Hemostasis and complement in allogeneic hematopoietic stem cell transplantation: clinical significance of two interactive systems.

Hematopoietic stem cell transplantation (HCT) represents a curative treatment option for certain malignant and nonmalignant hematological diseases. Conditioning regimens before HCT, the development of graft-versus-host disease (GVHD) in the allogeneic setting, and delayed immune reconstitution contribute to early and late complications by inducing tissue damage or humoral alterations. Hemostasis and/or the complement system are biological regulatory defense systems involving humoral and cellular reactions and are variably involved in these complications after allogeneic HCT. The hemostasis and complement systems have multiple interactions, which have been described both under physiological and pathological conditions. They share common tissue targets, such as the endothelium, which suggests interactions in the pathogenesis of several serious complications in the early or late phase after HCT. Complications in which both systems interfere with each other and thus contribute to disease pathogenesis include transplant-associated thrombotic microangiopathy (HSCT-TMA), sinusoidal obstruction syndrome/veno-occlusive disease (SOS/VOD), and GVHD. Here, we review the current knowledge on changes in hemostasis and complement after allogeneic HCT and how these changes may define clinical impact.

Proteomic profiling for biomarker discovery in heparin-induced thrombocytopenia.

ABSTRACT: New analytical techniques can assess hundreds of proteins simultaneously with high sensitivity, facilitating the observation of their complex interplay and role in disease mechanisms. We hypothesized that proteomic profiling targeting proteins involved in thrombus formation, inflammation, and the immune response would identify potentially new biomarkers for heparin-induced thrombocytopenia (HIT). Four existing panels of the Olink proximity extension assay covering 356 proteins involved in thrombus formation, inflammation, and immune response were applied to randomly selected patients with suspected HIT (confirmed HIT, n = 32; HIT ruled out, n = 38; and positive heparin/platelet factor 4 [H/PF4] antibodies, n = 28). The relative difference in protein concentration was analyzed using a linear regression model adjusted for sex and age. To confirm the test results, soluble P-selectin was determined using enzyme-linked immunosorbent assay (ELISA) in above mentioned patients and an additional second data set (n = 49). HIT was defined as a positive heparin-induced platelet activation assay (washed platelet assay). Among 98 patients of the primary data set, the median 4Ts score was 5 in patients with HIT, 4 in patients with positive H/PF4 antibodies, and 3 in patients without HIT. The median optical density of a polyspecific H/PF4 ELISA were 3.0, 0.9, and 0.3. Soluble P-selectin remained statistically significant after multiple test adjustments. The area under the receiver operating characteristic curve was 0.81 for Olink and 0.8 for ELISA. Future studies shall assess the diagnostic and prognostic value of soluble P-selectin in the management of HIT.

Accuracy of Diagnosing Heparin-Induced Thrombocytopenia.

Importance: Heparin-induced thrombocytopenia (HIT) is a life-threatening condition that requires urgent diagnostic clarification. However, knowledge of the diagnostic utility of the recommended diagnostic tests is limited in clinical practice. Objective: To evaluate the current diagnostic practice for managing the suspicion of HIT. Design, Setting, and Participants: This prospective diagnostic study was conducted from January 2018 to May 2021 among consecutive patients with suspected HIT from 11 study centers in Switzerland, Germany, and the United States. Detailed clinical data and laboratory information were recorded. Platelet factor 4/heparin antibodies were quantified using an automated chemiluminescent immunoassay (CLIA). A washed-platelet heparin-induced platelet activation (HIPA) test was used as a reference standard to define HIT. Exposures: Suspicion of HIT. Main Outcomes and Measures: The primary outcome was the diagnostic accuracy of the 4Ts score, the CLIA, and the recommended algorithm serially combining both tests. Results: Of 1448 patients included between 2018 and 2021, 1318 were available for the current analysis (median [IQR] age, 67 [57-75] years; 849 [64.6%] male). HIPA was positive in 111 patients (prevalence, 8.4%). The most frequent setting was intensive care unit (487 [37.0%]) or cardiovascular surgery (434 [33.0%]). The 4Ts score was low risk in 625 patients (46.8%). By 2 × 2 table, the numbers of patients with false-negative results were 10 (9.0%; 4Ts score), 5 (4.5%; CLIA), and 15 (13.5%; recommended diagnostic algorithm). The numbers of patients with false-positive results were 592 (49.0%; 4Ts score), 73 (6.0%; CLIA), and 50 (4.1%; recommended diagnostic algorithm), respectively. Conclusions and Relevance: In this diagnostic study of patients suspected of having HIT, when the recommended diagnostic algorithm was used in clinical practice, antibody testing was required in half the patients. A substantial number of patients were, however, still misclassified, which could lead to delayed diagnosis or overtreatment. Development of improved diagnostic algorithms for HIT diagnosis should be pursued.

