2358. Acute Flaccid Myelitis Among Hospitalized Children in Texas, 2016

Background

This is a multisite study of cases of acute flaccid myelitis (AFM) in Texas during the year 2016 among 6 children’s hospitals. AFM is a newly recognized and poorly understood disease. Information related particularly to pathogenesis, treatment, and recovery are lacking.

Methods

Children age 0–18 years admitted with AFM defined as acute onset limb weakness with spinal cord lesions on MRI primarily involving gray matter during January 1–December 31, 2016, were reviewed. Abstracted information included demographics, presentation, laboratory findings, treatments, and long-term outcomes up to 18 months after onset of weakness (range 3.5–18 months; median 15 months).

Results

22 patients from 5 hospitals were included. Median age was 4.9 years. Upper extremity involvement was common (77%), with all extremities being involved in 36%. Enterovirus D68 was identified in 3 cases. Other pathogens identified included human parechovirus (n = 2), human herpesvirus 6 (n = 1), non-D68 enterovirus (n = 2), rhinovirus (n = 1), Mycoplasma pneumoniae (n = 1), Bartonella henselae (n = 1), and influenza B (n = 1). In total, 32% recovered fully in strength and function, and 45% had full recovery of function. 18% remain completely dependent on caregivers. All extremities were involved in 8 patients. 6 had significant residual weakness, ranging from flaccidity in one extremity to complete caregiver dependence. One was lost to follow-up after discharge. None of the three patients with Enterovirus D-68 made a full recovery, and all three remain largely dependent on caregivers. Treatments varied, but most commonly included methylprednisolone (n = 14) or intravenous immunoglobulin (IVIG) (n = 13). All cases of full recovery were treated with steroids, IVIG, or both. 4 patients were not treated; 2 with eventual recovery of function (Figure 1). Response to IVIG and steroids was variable; no harm was noted in response to IVIG (Figure 2).

Conclusion

Our findings overall show more promising outcomes than those seen in the 2014 nationwide outbreak of AFM. Specific treatments were not associated with better outcomes. IVIG appeared to be helpful in several cases and, at the very least, was not harmful. Patients with all extremities involved and/or enterovirus D68 appear to have poorer outcomes.

Disclosures

All authors: No reported disclosures.

Antimicrobial activity of Agaricus brasiliensis on Plasmopara viticola and its effect on the induction of resistance to the control of downy mildew on ‘Isabel Precoce’

ABSTRACT: Agaricus brasiliensis include bioactive compounds that can act as antibiotics, bacteriostatic, fungistatic and nematostatic substances. In this sense, this study aimed to evaluate the effect of a single application of aqueous mycelial suspension (AMS) of A. brasiliensis in control of downy mildew (Plasmopara viticola) and resistance induction in ‘Isabel Precoce’ grapevines under greenhouse conditions. Treatments consisted of three doses of 1%, 5%, 10%, 15% and 20% AMS A. brasiliensis, as well as treatment with acibenzolar-S-methyl (ASM). The variables analyzed were: sporangiospore germination, disease severity, represented by the area under the disease progress curve (AUDPC), catalase enzyme activity, peroxidase and polyphenol. The 10%, 15% and 20% doses of AMS caused approximately 80% reduction in germination of P. viticola sporangiospores. The treatments did not show significant effects in reducing both the AUDPC of mildew and polyphenol oxidase enzyme activity. The A. brasiliensis aqueous mycelial suspension showed a fungitoxic effect on the germination of sporangiopores; however, it was not enough to reduce the severity of mildew in the ‘Isabel Precoce’ grapevines, even when acting on the catalase and peroxidase enzymes. Thus, experiments should be performed to verify the viability of the reproductive structures of the pathogen externalized in the vines when treated with A. brasiliensis AMS.

[Use of the Montreal Cognitive Assessment (MoCA) in Latin America: a systematic review]

AIM

To analyze the frequency of use of the Montreal Cognitive Assessment (MoCA) as a cognitive screening instrument, cross-cultural adaptation, the existence of normative data and clinical validation studies in Latin America Hispanic countries.

SUBJECTS AND METHODS

The Medline, PsycINFO, Web of Science, Scopus and Scielo databases were consulted between April and June 2017 according to the PRISMA methodology. We included all studies referencing the MoCA as an instrument to evaluate cognitive deterioration conducted in Latin America and that included normative and psychometric data, as well as its clinical validation.

RESULTS

Of the 80 studies identified, 19 met the inclusion criteria. Most of the studies mentioned the use of the Spanish version of the MoCA and reported a statistically significant effect of gender, age and, most of all, education on the performance of this test. Only five studies presented with a detailed analysis of the psychometric characteristics of the test, and in most articles cut-off scores for the diagnosis of cognitive impairment were the same as the original study.

