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1.
Br J Haematol ; 195(1): 76-84, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34159588

RESUMEN

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a novel entity that emerged in March 2021 following reports of unusual thrombosis after ChAdOx1 nCoV-19, (AstraZeneca) vaccination. Following the recognition of this syndrome, multiple consensus guidelines have been released to risk stratify patients presenting with possible symptoms after ChAdOx1 nCoV-19 vaccination. All guidelines rapidly identify VITT in patients with the complete triad of thrombocytopenia, thrombosis and elevated D-dimers after ChAdOx1 nCoV-19 vaccination. However, with earlier recognition of the associated symptoms, the clinical manifestations are likely to be more heterogeneous and represent an evolving spectrum of disease. In this setting, current guidelines may lack the sensitivity to detect early cases of VITT and risk missed or delayed diagnoses. The broad clinical phenotype and challenges associated with diagnosis of VITT are highlighted in our present case series of four patients with confirmed VITT. Dependent on the guidance used, each patient could have been classified as a low probability of VITT at presentation. The present study highlights the issues associated with the recognition of VITT, the limitations of current guidance and the need for heightened clinical vigilance as our understanding of the pathophysiology of this novel condition evolves.


Asunto(s)
Púrpura Trombocitopénica Idiopática/inducido químicamente , Vacunas/efectos adversos , Adulto , COVID-19 , Femenino , Humanos , Persona de Mediana Edad , SARS-CoV-2
2.
Proc Natl Acad Sci U S A ; 115(30): 7777-7782, 2018 07 24.
Artículo en Inglés | MEDLINE | ID: mdl-29987015

RESUMEN

Biallelic variants in the ERCC excision repair 6 like 2 gene (ERCC6L2) are known to cause bone marrow failure (BMF) due to defects in DNA repair and mitochondrial function. Here, we report on eight cases of BMF from five families harboring biallelic variants in ERCC6L2, two of whom present with myelodysplasia. We confirm that ERCC6L2 patients' lymphoblastoid cell lines (LCLs) are hypersensitive to DNA-damaging agents that specifically activate the transcription coupled nucleotide excision repair (TCNER) pathway. Interestingly, patients' LCLs are also hypersensitive to transcription inhibitors that interfere with RNA polymerase II (RNA Pol II) and display an abnormal delay in transcription recovery. Using affinity-based mass spectrometry we found that ERCC6L2 interacts with DNA-dependent protein kinase (DNA-PK), a regulatory component of the RNA Pol II transcription complex. Chromatin immunoprecipitation PCR studies revealed ERCC6L2 occupancy on gene bodies along with RNA Pol II and DNA-PK. Patients' LCLs fail to terminate transcript elongation accurately upon DNA damage and display a significant increase in nuclear DNA-RNA hybrids (R loops). Collectively, we conclude that ERCC6L2 is involved in regulating RNA Pol II-mediated transcription via its interaction with DNA-PK to resolve R loops and minimize transcription-associated genome instability. The inherited BMF syndrome caused by biallelic variants in ERCC6L2 can be considered as a primary transcription deficiency rather than a DNA repair defect.


Asunto(s)
Alelos , Enfermedades de la Médula Ósea/metabolismo , ADN Helicasas/metabolismo , Reparación del ADN , Enfermedades Genéticas Congénitas/metabolismo , Inestabilidad Genómica , Transcripción Genética , Células A549 , Enfermedades de la Médula Ósea/genética , Enfermedades de la Médula Ósea/patología , ADN Helicasas/genética , Proteína Quinasa Activada por ADN/genética , Proteína Quinasa Activada por ADN/metabolismo , Femenino , Enfermedades Genéticas Congénitas/genética , Enfermedades Genéticas Congénitas/patología , Células HeLa , Humanos , Masculino , ARN Polimerasa II/genética , ARN Polimerasa II/metabolismo , Síndrome
3.
J Antimicrob Chemother ; 73(4): 995-1003, 2018 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-29272419