Impact of Additional Administration of von Willebrand Factor Concentrates to Thrombocyte Transfusion in Perioperative Bleeding in Cardiac Surgery.

Background: Von Willebrand factor (vWF) is an important part of blood coagulation since it binds platelets to each other and to endothelial cells. In traumatic and surgical haemorrhage, both blood cells and plasmatic factors are consumed, leading to consumption coagulopathy and fluid resuscitation. This often results in large amounts of crystalloids and blood products being infused. Additional administration of vWF complex and platelets might mitigate this problem. We hypothesize that administration of vWF concentrate additionally to platelet concentrates reduces blood loss and the amount of blood products (platelets, red blood cells [RBC], fresh frozen plasma [FFP]) administered. Methods: We conducted a monocentric 6-year retrospective data analysis of cardiac surgery patients. Included were all patients receiving platelet concentrates within 48 h postoperatively. Patients who additionally received vWF concentrates were allocated to the intervention group and all others to the control group. Groups were compared in mixed regression models correcting for known confounders, based on nearest neighbour propensity score matching. Primary endpoints were loss of blood (day one and two) and amount of needed blood products on day one and two (platelets, RBC, FFP). Secondary endpoints were intensive care unit (ICU) and in-hospital length of stay, ICU and in-hospital mortality, and absolute difference of platelet counts before and after treatment. Results: Of 497 patients analysed, 168 (34%) received vWF concentrates. 121 patients in both groups were considered for nearest neighbour matching. Patients receiving additional vWF were more likely to receive more blood products (RBC, FFP, platelets) in the first 24 h after surgery and had around 200 mL more blood loss at the same time. Conclusion: In this retrospective analysis, no benefit in additional administration of vWF to platelet concentrates on perioperative blood loss, transfusion requirement (platelets, RBC, FFP), length of stay, and mortality could be found. These findings should be verified in a prospective randomized controlled clinical trial (www.clinicaltrials.gov identifier NCT04555785).

Tranexamic Acid for Intracerebral Hemorrhage in Patients on Non-Vitamin K Antagonist Oral Anticoagulants (TICH-NOAC): A Multicenter, Randomized, Placebo-Controlled, Phase 2 Trial.

BACKGROUND: Evidence-based hemostatic treatment for intracerebral hemorrhage (ICH) associated with non-vitamin K antagonist oral anticoagulants (NOACs) is lacking. Tranexamic acid (TXA) is an antifibrinolytic drug potentially limiting hematoma expansion. We aimed to assess the efficacy and safety of TXA in NOAC-ICH. METHODS: We performed a double-blind, randomized, placebo-controlled trial at 6 Swiss stroke centers. Patients with NOAC-ICH within 12 hours of symptom onset and 48 hours of last NOAC intake were randomized (1:1) to receive either intravenous TXA (1 g over 10 minutes followed by 1 g over 8 hours) or matching placebo in addition to standard medical care via a centralized Web-based procedure with minimization on key prognostic factors. All participants and investigators were masked to treatment allocation. Primary outcome was hematoma expansion, defined as ≥33% relative or ≥6 mL absolute volume increase at 24 hours and analyzed using logistic regression adjusted for baseline hematoma volume on an intention-to-treat basis. RESULTS: Between December 12, 2016, and September 30, 2021, we randomized 63 patients (median age, 82 years [interquartile range, 76-86]; 40% women; median hematoma volume, 11.5 [4.8-27.4] mL) of the 109 intended sample size before premature trial discontinuation due to exhausted funding. The primary outcome did not differ between TXA (n=32) and placebo (n=31) arms (12 [38%] versus 14 [45%]; adjusted odds ratio, 0.63 [95% CI, 0.22-1.82]; P=0.40). There was a signal for interaction with onset-to-treatment time (Pinteraction=0.024), favoring TXA when administered within 6 hours of symptom onset. Between the TXA and placebo arms, the proportion of participants who died (15 [47%] versus 13 [42%]; adjusted odds ratio, 1.07 [0.37-3.04]; P=0.91) or had major thromboembolic complications within 90 days (4 [13%] versus 2 [6%]; odds ratio, 1.86 [0.37-9.50]; P=0.45) did not differ. All thromboembolic events occurred at least 2 weeks after study treatment, exclusively in participants not restarted on oral anticoagulation. CONCLUSIONS: In a smaller-than-intended NOAC-ICH patient sample, we found no evidence that TXA prevents hematoma expansion, but there were no major safety concerns. Larger trials on hemostatic treatments targeting an early treatment window are needed for NOAC-ICH. REGISTRATION: URL: https://clinicaltrials.gov; Unique identifier: NCT02866838.

