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OBJECTIVES: To identify the etiology of peripheral eosinophilia in a large pediatric population and to develop a diagnostic algorithm to help guide diagnosis and management of peripheral eosinophilia in the outpatient pediatric population. STUDY DESIGN: We performed a retrospective chart review of children presenting to Texas Children's Hospital in Houston with peripheral eosinophilia between January 1, 2011 and December 31, 2019. Eosinophilia was classified as mild (absolute eosinophil count [AEC] >500 and <1500 cells/µL), moderate (AEC >1500 and <4500 cells/µL), or severe (AEC >4500 cells/µL). Demographic information and diagnostic workup data were collected. RESULTS: A total of 771 patients aged <18 years were evaluated. The most common cause of eosinophilia was allergy (n = 357; 46%), with atopy (n = 296) and drug reaction (n = 54) the most common subcauses. This was followed by unknown etiology (n = 274; 36%), infectious causes (n = 72; 9%), and eosinophilic disorders (n = 47; 6%). Many patients with an unknown cause (n = 202; 74%) had limited or no follow-up testing. CONCLUSIONS: More information on the etiology of pediatric eosinophilia and workup data could help identify the causes. This study provides important information on the evaluation of eosinophilia in the US pediatric population, including a diagnostic algorithm to guide primary care pediatricians.
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Eosinofilia , Hipersensibilidade , Humanos , Criança , Eosinófilos , Estudos Retrospectivos , Eosinofilia/diagnóstico , Eosinofilia/etiologia , Contagem de Leucócitos , Hipersensibilidade/complicaçõesRESUMO
Existing acute febrile illness (AFI) surveillance systems can be leveraged to identify and characterize emerging pathogens, such as SARS-CoV-2, which causes COVID-19. The US Centers for Disease Control and Prevention collaborated with ministries of health and implementing partners in Belize, Ethiopia, Kenya, Liberia, and Peru to adapt AFI surveillance systems to generate COVID-19 response information. Staff at sentinel sites collected epidemiologic data from persons meeting AFI criteria and specimens for SARS-CoV-2 testing. A total of 5,501 patients with AFI were enrolled during March 2020-October 2021; >69% underwent SARS-CoV-2 testing. Percentage positivity for SARS-CoV-2 ranged from 4% (87/2,151, Kenya) to 19% (22/115, Ethiopia). We show SARS-CoV-2 testing was successfully integrated into AFI surveillance in 5 low- to middle-income countries to detect COVID-19 within AFI care-seeking populations. AFI surveillance systems can be used to build capacity to detect and respond to both emerging and endemic infectious disease threats.
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COVID-19 , Doenças Transmissíveis , Estados Unidos , Humanos , COVID-19/epidemiologia , SARS-CoV-2 , Teste para COVID-19 , Febre/epidemiologiaRESUMO
Validated glass bead sterilization protocols to effectively sterilize rodent surgical instruments after bacterial exposure (for example, cecal contamination) are lacking. To refine current approaches, we added either a multienzyme detergent, neutral pH detergent, or chlorhexidine scrub step before glass bead sterilization of forceps or needle drivers exposed to cecal contents. We exposed sets of forceps and needle drivers to cecal contents, which were then air dried for 3 min. Immediately after, the instruments were wiped several times with a clean, dry paper towel. The contaminated tips were soaked in either a multienzyme or neutral pH detergent (t = 5 min), chlorhexidine scrub (t = 2 min), or no pretreatment solution. To further increase debris removal, instruments (from all groups) were brushed using a clean toothbrush. The nonpretreatment instruments were briefly soaked in saline before brushing. After being rinsed with sterile water, all instruments were exposed to a glass bead sterilizer for 60 s at 500 °F (260 °C). Sets were then swabbed for bacterial culturing. Swabs were plated onto either sheep blood agar (n = 23) or chocolate agar (n = 20) for aerobic culturing or Brucella agar (n = 20) for anaerobic culturing. A subset of instruments was sampled to determine organic material presence after treatment using an ATP luminometer (n = 21). Multiple agar types and bioluminescence were used to more deeply evaluate tool sterility and to differentiate the relative effectiveness of each protocol. From the saline group, only one pair of forceps yielded growth on Brucella agar, and 2 pairs yielded growth on chocolate agar. No other bacterial growth was observed. The use of a pretreatment agent also lowered overall organic contamination levels in needle drivers compared with using only saline. These results indicate that brushing instruments to mechanically remove debris from instruments is paramount to ensure sterility. However, a best practice would be to also use one of the pretreatment options used in this study.
