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This study is aimed at establishing the outcome of RSTI exposure to acetaminophen based on a decision tree algorithm for the first time. This study used the National Poison Data System (NPDS) to conduct a six-year retrospective cohort analysis, which included 4522 individuals. The patients had a mean age of 26.75 ± 16.3 years (1-89). 3160 patients (70%) were females. Most patients had intentional exposure to acetaminophen. Almost all the patients had acetaminophen exposure via ingestion. In addition, 400 (8.8%) experienced major outcomes, 1500 (33.2%) experienced moderate outcomes, and 2622 (58%) of the patients experienced mild ones. The decision tree model performed well in the training and test groups. In the test group, the accuracy was 0.813, precision of 0.827, recall being 0.798, specificity 0.898, and an F1 score 0.80. In the training group, accuracy was 0.831, recall was 0.825, precision was 0.837, specificity was 0.90, and F1 score was 0.829. Our results showed that serum liver enzymes being present at elevated levels (Alanine aminotransferase (ALT), Aspartate aminotransferase (AST) greater than 1000 U/L followed by ALT, AST between 100 and 1000 U/L), prothrombin time (PT) prolongation, bilirubin increase, renal failure, confusion, age, hypotension, other coagulopathy (such as partial thromboplastin time (PTT) prolongation), acidosis, and electrolyte abnormality were the effective factors in determining the outcomes in these patients. The decision tree algorithm is a dependable method for establishing the prognosis of patients who have been exposed to RSTI acetaminophen and can be used throughout the patients' hospitalization period.
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Analgésicos no Narcóticos , Enfermedad Hepática Inducida por Sustancias y Drogas , Venenos , Femenino , Humanos , Niño , Adolescente , Adulto Joven , Adulto , Masculino , Acetaminofén/efectos adversos , Analgésicos no Narcóticos/efectos adversos , Estudios Retrospectivos , Enfermedad Hepática Inducida por Sustancias y Drogas/diagnóstico , Enfermedad Hepática Inducida por Sustancias y Drogas/epidemiología , Enfermedad Hepática Inducida por Sustancias y Drogas/etiología , Algoritmos , Árboles de Decisión , Ingestión de AlimentosRESUMEN
Background: Previous research has emphasized the importance of efficient ventilation in suppressing COVID-19 transmission in indoor spaces, yet suitable ventilation rates have not been suggested. Materials and Methods: This study investigated the impacts of mechanical, natural, single-sided, cross-ventilation, and three mask types (homemade, surgical, N95) on COVID-19 spread across eight common indoor settings. Viral exposure was quantified using a mass balance calculation of inhaled viral particles, accounting for initial viral load, removal via ventilation, and mask filtration efficiency. Results: Results demonstrated that natural cross-ventilation significantly reduced viral load, decreasing from 10,000 to 0 viruses over 15 minutes in a 100 m2 space by providing ~1325 m3/h of outdoor air via two 0.6 m2 openings at 1.5 m/s wind speed. In contrast, single-sided ventilation only halved viral load at best. Conclusion: Natural cross-ventilation with masks effectively suppressed airborne viruses, lowering potential infections and disease transmission. The study recommends suitable ventilation rates to reduce COVID-19 infection risks in indoor spaces.
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Lead is one of the most toxic heavy metals in the environment. The present review aimed to highlight hazardous pollution sources, management, and review symptoms of lead poisonings in various parts of the world. The present study summarized the information available from case reports and case series studies from 2009 to March 2020 on the lead pollution sources and clinical symptoms. All are along with detoxification methods in infants, children, and adults. Our literature compilation includes results from 126 studies on lead poisoning. We found that traditional medication, occupational exposure, and substance abuse are as common as previously reported sources of lead exposure for children and adults. Ayurvedic medications and gunshot wounds have been identified as the most common source of exposure in the United States. However, opium and occupational exposure to the batteries were primarily seen in Iran and India. Furthermore, neurological, gastrointestinal, and hematological disorders were the most frequently occurring symptoms in lead-poisoned patients. As for therapeutic strategies, our findings confirm the safety and efficacy of chelating agents, even for infants. Our results suggest that treatment with chelating agents combined with the prevention of environmental exposure may be an excellent strategy to reduce the rate of lead poisoning. Besides, more clinical studies and long-term follow-ups are necessary to address all questions about lead poisoning management.