[Folie à deux - Thrombosis and Infections]. / Folie à deux ­ Thrombose und Infektionen.

Folie à deux - Thrombosis and Infections Abstract: Although infections are not represented in the Revised Geneva or Wells score, they increase the risk of venous thromboembolism (VTE) similarly to the known risk factors (immobilization, major surgery, active neoplasia). This increased risk of VTE can persist for six to twelve months after infection; moreover, the more severe the infection, the higher the risk of VTE may be. In addition to VTEs, infections can promote arterial thromboembolism. For example, 20% of pneumonias are accompanied by an acute cardiovascular event (acute coronary syndrome, heart failure, atrial fibrillation). In the case of infection-associated atrial fibrillation, the CHA2DS2 VASc score remains an appropriate guide for the indication of anticoagulation.

Limited concordance of heparin/platelet factor 4 antibody assays for the diagnosis of heparin-induced thrombocytopenia: an analysis of the TORADI-HIT study.

BACKGROUND: Anecdotal reports suggest that the correlation between heparin/platelet factor 4 (PF4) antibody assays for the diagnosis of heparin-induced thrombocytopenia (HIT) is limited. OBJECTIVES: To investigate the correlation between widely used assays and examine possible factors contributing to variability. METHODS: This is a large, prospective cohort study with 10 participating tertiary care hospitals including 1393 patients with suspected HIT in clinical practice. HIT was defined by a positive heparin-induced platelet activation (HIPA) assay (washed platelet reference standard test). Three different immunoassays were used to measure heparin/PF4 antibodies: chemiluminescent immunoassay, enzyme-linked immunosorbent assay, and particle gel immunoassay. Various factors that could influence the assays were examined: sex (male or female), age (<65 years or ≥65 years), unfractionated heparin exposure, presence of thrombosis, cardiovascular surgery, and intensive care unit. Spearman's correlation coefficients were calculated. Z-scores and diagnostic odds ratios were determined in the aforementioned subgroups of patients. RESULTS: Among 1393 patients, 119 were classified as HIT-positive (prevalence, 8.5%). The median 4Ts score was 5 (IQR, 4-6) in patients with HIT compared with 3 (IQR, 2-4) in patients without HIT. Correlations (rs) between immunoassays were weak (0.53-0.65). Inconsistencies between immunoassays could not be explained by further analyses of z-scored test results and diagnostic odds ratios in subgroups of patients. CONCLUSION: The correlation between widely used heparin/PF4 antibody assays was weak, and key factors could not explain this variability. Standardization of immunoassays is requested to improve comparability.

Enhancement of the haemostatic effect of platelets in the presence of high normal concentrations of von Willebrand factor for critically ill patients needing platelet transfusion-a protocol for the will-plate randomised controlled trial.