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Contaminação de Equipamentos , Esterilização , Esterilização/métodos , Animais , Contaminação de Equipamentos/prevenção & controle , Instrumentos Cirúrgicos/microbiologia , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Detergentes , Clorexidina/farmacologia , VidroRESUMO
BACKGROUND: Isolated psychiatric symptoms can be the initial symptom of pediatric anti-N-methyl-d-aspartate (NMDA) receptor autoimmune encephalitis (pNMDARE). Here we report on the prevalence of isolated psychiatric symptoms in pNMDARE. We also assess whether initial neurodiagnostic tests (brain magnetic resonance imaging [MRI], electroencephalography [EEG], and/or cerebrospinal fluid [CSF] white blood cell count) are abnormal in children with isolated psychiatric symptoms and pNMDARE. METHODS: This multicenter retrospective cohort study from CONNECT (Conquering Neuroinflammation and Epilepsies Consortium) from 14 institutions included children under age 18 years who were diagnosed with pNMDARE. Descriptive statistics using means, medians, and comparisons for continuous versus discrete data was performed. RESULTS: Of 249 children included, 12 (5%) had only psychiatric symptoms without other typical clinical features of autoimmune encephalitis at presentation. All but one (11 of 12 = 92%) had at least one abnormal finding on initial ancillary testing: eight of 12 (67%) had an abnormal EEG, six of 12 (50%) had an abnormal MRI, and five of 12 (42%) demonstrated CSF pleocytosis. The single patient with a normal MRI, EEG, and CSF profile had low positive CSF NMDA antibody (titer of 1:1), and symptoms improved without immunotherapy. CONCLUSIONS: Isolated first-episode psychiatric symptoms in pNMDARE are uncommon, and the majority of children will exhibit additional neurodiagnostic abnormalities. Delaying immunotherapy in a child with isolated psychiatric symptoms and normal neurodiagnostic testing may be warranted while awaiting confirmatory antibody testing.
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Encefalite Antirreceptor de N-Metil-D-Aspartato , Eletroencefalografia , Humanos , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Encefalite Antirreceptor de N-Metil-D-Aspartato/complicações , Criança , Masculino , Feminino , Estudos Retrospectivos , Adolescente , Imageamento por Ressonância Magnética , Transtornos Mentais/etiologia , Transtornos Mentais/epidemiologia , Pré-EscolarRESUMO
BACKGROUND: We describe a cohort of children with severe myelin oligodendrocyte glycoprotein (MOG)-IgG-associated cerebral cortical encephalitis (CCE), manifesting with bilateral cortical cytotoxic edema and critical neurological illness. METHODS: We retrospectively reviewed our pediatric MOG antibody-associated disease (MOGAD) database and identified patients with specific radiographic pattern of bilateral, multifocal cortical cytotoxic lesions. We collected demographic, clinical, and outcomes data from these patients and compared select variables with radiographically distinct cerebral MOGAD syndromes (case-control analysis). We assessed the correlation of quantitative clinical variables with severity/outcomes measures using simple linear regression. RESULTS: Sixty-five of 88 total MOGAD cases had cerebral disease, and six of 88 met inclusion criteria for fulminant CCE (f-CCE). Age range was 2 to 7 years; five of six were male. Six of six were critically ill with severe encephalopathy and seizures, two of six required barbiturate coma, and two of six required invasive intracranial pressure monitoring. Six of six required treatment escalation beyond steroids. Four of six had favorable outcome; two of six had moderate-severe disability. Compared with other cerebral MOGAD cases (n = 59), children with f-CCE were more likely to have critical illness and poor neurological outcomes scores. Neurofilament light chain and treatment latency positively correlated with intensive care unit length of stay and outcomes scores; cerebrospinal fluid (CSF) white blood cell count and neutrophil-to-lymphocyte ratio did not. CONCLUSIONS: Pediatric CCE with bilateral cytotoxicity is associated with more fulminant disease and worse outcomes than other cerebral MOGAD syndromes.
