Strains In Children Research Articles

Left Ventricular Layer-Specific Myocardial Strains in Children with Recovered Primary Dilated Cardiomyopathy: What Lies Beneath the Iceberg?

We aimed to detect residual cardiac dysfunction-if any-in children with recovered primary dilated cardiomyopathy (DCM) by using the left ventricular (LV) layer-specific myocardial strains. Fifty children with recovered primary DCM both clinically and echocardiographically were included as the patient group. Fifty healthy children of matched age and sex served as the control group. Echocardiographic evaluation was performed for all included children in the form of conventional echocardiography, tissue Doppler imaging (TDI), two-dimensional speckle tracking echocardiography (2D-STE), and LV layer-specific myocardial strain. Both LV systolic and diastolic functions measured by conventional echocardiography were similar in children with recovered DCM and the control group. There was a significant reduction in LV systolic and diastolic functions measured by TDI in the patient group. Moreover, there was a significant reduction of LV global longitudinal systolic strain (GLSS) by 2D-STE in children with recovered DCM. Interestingly, there was a significant reduction of LV layer-specific myocardial strain from endocardium to epicardium in children with recovered DCM compared to the healthy control. There was a significant positive correlation between different layer-specific myocardial strains and LV GLSS, LV ejection fraction, and LV peak systolic velocity. Left ventricular layer-specific myocardial strain can be a promising tool for early identifications of LV dysfunction in children with DCM. Subtle cardiac dysfunction is present in patients with recovered DCM, so long-term follow-up is recommended in these patients.

Phylogenetic variability of Human Metapneumovirus in patients with acute respiratory infections in Cameroon, 2011–2014

BackgroundIdentified in 2001, Human Metapneumovirus (HMPV) is a Pneumovirus associated with acute lower and upper respiratory infections in all age groups and especially in newborns, elderly and immunocompromised subjects. Data are still limited in sub-Saharan African countries genetic characterization of this respiratory virus. This study reports the genetic variability of HMPV strains in Cameroonian children for 3 consecutive epidemic seasons (September 2011–October 2014). MethodsA prospective surveillance was conducted to identify inpatient and outpatient children less than 15 years with respiratory symptoms ≤5 days. The nasopharyngeal samples were tested for HMPV using a multiplex polymerase chain reaction. Viral distribution and demographic data were analyzed statistically. Positive samples for HMPV were amplified by semi-nested polymerize chain reaction and then partially sequenced at the G gene. Phylogenetic analyzes were performed on the partial nucleotide and protein sequences of the G gene. ResultsFrom September 2011 to October 2014, 822 children under 15 years were enrolled in the study. HMPV was identified in each of 3.9% (32/822) of children. HMPV were detected throughout the year. HMPV-A (73.3%; 11/15) was predominant compared to HMPV-B (26.7; 4/15). Cameroonian HMPV strains are grouped among the members of genotype A2b (for HMPV-A), B1 and B2 (for HMPV-B). ConclusionThis study suggests that about 4% of ARI recorded in children in Cameroon are caused by HMPV. The present study is also the first report on the genetic variability of the G gene of HMPV strains in the region. Although this work partially fills gaps for some information, additional studies are required to clarify the molecular epidemiology and evolutionary pattern of HMPV in sub-Saharan Africa in general and more particularly in Cameroon.

Clinical characteristics, molecular epidemiology and antimicrobial susceptibility of pertussis among children in southern China.

Increasing numbers of pertussis cases have been reported in recent years. The reported cases from Shenzhen Children's Hospital were close to one tenth of all cases in China. The epidemiology of antigenic genotype and antibiotic resistance of circulating strains in children have been unknown in Shenzhen, southern China. The aim of this study was to describe the clinical features and explore the genotypes and antimicrobial susceptibility of circulating Bordetella pertussis among children in Shenzhen. Data of hospitalized children with pertussis in Shenzhen Children's Hospital from August 2015 to April 2017 were collected. The genetic variability of isolates was investigated and Etest was performed for phenotypic susceptibility to erythromycin, azithromycin, clarithromycin, clindamycin, and trimethoprim/sulfamethoxazole. 469 children with pertussis confirmed by real-time quantitative polymerase chain reaction were hospitalized and strains were isolated from 105 patients. White blood cell count ≥ 20 × 109/L and lymphocyte proportion ≥ 60% were observed in 39.29% of infants younger than 3months. The two predominant profiles of virulence-associated allelic genes were ptxA1/ptxC1/ptxP1/prn1 (48.6%) and ptxA1/ptxC2/ptxP3/prn2 (44.8%). Among the isolates, 48.6% (51/105) were found resistant to macrolides. These findings indicate that leukocytosis is not a sensitive indicator of pertussis. Isolates with the gene profile ptxP3/prn2 were highly circulating in Shenzhen and less resistant to macrolides, different from patterns observed in other parts of China.