INTRODUCTION: von Willebrand Factor (vWF) is a key protein mediating platelet adhesion on the surface of damaged endothelia. To the best of our knowledge, no trial exists that investigated the effect of platelet transfusion in combination with the administration of balanced vWF in severe blood loss, despite being widely used in clinical practice. The Basel Will-Plate study will investigate the impact of the timely administration of balanced vWF (1:1 vWF and FVIII) in addition to platelet transfusion on the need for blood and coagulation factor transfusion in patients admitted to the intensive care unit (ICU) who suffer from severe bleeding. The study hypothesis is based on the assumption that adding balanced vWF to platelets will reduce the overall need for transfusion of blood products compared to the transfusion of platelets alone. METHODS AND ANALYSIS: The Will-Plate study is an investigator-initiated, single-centre, double-blinded randomised controlled clinical trial in 120 critically ill patients needing platelet transfusion. The primary outcome measure will be the number of fresh frozen plasma (FFP) and red blood cell (RBC) transfusions according to groups. Secondary outcome measures include the number of platelet concentrates transfused within the first 48 h after treatment of study medication, quantity of blood loss in the first 48 h after treatment with the study medication, length of stay in ICU and hospital, number of revision surgeries for haemorrhage control, ICU mortality, hospital mortality, 30-day mortality and 1-year mortality. Patients will be followed after 30 days and 1 year for activities of daily living and mortality assessment. The sample size was calculated to detect a 50% reduction in the number of blood products subsequently transfused within 2 days in patients with Wilate® compared to placebo. ETHICS AND DISSEMINATION: This study has been approved by the Ethics Committee of Northwestern and Central Switzerland and will be conducted in compliance with the protocol, the current version of the Declaration of Helsinki, the ICH-GCP or ISO EN 14155 (as far as applicable) and all national legal and regulatory requirements. The study results will be presented at international conferences and published in a peer-reviewed journal. TRIALS REGISTRATION: ClinicalTrials.gov NCT04555785. PROTOCOL VERSION: Clinical Study Protocol Version 2, 01.11.2020. Registered on Sept. 21, 2020.

A machine-learning model for reducing misdiagnosis in heparin-induced thrombocytopenia: A prospective, multicenter, observational study.

Background: Diagnosing heparin-induced thrombocytopenia (HIT) at the bedside remains challenging, exposing a significant number of patients at risk of delayed diagnosis or overtreatment. We hypothesized that machine-learning algorithms could be utilized to develop a more accurate and user-friendly diagnostic tool that integrates diverse clinical and laboratory information and accounts for complex interactions. Methods: We conducted a prospective cohort study including 1393 patients with suspected HIT between 2018 and 2021 from 10 study centers. Detailed clinical information and laboratory data were collected, and various immunoassays were conducted. The washed platelet heparin-induced platelet activation assay (HIPA) served as the reference standard. Findings: HIPA diagnosed HIT in 119 patients (prevalence 8.5%). The feature selection process in the training dataset (75% of patients) yielded the following predictor variables: (1) immunoassay test result, (2) platelet nadir, (3) unfractionated heparin use, (4) CRP, (5) timing of thrombocytopenia, and (6) other causes of thrombocytopenia. The best performing models were a support vector machine in case of the chemiluminescent immunoassay (CLIA) and the ELISA, as well as a gradient boosting machine in particle-gel immunoassay (PaGIA). In the validation dataset (25% of patients), the AUROC of all models was 0.99 (95% CI: 0.97, 1.00). Compared to the currently recommended diagnostic algorithm (4Ts score, immunoassay), the numbers of false-negative patients were reduced from 12 to 6 (-50.0%; ELISA), 9 to 3 (-66.7%, PaGIA) and 14 to 5 (-64.3%; CLIA). The numbers of false-positive individuals were reduced from 87 to 61 (-29.8%; ELISA), 200 to 63 (-68.5%; PaGIA) and increased from 50 to 63 (+29.0%) for the CLIA. Interpretation: Our user-friendly machine-learning algorithm for the diagnosis of HIT (https://toradi-hit.org) was substantially more accurate than the currently recommended diagnostic algorithm. It has the potential to reduce delayed diagnosis and overtreatment in clinical practice. Future studies shall validate this model in wider settings. Funding: Swiss National Science Foundation (SNSF), and International Society on Thrombosis and Haemostasis (ISTH).

Programmable DARPin-based receptors for the detection of thrombotic markers.

Cellular therapies remain constrained by the limited availability of sensors for disease markers. Here we present an integrated target-to-receptor pipeline for constructing a customizable advanced modular bispecific extracellular receptor (AMBER) that combines our generalized extracellular molecule sensor (GEMS) system with a high-throughput platform for generating designed ankyrin repeat proteins (DARPins). For proof of concept, we chose human fibrin degradation products (FDPs) as markers with high clinical relevance and screened a DARPin library for FDP binders. We built AMBERs equipped with 19 different DARPins selected from 160 hits, and found 4 of them to be functional as heterodimers with a known single-chain variable fragments binder. Tandem receptors consisting of combinations of the validated DARPins are also functional. We demonstrate applications of these AMBER receptors in vitro and in vivo by constructing designer cell lines that detect pathological concentrations of FDPs and respond with the production of a reporter and a therapeutic anti-thrombotic protein.