RESUMEN

Objectives: To develop a pharmacokinetic model describing total and unbound teicoplanin concentrations in patients with haematological malignancy and to perform Monte Carlo simulations to evaluate target attainment of unbound trough concentrations with various dose regimens. Methods: This was a hospital-based clinical trial (EudraCT 2013-004535-72). The dosing regimen was 600/800 mg q12h for three doses then 600/800 mg daily. Serial total and unbound teicoplanin concentrations were collected. Maximum protein binding was estimated from serum albumin concentration. Population pharmacokinetic analyses and Monte Carlo simulations were conducted using Pmetrics®. Target total and unbound trough concentrations were ≥20 and ≥1.5 mg/L, respectively. Results: Thirty adult patients were recruited with a mean (SD) bodyweight of 69.1 (15.8) kg, a mean (SD) CLCR of 72 (41) mL/min and a median (IQR) serum albumin concentration of 29 (4) g/L. A three-compartment complex binding pharmacokinetic model best described the concentration-time data. Total and unbound teicoplanin concentrations were related by serum albumin concentration and a dissociation constant. CLCR and bodyweight were supported as covariates for CL and volume of the central compartment, respectively. Dosing simulations showed that high CLCR was associated with reduced probability of achieving target total and unbound trough concentrations. Low serum albumin concentration was associated with a reduced probability of attaining target total but not unbound trough concentrations. A method to estimate the unbound teicoplanin concentration from the measured total concentration at different serum albumin concentration was demonstrated. Conclusions: Standard teicoplanin dosing regimens should be used with caution in patients with haematological malignancy. Bodyweight, CLCR and serum albumin concentration are important considerations for appropriate dosing.


Asunto(s)
Antibacterianos/administración & dosificación , Antibacterianos/farmacocinética , Neoplasias Hematológicas , Teicoplanina/administración & dosificación , Teicoplanina/farmacocinética , Anciano , Anciano de 80 o más Años , Simulación por Computador , Creatinina/sangre , Femenino , Humanos , Masculino , Tasa de Depuración Metabólica , Persona de Mediana Edad , Método de Montecarlo , Plasma/química , Estudios Prospectivos , Albúmina Sérica/análisis
4.
J Paediatr Child Health ; 54(9): 1011-1015, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29790211

RESUMEN

AIM: Ward rounds are complex activities in which education must be balanced against service. Limited evidence exists regarding how to optimise ward round education. In order to improve the educational experience, we aimed to understand the teaching and learning interactions on ward rounds with a particular focus on the experience of paediatric trainees. METHODS: We conducted an initial quantitative survey as a needs assessment regarding learning and teaching in clinical settings using a structured survey of 21 trainees. This was followed by an observational study using focused ethnography of 20 consultant ward rounds in a general medical department of tertiary paediatric hospital. We used a structured observation form to document ward round characteristics and educational interactions. Data were analysed using inductive content analysis to understand key influences on teaching and learning interactions. RESULTS: Trainees reported a discrepancy between the actual educational value of ward rounds (mean rating 2.7/5) and what they desired (mean 4.3/5). Ward round ethnography revealed examples of excellent education and practice alongside missed opportunities. Explicit education on rounds was dominated by technical content with little focus on other aspects of professionalism. Major influences on educational interactions were the ward round model - consultant-as-expert versus learner-centred - and the hidden curriculum. CONCLUSION: There are many examples of excellence in ward round education, yet there remains substantial scope to better harness the education potential of rounds. This requires us to challenge assumptions, enable feedback and reflection and make learning explicit - while putting the learner at the centre of educational opportunities.


Asunto(s)
Aprendizaje , Pediatría/educación , Derivación y Consulta , Rondas de Enseñanza , Antropología Cultural , Curriculum , Humanos , Encuestas y Cuestionarios
5.
Artículo en Inglés | MEDLINE | ID: mdl-28320714