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Encefalopatias , Encefalite , Masculino , Humanos , Feminino , Glicoproteína Mielina-Oligodendrócito , Estudos Retrospectivos , Síndrome , Encefalite/diagnóstico por imagem , Fenótipo , Oligodendroglia , AutoanticorposRESUMO
BACKGROUND: Toxocariasis, caused the by dog and cat roundworm, is one of the most common zoonotic helminth infections in the United States and can lead to severe lifelong morbidity in children. Although historical seroprevalence studies have identified a high frequency of toxocariasis regionally in the United States, there are few studies linking epidemiology and clinical disease in children. The study objective was to examine the contemporary epidemiology of pediatric toxocariasis within an endemic US region. METHODS: We conducted an epidemiologic study analyzing children diagnosed with toxocariasis presenting to a tertiary pediatric hospital in Texas from 2010 to 2021. We examined risk factors and performed a geospatial analysis, including a comparative analysis of human cases and locations of surrendered infected stray animals in the same region. RESULTS: Children diagnosed with toxocariasis were most commonly of Hispanic/Latino ethnicity (30/46; 65%), white race (41/45; 91%) and receiving Medicaid (34/44, 77%). Many infected children had contact with dogs or cats. Ocular toxocariasis was associated with a lack of peripheral eosinophilia ( P < 0.001). No other Toxocara syndromes were associated with defined absolute eosinophil count levels. Post-treatment resolution of eosinophilia was variable, ranging from 1 to 172 weeks. A Toxocara hotspot was identified in northeast Houston, comprising one of the lowest median household incomes in the region. CONCLUSIONS: Toxocariasis is a devastating zoonotic infection in children living in the US. As it is not a reportable disease, the true burden remains unknown. It is critical to increase awareness of toxocariasis to direct public health interventions and ultimately reduce Toxocara -induced morbidity in US children.
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Doenças do Gato , Doenças do Cão , Toxocaríase , Estados Unidos , Humanos , Criança , Animais , Gatos , Cães , Saúde Pública , Toxocaríase/epidemiologia , Hospitais Pediátricos , Estudos Soroepidemiológicos , Zoonoses/epidemiologiaRESUMO
Anti-N-methyl-d-aspartate receptor autoimmune encephalitis (NMDAR AE) is an antibody-mediated neurological disorder that may be caused by post-herpes simplex virus-1 meningoencephalitis (HSV ME) and ovarian teratomas, although most pediatric cases are idiopathic. We sought to evaluate if other infections precede NMDAR AE by conducting a single-center, retrospective, case-control study of 86 pediatric cases presenting to Texas Children's Hospital between 2006 and 2022. HSV ME (HSV-1 and HSV-2) was a significantly more common preceding infection in the experimental group compared to control patients with idiopathic intracranial hypertension, while there was no difference in remote HSV infection between the two groups. Recent Epstein-Barr virus infection was evident in 8/42 (19%) tested experimental patients in comparison to 1/25 (4%) tested control patients which provided evidence for a genuine measure of effect but was not statistically significant due to small sample size (p = 0.07). The other 25 infectious etiologies were not different among the two groups and not all variables were clinically indicated or obtained in every subject, highlighting the need for future standardized, multi-institutional studies on underlying infectious precursors of autoimmune encephalitis.
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West Nile virus (WNV) is a neurotropic flavivirus that can cause acute febrile illness leading to neuroinvasive disease. Depression is a well-described outcome following infection, but the underlying pathogenic mechanisms are unknown. Proinflammatory cytokines play important roles in WNV infection, but their role in depression post-WNV remains unstudied. This research aimed to retrospectively evaluate associations between proinflammatory cytokines and new onset depression in a WNV cohort. Participants with asymptomatic WNV infection were significantly less likely to report new onset depression when compared to those with symptomatic disease. Participants with encephalitis and obesity were significantly more likely to report new onset depression post-infection. Based on univariate analysis of 15 antiviral or proinflammatory cytokines, depression was associated with elevated MCP-1 and decreased TNFα, whereas G-CSF was significantly elevated in those with a history of neuroinvasive WNV. However, no cytokines were statistically significant after adjusting for multiple comparisons using the Bonferroni method. While symptomatic WNV infection, encephalitis, and obesity were associated with new onset depression following infection, the role of proinflammatory cytokines requires additional studies. Further research involving paired acute-convalescent samples, larger sample sizes, and additional data points would provide additional insight into the impact of the inflammatory response on WNV-mediated depression.
