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Prior studies have suggested that immune thrombotic thrombocytopenic purpura (iTTP) may display seasonal variation; however, methodologic limitations and sample sizes have diminished the ability to perform a rigorous assessment. This 5-year retrospective study assessed the epidemiology of iTTP and determined whether it displays a seasonal pattern. Patients with both initial and relapsed iTTP (defined as a disintegrin and metalloprotease with thrombospondin type motifs 13 activity <10%) from 24 tertiary centers in Australia, Canada, France, Greece, Italy, Spain, and the US were included. Seasons were defined as: Northern Hemisphere-winter (December-February); spring (March-May); summer (June-August); autumn (September-November) and Southern Hemisphere-winter (June-August); spring (September-November); summer (December-February); autumn (March-May). Additional outcomes included the mean temperature in months with and without an iTTP episode at each site. A total of 583 patients experienced 719 iTTP episodes. The observed proportion of iTTP episodes during the winter was significantly greater than expected if equally distributed across seasons (28.5%, 205/719, 25.3%-31.9%; p = .03). Distance from the equator and mean temperature deviation both positively correlated with the proportion of iTTP episodes during winter. Acute iTTP episodes were associated with the winter season and colder temperatures, with a second peak during summer. Occurrence during winter was most pronounced at sites further from the equator and/or with greater annual temperature deviations. Understanding the etiologies underlying seasonal patterns of disease may assist in discovery and development of future preventative therapies and inform models for resource utilization.

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Sublethal damage to red blood cells (RBCs) during extracorporeal life support (ECLS) may lead to RBC loss. Using flow cytometry, phosphatidylserine-positive (PhS+) RBCs and RBC extracellular vesicles were quantified as measures of sublethal RBC injury in 41 pediatric ECLS runs, stored RBC units, and normal adult subjects. We estimated the clearance half-life of PhS+ RBCs and compared the rates of RBC loss during pediatric ECLS due to phlebotomy, intravascular hemolysis, and extravascular clearance of PhS+ RBCs. Extracorporeal life support patients had 0.9% PhS+ RBCs, sixfold higher than normal subjects (p < 0.0001). Phosphatidylserine-positive RBCs were increased in stored RBC units (twofold in whole blood derived units, p = 0.0013; 12-fold in apheresis RBC units, p < 0.0001). Phosphatidylserine-positive RBCs were cleared with an average half-life of 15 hours. During ECLS, PhS+ RBC clearance accounted for 7% of RBC loss (1-60%), phlebotomy 12%, and intravascular hemolysis 12%. Increasing PhS+ RBCs occurred in 40% of patients that died on ECLS. Red blood cell extracellular vesicles, another marker of red cell injury/activation, were elevated fivefold during ECLS. Phosphatidylserine exposure on RBCs is increased during ECLS, marking these cells for extravascular clearance with a half-life of ~15 hours and accounting for ~7% of RBC loss.

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BACKGROUND-AIM: Pregnancy induces physiological changes that can affect serologic and immunologic markers, potentially resulting in lower or undetectable haptoglobin values compared to non-pregnant counterparts. Such variations may lead to inaccurate diagnosis of hemolysis. METHODS: We report a case of a patient in second trimester of pregnancy receiving induction chemotherapy due to B-cell acute lymphocytic leukemia with undetectable haptoglobin levels in a routine laboratory sample collected less than 12 h posttransfusion of red cell unit. Despite undetectable haptoglobin, lactate dehydrogenase (LD) was within reference intervals (RI). The patient was evaluated for acute hemolytic transfusion reaction (AHTR) and followed up. Haptoglobin levels showed an upward trend during follow-up visits, reaching 15 mg/dL, and within RI in the third trimester. RESULTS: The patient did not meet the Center for Disease Control (CDC) criteria for AHTR. Alternative explanations for the observed laboratory findings were explored. Undetectable haptoglobin levels were attributed to various factors, including recent RBC transfusion, pregnancy-related physiological changes, and potential hyperhydration treatment plan due to chemotherapy. CONCLUSION: This case underscores the importance of cautious interpretation of laboratory results in pregnant patients, necessitating trimester-specific reference intervals for haptoglobin. A multidisciplinary approach to patient care is crucial for accurate diagnosis and management.