RESUMEN

The objective of this study was to explore the following aspects of teicoplanin use in patients with hematological malignancy: early attainment of target trough concentrations with current high-dose teicoplanin regimens, variability in unbound teicoplanin fractions, factors associated with observed total and unbound trough concentrations, efficacy and toxicity, and renal function estimation. This was a single-center, prospective study. Samples for determination of trough concentrations were taken on days 3, 4, 7, and 10. Total and unbound teicoplanin concentrations were determined using validated high-performance liquid chromatography methods. Regression analyses were used to identify the factors associated with the trough concentration. Thirty teicoplanin-treated adults with hematological malignancy were recruited. Despite the use of dosages higher than the conventional dosages, the proportions of patients with a trough concentration of ≥20 mg/liter at 48 h and at 72 h were 16.7% and 37.9%, respectively. Renal function was significantly negatively associated with total trough concentrations at 48 h and 72 h (P < 0.05). For an average hematological malignancy patient (creatinine clearance = 70 ml/min), sequential loading doses of at least 12 mg/kg of body weight may be needed to achieve early adequate exposure. In the absence of measured creatinine clearance, estimates obtained using the Cockcroft-Gault (total body weight) equation could prove to be an acceptable surrogate. The unbound fractions of teicoplanin were highly variable (3.4 to 18.8%). Higher unbound fractions were observed in patients with low serum albumin concentrations. Teicoplanin was well tolerated. Teicoplanin loading doses higher than those in current use appear to be necessary. Increased dosing is needed in patients with increased renal function. The high variability in protein binding supports the contention for therapeutic drug monitoring of unbound teicoplanin concentrations. (This study has been registered with EudraCT under registration no. 2013-004535-72.).


Asunto(s)
Antibacterianos/uso terapéutico , Neoplasias Hematológicas/tratamiento farmacológico , Teicoplanina/uso terapéutico , Anciano , Antibacterianos/efectos adversos , Femenino , Neoplasias Hematológicas/sangre , Humanos , Pruebas de Función Renal , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Unión Proteica , Albúmina Sérica/metabolismo , Teicoplanina/efectos adversos
12.
Br J Haematol ; 163(1): 118-22, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23909468

RESUMEN

This retrospective analysis assessed the response, safety and duration of response to standard dose rituximab 375 mg/m(2) weekly for four weeks as therapy for patients with primary or secondary warm autoimmune haemolytic anaemia (WAIHA), who had failed initial treatment. Thirty-four patients received rituximab for WAIHA in seven centres in the Republic of Ireland. The overall response rate was 70·6% (24/34) with 26·5% (9/34) achieving a complete response (CR). The time to response was 1 month post-initiation of rituximab in 87·5% (21/24) and 3 months in 12·5% (3/24) of patients. The median duration of follow-up was 36 months (range 6-90 months). Of the patients who responded, 50% (12/24) relapsed during follow up with a median time to next treatment of 16·5 months (range 6-60 months). Three patients were re-treated with rituximab 375 mg/m2 weekly for four weeks at relapse and responded. There was a single episode of neutropenic sepsis. Rituximab is an effective and safe treatment for WAIHA but a significant number of patients will relapse in the first two years post treatment. Re-treatment was effective in a small number of patients, suggesting that intermittent pulse treatment or maintenance treatment may improve long-term response.


Asunto(s)
Anemia Hemolítica Autoinmune/tratamiento farmacológico , Anticuerpos Monoclonales de Origen Murino/uso terapéutico , Factores Inmunológicos/uso terapéutico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Anemia Hemolítica Autoinmune/complicaciones , Anticuerpos Monoclonales de Origen Murino/efectos adversos , Femenino , Humanos , Factores Inmunológicos/efectos adversos , Irlanda , Masculino , Persona de Mediana Edad , Recurrencia , Estudios Retrospectivos , Rituximab , Resultado del Tratamiento , Adulto Joven
15.
Clin Lymphoma Myeloma Leuk ; 21(10): 694-700, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34148849

