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1.
Acta Haematol ; : 1-5, 2024 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-39004080

RESUMEN

INTRODUCTION: Distinguishing disseminated intravascular coagulation (DIC) from the coagulopathy of liver disease represents a common clinical challenge. Here, we evaluated the utility of two diagnostic tools frequently used to differentiate between these conditions: factor VIII (FVIII) levels and the International Society on Thrombosis and Hemostasis (ISTH) DIC score. METHODS: To this end, we conducted a retrospective chart review of patients with DIC, liver disease, or both. Multiple logistic regression was performed, and receiver operating characteristic curves were generated to calculate the area under curve (AUC) for distinguishing DIC in the setting of liver disease. RESULTS: Among 123 patients with DIC, liver disease, or liver disease plus DIC, FVIII levels did not differ significantly. ISTH scores were lower in patients with DIC than in liver disease with or without DIC. Addition of several laboratory parameters to the ISTH score, including mean platelet volume, FV, FVIII, international normalized ratio, and activated partial thromboplastin time, improved AUC for distinguishing DIC in liver disease from liver disease alone (AUC = 0.76; p < 0.0001). CONCLUSION: We conclude that FVIII levels do not distinguish DIC from liver disease, and ISTH DIC scores are not predictive of DIC in patients with liver disease. Inclusion of additional lab variables within the ISTH DIC score may aid in identifying DIC in patients with liver disease.

2.
Trials ; 25(1): 424, 2024 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-38943204

RESUMEN

BACKGROUND: Most patients starting chronic in-center hemodialysis (HD) receive conventional hemodialysis (CHD) with three sessions per week targeting specific biochemical clearance. Observational studies suggest that patients with residual kidney function can safely be treated with incremental prescriptions of HD, starting with less frequent sessions and later adjusting to thrice-weekly HD. This trial aims to show objectively that clinically matched incremental HD (CMIHD) is non-inferior to CHD in eligible patients. METHODS: An unblinded, parallel-group, randomized controlled trial will be conducted across diverse healthcare systems and dialysis organizations in the USA. Adult patients initiating chronic hemodialysis (HD) at participating centers will be screened. Eligibility criteria include receipt of fewer than 18 treatments of HD and residual kidney function defined as kidney urea clearance ≥3.5 mL/min/1.73 m2 and urine output ≥500 mL/24 h. The 1:1 randomization, stratified by site and dialysis vascular access type, assigns patients to either CMIHD (intervention group) or CHD (control group). The CMIHD group will be treated with twice-weekly HD and adjuvant pharmacologic therapy (i.e., oral loop diuretics, sodium bicarbonate, and potassium binders). The CHD group will receive thrice-weekly HD according to usual care. Throughout the study, patients undergo timed urine collection and fill out questionnaires. CMIHD will progress to thrice-weekly HD based on clinical manifestations or changes in residual kidney function. Caregivers of enrolled patients are invited to complete semi-annual questionnaires. The primary outcome is a composite of patients' all-cause death, hospitalizations, or emergency department visits at 2 years. Secondary outcomes include patient- and caregiver-reported outcomes. We aim to enroll 350 patients, which provides ≥85% power to detect an incidence rate ratio (IRR) of 0.9 between CMIHD and CHD with an IRR non-inferiority of 1.20 (α = 0.025, one-tailed test, 20% dropout rate, average of 2.06 years of HD per patient participant), and 150 caregiver participants (of enrolled patients). DISCUSSION: Our proposal challenges the status quo of HD care delivery. Our overarching hypothesis posits that CMIHD is non-inferior to CHD. If successful, the results will positively impact one of the highest-burdened patient populations and their caregivers. TRIAL REGISTRATION: Clinicaltrials.gov NCT05828823. Registered on 25 April 2023.