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Suministros de Energía Eléctrica/efectos adversos , Salud Global , Intoxicación por Plomo/epidemiología , Medicina Ayurvédica/efectos adversos , Adicción al Opio/epidemiología , Opio/efectos adversos , Heridas por Arma de Fuego/epidemiología , Adolescente , Adulto , Quelantes/uso terapéutico , Niño , Preescolar , Contaminación de Medicamentos , Medicina Basada en la Evidencia , Femenino , Humanos , India/epidemiología , Lactante , Recién Nacido , Irán/epidemiología , Intoxicación por Plomo/diagnóstico , Intoxicación por Plomo/tratamiento farmacológico , Masculino , Exposición Profesional/efectos adversos , Adicción al Opio/diagnóstico , Pronóstico , Medición de Riesgo , Factores de Riesgo , Estados Unidos/epidemiología , Heridas por Arma de Fuego/diagnósticoAsunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Antivirales/uso terapéutico , Betacoronavirus/patogenicidad , Infecciones por Coronavirus/tratamiento farmacológico , Síndrome de Liberación de Citoquinas/prevención & control , Neumonía Viral/tratamiento farmacológico , COVID-19 , Infecciones por Coronavirus/diagnóstico por imagen , Síndrome de Liberación de Citoquinas/diagnóstico por imagen , Interacciones Huésped-Patógeno/efectos de los fármacos , Humanos , Losartán/uso terapéutico , Pandemias , Neumonía Viral/diagnóstico por imagen , Pronóstico , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Telmisartán/uso terapéutico , Tomografía Computarizada por Rayos X , Valsartán/uso terapéuticoRESUMEN
Bupropion is widely used for the treatment of major depressive disorder and for smoking cessation assistance. Unfortunately, there are no practical systems to assist clinicians or poison centres in predicting outcomes based on clinical features. Hence, the purpose of this study was to use a decision tree approach to inform early diagnosis of outcomes secondary to bupropion overdose. This study utilized a dataset from the National Poison Data System, a 6-year retrospective cohort study on toxic exposures and patient outcomes. A machine learning algorithm (decision tree) was applied to the dataset using the sci-kit-learn library in Python. Shapley Additive exPlanations (SHAP) were used as an explainable method. Comparative analysis was performed using random forest (RF), Gradient Boosting classification, eXtreme Gradient Boosting, Light Gradient Boosting (LGM) and voting ensembling. ROC curve and precision-recall curve were used to analyse the performance of each model. LGM and RF demonstrated the highest performance to predict outcome of bupropion exposure. Multiple seizures, conduction disturbance, intentional exposure, and confusion were the most influential factors to predict the outcome of bupropion exposure. Coma and seizure, including single, multiple and status, were the most important factors to predict major outcomes.
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Bupropión , Trastorno Depresivo Mayor , Humanos , Estados Unidos/epidemiología , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/epidemiología , Estudios Retrospectivos , Convulsiones , Aprendizaje Automático , Árboles de DecisiónRESUMEN
Snakebite is a relatively common health condition in Iran with a diverse snake fauna, especially in tropical southern and mountainous western areas of the country with a plethora of snake species. The list of medically important snakes, circumstances and effects of their bite, and necessary medical care require critical appraisal and should be updated regularly. This study aims to review and map the distributions of medically important snake species of Iran, re-evaluate their taxonomy, review their venomics, describe the clinical effects of envenoming, and discuss medical management and treatment, including the use of antivenom. Nearly 350 published articles and 26 textbooks with information on venomous and mildly venomous snake species and snakebites of Iran, were reviewed, many in Persian (Farsi) language, making them relatively inaccessible to an international readership. This has resulted in a revised updated list of Iran's medically important snake species, with taxonomic revisions of some, compilation of their morphological features, remapping of their geographical distributions, and description of species-specific clinical effects of envenoming. Moreover, the antivenom manufactured in Iran is discussed, together with treatment protocols that have been developed for the hospital management of envenomed patients.