RESUMEN

Posttransplant lymphoproliferative disorder (PTLD) is a rare complication of solid organ transplant. We identified 40 patients diagnosed with PTLD between 2009 and 2020 and analyzed their presentation, treatment strategies, and outcomes. Median age at diagnosis was 52.5 years (range 21.3 to 79). Median duration of immunosuppression was 95 months (range 4 to 292). Diffuse large B cell lymphoma (n = 16, 40%) and Burkitt lymphoma (n = 6, 15%) were the most common histological subtypes. First-line therapy varied. The median number of treatment lines was 1 (range 0 to 4). Sixteen patients (40%) achieved complete response after first-line therapy. Nineteen patients (47.5%) relapsed or progressed and received salvage therapy; 45% were alive at the end of the study period (median survival 52 months; range 1 to 266; 95% confidence interval 0 to 104). Causes of death included lymphoma-related (45.5%), therapy-related (27.3%), and other (27.3%). Five (22.7%) died within 3 months of diagnosis. Pearson's r test identified disease stage (P = .045) and proliferation index (P = .005) as negative predictors of response to frontline therapy. Bone marrow involvement (P = .033) and increased age (P = .018) were significant predictors of survival. Early mortality and poor response to frontline therapy are common, outlining the need for improved treatment strategies.


Asunto(s)
Trastornos Linfoproliferativos/diagnóstico , Trasplante de Órganos/métodos , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Periodo Posoperatorio , Factores de Riesgo , Adulto Joven
16.
Clin Hematol Int ; 3(1): 27-33, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34595464

RESUMEN

When the bortezomib [PS341], adriamycin and dexamethasone (PAD) regimen was first evaluated, the response rate in untreated patients was much superior to that elicited by conventional chemotherapeutic agents. We demonstrated the efficacy of PAD in relapsed or refractory patients by comparing the response rate obtained in 53 patients who received vincristine, adriamycin and dexamethasone (VAD) or equivalent regimen as induction therapy, using a comparative design in which each patient acted as their own control. Whereas 25 patients had a positive response to VAD, 37 patients had a response to PAD ≤ partial remission (PR) (p = 0.023). Using the more stringent response level of very good PR (VGPR) the results favored the PAD regimen very significantly (p = 0.006) (McNemars test). Similar results were seen using paired M-protein levels from individual patient comparisons. As the PAD regimen was subsequently adopted as the re-induction therapy in the British Society for Blood and Marrow Transplantation/United Kingdom Myeloma Forum Myeloma X (Intensive) trial, now concluded, we have retrospectively analyzed the findings from both studies. Comparison of response rates and adverse effects of patients having had previous autologous transplantation (Cohort 1) with the corresponding data from Myeloma X showed close correlation. These findings provide evidence that rapid results may be obtained in the evaluation of newly introduced, and potentially highly effective, anti-tumour agents by direct comparison to the response to the immediately preceding standard regimen, particularly in relatively resistant tumours.

17.
Clin Teach ; 17(3): 286-291, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31452336

RESUMEN

BACKGROUND: Ward rounds are a fundamental part of hospital culture and teaching on rounds has a long tradition. Yet evidence points towards increasing difficulties in delivering ward round education in complex heath care settings. Drawing on the literature and gaps identified in our own hospital setting we hypothesised that a tool for structuring ward rounds could improve the educational experience on rounds without adding a time burden to already busy consultants. METHODS: We used a developmental evaluation approach to develop a framework and evaluate a tool for improving ward round education. The ward round framework STIC (Set, Target, Inspect and Close) and ward round tool was developed through an iterative process of reviewing and piloting in a clinical department and was evaluated against Moore's outcome levels drawing on quantitative and qualitative data. Surveys of consultants were used to quantify uptake, acceptability and usefulness of the ward round tool. Focus groups of trainee doctors evaluated their experience of ward round education. RESULTS: The majority of consultants used the ward round tool and found it accessible, and useful to enhance education, without extending ward round time. Trainee doctors had seen the ward round tool in use and reflected that it provided structure, focused their learning opportunities, gave clarity to the agenda and provided closure. Unintended benefits were seen for enhanced team work. CONCLUSIONS: We present a structured framework STIC and tool for ward rounds that incorporates education, which is acceptable to consultants and is perceived to enhance education for trainees and to strengthen team work. Understanding our framework STIC and our ward round tool's applicability in other settings, scalability and impact and the perspective of patients, would be valuable extensions of this work. We present a structured framework STIC and tool for ward rounds that incorporates education, which is acceptable to consultants and is perceived to enhance education for trainees and to strengthen team work.


Asunto(s)
Rondas de Enseñanza , Consultores , Grupos Focales , Hospitales , Humanos , Encuestas y Cuestionarios
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