Asunto(s)
Estudios Multicéntricos como Asunto , Diálisis Renal , Humanos , Resultado del Tratamiento , Factores de Tiempo , Investigación sobre la Eficacia Comparativa , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios de Equivalencia como Asunto , Estados Unidos , Fallo Renal Crónico/terapia , Fallo Renal Crónico/diagnóstico
3.
Am J Kidney Dis ; 2024 Jun 06.
Artículo en Inglés | MEDLINE | ID: mdl-38851445

RESUMEN

The global burden of kidney disease is increasing, paralleled by a rising number of natural and man-made crises. During these tumultuous times, accessing vital health care resources becomes challenging, posing significant risks to individuals, particularly those with kidney disease. This review delves into the impact of crises on kidney disease, with a particular focus on acute kidney injury (AKI), kidney failure, and kidney transplant. Patients experiencing crush injuries leading to AKI may encounter delayed diagnosis due to the chaotic nature of disasters and limited availability of resources. In chronic crises such as conflicts, patients with kidney failure are particularly affected, and deviations from dialysis standards are unfortunately common, impacting morbidity and mortality rates. Additionally, crises also disrupt access to kidney transplants, potentially compromising transplant outcomes. This review underscores the critical importance of preparedness measures and proactive management for kidney disease in crisis settings. Collaborative efforts among government bodies, rescue teams, health care providers, humanitarian agencies, and nongovernmental organizations are imperative to ensure equitable and reasonable care for kidney disease patients during times of crises, with the aim of saving lives and improving outcomes.

7.
J Allergy Clin Immunol Pract ; 11(11): 3383-3390.e3, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37454926

RESUMEN

BACKGROUND: It remains unclear whether patients with asthma and/or chronic obstructive pulmonary disease (COPD) are at increased risk for severe coronavirus disease 2019 (COVID-19). OBJECTIVE: Compare in-hospital COVID-19 outcomes among patients with asthma, COPD, and no airway disease. METHODS: A retrospective cohort study was conducted on 8,395 patients admitted with COVID-19 between March 2020 and April 2021. Airway disease diagnoses were defined using International Classification of Diseases, 10th Revision codes. Mortality and sequential organ failure assessment (SOFA) scores were compared among groups. Logistic regression analysis was used to identify and adjust for confounding clinical features associated with mortality. RESULTS: The median SOFA score in patients without airway disease was 0.32 and mortality was 11%. In comparison, asthma patients had lower SOFA scores (median 0.15; P < .01) and decreased mortality, even after adjusting for age, diabetes, and other confounders (odds ratio 0.65; P = .01). Patients with COPD had higher SOFA scores (median 0.86; P < .01) and increased adjusted odds of mortality (odds ratio 1.40; P < .01). Blood eosinophil count of 200 cells/µL or greater, a marker of type 2 inflammation, was associated with lower mortality across all groups. Importantly, patients with asthma showed improved outcomes even after adjusting for eosinophilia, indicating that noneosinophilic asthma was associated with protection as well. CONCLUSIONS: COVID-19 severity was increased in patients with COPD and decreased in those with asthma, eosinophilia, and noneosinophilic asthma, independent of clinical confounders. These findings suggest that COVID-19 severity may be influenced by intrinsic immunological factors in patients with airway diseases, such as type 2 inflammation.


Asunto(s)
Asma , COVID-19 , Diabetes Mellitus Tipo 2 , Eosinofilia , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Estudios Retrospectivos , COVID-19/complicaciones , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Asma/diagnóstico , Inflamación , Eosinofilia/complicaciones
8.
Acta Haematol ; 146(4): 287-292, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37166332

