusion reactions (NHTRs), have been identified in Japan. Haptoglobin deficiency therefore might be a risk factor for NHTRs. STUDY DESIGN AND METHODS: A total of 4138 cases of voluntarily reported NHTRs in Japan, including 367 cases of immediate-onset anaphylactic NHTRs, were examined to identify haptoglobin deficiency. Serum haptoglobin IgG and IgE antibodies were determined in haptoglobin-deficient patients to elucidate the mechanism underlying the transfusion reactions. RESULTS: Seven patients with haptoglobin deficiency were identified. Six of them experienced severe and acute NHTRs. Six of them were identified to be homozygous for the Hpdel allele of the haptoglobin gene. Both haptoglobin IgG and IgE antibodies were detected in serum samples of all the patients. The stimulative effects of blood transfusion on the production of hap- toglobin antibodies in the patients and the relation- ship between the presence of the antibodies and the occurrence of the transfusion reactions were observed. CONCLUSION: Anaphylactic NHTRs in these patients with haptoglobin deficiency associated with serum haptoglobin antibodies were suggested to be prevalent in Japan. In addition to IgG antibodies, IgE haptoglobin antibodies detected in the sera of such patients were suggested to play a role in the occurrence of the reactions.