[Harvest of Stem Cells from Umbilical Cord Blood: Relevance of Perinatal Factors for the Quality of Umbilical Cord Transplant Units]. / Gewinnung von Stammzellen aus Nabelschnurblut: Relevanz peripartaler Faktoren für die Qualität von Transplantaten.

INTRODUCTION: Umbilical cord blood (UCB) contains hematopoietic stem cells with therapeutic potential and unique cellular properties. Due to the limited number of stem cells in the UCB (surrogate marker total nucleated cells, TNC), only one in five donations is suitable for transplantation. The aim of this study was to investigate whether predictive factors exist for a TNC count above the 99th percentile. MATERIAL AND METHODS: Retrospective data analysis of the 100 largest donations from 2,299 registered UCB units. Differences between maternal, fetal, and obstetric factors were analyzed and compared with a standardized cohort of 731 registered UCB units. RESULTS: maternal age and BMI in the Top100 cohort were higher compared with the comparative cohort (32 vs. 31 years, p=0.007; 30 kg/m2 vs. 29 kg/m2, p=0.024). There were significantly more P1 (76.0 vs. 62.8%, p=0.013) and women with gestational diabetes (5.00 vs. 1.65%, p=0.044). The gestational week, birth weight, the proportion of vaginal-operative deliveries and secondary caesarean sections were higher in the Top100 cohort (40+4 vs. 40+1 wks, p=0.002), (3700 vs. 3450 g, p<0.001), (53.0 vs. 22.7%, p<0.001) (10 vs. 6.2%, p=0.014). CONCLUSION: For a successful transplant, the amount of TNC in the UCB unit is crucial. Vaginal-operative deliveries, secondary caesarean sections, and a birth weight above 3700 g are favorable with regard to stem cell content. In cases with a complicated course of delivery, collection should not be neglected once the mother and child are safely cared for.

Dual targeting of JAK2 and ERK interferes with the myeloproliferative neoplasm clone and enhances therapeutic efficacy.

Myeloproliferative neoplasms (MPN) show dysregulated JAK2 signaling. JAK2 inhibitors provide clinical benefits, but compensatory activation of MAPK pathway signaling impedes efficacy. We hypothesized that dual targeting of JAK2 and ERK1/2 could enhance clone control and therapeutic efficacy. We employed genetic and pharmacologic targeting of ERK1/2 in Jak2V617F MPN mice, cells and patient clinical isolates. Competitive transplantations of Jak2V617F vs. wild-type bone marrow (BM) showed that ERK1/2 deficiency in hematopoiesis mitigated MPN features and reduced the Jak2V617F clone in blood and hematopoietic progenitor compartments. ERK1/2 ablation combined with JAK2 inhibition suppressed MAPK transcriptional programs, normalized cytoses and promoted clone control suggesting dual JAK2/ERK1/2 targeting as enhanced corrective approach. Combined pharmacologic JAK2/ERK1/2 inhibition with ruxolitinib and ERK inhibitors reduced proliferation of Jak2V617F cells and corrected erythrocytosis and splenomegaly of Jak2V617F MPN mice. Longer-term treatment was able to induce clone reductions. BM fibrosis was significantly decreased in MPLW515L-driven MPN to an extent not seen with JAK2 inhibitor monotherapy. Colony formation from JAK2V617F patients' CD34+ blood and BM was dose-dependently inhibited by combined JAK2/ERK1/2 inhibition in PV, ET, and MF subsets. Overall, we observed that dual targeting of JAK2 and ERK1/2 was able to enhance therapeutic efficacy suggesting a novel treatment approach for MPN.

Identification of Patients with Cobalamin Deficiency Crucially Depends on the Diagnostic Strategy.