RESUMEN

Patients with acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) often receive antibacterial prophylaxis. Antibacterial agents can cause elevations in the prothrombin time and international normalized ratio (INR). The impact of prophylactic antibacterials on the coagulation profiles and bleeding risk in patients with AML/MDS is unknown. We evaluated patients with AML or MDS who were being admitted to the hospital. The cohort was divided into two groups of patients: (1) those receiving and (2) those not receiving prophylactic antibacterials, at the time of admission. We conducted a retrospective cohort study of adult patients with AML/MDS admitted to Yale-New Haven Hospital between 2015-2019. The study was approved by the Yale Institutional Review Board. Inclusion criteria included patients >18 years old with a diagnosis of AML or MDS admitted to the hospital. We identified 150 individual patient encounters with active AML/MDS admitted to Yale-New Haven of which 32 occurred while on and 118 while off antibacterial prophylaxis. Median duration of pre-admission antibacterial exposure was 2 (range: 0.07-24) months. Patients on antibacterial prophylaxis had higher INR (median 1.14 vs. 1.03, p = 0.0002), and higher partial thromboplastin time prolongation (median 26.5 vs. 24.3, p < 0.0014), than patients without antibacterial prophylaxis. Patients without antibacterial prophylaxis had higher rates of bleeding using the ISTH-defined criteria (24.6% vs. 6.3%, p = 0.043), including higher rates of ISTH major (2 vs. 0) and clinically relevant bleeding (9 vs. 0). Patients with AML/MDS on antibacterial prophylaxis were more likely to have an abnormal coagulation profile when compared with their counterparts not on prophylaxis. Conversely, rates of bleeding were higher in patients not on prophylaxis. These data suggest that prophylactic antibacterials do not increase bleeding risk in patients with AML/MDS.


Asunto(s)
Leucemia Mieloide Aguda , Síndromes Mielodisplásicos , Adulto , Humanos , Adolescente , Estudios Retrospectivos , Leucemia Mieloide Aguda/complicaciones , Leucemia Mieloide Aguda/tratamiento farmacológico , Síndromes Mielodisplásicos/complicaciones , Síndromes Mielodisplásicos/tratamiento farmacológico , Síndromes Mielodisplásicos/diagnóstico
9.
Eur Clin Respir J ; 10(1): 2174640, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36815942

RESUMEN

Background: Patients hospitalized with COVID-19 are at significant risk for superimposed bacterial pneumonia. However, diagnosing superinfection is challenging due to its clinical resemblance to severe COVID-19. We therefore evaluated whether the immune biomarker, procalcitonin, could facilitate the diagnosis of bacterial superinfection. Methods: We retrospectively identified 185 patients hospitalized with severe COVID-19 who underwent lower respiratory culture; 85 had evidence of bacterial superinfection. Receiver operating characteristic curve and area under the curve (AUC) analyses were performed to assess the utility of procalcitonin for diagnosing superinfection. Results: This approach demonstrated that procalcitonin measured at the time of culture was incapable of distinguishing patients with bacterial infection (AUC, 0.52). The AUC not affected by exposure to antibiotics, treatment with immunomodulatory agents, or timing of procalcitonin measurement. Conclusion: Static measurement of procalcitonin does not aid in the diagnosis of superinfection in severe COVID-19.

10.
Am J Respir Cell Mol Biol ; 68(1): 75-89, 2023 01.
Artículo en Inglés | MEDLINE | ID: mdl-36125351

RESUMEN

The mechanisms by which excessive systemic activation of adaptive T lymphocytes, as in cytokine release syndrome (CRS), leads to innate immune cell-mediated acute lung injury (ALI) or acute respiratory distress syndrome, often in the absence of any infection, remains unknown. Here, we investigated the roles of IFN-γ and IL-17A, key T-cell cytokines significantly elevated in patients with CRS, in the immunopathogenesis of CRS-induced extrapulmonary ALI. CRS was induced in wild-type (WT), IL-17A- and IFN-γ knockout (KO) human leukocyte antigen-DR3 transgenic mice with 10 µg of the superantigen, staphylococcal enterotoxin B, given intraperitoneally. Several ALI parameters, including gene expression profiling in the lungs, were studied 4, 24, or 48 hours later. Systemic T-cell activation with staphylococcal enterotoxin B resulted in robust upregulation of several chemokines, S100A8/A9, matrix metalloproteases, and other molecules implicated in tissue damage, granulocyte as well as agranulocyte adhesion, and diapedesis in the lungs as early as 4 hours, which was accompanied by subsequent neutrophil/eosinophil lung infiltration and severe ALI in IFN-γ KO mice. These pathways were significantly underexpressed in IL-17A KO mice, which manifested mildest ALI and intermediate in WT mice. Neutralization of IFN-γ worsened ALI in WT and IL-17A KO mice, whereas neutralizing IL-17A did not mitigate lung injury in IFN-γ KO mice, suggesting a dominant protective role for IFN-γ in ALI and that IL-17A is dispensable. Ruxolitinib, a Janus kinase inhibitor, increased ALI severity in WT mice. Thus, our study identified novel mechanisms of ALI in CRS and its differential modulation by IFN-γ and IL-17A.