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The thrombotic risk with haemoglobin C trait (HbAC) or haemoglobin C disease (HbCC) is unclear. However, individuals with HbCC have demonstrated chronic haemolysis, higher blood viscosity and altered rheology when compared to individuals with wild-type haemoglobin (HbAA). These physiological alterations may theoretically translate to increased risk of thrombosis; therefore, a systematic literature review was performed to investigate the possible association between HbAC and/or HbCC and thrombosis. Twenty-two studies met inclusion criteria representing 782 individuals with HbAC (n = 694) or HbCC (n = 88). Fifteen studies described the presence/absence of venous thromboembolism (VTE) in patients with HbAC (n = 685) or HbCC (n = 79), while seven studies described patients with HbAC (n = 9) or HbCC (n = 9) and arterial thrombosis. Most (n = 20) studies were case reports or case series; however, two studies suggested a potential increased VTE risk with HbAC compared to HbAA in (i) all patients (OR 2.2, 95% CI: 0.9-5.5) and in (ii) pregnant individuals (RR 3.7, 95% CI 0.9-16). This review is the largest assessment of patients with HbC trait or disease and thrombosis to date; despite its limitations, the findings suggest HbC may be a predisposing risk factor to thrombosis. Prospective cohort studies are warranted to definitively elucidate the risk of thrombosis in this population.

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The Heidenhain variant of Creutzfeld-Jakob disease (CJD) is a rare form that initially presents with visual disturbances. In early stages, the presentation can mimic neuromyelitis optica spectrum disorders (NMOSD) and lead to unnecessary treatment modalities. Herein, we describe a case of a 66-year-old man who presented with bilateral vision loss and retro-orbital discomfort. In addition to immunosuppressive therapy, he received 4 rounds of therapeutic plasma exchange after his preliminary diagnosis of NMOSD. We were surprised to note that his condition did not show improvement but deteriorated, with severe neurocognitive symptoms. Eventually, CJD was suspected, and real-time quaking-induced conversion (RT-QuIC) was performed. By the time the diagnosis of Heidenhain variant of CJD was confirmed, the patient was discharged to hospice care and died shortly after.

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Anti-glomerular basement membrane (anti-GBM) disease (formerly known as Goodpasture's syndrome) is a rare autoinflammatory condition that affects the renal and/or pulmonary capillaries. The standard therapeutic regimen for anti-GBM disease involves therapeutic plasma exchange (TPE), cyclophosphamide, and corticosteroids to rapidly remove and inhibit autoantibody production and reduce organ inflammation. Herein we report an 82-year-old female who developed anti-GBM disease but expired despite therapy, secondary to multi-organ failure in the setting of disseminated adenovirus disease. We discuss the utility and potential adverse effect of daily TPE for a protracted course (ie, 10-14 days), the recommended TPE intensity in the 2023 American Society for Apheresis guidelines, updated from every-other-day TPE in the 2019 guidelines, despite no new data. We also highlight the potential for unusual infections to occur in these patients due to the profound immunosuppression, and discuss the importance of balancing immunosuppression to treat the disease with close surveillance of any potential opportunistic infections.

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Paroxysmal cold hemoglobinuria (PCH) is a rare autoimmune hemolytic anemia often overlooked as a potential etiology of hemolysis and is challenging to diagnose because of the complicated testing methods required. We performed a systematic review of all reported cases to better assess the clinical, immunohematologic, and therapeutic characteristics of PCH. We systematically analyzed PubMed, Medline, and EMBASE to identify all cases of PCH confirmed by Donath-Landsteiner (DL) testing. Three authors independently screened articles for inclusion, and systematically extracted epidemiologic, clinical, laboratory, treatment, and outcomes data. Discrepancies were adjudicated by a fourth author. We identified 230 cases, with median presentation hemoglobin of 6.5 g/dL and nadir of 5.5 g/dL. The most common direct antiglobulin test (DAT) result was the presence of complement and absence of immunoglobulin G (IgG) bound to red blood cells, although other findings were observed in one-third of cases. DL antibody class and specificity were reported for 71 patients, of which 83.1% were IgG anti-P. The use of corticosteroids is common, although we found no significant difference in the length of hospitalization for patients with and without steroid therapy. Recent reports have highlighted the use of complement inhibitors. Among patients with follow-up, 99% (213 of 216) were alive at the time of reporting. To our knowledge, this represents the largest compilation of PCH cases to date. We discovered that contemporary PCH most commonly occurs in children with a preceding viral infection, corticosteroid use is frequent (but potentially ineffective), and DAT results are more disparate than traditionally reported.