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Mordeduras de Serpientes , Animales , Mordeduras de Serpientes/tratamiento farmacológico , Antivenenos/uso terapéutico , Irán , SerpientesRESUMEN
BACKGROUND: With diabetes incidence growing globally and metformin still being the first-line for its treatment, metformin's toxicity and overdose have been increasing. Hence, its mortality rate is increasing. For the first time, we aimed to study the efficacy of machine learning algorithms in predicting the outcome of metformin poisoning using two well-known classification methods, including support vector machine (SVM) and decision tree (DT). METHODS: This study is a retrospective cohort study of National Poison Data System (NPDS) data, the largest data repository of poisoning cases in the United States. The SVM and DT algorithms were developed using training and test datasets. We also used precision-recall and ROC curves and Area Under the Curve value (AUC) for model evaluation. RESULTS: Our model showed that acidosis, hypoglycemia, electrolyte abnormality, hypotension, elevated anion gap, elevated creatinine, tachycardia, and renal failure are the most important determinants in terms of outcome prediction of metformin poisoning. The average negative predictive value for the decision tree and SVM models was 92.30 and 93.30. The AUC of the ROC curve of the decision tree for major, minor, and moderate outcomes was 0.92, 0.92, and 0.89, respectively. While this figure of SVM model for major, minor, and moderate outcomes was 0.98, 0.90, and 0.82, respectively. CONCLUSIONS: In order to predict the prognosis of metformin poisoning, machine learning algorithms might help clinicians in the management and follow-up of metformin poisoning cases.
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Metformina , Máquina de Vectores de Soporte , Algoritmos , Árboles de Decisión , Humanos , Pronóstico , Estudios Retrospectivos , Estados Unidos/epidemiologíaRESUMEN
After the spread of Covid 19 worldwide, the use of cloth masks increased significantly due to a shortage of medical masks. Meanwhile, there were different opinions about the effectiveness of these masks and, so far, no study has been done to find the best fabric masks. This study reviews and summarizes all studies related to fabric masks' effectiveness and various fabrics against coronavirus. This systematic review is based on PRISMA rules. Two researchers separately examined three databases: PubMed, Scopus, and Web of Science. Laboratory and clinical studies were included. After extracting the articles, their quality was assessed with the Joanna Briggs Institute (JBI) tool. In addition to efficacy, other factors, including the penetration of masks, pressure drop, and quality factor, were examined to select the best fabrics. Of the 42 studies selected, 39 were laboratory studies, and 3 were clinical studies. Among the various fabrics examined, cotton quilt 120 thread per inch (TPI), copy paper (bonded), hybrid of cotton with chiffon/ silk, and flannel filtration were found to have over 90% effectiveness in the particle size range of Covid-19. The results and comparison of different factors (pressure drop, filtration efficacy, penetration, filtration quality, and fit factor have been evaluated) showed that among different fabrics, hybrid masks, 2-layered cotton quilt, 2-layered 100% cotton, cotton flannel, and hairy tea towel + fleece sweater had the best performance. Clinical studies have not explicitly examined cloth masks' effectiveness in Covid-19, so the effectiveness of these types of masks for Covid 19 is questionable, and more studies are needed.
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COVID-19 , Máscaras , Filtración , Humanos , SARS-CoV-2 , TextilesRESUMEN
INTRODUCTION: Acetaminophen (paracetamol, APAP) poisoning is a prominent global cause of drug-induced liver injury. While N-acetylcysteine (NAC) is an effective antidote, it has therapeutic limitations in massive overdose or delayed presentation. The objective is to comprehensively review the literature on fomepizole as a potential adjunct antidote for acetaminophen toxicity. METHODS: A scoping review was performed using standardized search terms from inception through July 2021. RESULTS: Reports on fomepizole as a therapeutic adjunct for APAP toxicity span heterogeneous types of evidence. Eleven preclinical studies (in vitro and animal), fourteen case reports/series, and one human volunteer study were included. Fomepizole's action is mediated by inhibition of CYP2E1 to prevent oxidant stress generation, and inhibition of c-Jun N-terminal kinase (JNK) to decrease amplification of oxidant stress signaling to mitochondria. Studies have shown a reduction in oxidative metabolites likely by shunting metabolism away from CYP2E1 and a resultant decrease in liver injury in animals, independent of CYP2E1 interactions. Fomepizole has been linked to few adverse effects. CONCLUSION: Based on in vitro and animal studies, and bolstered by case reports, fomepizole likely offers benefit as an adjunct antidote for APAP toxicity, however this remains to be shown in a human trial. NAC remains the standard of care antidote, but given that fomepizole is approved and generally safe, it may be considered for APAP toxicity as off-label use by experienced clinicians, in rare circumstances associated with increased risk of hepatotoxicity despite standard NAC dosing. The marginal clinical benefit of fomepizole adjunct therapy beyond NAC monotherapy remains to be clearly defined, and routine use for APAP overdose is premature based on current evidence.