Asunto(s)
Lesión Pulmonar Aguda , Interleucina-17 , Humanos , Ratones , Animales , Síndrome de Liberación de Citoquinas , Interferón gamma , Citocinas , Pulmón/patología , Lesión Pulmonar Aguda/patología , Ratones Noqueados , Ratones Endogámicos C57BL
11.
Artículo en Inglés | MEDLINE | ID: mdl-36483405

RESUMEN

Among 124 older adults with advanced cancer who were hospitalized with pneumonia, 7.3% met criteria for postobstructive pneumonia. There were no differences in antibiotic duration, antibiotic spectrum, 30-day and 90-day readmissions, or mortality between those with and without postobstructive pneumonia. Bacteria were identified in 5 patients with postobstructive pneumonia.

12.
Kidney360 ; 3(11): 1980-1990, 2022 11 24.
Artículo en Inglés | MEDLINE | ID: mdl-36514412

RESUMEN

Continuous renal replacement therapy (CRRT) is a form of renal replacement therapy that is used in modern intensive care units (ICUs) to help manage acute kidney injury (AKI), end stage kidney disease (ESKD), poisonings, and some electrolyte disorders. CRRT has transformed the care of patients in the ICU over the past several decades. In this setting, it is important to recognize CRRT-associated complications but also up-to-date management of these complications. Some of these complications are minor, but others may be more significant and even life-threatening. Some CRRT complications may be related to dialysis factors and others to specific patient factors. Our overarching goal in this article is to review and discuss the most significant CRRT-related complications at the different stage of management of CRRT. With the advent of newer solutions, there have been newer complications as well.


Asunto(s)
Lesión Renal Aguda , Terapia de Reemplazo Renal Continuo , Humanos , Diálisis Renal/efectos adversos , Terapia de Reemplazo Renal/efectos adversos , Lesión Renal Aguda/etiología , Unidades de Cuidados Intensivos
13.
bioRxiv ; 2022 May 29.
Artículo en Inglés | MEDLINE | ID: mdl-35665001

RESUMEN

Acute respiratory distress syndrome (ARDS) is a life-threatening clinical condition defined by rapid onset respiratory failure following acute lung injury (ALI). Its increased incidence due to COVID-19 and high mortality rate (∻40%) make the study of ARDS pathogenesis a crucial research priority. CRTH2 is a G protein-coupled receptor with established roles in type 2 immunity and well-characterized inhibitors. Prior studies have shown it also promotes neutrophilic inflammation, indicating that CRTH2 inhibition may be a potential therapeutic strategy for ARDS. To test this hypothesis, we first examined the expression pattern of CRTH2 on murine neutrophils. We found it is expressed on neutrophils, but only after extravasation into the lung. Next, we showed that extravasated lung neutrophils generate inflammatory responses upon stimulation with the CRTH2-specific agonist DK-PGD2, as demonstrated by reactive oxygen species (ROS) production. This response was abrogated in CRTH2 KO neutrophils. Inhibition of CRTH2 with fevipiprant suppressed baseline ROS production, indicating an autocrine PGD2-CRTH2 signaling loop. We then evaluated the role of CRTH2 in vivo using a murine model of LPS-induced ALI. Despite the pro-inflammatory effects of CRTH2 on neutrophils in vitro, we observed worsening of lung injury in CRTH2-deficient mice in terms of neutrophilic inflammation, vascular leak, and survival. Bulk RNAseq of lung tissue indicated an impairment in type 2 immune signaling; qPCR and ELISA confirmed downregulation of the key type 2 effector cytokine, IL-4. Thus, CRTH2 appears to play a dual role in ALI, directly promoting neutrophil effector responses, but indirectly suppressing lung injury and neutrophilic inflammation through type 2 immunity. These findings reveal a novel protective function for CRTH2 during lung injury and argue against the use of CRTH2 inhibitors in ARDS.