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Emerging vector-borne and zoonotic pathogens can cause neuroinvasive disease in children; utilization of appropriate diagnostic testing can be low, hindering diagnosis and clinical management of these cases. We must understand factors that influence healthcare providers' decisions to order diagnostic testing. We reviewed medical charts for pediatric meningitis and encephalitis patients (90 days-18 years) between 2010 and 2017 and analyzed variables associated with testing for known neuroinvasive zoonotic pathogens in the southern United States: West Nile virus (WNV), Bartonella spp., and Rickettsia spp. Among 620 cases of meningitis and encephalitis, ~1/3 (n = 209, 34%) were tested for WNV. Fewer cases were tested for Bartonella (n = 77, 12%) and Rickettsia (n = 47, 8%). Among those tested, 14 (7%) WNV, 7 (9%) Bartonella, and 6 (13%) Rickettsia cases were identified. Factors predicting testing were similar between all agents: clinical presentation of encephalitis, focal neurologic symptoms, new onset seizure, and decreased Glasgow Coma Scale on admission. Cases with a history of arthropod contact were more likely to be tested; however, we did not see an increase in testing during the summer season, when vector exposure typically increases. While our test utilization was higher than that reported in other studies, improvement is needed to identify zoonotic causes of neuroinvasive diseases.
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The Acute Febrile Illness (AFI) Surveillance Network in Belize is a country-wide active surveillance program aimed at diagnosing vector-borne, respiratory, and enteric pathogens among patients presenting to 11 participating hospitals and clinics with new onset fever. This study describes the epidemiology of dengue virus (DENV) infections in Belize diagnosed through AFI surveillance in 2020. Of the 894 patients enrolled and PCR-tested for DENV in this period, 44 DENV-positive cases (5%) were identified. All four DENV serotypes were detected, with two cases testing positive for DENV serotype 4, which is the first report of this serotype in Belize since 2004. The majority of DENV cases (66%) were diagnosed in the Belize District, which contains the largest urban center in the country (Belize City). Positive cases were detected between January 2020 and September 2020, with the majority (89%) diagnosed during the dry season between January and April, unlike years prior when cases were more often diagnosed during the wet season. Clinical signs and symptoms varied slightly between DENV serotypes. Active surveillance of DENV among AFI cases provides insight into the epidemiologic and clinical characteristics of DENV in Belize. This information is important for informing public health interventions to mitigate DENV transmission.
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Vírus da Dengue , Dengue , Viroses , Belize , Dengue/diagnóstico , Dengue/epidemiologia , Vírus da Dengue/genética , Febre/epidemiologia , HumanosRESUMO
Tick-borne diseases in the United States, including ehrlichiosis, represent a growing public health problem. The purpose of this study was to examine the contemporary epidemiology of human ehrlichiosis in Texas by analyzing cases reported to the Texas Department of State Health Services. In Texas, 101 cases of ehrlichiosis were reported during 2008-2017. We observed geographic grouping of cases as well as an increasing trend of reported cases occurring annually from 2009 to 2017. Notably, 27 cases occurred in 2008 in south Texas with unique patient characteristics in that they were younger, less likely to be hospitalized, and presented with disease earlier in the year than typically seen. Our findings highlight the importance of disease awareness and prevention of tick bites as well as further investigation into transmission risk and future disease patterns.
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Ehrlichiose/epidemiologia , Humanos , Incidência , Texas/epidemiologiaRESUMO
BACKGROUND: Meningitis is associated with substantial morbidity and mortality, particularly in the first three months of life. METHODS: We conducted a retrospective review of patients <90 days of age with meningitis at Texas Children's Hospital from 2010-2017. Cases were confirmed using the National Healthcare Safety Network (NHSN) definition of meningitis. RESULTS: Among 694 infants with meningitis, the most common etiology was viral (n = 351; 51%), primarily caused by enterovirus (n = 332; 95%). A quarter of cases were caused by bacterial infections (n = 190; 27%). The most common cause of bacterial meningitis was group B Streptococcus (GBS, n = 60; 32%), followed by Gram-negative rods other than E. coli (n = 40; 21%), and E. coli (n = 37; 19%). The majority of Gram-negative organisms (63%) were resistant to ampicillin, and nearly one-fourth of Gram-negative rods (23%) other than E. coli and 2 (6%) E. coli isolates were resistant to third-generation cephalosporins. Significant risk factors for bacterial meningitis were early preterm birth and the Black race. CONCLUSIONS: Enteroviruses most commonly caused viral meningitis in infants; GBS was the most common bacterial cause despite universal screening and intrapartum prophylaxis. The emergence of MRSA and resistance to third-generation cephalosporins in Gram-negative bacterial meningitis challenges the options for empirical antimicrobial therapy.