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BACKGROUND: Red blood cell (RBC) alloimmunization can occur secondary to transfusion or pregnancy. It is observed most frequently among patients with hemoglobinopathies and myeloid neoplasms. Although previous antigen exposure is generally required for alloimmunization, some alloantibodies may develop naturally without prior exposure. Other alloantibodies may become evanescent, only to reemerge at a detectable titer following a stimulatory event. In a minute fraction of cases, 'non-naturally occurring' alloantibodies may appear without a known antigenic stimulus. METHODS AND MATERIALS: All testing (antibody detection tests and identification, antigen phenotyping, and crossmatching) was performed using the same method and reagents, but occurred at two hospitals within the Yale New Haven Hospital delivery network, and was performed by technologists utilizing different instruments and reagent lots. RESULTS: We present two cases of seemingly de novo alloimmunization (anti-E and anti-K), and one case of re-emergence of a known, previously evanescent alloantibody (anti-K) following transfusion of RBCs that were antigen-negative for the corresponding antibodies. CONCLUSION: While the exact mechanism underlying the development and/or re-emergence of RBC alloantibodies in the absence of antigenic stimulation remains unclear, these cases highlight this unusual phenomenon, underscoring the general immunogenicity, as well as the potential consequences, of RBC transfusion and reiterates the importance of concluding an alloantibody specificity, even in the absence of known transfusion of RBCs with a particular antigen.

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BACKGROUND: Urine drug testing (UDT) monitors prescription compliance and/or drug abuse. However, interpretation of UDT results obtained by liquid chromatography-tandem mass spectrometry (LC-MS-MS) can be complicated by the presence of drug impurities that are detected by highly sensitive methods. Hydrocodone is a drug impurity that can be found as high as 1% in oxycodone pills. OBJECTIVES: We evaluated the frequency and concentration of hydrocodone and its metabolite, hydromorphone, in patients taking oxycodone to check if the ratio of hydrocodone or hydromorphone to oxycodone could distinguish between oxycodone only use from those consuming additional opiates. DESIGN & METHODS: We correlated LC-MS/MS results with medication records of 319 patients with positive oxycodone results over 7 months (4/2021-11/2021). RESULTS: Fifteen of 319 patients with positive oxycodone results were taking oxycodone only. For these 15 patients, the mean ratio of hydrocodone to oxycodone was 0.57% (range 0.05%-3.35%), and the mean ratio of hydromorphone to oxycodone was 0.81% (range 0.18-3.51%). CONCLUSIONS: Hydrocodone and/or hydromorphone are detectable in patients taking only oxycodone and can likely be identified as an impurity if their calculated ratio to oxycodone is <1 %. Further validation of the ratios in a larger sample size is recommended.

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Thrombosis in extracorporeal membrane oxygenation (ECMO) circuits remains a frequent complication. We characterize the location, extent, structure, and clinical implications of thrombi in 53 ECMO circuits from 46 pediatric patients. The tubing, pump, and oxygenator were examined for visible thrombi. Representative samples of thrombi were collected for histologic, immunofluorescence, and immunohistochemical analysis. Thrombi were found in 81% of ECMO circuits. The most clinically significant were inflow oxygenator membrane surface thrombi (11% of circuits), arterial tubing thrombi (30%), and venous tubing (26%) or connector thrombi (26%). Oxygenator membrane surface thrombi resulted in rapidly increasing delta pressure across the oxygenator over 1-2 days, oxygenator failure, and circuit replacement. Oxygenator membrane surface thrombi were associated with intravascular venous thrombosis and bacterial infection before starting ECMO. Arterial cannula/tubing thrombi led in one case to aortic and mesenteric artery thrombosis followed by bowel infarction. In 11% of cases, venous tubing thrombi grew large enough to break off and embolize to the pump, resulting in increased hemolysis. Antifibrinolytic therapy during ECMO was associated with an increased risk of pump thromboembolism. Other less clinically significant thrombi included pump axle thrombi with thrombus fragments trapped in the oxygenator (45%), and deep oxygenator membrane thrombi (15%). Examination of ECMO circuits after removal is a useful quality improvement tool that can elucidate the cause of circuit problems, indicate patients at increased risk of thrombosis, and suggest areas for possible improvements.

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Mantente REAL is a school-based universal program to prevent drug use and other problematic behaviors specifically designed to be implemented in schools at the beginning of adolescence. This program, which is a culturally adapted version of the Keepin’ it REAL intervention, focuses on skills training for resisting social pressure to use drugs and improving psychosocial development. This study aims to evaluate the effectiveness of Mantente REAL on alcohol use in the Spanish context. The sample was composed of 755 adolescents from 12 state secondary schools in Spain, aged 11 to 15 (M = 12.24, SD = 0.56), 47.1% females. The 12 schools were randomly assigned to control and experimental groups, six to each condition. Pre-test and post-test questionnaires data were collected to evaluate the effectiveness of the program. The results indicated that a culturally adapted version of Mantente REAL was effective in preventing alcohol use among youth from northern and southern Spain. Students participating in the program demonstrated changes in the desired direction on alcohol frequency and intoxication episodes. Implications of these results regarding intervention programs aimed at preventing substance use in adolescence are discussed. (AU)