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Acetaminofén/toxicidad , Antídotos/uso terapéutico , Enfermedad Hepática Inducida por Sustancias y Drogas/tratamiento farmacológico , Fomepizol/uso terapéutico , HumanosRESUMEN
The global COVID-19 pandemic has affected the world's population by causing changes in behavior, such as social distancing, masking, restricting people's movement, and evaluating existing medication as potential therapies. Many pre-existing medications such as tocilizumab, ivermectin, colchicine, interferon, and steroids have been evaluated for being repurposed to use for the treatment of COVID-19. None of these agents have been effective except for steroids and, to a lesser degree, tocilizumab. Ivermectin has been one of the suggested repurposed medications which exhibit an in vitro inhibitory activity on SARS-CoV-2 replication. The most recommended dose of ivermectin for the treatment of COVID-19 is 150-200 µg/kg twice daily. As ivermectin adoption for COVID-19 increased, the Food and Drug Administration (FDA) issued a warning on its use during the pandemic. However, the drug remains of interest to clinicians and has shown some promise in observational studies. This narrative reviews the toxicological profile and some potential therapeutic effects of ivermectin. Based on the current dose recommendation, ivermectin appears to be safe with minimum side effects. However, serious questions remain about the effectiveness of this drug in the treatment of patients with COVID-19.
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Antivirales/uso terapéutico , Tratamiento Farmacológico de COVID-19 , Reposicionamiento de Medicamentos , Ivermectina/efectos adversos , Ivermectina/uso terapéutico , Antivirales/efectos adversos , Antivirales/farmacocinética , Ensayos Clínicos como Asunto , Humanos , Ivermectina/administración & dosificación , Ivermectina/farmacocinética , Profilaxis Pre-Exposición/métodosRESUMEN
INTRODUCTION: Snakebite is an urgent, unmet global medical need causing significant morbidity and mortality worldwide. Varespladib is a potent inhibitor of venom secretory phospholipase A2 (sPLA2) that can be administered orally via its prodrug, varespladib-methyl. Extensive preclinical data support clinical evaluation of varespladib as a treatment for snakebite envenoming (SBE). The protocol reported here was designed to evaluate varespladib-methyl for SBE from any snake species in multiple geographies. METHODS AND ANALYSIS: BRAVO (Broad-spectrum Rapid Antidote: Varespladib Oral for snakebite) is a multicenter, randomized, double-blind, placebo-controlled, phase 2 study to evaluate the safety, tolerability, and efficacy of oral varespladib-methyl plus standard of care (SoC) vs. SoC plus placebo in patients presenting with acute SBE by any venomous snake species. Male and female patients 5 years of age and older who meet eligibility criteria will be randomly assigned 1:1 to varespladib-methyl or placebo. The primary outcome is the Snakebite Severity Score (SSS) that has been modified for international use. This composite outcome is based on the sum of the pulmonary, cardiovascular, nervous, hematologic, and renal systems components of the updated SSS. ETHICS AND DISSEMINATION: This protocol was submitted to regulatory authorities in India and the US. A Clinical Trial No Objection Certificate from the India Central Drugs Standard Control Organisation, Drug Controller General-India, and a Notice to Proceed from the US Food and Drug Administration have been obtained. The study protocol was approved by properly constituted, valid institutional review boards or ethics committees at each study site. This study is being conducted in compliance with the April 1996 ICH Guidance for Industry GCP E6, the Integrated Addendum to ICH E6 (R2) of November 2016, and the applicable regulations of the country in which the study is conducted. The trial is registered on Clinical trials.gov, NCT#04996264 and Clinical Trials Registry-India, 2021/07/045079 000062.