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Hookworm is an intestinal parasite that infects nearly 230 million people, with another 5.1 billion at risk, especially in poverty-stricken tropical and subtropical regions. Pregnancy is an especially vulnerable time for hookworm infection because of its effect on both maternal and subsequently fetal health. A systematic review and meta-analysis was conducted. The meta-analysis was performed on the association between maternal hookworm and maternal anemia, as well as maternal hookworm coinfection with malaria. The prevalence of hookworm ranged from 1% to 78% in pregnant women, whereas malaria prevalence ranged from 11% to 81%. Pregnant women with hookworm infection were more likely to have anemia (combined odds ratio [cOR] 2.55 [2.20, 2.96], P < 0.001). In addition, pregnant woman with hookworm were more likely to have malaria coinfection (cOR 1.60 [1.38, 1.86], P < 0.001). Other effects on maternal and child health were investigated and summarized without systematic review or meta-analysis because of the limited study numbers. Despite current deworming recommendations in pregnant women, heavy hookworm burden, coinfection with malaria, and subsequent anemia persist. Although this is likely due, in part, to a lack of implementation of preventive chemotherapy, additional interventions such as health education, proper waste management, or linking malaria and soil-transmitted helminth treatment and prevention programs may also be needed. Further investigations on maternal-child outcomes as a result of hookworm infection during pregnancy will highlight public health interventional targets to reduce morbidity in pregnant women and children globally.
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Anemia/epidemiologia , Coinfecção , Infecções por Uncinaria/epidemiologia , Malária/epidemiologia , Saúde Materna , Complicações Parasitárias na Gravidez/epidemiologia , Ancylostomatoidea , Anemia/complicações , Anemia/parasitologia , Animais , Estudos de Coortes , Estudos Transversais , Feminino , Educação em Saúde , Infecções por Uncinaria/complicações , Infecções por Uncinaria/parasitologia , Humanos , Malária/complicações , Malária/parasitologia , Gravidez , Complicações Parasitárias na Gravidez/parasitologia , Saúde PúblicaRESUMO
BACKGROUND AND OBJECTIVES: Encephalitis can result in neurologic morbidity and mortality in children. Newly recognized infectious and noninfectious causes of encephalitis have become increasingly important over the past decade. METHODS: We retrospectively reviewed medical records from pediatric patients in Houston diagnosed with encephalitis in both an urban and rural catchment area between 2010 and 2017. We conducted an investigation to understand the etiology, clinical characteristics, and diagnostic testing practices in this population. RESULTS: We evaluated 231 patients who met the case definition of encephalitis, among which 42% had no recognized etiology. Among those with an identified etiology, the most common were infectious (73; 31%), including viral (n = 51; 22%), with the most frequent being West Nile virus (WNV; n = 12), and bacterial (n = 19; 8%), with the most frequent being Bartonella henselae (n = 7). Among cases of autoimmune encephalitis (n = 60; 26%), the most frequent cause was anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis (n = 31). Autoimmune causes were seen more commonly in female (P < .01) patients. Testing for herpes simplex virus and enterovirus was nearly universal; testing for anti-NMDAR encephalitis, WNV, and Bartonella was less common. CONCLUSIONS: WNV was the most common infectious cause of encephalitis in our pediatric population despite lower testing frequency for WNV than herpes simplex virus or enterovirus. Increasing testing for anti-NMDAR encephalitis resulted in frequent identification of cases. Increased awareness and testing for WNV and Bartonella would likely result in more identified causes of pediatric encephalitis. Earlier etiologic diagnosis of encephalitides may lead to improve clinical outcomes.
