The impact of an antibody investigation algorithm emphasizing specificity on reducing potential false-positive warm autoantibody detection at a Canadian tertiary care centre.

BACKGROUND AND OBJECTIVES: To reduce potential false-positive warm autoantibody (WAA) by solid-phase red cell adherence assay (SPRCA), our centre implemented a new antibody investigation algorithm (AIA) by classifying cases with panreactive SPRCA but negative saline-indirect antiglobulin test as 'antibody of undetermined significance' (AUS) after excluding clinically significant antibodies. We assessed the effects of the new AIA and subsequent alloantibody formation in patients with AUS. MATERIALS AND METHODS: Samples from patients with positive SPRCA screens between 1 September 2017 and 31 August 2021 were selected for the study. Frequencies of antibodies classified by the old and new AIAs were compared using Fisher's exact test. Patient demographics, transfusion history and antibody formation in cases of AUS were collected. RESULTS: A significant reduction in potential WAA frequencies from 127/1167 (11%) to 53/854 (6%) was observed (p < 0.001) when compared between the old and new AIAs among 2021 positive SPRCA antibody screens. While no patients with AUS later transitioned to potential WAA using the new AIA, four patients developed alloantibodies, including anti-E, anti-C, both anti-C and anti-E, and anti-Wra . CONCLUSION: A significant reduction in the frequencies of potential false-positive WAA detection at our centre was observed after implementing the new AIA, leading to less resource and phenotypically matched red blood cell (RBC) use. Some patients still developed subsequent RBC alloimmunization, so clinically relevant alloantibodies should be carefully excluded before determining AUS, taking forming or evanescent antibodies into consideration.

The estimated negative impacts on the red blood cell inventory of reducing shelf-life at two large health authorities in British Columbia, Canada, using a discrete-event simulation model.

BACKGROUND AND OBJECTIVES: Reducing the maximum red blood cell (RBC) shelf-life is under consideration due to potential negative effects of older blood. An assessment of the impacts of this change on blood supply chain management is evaluated. MATERIALS AND METHODS: We performed a simulation study using data from 2017 to 2018 to estimate the outdate rate (ODR), STAT order and non-group-specific RBC transfusion at two Canadian health authorities (HAs). RESULTS: Shortening shelf-life from 42 to 35 and 28 days led to the following: ODRs (in percentage) in both HAs increased from 0.52% (95% confidence interval [CI] 0.50-0.54) to 1.32% (95% CI 1.26-1.38) and 5.47% (95% CI 5.34-5.60), respectively (p < 0.05). The estimated yearly median of outdated RBCs increased from 220 (interquartile range [IQR] 199-242) to 549 (IQR 530-576) and 2422 (IQR 2308-2470), respectively (p < 0.05). The median number of outdated redistributed units increased from 152 (IQR 136-168) to 356 (IQR 331-369) and 1644 (IQR 1591-1741), respectively (p < 0.05). The majority of outdated RBC units were from redistributed units rather than units ordered from the blood supplier. The estimated weekly mean STAT orders increased from 11.4 (95% CI 11.2-11.5) to 14.1 (95% CI 13.1-14.3) and 20.9 (95% CI 20.6-21.1), respectively (p < 0.001). The non-group-specific RBC transfusion rate increased from 4.7% (95% CI 4.6-4.8) to 8.1% (95% CI 7.9-8.3) and 15.6% (95% CI 15.3-16.4), respectively (p < 0.001). Changes in ordering schedules, decreased inventory levels and fresher blood received simulated minimally mitigated these impacts. CONCLUSION: Decreasing RBC shelf-life negatively impacted RBC inventory management, including increasing RBC outdating and STAT orders, which supply modifications minimally mitigate.

Concurrent Primary Follicular Lymphoma and a Mature Cystic Teratoma of the Ovary: A Case Report and Review of Literature.

Primary lymphoma concurrent with teratoma of the ovary is exceedingly rare. Based on our review of the literature, there are only 8 case reports describing concurrent primary diffuse large B-cell lymphoma and teratoma. Here, we report the first case of primary follicular lymphoma concurrent with mature ovarian cystic teratoma, which, to our knowledge, has not been described in the literature.