CONCLUSIONS

The small number of articles identified may reflect a late start of the use of MoCA in Latin America. A tendency towards the use of this test without making a cross-cultural adaptation and the use of international norms was observed in this region. The present systematic review demonstrates the need for future research tackling the development of a linguistically adapted version of the MoCA to Latin America and the study of its psychometric properties, with the aim of improving cognitive assessment.

Acute coronary syndrome remodels the antiplatelet aggregation properties of HDL particle subclasses

Essentials HDL subclasses were studied in acute coronary syndrome (ACS). HDL2 from ACS patients have better antiplatelet potency than HDL from non ACS subjects. ACS remodels the antiplatelet properties of HDL subclasses. Oxidized polyunsaturated fatty acids content of HDL is modified by ACS.

SUMMARY

Background Although HDLs have antithrombotic effects by reducing platelet activation, the relationship between HDL levels and the risk of acute coronary syndrome (ACS) is unclear, as HDL particles are heterogeneous in composition and biological properties. Objective To characterize the effects of HDL2 and HDL3 subclasses from ACS patients and non-coronary artery disease (CAD) subjects on platelet activation. Methods We measured platelet aggregation and ex vivo thrombus formation, analyzed signaling pathways by flow cytometry, and performed a targeted lipidomics analysis on HDL subclasses. Results Analysis of human platelet aggregation in suspension, adhesion on von Willebrand factor and thrombus formation on collagen under arterial shear demonstrated that HDL2 from ACS patients had higher antiplatelet potency than HDL3 from ACS patients and HDL from non-CAD subjects. HDL binding to scavenger receptor class B type I was essential for this effect. A lipidomics analysis revealed that HDL2 from ACS patients had more oxidized polyunsaturated fatty acids (PUFAs). An inverse correlation between the concentrations of 9-hydroxyoctadecadienoic acid (9-HODE), 13-hydroxyoctadecadienoic acid (13-HODE), the eicosapentaenoic acid metabolite 18-hydroxyeicosapentaenoic acid (18-HEPE) and hydroxyeicosatetraenoic acid isomers in HDL2 and platelet aggregation was observed. This relationship was further demonstrated by the direct inhibitory effects of 18-HEPE, 9-HODE, 13-HODE, 17-hydroxydocosahexaenoic acid and 14-hydroxydocosahexaenoic acid on collagen-related peptide-induced platelet aggregation, indicating that oxidized PUFAs contribute to the antithrombotic effect of ACS HDL2. Conclusions Our data shed new light on the antiplatelet effects of HDL subclasses, and suggest physiological adaptation through the modulation of HDL properties in ACS patients that may limit their platelet-dependent thrombotic risk.

Respiratory Syncytial Virus Genotypes, Host Immune Profiles, and Disease Severity in Young Children Hospitalized With Bronchiolitis

Background

Data on how respiratory syncytial virus (RSV) genotypes influence disease severity and host immune responses is limited. Here, we characterized the genetic variability of RSV during 5 seasons, and evaluated the role of RSV subtypes, genotypes, and viral loads in disease severity and host transcriptional profiles.

Methods

A prospective, observational study was carried out, including a convenience sample of healthy infants hospitalized with RSV bronchiolitis. Nasopharyngeal samples for viral load quantitation, typing, and genotyping, and blood samples for transcriptome analyses were obtained within 24 hours of hospitalization. Multivariate models were constructed to identify virologic and clinical variables predictive of clinical outcomes.

Results

We enrolled 253 infants (median age 2.1 [25%-75% interquartile range] months). RSV A infections predominated over RSV B and showed greater genotype variability. RSV A/GA2, A/GA5, and RSV B/BA were the most common genotypes identified. Compared to GA2 or BA, infants with GA5 infections had higher viral loads. GA5 infections were associated with longer hospital stay, and with less activation of interferon and increased overexpression of neutrophil genes.

Conclusions

RSV A infections were more frequent than RSV B, and displayed greater variability. GA5 infections were associated with enhanced disease severity and distinct host immune responses.

Plant-plant competition outcomes are modulated by plant effects on the soil bacterial community

Competition is a key process that determines plant community structure and dynamics, often mediated by nutrients and water availability. However, the role of soil microorganisms on plant competition, and the links between above- and belowground processes, are not well understood. Here we show that the effects of interspecific plant competition on plant performance are mediated by feedbacks between plants and soil bacterial communities. Each plant species selects a singular community of soil microorganisms in its rhizosphere with a specific species composition, abundance and activity. When two plant species interact, the resulting soil bacterial community matches that of the most competitive plant species, suggesting strong competitive interactions between soil bacterial communities as well. We propose a novel mechanism by which changes in belowground bacterial communities promoted by the most competitive plant species influence plant performance and competition outcome. These findings emphasise the strong links between plant and soil communities, paving the way to a better understanding of plant community dynamics and the effects of soil bacterial communities on ecosystem functioning and services.