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Encefalite Antirreceptor de N-Metil-D-Aspartato/epidemiologia , Doença da Arranhadura de Gato/epidemiologia , Encefalite/epidemiologia , Doença de Hashimoto/epidemiologia , Febre do Nilo Ocidental/epidemiologia , Adolescente , Encefalite Antirreceptor de N-Metil-D-Aspartato/diagnóstico , Encefalite Antirreceptor de N-Metil-D-Aspartato/imunologia , Autoanticorpos/imunologia , Doença da Arranhadura de Gato/diagnóstico , Doença da Arranhadura de Gato/imunologia , Criança , Pré-Escolar , Estudos de Coortes , Doenças Transmissíveis/diagnóstico , Doenças Transmissíveis/epidemiologia , Doenças Transmissíveis/imunologia , Encefalite/diagnóstico , Encefalite/imunologia , Feminino , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/imunologia , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Febre do Nilo Ocidental/diagnóstico , Febre do Nilo Ocidental/imunologiaRESUMO
Background: Despite advances in targeted kinase inhibitor development for patients with medullary thyroid cancer (MTC), most patients develop resistance and would benefit from alternative approaches. Immune-based therapies are now considered for patients with progressive MTC. This study is the first comprehensive assessment of the immune milieu, immune-suppressive molecules, and potential tumor antigens in patients with MTC. Methods: Primary and/or regionally metastatic tumor tissues from 46 patients with MTC were screened for immune infiltrates by using standard immunohistochemistry (IHC) and further analyzed by multispectral imaging for T cell and myeloid markers. RNASeq expression profiling was performed in parallel. RNASeq, targeted sequencing, and IHC techniques identified cancer-associated mutations and MTC-enriched proteins. Results: Organized immune infiltration was observed in 49% and 90% of primary and metastatic tumors, respectively. CD8+ cells were the dominant T cell subtype in most samples, while CD163+ macrophages were most frequent among myeloid infiltrates. PD-1+ T cells were evident in 24% of patients. Myeloid subsets were largely major histocompatibility complex II (MHCII-), suggesting a dysfunctional phenotype. Expression profiling confirmed enrichment in T cell, macrophage, and inflammatory profiles in a subset of samples. PD-L1 was expressed at low levels in a small subset of patients, while the immune regulatory molecules CD155 and CD47 were broadly expressed. Calcitonin, GRP, HIST1H4E, NOMO3, and NPIPA2 were highly and specifically expressed in MTC. Mutations in tumor suppressors, PTEN and p53, and mismatch repair genes, MSH2 and MSH6, may be relevant to disease progression and antigenicity. Conclusions: This study suggests that MTC is a more immunologically active tumor that has been previously reported. Patients with advanced MTC should be screened for targetable antigens and immune checkpoints to determine their eligibility for current clinical trials. Additional studies are necessary to fully characterize the antigenic potential of MTC and may encourage the development of adoptive T cells therapies for this rare tumor.
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Antígenos de Neoplasias/metabolismo , Carcinoma Neuroendócrino/imunologia , RNA-Seq , Neoplasias da Glândula Tireoide/imunologia , Calcitonina/metabolismo , Carcinoma Neuroendócrino/metabolismo , Ensaios Clínicos como Assunto , Análise Mutacional de DNA , Progressão da Doença , Perfilação da Expressão Gênica , Humanos , Sistema Imunitário , Imuno-Histoquímica , Leucócitos/metabolismo , Macrófagos/metabolismo , Proteína 2 Homóloga a MutS/metabolismo , Mutação , Receptores Virais/metabolismo , Neoplasias da Glândula Tireoide/metabolismo , Tireoidite Autoimune/metabolismo , Estados UnidosRESUMO
Methicillin-resistant Staphylococcus aureus (MRSA) health care-associated infections (HAIs) are a cause of extended hospitalizations and escalating health care costs. We typed 49 MRSA HAIs and their corresponding admission nasal MRSA isolates to determine strain-relatedness and better define the role of anterior nares in the causation of HAI and the value of decolonization. Based on repetitive extragenic palindromic sequencing polymerase chain reaction results, the majority of our patients possibly acquired MRSA HAI from nonnasal sources (36 out of 49; 74%). Among the remaining patients (13 out of 49; 26%) the nasal and clinical HAI isolates matched, indicating potential benefit of decolonization among this subsegment of patients. These findings may be relevant to institutions such as Veterans Health Administration hospitals that already have universal screening programs but are looking at ways to further reduce MRSA HAI incidence.