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Fosfolipasas A2 Secretoras , Mordeduras de Serpientes , Humanos , Masculino , Femenino , Mordeduras de Serpientes/tratamiento farmacológico , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto , Ensayos Clínicos Fase II como AsuntoRESUMEN
The aim of this study was to evaluate the blood levels of folic acid, vitamin B12, and 25-hydroxyvitamin D (25-OHD) in patients with lead poisoning compared with control subjects in Eastern Iran. This analytical case-control study was conducted on 40 lead-poisoned patients who were referred to Imam Reza Hospital in Birjand from 2018 to 2019. Blood samples were collected from an additional 40 individuals without lead poisoning as a control group. The results indicated that the mean vitamin B12, vitamin D, and folic acid levels for the case group were 356.5 ± 200.1 pg/ml, 24.38 ± 9.5 ng/ml, and 7.4 ± 3.7 ng/ml, respectively. Mean folic acid level in the case group was significantly lower than control group (7.4 ng/ml vs. 12.70 pg/ml, P = 0.001), whereas the mean of the vitamin D levels at the case group was significantly higher than that of the control group (24.3 ng/ml vs. 20.1 ng/ml, P = 0.03). Moreover, mean vitamin B12 levels were significantly lower in the case group in comparison with the control group (356.5 pg/ml vs. 500.8 pg/ml) (P < 0.001). In the control group, 3 patients had folic acid below normal level (< 6 ng/mL) while 12 cases had folic acid below normal (P < 0.05). Also, none of the control group had low vitamin B12 concentrations (< 180 pg/ml), while 7 cases had vitamin b12 below normal (P < 0.05). Our results suggest that lead may induce folate and vitamin B12 dysregulation. Although we found that vitamin D levels were insufficient in both case and control groups, they were significantly higher in the case group. The interpretation of this result is unclear given inconsistent literature reports on this relationship.
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Intoxicación por Plomo , Vitamina B 12 , Estudios de Casos y Controles , Ácido Fólico , Homocisteína , Humanos , Irán , Vitamina D , VitaminasRESUMEN
Utilization of marijuana as a medicinal agent is becoming increasingly popular, and so far, 25 states have legalized it for medical purposes. However, there is emerging evidence that marijuana use can result in cardiovascular side effects, such as rhythm abnormalities, syncope/dizziness, and myocardial infarction, among others. Further, there are currently no stringent national standards or approval processes, like Food and Drug Administration (FDA) evaluation, in place to assess medical marijuana products. This review includes the largest up-to-date pooled population of patients with exposure to marijuana and reported cardiovascular effects. Although purported as benign by many seeking to advance the use of marijuana as an adjunctive medical therapy across the country, marijuana is associated with its own set of cardiovascular risks and deserves further definitive study and the same level of scrutiny we apply in research of all other types of medications. When used as a medicinal agent, marijuana should be regarded accordingly, and both clinical providers and patients must be aware of potential adverse effects associated with its use for early recognition and management.
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Enfermedades Cardiovasculares/inducido químicamente , Marihuana Medicinal/efectos adversos , Humanos , Estados UnidosRESUMEN
Today, COVID-19 is spreading around the world. Information about its mechanism, prognostic factors, and management is minimal. COVID-19, as a human disease, has several identifying phases. Physicians of patients with COVID-19 may be interested in knowing whether opioid use disorder may affect their patients' course or prognosis. This information may be crucial when considering the opioid epidemic in the US and other parts of the world. Opioid use at high doses and over several months duration can mitigate the immune system's function, which may complicate the course of COVID-19 disease. Potential suppression of parts of the immune response may be important in prevention, clinical support, and therapeutic use of medications in various phases of the COVID-19. Specifically, opioid use disorders via an inhalation route may enhance the "late hyper-inflammatory phase" or result in end-organ damage. It is well established that opioids decrease ventilation as their effect on the medullary respiratory centers increases the risk of pneumonia. This increased risk has been associated with immune-suppressive opioids. The ultimate role of opioids in COVID-19 is not clear. This paper endorses the need for clinical studies to decipher the role and impact of chronic opioid use on viral diseases such as COVID-19.
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COVID-19/epidemiología , Trastornos Relacionados con Opioides/epidemiología , COVID-19/inmunología , COVID-19/mortalidad , Humanos , Huésped Inmunocomprometido/inmunología , Trastornos Relacionados con Opioides/inmunología , Pandemias , SARS-CoV-2RESUMEN
INTRODUCTION: Studies comprehensively summarizing the impact of tramadol use on glucose homeostasis are very sparse. Thus, the present study was performed to collect and summarize the latest information about this issue in a systematic way. AREAS COVERED: An exhaustive literature search was carried out using relevant keywords. Web of Sciences, PubMed, Scopus, and Google scholar were interrogated until 30 June 2019. Case-control, cohort, cross-sectional, clinical trial, case report, and animal studies that focused on the objective of the study were retrieved. This review summarizes the results of 761 papers on glycemic changes due to tramadol exposure. Thirty-six publications reported hypoglycemia and 17 hyperglycemia during tramadol use. Twenty-two studies either reported normal blood glucose concentrations, or did not observe any difference in the blood glucose levels following tramadol use. Finally, hypoglycemia was reported in diabetic individuals exposed to tramadol in 12 studies. EXPERT OPINION: The data suggest that primarily hypoglycemia but some degree of hyperglycemia has been reported with tramadol use. Importantly, all studies on tramadol use in diabetes reported hypoglycemia. Tramadol-induced hypoglycemia may be severe in some cases. The risk of alterations in glucose homeostasis accompanying tramadol exposure indicates time importance of careful blood glucose monitoring during tramadol use.