14.
medRxiv ; 2022 Apr 05.
Artículo en Inglés | MEDLINE | ID: mdl-35411344

RESUMEN

Patients hospitalized with COVID-19 are at significant risk for superimposed bacterial pneumonia. However, diagnosing superinfection is challenging due to its clinical resemblance to severe COVID-19. We therefore evaluated whether the immune biomarker, procalcitonin, could facilitate the diagnosis of bacterial superinfection. To do so, we identified 185 patients with severe COVID-19 who underwent lower respiratory culture; 85 had superinfection. Receiver operating characteristic curve analysis showed that procalcitonin at the time of culture was incapable of distinguishing patients with bacterial infection (AUC, 0.52). We conclude that static measurement of procalcitonin does not aid in the diagnosis of superinfection in severe COVID-19.

15.
Ann Am Thorac Soc ; 18(7): 1087-1097, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-34242148

RESUMEN

Pneumonia causes a significant burden of disease worldwide. Although all populations are at risk of pneumonia, those at extremes of age and those with immunosuppressive disorders, underlying respiratory disease, and critical illness are particularly vulnerable. Although clinical practice guidelines addressing the management and treatment of pneumonia exist, few of the supporting studies focus on the crucial contributions of the host in pneumonia pathogenesis and recovery. Such essential considerations include the host risk factors that lead to susceptibility to lung infections; biomarkers reflecting the host response and the means to pursue host-directed pneumonia therapy; systemic effects of pneumonia on the host; and long-term health outcomes after pneumonia. To address these gaps, the Pneumonia Working Group of the Assembly on Pulmonary Infection and Tuberculosis led a workshop held at the American Thoracic Society meeting in May 2018 with overarching objectives to foster attention, stimulate research, and promote funding for short-term and long-term investigations into the host contributions to pneumonia. The workshop involved participants from various disciplines with expertise in lung infection, pneumonia, sepsis, immunocompromised patients, translational biology, data science, genomics, systems biology, and clinical trials. This workshop report summarizes the presentations and discussions and important recommendations for future clinical pneumonia studies. These recommendations include establishing consensus disease and outcome definitions, improved phenotyping, development of clinical study networks, standardized data and biospecimen collection and protocols, and development of innovative trial designs.


Asunto(s)
Neumonía , Consenso , Enfermedad Crítica , Humanos , Huésped Inmunocomprometido , Neumonía/terapia , Informe de Investigación , Estados Unidos
16.
J Clin Med ; 10(6)2021 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-33799741

RESUMEN

Acute kidney injury (AKI) is a common clinical syndrome characterized by rapid impairment of kidney function. The incidence of AKI and its severe form AKI requiring dialysis (AKI-D) has been increasing over the years. AKI etiology may be multifactorial and is substantially associated with increased morbidity and mortality. The outcome of AKI-D can vary from partial or complete recovery to transitioning to chronic kidney disease, end stage kidney disease, or even death. Predicting outcomes of patients with AKI is crucial as it may allow clinicians to guide policy regarding adequate management of this problem and offer the best long-term options to their patients in advance. In this manuscript, we will review the current evidence regarding the determinants of AKI outcomes, focusing on AKI-D.

18.
Chest ; 158(4): e191-e196, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33036118

RESUMEN

CASE PRESENTATION: A 62-year-old nonsmoking woman with no medical history initially presented with a 3-month history of rash. A painful, erythematous exanthem had progressed from her forehead, cheeks, and upper chest to her eyes (heliotrope rash) and hands, primarily involving the extensor surface finger joints with prominent digital ulceration.