BACKGROUND: Our goal was to determine vitamin B12 (cobalamin) deficiency with different diagnostic strategies, to propose the best possible laboratory strategy, and to synthesize the relevance of biomarkers in the diagnosis of a cobalamin deficiency. METHODS: We performed a secondary data analysis. The testing strategies were (i) vitamin B12 solely, (ii) holotranscobolamin solely, (iii) vitamin B12 and holotranscobolamin, and (iv) reflex testing of holotranscobalamin in samples with vitamin B12 < 300 pmol. A set of 3,044 laboratory samples with vitamin B12 and holotranscobalamin serum values from unselected in- and outpatients from a secondary care hospital. A sample was classified as cobalamin deficient when low values of vitamin B12 < 137 pmol/L or holotranscobalamin ≤ 37 pmol/L were measured. RESULTS: Low cobalamin values were identified in 591 (19.4%) samples either according to low vitamin B12 values (305; 10.0%) or low holotranscobalamin values (436; 14.3%). For 2,404 values with vitamin B12 < 300 pmol/L, the additional measurement of holotranscobalamin (reflex-testing) enabled the detection of an additional 278 (9.1%) deficiencies. When the grey zone was decreased to 138 - 219 pmol/L, the reflex testing of an additional 1,240 samples identified a total of 511 (16.8%) samples as cobalamin deficient. CONCLUSIONS: The identification of cobalamin deficiency or sufficiency highly depends on the diagnostic strategy. A reflex testing with a grey zone for vitamin B12 < 220 pmol/L identifies cobalamin deficiency cost efficiently in 86.5% cases (511 out of 591). Physicians should apply a uniform strategy on how to address the diagnosis of cobalamin deficiency and indication for treatment. In-hospital guidelines, which describe methodology and sensitivity of the locally used assays for vitamin B12 and holotranscobalamin could guide them.

Blast counts are lower in the aspirate as compared to trephine biopsy in acute myeloid leukemia and myelodysplastic syndrome expressing CD56.

INTRODUCTION: CD56 is aberrantly expressed in myeloid neoplasms including myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML). Considering the adhesion effects of CD56, blast quantification in bone marrow might depend on the technique used to obtain respective diagnostic specimens. Therefore, the objective of our study was to investigate the impact of CD56-expression on blast counts in myeloid neoplasms comparing bone marrow aspirates to biopsies. METHODS: We retrospectively analyzed 75 patients diagnosed with MDS and AML. We compared patients with (n = 36) and without (n = 39) CD56-expression by flow cytometry with respect to their blast quantities assessed on bone marrow aspirates versus biopsies. RESULTS: The frequency of CD56-expression on blasts correlated with higher blast counts on biopsies vs. aspirate smears (rs  = 0.52; P = .001). This difference in blast counts was only significant in the CD56 high expressing subgroup (median 68%, 5.5%-95% in biopsy compared to median 32.5%, 1.5%-90% in aspirate; P < .01). The percentage of CD56-positive blasts among the total blast population was lower in the peripheral blood compared to bone marrow (median 31%, 6%-88% vs. 55%, 14%-98%; P = .016). The discrepancy in the blast count between the aspirate and trephine biopsy would have led to misclassification of four cases as MDS instead of AML, if diagnosis had based on the bone marrow aspirate blast count alone. CONCLUSION: Counting blasts in bone marrow aspirates of CD56-positive AML and MDS may be linked to underestimation, potentially leading to misclassification of these myeloid neoplasms, and should therefore be adjusted considering the results obtained on trephine biopsies for reliable diagnosis.

Antenatal predictors of stem cell content for successful umbilical cord blood donation.

PURPOSE: The most important HLA-independent factor for the selection of cord blood units (CBU) for hematopoietic stem cell transplantation is the total nucleated cell (TNC) count over 150 × 107 as a surrogate marker for stem cell content. The purpose of this prospective study was to define prenatal clinical predictors for TNC count that would help to identify successful CBU donors before the onset of active labor. METHODS: This was a prospective analysis of 594 CBUs, collected from all eligible term singleton pregnancies at Basel University Hospital between 4/2015 and 9/2016 analyzing several maternal and fetal factors. The impact of these factors on TNC count (< 150 × 107 cells vs. ≥ 150 × 107 cells) of the CBUs was modeled in a multivariate analysis. RESULTS: A total of 114 (19.2%) CBUs had a TNC count of ≥ 150 × 107. In a ROC analysis there was no significant difference between the AUC of all prenatal factors (AUC 0.62) and estimated fetal birth weight by ultrasound alone (AUC 0.62). For women planning a trial of labor a recruitment cut-off at an estimated birth weight of 3300 g would allow 72.6% of all donors with sufficient TNC count to be recruited and 22.8% of all collected CBUs would have a sufficient TNC count for banking. For women planning for elective CS a cut-off of 3400 g would allow 71.4% of all donors with sufficient TNC count to be recruited and 22.7% of all collected CBUs would have sufficient TNC count for banking. CONCLUSION: The estimated fetal birth weight within 2 weeks of delivery by ultrasound as single parameter can be considered at the time of recruitment to estimate the chances of a successful CBU donation.