“Mantente REAL” es un programa universal que utiliza la escuela para prevenir el consumo de drogas y otras conductas problemáticas diseñado específicamente para ser implementado en las escuelas al comienzo de la adolescencia. Este programa, que es una versión culturalmente adaptada de la intervención Keepin’ it REAL, se centra en el entrenamiento de habilidades para resistir la presión social para consumir drogas y mejorar el desarrollo psicosocial. Este estudio tiene como objetivo evaluar la eficacia de “Mantente REAL” en el consumo de alcohol en el contexto español. La muestra estuvo compuesta por 755 adolescentes de 12 escuelas secundarias públicas en España, de 11 a 15 años (M = 12.24, DT = 0.56), el 47.1% mujeres. Las 12 escuelas fueron asignadas aleatoriamente a grupo control y experimental, seis en cada condición. Los datos se recopilaron a través de cuestionarios antes y después de la intervención para evaluar la eficacia del programa. Los resultados indicaron que la versión culturalmente adaptada de “Mantente REAL” fue eficaz para prevenir el consumo de alcohol entre los jóvenes del norte y sur de España. Los estudiantes que participaron en el programa demostraron cambios en la dirección deseada en la frecuencia del alcohol y los episodios de intoxicación. Se discuten las implicaciones de estos resultados con respecto a los programas de intervención destinados a prevenir el consumo de sustancias en la adolescencia. (AU)

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OBJECTIVES: Anticoagulation with unfractionated heparin remains the most common therapy used to prevent circuit thrombosis during extracorporeal membrane oxygenation, but no consensus exists on the optimal method or targets for heparin monitoring. From 2015 to 2018, we switched from monitoring heparin during extracorporeal membrane oxygenation using activated clotting times to anti-Xa heparin activity assays. This study describes the transition from activated clotting time to anti-Xa heparin activity assay monitoring and the associated clinical changes. DESIGN: Retrospective analysis at single institution. SETTING: Referral Children's Hospital. PATIENTS: A total of 145 pediatric patients over 152 extracorporeal membrane oxygenation runs using 206 extracorporeal membrane oxygenation circuits. INTERVENTIONS: Anticoagulation protocol quality improvement. MEASUREMENTS AND MAIN RESULTS: From 2015 to 2018, heparin monitoring during extracorporeal membrane oxygenation changed from hourly activated clotting time to anti-Xa heparin activity assay every 6 hours with an associated 75% reduction in the circuit changes per extracorporeal membrane oxygenation day. Over the 4 years, patients with an average anti-Xa heparin activity assay of at least 0.25 U/mL showed a 59% reduction in circuit changes per extracorporeal membrane oxygenation day compared with less than 0.15 U/mL. In addition to its association with reduced circuit changes, anti-Xa heparin activity assay monitoring was also associated with reduced heparin dose changes per day from 11 ± 4 to 2 ± 1 (p < 0.001), smaller heparin dose changes (less variation in dose), and reduced diagnostic phlebotomy volumes from 41 ± 6 to 25 ± 11 mL/day (p < 0.001). The number of patients with reported bleeding decreased from 69% using activated clotting time to 51% (p = 0.03). Transfusion rates did not change. CONCLUSIONS: Over 4 years, we replaced the activated clotting time assay with the anti-Xa heparin activity assay for heparin monitoring during extracorporeal membrane oxygenation. Minimum anti-Xa heparin activity assay levels of 0.25 U/mL were associated with reduced circuit changes. Further studies are needed to determine the optimum anti-Xa heparin activity assay therapeutic range during extracorporeal membrane oxygenation.

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Introducción: La hipotermia terapéutica (HT) es el estándar de cuidado para la encefalopatía hipóxico-isquémica (EHI). El servicio de neonatología implemento el programa de HT en el marco de la red perinatal de la Ciudad de Buenos Aires (RPCABA). Objetivos: Describir la implementación del programa de hipotermia en RPCABA. Reportar la mortalidad, complicaciones y efectos adversos asociados al tratamiento. Métodos: La implementación del programa se realizó en etapas: 1) 2009- 2010 Capacitación y entrenamiento en el uso del equipamiento. 2) 2010 hasta la actualidad: Tratamiento y seguimiento para los pacientes con EHI moderada o grave. Resultados: Hasta Marzo de 2017, 65 neonatos recibieron HT (7 con hipotermia corporal total y los 58 restantes hipotermia activa selectiva), 49 paciente fueron clasificados según la Escala Sarnat & Sarnat como EHI moderada y 16 como EHI grave. Conclusiones: Fue factible implementar el programa en nuestra unidad, auditarlo para mejorarlo y sostenerlo en el tiempo. El sistema de traslado pudo responder ante la activación del "código de hipotermia", cumpliendo tiempos, sosteniendo el tratamiento y el monitoreo adecuado. Creemos necesario mejorar la identificación de neonatos con diagnóstico de EHI en RPCABA. Se necesita nueva capacitación para evitar el subdiagnóstico de esta patología en los centros de nivel 2