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Analgésicos Opioides/efectos adversos , Glucemia/efectos de los fármacos , Tramadol/efectos adversos , Analgésicos Opioides/administración & dosificación , Animales , Glucemia/análisis , Humanos , Hiperglucemia/inducido químicamente , Hipoglucemia/inducido químicamente , Tramadol/administración & dosificaciónRESUMEN
This case report describes the effects of an envenomation from one of the most infrequently encountered species of rattlesnake in the United States, Crotalus willardi willardi (C. w. willardi), the Arizona Ridge-nosed Rattlesnake. A previously healthy 57-year-old male sustained a bite to his non-dominant hand from a C. w. willardi. The most pronounced effect from the envenomation was edema and progression of edema that extended from his hand to the mid bicep. He also experienced erythema and tenderness to palpation in the affected limb, and some diminished range of motion in the hand. He expressed only minimal pain. Other than a mildly positive D-Dimer and leukocytosis, he had no significant hematologic effects and no systemic effects. He was treated with standard doses of Crotalidae Polyvalent Immune Fab (Ovine). He reported complete recovery from the envenomation within three days of the bite. Although envenomation from rattlesnakes is somewhat common in Arizona, knowing the exact species of snake is not. Confirmed documentation is exceedingly rare as most people do not recognize the different rattlesnake species. In addition, some species of rattlesnake (such as C. w. willardi) are especially reclusive and found only in isolated mountainous regions. Being able to confirm an envenomation by C. w. willardi would require not only someone knowledgeable in herpetology, but also, preferably, photographic evidence. This case has both.
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Antivenenos/uso terapéutico , Venenos de Crotálidos/toxicidad , Crotalus/clasificación , Fragmentos Fab de Inmunoglobulinas/uso terapéutico , Mordeduras de Serpientes , Animales , Arizona , Humanos , Masculino , Persona de Mediana EdadRESUMEN
BACKGROUND: Crotalidae Polyvalent Immune Fab (Ovine) has been the only antivenom commercially available in the US since 2007 for treatment of Crotalinae envenomation. Late coagulopathy can occur or recur after clearance of Fab antivenom, often after hospital discharge, lasting in some cases more than 2 weeks. There have been serious, even fatal, bleeding complications associated with recurrence phenomena. Frequent follow-up is required, and additional intervention or hospitalization is often necessary. F(ab')2 immunoglobulin derivatives have longer plasma half life than do Fab. We hypothesized that F(ab')2 antivenom would be superior to Fab in the prevention of late coagulopathy following treatment of patients with Crotalinae envenomation. METHODS: We conducted a prospective, double-blind, randomized clinical trial, comparing late coagulopathy in snakebitten patients treated with F(ab')2 with maintenance doses [F(ab')2/F(ab')2], or F(ab')2 with placebo maintenance doses [F(ab')2/placebo], versus Fab with maintenance doses [Fab/Fab]. The primary efficacy endpoint was coagulopathy (platelet count < 150 K/mm(3), fibrinogen level < 150 mg/dL) between end of maintenance dosing and day 8. RESULTS: 121 patients were randomized at 18 clinical sites and received at least one dose of study drug. 114 completed the study. Of these, 11/37 (29.7%) in the Fab/Fab cohort experienced late coagulopathy versus 4/39 (10.3%, p < 0.05) in the F(ab')2/F(ab')2 cohort and 2/38 (5.3%, p < 0.05) in the F(ab')2/placebo cohort. The lowest heterologous protein exposure was with F(ab')2/placebo. No serious adverse events were related to study drug. In each study arm, one patient experienced an acute serum reaction and one experienced serum sickness. CONCLUSIONS: In this study, management of coagulopathic Crotalinae envenomation with longer-half-life F(ab')2 antivenom, with or without maintenance dosing, reduced the risk of subacute coagulopathy and bleeding following treatment of envenomation.