Significant Transplantation-Related Mortality from Respiratory Virus Infections within the First One Hundred Days in Children after Hematopoietic Stem Cell Transplantation.

Respiratory viral infections (RVI) are important in hematopoietic stem cell transplantations (HSCT) and knowledge regarding incidence, morbidity, mortality, and long-term pulmonary complications is limited. We report a study to evaluate incidence and outcomes, both short and long-term, of RVI in children receiving HSCT. Between January 2000 and December 2012, 844 patients underwent hematopoietic stem cell transplantation (HSCT) at the Hospital for Sick Children: 491 were allogeneic and 353 were autologous. When screening for causes of death in the first year after HSCT in the 844 patients, we found that RVI as a cause of death was only evident in the first 100 days after HSCT. Fifty-four (6.5%) patients were found to have an RVI within the first 100 days after HSCT (allogeneic = 32, autologous = 22). Upper and lower respiratory tract infections were documented in 31 (57%) and 23 (43%) patients, respectively. Viruses were parainfluenza (35%), respiratory syncytial virus (28%), influenza (22%), adenovirus (7%), human metapneumovirus (4%), coronavirus (2%), and rhinovirus (2%). Three patients relapsed with their primary disease before day 100 and were excluded. The overall mortality for the remaining 51 patients was 10% (allogeneic = 4, autologous = 1). All 5 deaths were directly attributable to RVI and all 5 deaths occurred in patients with a lower respiratory tract infection. The remaining patients were followed for a median of 4.3 years (range, 1.4 to 11.8) and no chronic pulmonary complications were observed. A clear seasonal pattern for contracting RVI was evident with 65% of total RVI occurring between October and March (35 of 427 versus 19 of 417, P = .03). Given the significant mortality from RVI and the challenges in preventing them, choosing the time to start HSCT, whenever possible, may help prevent RVI and improve outcomes.

Intramuscular anti-D in chronic immune thrombocytopenia children with severe thrombocytopenia.

Nine patients with chronic immune thrombocytopenia and platelet counts <20 × 10(9) /L, with a median age of 7.8 (3.8-15.5) years, received three phases of 10 mcg/kg/dose of intramuscular anti-D. Phase 1 was anti-D daily for 5 days, followed by phase 2, anti-D weekly for 12 weeks and withheld when platelet counts ≥ 20 × 10(9) /L, and then phase 3 was anti-D once every 2 weeks for 24 weeks. According to the International Working Group criteria, in phase 1, 66.7% of patients responded to the treatment. In phases 2 and 3, 11.1% (0-41.7%) and 7.7% (0-33.3%) of total episodes of follow up, respectively, responded to the treatment. Therefore, intramuscular anti-D given at a dose of 10 mcg/kg for 5 days is an alternative method to raise platelet counts in chronic immune thrombocytopenia children with severe thrombocytopenia where the intravenous form of anti-D is not available.

Allogeneic hematopoietic stem cell transplantation for children with severe aplastic anemia.

OBJECTIVE: Allogeneic hematopoietic stem cell transplantation (allo-SCT) is a potentially curative treatment for severe aplastic anemia (SAA). This is a single institutional review to study the feasibility of using allo-SCT for Thai children with SAA. MATERIAL AND METHOD: Nine children with SAA (7 matched-sibling donor-SCT, 1 matched-unrelated donor-SCT and 1 haploidentical-SCT) underwent allo-SCT between October 2002 and September 2010. Cyclophosphamide and anti-thymocyte globulin (CY/ATG) were used as conditioning regimen for 4 patients with matched-sibling donor-SCT CY/ATG and fludarabine were used for 3 patients with matched-sibling donor-SCT and one patient with haplo-identical SCT. One matched-unrelated donor-SCT received CY/ATG and total body irradiation. RESULTS: Eight of 9 patients (89%) achieved neutrophil engraftment within 13.5 days (range 6.0-22.0). One matched-sibling donor-SCT recipient who failed to achieve engraftment died from acute renal failure and gram-negative sepsis on day 21 post allo-SCT. One matched-sibling donor-SCT case developed late graft failure on day 72 and died from invasive fungal infection. For graft versus host disease (GVHD), a haplo-identical-SCT patient died from steroid refractory grade IV acute GVHD. At last follow-up, six patients (67%) alive at a median follow-up time of 76.4 months (range 2.3-88.8). Overall survival (OS) and event-free survival (EFS) at 5 year was 63% and 65%, respectively. CONCLUSION: Allo-SCT is a feasible curative treatment for children with SAA in Thailand. Graft failure and severe GVHD in alternative donors SCT are responsible for major causes of death. OS and EFS probabilities are stable after the first year post transplant.