Therapeutic hypothermia (TH) is nowadays the gold standard of care for the treatment of hypoxic- ischemic encephalopathy (HIE) in developed countries. The term encephalopathy refers to a diffuse disturbance of brain function, resulting in behavioral changes, altered consciousness or seizures. The brain is particularly vulnerable to even brief interruptions of blood flow or oxygen supply. If the brain´s oxygen supply is insufficient, consciousness is lost rapidly. If oxygenation is restored immediately, consciousness returns without sequelae. However, if oxygen deprivation lasts longer than 1 or 2 minutes, signs of an encephalopathy may persists for hours or permanently. Total ischemic anoxia lasting longer than about 4 minutes usually results in severe irreversible brain damage. The aim of the present report was to describe the implementation of the hypothermia program in a model for the perinatal system at the City of Buenos Aires, with the equipment Cool Cap® for selective hypothermia, and the equipment CFM Olympic 6000® and CFM OMB from Medix® by Natus®, these two to monitoreate the cerebral function. The results obtained are referred, with special consideration to mortality, complications and adverse effects associated with the treatment.

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Therapeutic hypothermia is the standard of care for hypoxic-ischemic encephalopathy (HIE). This treatment was implemented at a regional level by the perinatal network of the City of Buenos Aires. The following are the objectives of this article: 1. To describe the implementation of the network's hypothermia treatment program; 2. To report treatment-associated complications, adverse events and mortality. The program was implemented in stages: 1) 2009-2010. Training and instruction on how to use the equipment. 2) 20102014. Treatment and follow-up of patients with moderate or severe HIE. Up to October 2014, 27 newborn infants received hypothermia treatment with moderate (n= 15) and severe (n= 12) HIE. None of the patients died during treatment. Three newborn infants were lost to follow-up. Among the 16 survivors older than one year old, three have severe neurological disability. Program implementation was plausible. It is imperative to train health care providers on how to identify patients with HIE.

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Cell-free protein synthesis protocols for uniformly deuterated proteins typically yield low, non-uniform deuteration levels. This paper introduces an E. coli cell-extract, D-S30, which enables efficient production of proteins with high deuteration levels for all non-labile hydrogen atom positions. Potential applications of the new protocol may include production of proteins with selective isotope-labeling of selected amino acid residues on a perdeuterated background for studies of enzyme active sites or for ligand screening in drug discovery projects, as well as the synthesis of perdeuterated polypeptides for NMR spectroscopy with large supra-molecular structures. As an illustration, it is demonstrated that the 800-kDa chaperonine GroEL synthesized with the D-S30 cell-free system had a uniform deuteration level of about 95% and assembled into its biologically active oligomeric form.

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The ink cap Coprinopsis cinerea is a model organism for studying fruiting body (mushroom) formation in homobasidiomycetes. Mutant screens and expression studies have implicated a number of genes in this developmental process. Functional analysis of these genes, however, is hampered by the lack of reliable reverse genetics tools for C. cinerea. Here, we report the applicability of gene targeting by RNA silencing for this organism. Efficient silencing of both an introduced GFP expression cassette and the endogenous cgl1 and cgl2 isogenes was achieved by expression of homologous hairpin RNAs. In latter case, silencing was the result of a hairpin construct containing solely cgl2 sequences, demonstrating the possibility of simultaneous silencing of whole gene families by a single construct. Expression of the hairpin RNAs reduced the mRNA levels of the target genes by at least 90%, as determined by quantitative real-time PCR. The reduced mRNA levels were accompanied by cytosine methylation of transcribed and nontranscribed DNA at both silencing and target loci in the case of constitutive high-level expression of the hairpin RNA but not in the case of transient expression. These results suggest the presence of both posttranscriptional and transcriptional gene silencing mechanisms in C. cinerea and demonstrate the applicability of targeted gene silencing as a powerful reverse genetics approach in this organism.

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