Acquired haemophilia A in the postpartum and risk of relapse in subsequent pregnancies: A systematic literature review.

BACKGROUND: About 1%-5% of acquired haemophilia A cases affect mothers in the postpartum setting. AIMS: This study delineates the characteristics of this disease, specific to the postpartum setting, notably relapse in subsequent pregnancies. METHODS: Report of two cases and literature study (1946-2019), yielding 73 articles describing 174 cases (total 176 cases). RESULTS: Patients were aged 29.9 years (17-41) and 69% primigravidae. Diagnosis was made at a median of 60 days after delivery (range 0-308). Bleeding types were obstetrical (43.4%), cutaneous (41.3%), and muscular (36.7%). In >90% of the cases, FVIII at diagnosis was <1% (range 0%-8%). FVIII inhibitor was documented in 75.4% cases (median titre of 20 BU/ml, range 1-621). Haemostatic treatment was necessary in 57.1% using fresh frozen plasma (16%), factor concentrate (27.6%) and/or bypassing agents (37.4%). Immunosuppressive treatment was administered in 90.8%, mostly steroids (85.3%), alone or combined with immunosuppressants (27%). Rituximab was used mostly as a second line treatment. Only 24 patients (13.6%) had documented subsequent pregnancies and 6 (22.2%) suffered haemophilia recurrence during pregnancy. CONCLUSION: This study allows better definition of: (1) clinical and laboratory characteristics of postpartum acquired haemophilia, (2) response to therapy, and (3) the risk of relapse for subsequent pregnancies.

Haemophagocytic lymphohistiocytosis and liver failure-induced massive hyperferritinaemia in a male COVID-19 patient.

The authors present the case of a 58-year-old man with the unique combination of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and, later on, haemophagocytic lymphohistiocytosis admitted to the intensive care unit. During his ICU stay the patient developed a variety of complications including acute respiratory distress syndrome, pulmonary embolism, right heart failure and suspected HLH leading to multiorgan failure and death. Despite the proven diagnosis of haemophagocytic lymphohistiocytosis, the excessively high ferritin levels of the patient did not seem fully explained by this diagnosis. Therefore, the authors want to highlight different causes of hyperferritinaemia in critically ill patients and underline the importance of differential diagnoses when interpreting continuously rising ferritin levels.

Cellular immunotherapy with multiple infusions of in vitro-expanded haploidentical natural killer cells after autologous transplantation for patients with plasma cell myeloma.

BACKGROUND AIMS: To investigate the feasibility and safety of haploidentical natural killer (NK) cell infusions as consolidation immunotherapy after autologous stem cell transplant (ASCT) in patients with plasma cell myeloma. METHODS: Ten patients (median age, 59 years) received induction treatment followed by high-dose melphalan (200 mg/m2) at day -1, ASCT at day 0 and increasing NK cell doses (1.5 × 106, 1.5 × 107 and multiple doses of 1.0 × 108 cells/kg body weight) from day +1 to day +30 after ASCT. NK cells were harvested and purified from peripheral blood of haploidentical donors and expanded for 19 days with interleukin (IL)-2 and IL-15 under Good Manufacturing Practice conditions. RESULTS: NK cell numbers increased 56.0-fold (37.4- to 75.5-fold). Patients received a median of 3.8 × 108 (0.9-5.7 × 108) NK cells/kg body weight in six (three to eight) infusions. Multiparametric mass cytometry analysis demonstrated an altered surface receptor repertoire of expanded NK cells with increased degranulation and cytokine production activities but diminished expression of perforin. Donor NK cells were detectable in the peripheral blood, peaking 1 h after each dose (up to 90% donor NK cells). The treatment was safe and well tolerated, without evidence of graft-versus-host disease. Comparison with a control patient population receiving ASCT without NK cell infusions showed no significant difference in relapse, progression-free survival and overall survival. CONCLUSIONS: This study demonstrates reliable manufacturing of high numbers of activated NK cells for multiple-dose infusions and safe administration of these cellular products. The trial was registered at ClinicalTrials.gov (identifier no. NCT01040026).