Heavy proteinuria following dengue hemorrhagic fever.

We report a case of nephrotic range proteinuria with 24-hour urine protein level of 335.7 mg/kg/day which developed following dengue hemorrhagic fever. Due to prolonged hypoalbuminemia from renal loss, right pleural effusion persisted and required pleuracentesis. The patient did not have classical nephrotic syndrome. The proteinuria improved without specific treatment. A renal biopsy was not performed due to self-resolution of the proteinuria and azotemia. Heavy proteinuria is not a typical characteristic of dengue virus infection, therefore the pathophysiology of this nephropathy has not been well described to date.

Spontaneous subgaleal hemorrhage in a girl with impaired adrenaline-induced platelet aggregation.

INTRODUCTION: Subgaleal hematomas usually develop followed a birth trauma in neonates. This entity is extremely rare in older children and may be associated with coagulation disorders or subaponeurotic vascular malformations. CASE REPORT: The authors report a spontaneous subgaleal hematoma in a 9-year-old girl without scalp injury. Only platelet aggregation test was identified as an impaired responsiveness of platelets to adrenaline with normal coagulogram. This patient underwent both computerized tomography and complete magnetic resonance imaging including angiography and venography of the head. Of these, extensive bilateral frontotemperoparietal subgaleal hematoma was observed without vascular malformation. CONCLUSION: Spontaneous subgaleal hematoma can be associated with platelet function defect.

Hemostatic defects in Thai adolescents with menorrhagia.

Twenty-eight adolescents with menorrhagia by pictorial blood loss assessment chart (PBAC) criteria were investigated for underlying hemostatic defect. CBC, ABO blood group, bleeding time, APTT, PT, TT FVIII:C, VWF:Ag, RiCoF and platelet aggregation study were evaluated. Six patients (21.4%) were addressed with underlying hemostatic defect. Of these, severe aplastic anemia (n=1) and thrombotic thrombocytopenicpurpura (n=1) were identified in 2 patients with low platelets after an initial CBC. Four patients with prolonged bleeding time demonstrated inherited hemostatic defect: von Willebranddisease (VWD) type 3 (n=1), Glanzmann thrombasthenia (n=1) and Bernard-Soulier syndrome (n=2). Median PBAC score of patients with hemostatic defect was significantly higher than that of patients with unknown cause of menorrhagia (436.5 vs. 251.3, p = 0.01). After the exclusion of six patients with well-identified bleeding risks, isolated abnormal platelet aggregation response to adrenaline was detected in 11 (50%) adolescents using platelet aggregation study. No significant difference of median PBAC score was noted among patients with and without evidence of this impaired responsiveness to adrenaline. In addition, the authors also found an abnormal platelet aggregation with adrenaline stimulant in 15 (75%) among 20 healthy female controls who had no history of bleeding diathesis. No significant difference infrequency of abnormal platelet aggregation to adrenaline was observed between affected cases and controls. In summary, an impaired responsiveness of platelets to adrenaline in the present study is insufficient to support its risk of bleeding. On the contrary, the simple test such as CBC and bleeding time revealed a worthy contribution to investigate coexisting coagulopathy in adolescents with menorrhagia.