Asunto(s)
Enfermedades Pulmonares Intersticiales/diagnóstico , Autoanticuerpos/sangre , Progresión de la Enfermedad , Exantema/complicaciones , Femenino , Humanos , Hipoxia/complicaciones , Helicasa Inducida por Interferón IFIH1/inmunología , Enfermedades Pulmonares Intersticiales/sangre , Enfermedades Pulmonares Intersticiales/complicaciones , Enfermedades Pulmonares Intersticiales/inmunología , Neoplasias Pulmonares/complicaciones , Persona de Mediana Edad , Úlcera Cutánea/complicaciones , Factores de Tiempo
19.
Thorax ; 75(11): 974-981, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32826284

RESUMEN

INTRODUCTION: Procalcitonin expression is thought to be stimulated by bacteria and suppressed by viruses via interferon signalling. Consequently, during respiratory viral illness, clinicians often interpret elevated procalcitonin as evidence of bacterial coinfection, prompting antibiotic administration. We sought to evaluate the validity of this practice and the underlying assumption that viral infection inhibits procalcitonin synthesis. METHODS: We conducted a retrospective cohort study of patients hospitalised with pure viral infection (n=2075) versus bacterial coinfection (n=179). The ability of procalcitonin to distinguish these groups was assessed. In addition, procalcitonin and interferon gene expression were evaluated in murine and cellular models of influenza infection. RESULTS: Patients with bacterial coinfection had higher procalcitonin than those with pure viral infection, but also more severe disease and higher mortality (p<0.001). After matching for severity, the specificity of procalcitonin for bacterial coinfection dropped substantially, from 72% to 61%. In fact, receiver operating characteristic curve analysis showed that procalcitonin was a better indicator of multiple indices of severity (eg, organ failures and mortality) than of coinfection. Accordingly, patients with severe viral infection had elevated procalcitonin. In murine and cellular models of influenza infection, procalcitonin was also elevated despite bacteriologic sterility and correlated with markers of severity. Interferon signalling did not abrogate procalcitonin synthesis. DISCUSSION: These studies reveal that procalcitonin rises during pure viral infection in proportion to disease severity and is not suppressed by interferon signalling, in contrast to prior models of procalcitonin regulation. Applied clinically, our data suggest that procalcitonin represents a better indicator of disease severity than bacterial coinfection during viral respiratory infection.


Asunto(s)
Biomarcadores/metabolismo , Neumonía Viral/metabolismo , Polipéptido alfa Relacionado con Calcitonina/metabolismo , Anciano , Anciano de 80 o más Años , Animales , Coinfección , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Neumonía Bacteriana/metabolismo , Neumonía Bacteriana/mortalidad , Neumonía Viral/mortalidad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad
20.
Am J Physiol Lung Cell Mol Physiol ; 319(4): L661-L669, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32783617

RESUMEN

The past two decades have witnessed a resurgence in neutrophil research, inspired in part by the discovery of neutrophil extracellular traps (NETs) and their myriad roles in health and disease. Within the lung, dysregulation of neutrophils and NETosis have been linked to an array of diseases including pneumonia, cystic fibrosis, acute respiratory distress syndrome (ARDS), chronic obstructive pulmonary disease (COPD), and severe asthma. However, our understanding of pathologic neutrophil responses in the lung remains incomplete. Two methodologic issues have contributed to this gap: first, an emphasis on studying neutrophils from blood rather than the lung and second, the technical difficulties of interrogating neutrophil responses in mice, which has largely restricted basic murine research to specialized laboratories. To address these limitations, we have developed a suite of techniques for studying neutrophil effector functions specifically in the mouse lung. These include ex vivo assays for phagocytosis and NETosis using bronchoalveolar neutrophils and in situ evaluation of NETosis in a murine model of pneumonia. Throughout, we have prioritized technical ease and robust, quantitative readouts. We hope these assays will help to standardize research on lung neutrophils and improve accessibility to this burgeoning field.


Asunto(s)
Trampas Extracelulares/metabolismo , Neutrófilos/patología , Fagocitosis/fisiología , Enfermedad Pulmonar Obstructiva Crónica/patología , Animales , Modelos Animales de Enfermedad , Pulmón/patología , Ratones , Neumonía/diagnóstico , Neumonía/patología , Síndrome de Dificultad Respiratoria/diagnóstico , Síndrome de Dificultad Respiratoria/patología
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