[Massive pulmonary embolism. When medical treatment is not enough]

Emergency bedside veno-arterious ECMO implantation can be the only saving gesture in the suspicion of acute massive pulmonary embolism leading to haemodynamic failure, even before CT-scan imaging. Once the massive pulmonary embolism is confirmed it is possible to undergo surgical or percutaneous pulmonary thrombectomy, when thrombolytic therapy is contraindicated.

Dose calculation in computerized tomography

The purpose of this work is to develop an automatic methodology to obtain the dose received by a patient, (classified by organs), after being subjected to ionizing radiation because of CT images acquisition. The methodology starts from CT images, these images are automatically segmented and voxelized taking into account the CT numbers in order to obtain a 3D model used in Monte Carlo Simulations to calculate the dose inside the patient.Monte Carlo codes used in this work are MCNP.6.1.1, (whose results will be taken as a reference values) and MC-GPU, which appears to be a good candidate to be implemented in the methodology since his GPU parallelization offers a high speed calculation. Results show good agreement between simulated values obtained by MC-GPU and MCNP6.1.1.

The Effect of 13-Valent Pneumococcal Conjugate Vaccine on the Serotype Distribution and Antibiotic Resistance Profiles in Children With Invasive Pneumococcal Disease

BACKGROUND

Invasive pneumococcal disease (IPD) continues to be a significant burden in children despite the implementation of two generations of conjugate vaccines. Serotype replacement by nonvaccine serotypes is reported in multiple areas around the world. This study is a continuation of previous studies and describes the incidence, serotype distribution, and antibiotic resistance pattern of Streptococcus pneumoniae serotypes causing IPD at Children's Medical Center Dallas after introduction of 13-valent pneumococcal conjugate vaccine (PCV13).

METHODS

Streptococcus pneumoniae isolates from normally sterile sites were collected from January 1, 1999 to June 30, 2014. Demographic and clinical information was extracted for analysis. Incidence of IPD was calculated using inpatient and emergency center admissions to Children's Medical Center of Dallas as the denominator. Isolates were serotyped and penicillin/cefotaxime susceptibilities were determined. Selected nontypeable isolates were further characterized by multilocus sequence typing. A χ2 test and the Cochran-Armitage Trend Test for trend analysis were used to evaluate change in serotype and antibiotic susceptibility patterns over time.

RESULTS

Comparison of the different study periods showed a significant reduction in the incidence of IPD in PCV13 era compared with prevaccine era and PCV7 era (P < .05). Children younger than 24 months showed the largest reduction of disease incidence. More than 40% of patients with IPD had a documented comorbidity. Cases of pneumonia continued to decrease in the PCV13 era (P < .002). The most common non-PCV13 serotypes after vaccine introduction were as follows: 23B, 6C, 23A, 9N/L, and 12. Penicillin resistance by meningitis breakpoint decreased significantly in the PCV13 era.

CONCLUSIONS

After introduction of PCV13 in Dallas, incidence of IPD caused by strains contained in the vaccine and penicillin resistance continued to decrease. Serotype replacement phenomena and persistence of PCV7 serotypes were documented. Patients with comorbidities represented a large percentage of patients with IPD. Concerns for geographic variation in serotype replacement phenomena arise from the present study.

Differences in biological traits composition of benthic assemblages between unimpacted habitats

There is an implicit requirement under contemporary policy drivers to understand the characteristics of benthic communities under anthropogenically-unimpacted scenarios. We used a trait-based approach on a large dataset from across the European shelf to determine how functional characteristics of unimpacted benthic assemblages vary between different sedimentary habitats. Assemblages in deep, muddy environments unaffected by anthropogenic disturbance show increased proportions of downward conveyors and surface deposit-feeders, while burrowing, diffusive mixing, scavenging and predation traits assume greater numerical proportions in shallower habitats. Deep, coarser sediments are numerically more dominated by sessile, upward conveyors and suspension feeders. In contrast, unimpacted assemblages of coarse sediments in shallower regions are proportionally dominated by the diffusive mixers, burrowers, scavengers and predators. Finally, assemblages of gravelly sediments exhibit a relatively greater numerical dominance of non-bioturbators and asexual reproducers. These findings may be used to form the basis of ranking habitats along a functional sensitivity gradient.