Impairment of left and right ventricular longitudinal strain in asymptomatic children with type 1 diabetes

AimThe relationship between type 1 diabetes (T1DM) and cardiac function in children is not well established. The purpose of this study was to investigate whether children and adolescents with T1DM present early asymptomatic abnormalities of left ventricular (LV) and right ventricular (RV) function. In addition, we evaluated the relationship of any such abnormalities with glycemic control and diabetes duration. MethodsThis was a prospective study. Standard echocardiography, tissue Doppler imaging, and two-dimensional strain analysis were performed prospectively in 52 children with T1DM. The results were compared with those from 52 healthy children matched for age and sex. ResultsThere were no significant differences between the two groups in LV ejection fraction or RV systolic function. There was a difference between the two study groups in transtricuspid flow: the E-wave and A-wave velocities were significantly higher in the diabetic group. Left ventricular global longitudinal strain (LV GLS) was significantly lower in children with T1DM (−20.01 ± 1.86% vs. −22.99 ± 0.98%, respectively; P < .001), as was RV free-wall longitudinal strain (RV FWLS) (−29.13 ± 1.85% vs. −30.22 ± 1.53%, respectively; P = .002). LV GLS was correlated with diabetes duration (r = 0.444, P < .001) and glycated hemoglobin (HbA1c) (r = 0.683, P < .001); however, no correlation was found between RV FWLS and HbA1c or diabetes duration. ConclusionsOur findings suggest that LV GLS and RV FWLS are impaired in children with T1DM and that the decrease in LV GLS is correlated with diabetes duration and HbA1c levels.

Efficacy of Miramistin in the correction of the oropharynx microbiocenosis in sickly children

There are presented data of the analysis of the composition of the oropharynx microbiota and antimicrobial resistance of opportunistic bacteria isolated in sickly children to determine the effectiveness of the preparation Miramistin. There was executed a bacteriological study of the microflora of the oropharynx in 71 children with respiratory recurrent infections (RIRs). There was determined the resistance of isolated species ofpathogens of respiratory infections to antibiotics of different classes. Children suffering from RIRs were found to have species and and quantitative disorders of the pattern ofpharynx microflora in 90,2% of cases. In cultures from oropharyngeal mucosa there were isolated 15 types of potentially pathogenic bacteria, among them there were dominated: S. aureus (31%), Haemophilus influenzae (11,3%),) Strept. pyogenes (11,3%) and Strept. pneumoniae (8,4%). All of the isolated in sickly children strains of S. aureus and Strept. pyogenes (including strains resistant to antibiotics and bacteriophages) were susceptible to Miramistin. There was proved high efficiency and safety of Miramistin in the complex therapy of various forms of inflammatory diseases oa upper respiratory tract: angina, chronic tonsillitis, pharyngitis and nasopharyngitis in children. It is recommended to always include Miramistin in the complex treatment of infectious and inflammatory diseases of the oropharynx.

Immunogenicity and safety of the new MMR vaccine containing measles AIK-C, rubella Takahashi, and mumps RIT4385 strains in Japanese children: a randomized phase I/II clinical trial

ABSTRACTDomestic measles, mumps, and rubella combined (MMR) vaccines were discontinued in 1993 in Japan because of the unexpected high incidence of aseptic meningitis. The introduction of an effective MMR vaccine with lower reactogenicity has been expected. A new MMR vaccine (JVC-001) was developed, using mumps RIT4385 strain in combination with Japanese measles AIK-C strain and rubella Takahashi strain (MR) vaccine. An open-label, randomized, phase I/II clinical study was conducted in 100 healthy Japanese children equally randomized to a JVC-001 group and an MR with monovalent mumps vaccine (Hoshino strain) group. Immunogenicity was assessed using a neutralization test (NT) for measles, hemagglutination inhibition (HI) test for rubella, and NT and enzyme-linked immune-sorbent assay (ELISA) for mumps strain with different genotypes (genotype A, B, D and G) on Day 0 and Day 42–56. Solicited and unsolicited adverse events (AEs) were recorded. Seroconversion rates of measles and rubella were both 100%. JVC-001 induced higher immunogenicity against mumps virus genotype G with seroconversion rate of 77.1% (95% confidence interval [CI]: 62.7–88.0%) compared to 65.3% (95% CI: 50.4–78.3%) in the control group. Geometric mean titer (GMT) was 12.5 (95% CI: 8.6–18.3) in the JVC-001 group and 7.1 (95% CI: 5.0–10.1) in the control group. JVC-001 also induced good immunogenicity against other genotypes (A, B and D). There was no apparent difference in the incidence of AEs between JVC-001 and the control groups. JVC-001 is safe and induces effective immunogenicity against measles, mumps, and rubella compared with the currently marketed vaccines in Japan.

Molecular epidemiology and genetic diversity of human parechoviruses in children hospitalized with acute diarrhea in Thailand during 2011-2016

Little is known about human parechovirus (HPeV) infection in Thailand. The genotype distribution of HPeV strains in children admitted to hospitals with acute gastroenteritis was investigated using polymerase chain reaction (PCR) and nucleotide sequencing of the VP1 region as the detection and genotype identification methods, respectively. Of a total of 2,002 stool samples, 49 (2.4%) were positive for HPeV. Of these, HPeV-1 was the most predominant genotype (40.8%), followed by HPeV-3 (16.3%) and HPeV-14 (16.3%), while HPeV-5, -6, -2, -4, and -8 strains were less frequently detected, at 10.2%, 8.2%, 2%, 2%, and 2%, respectively. HPeV infections were detected throughout the year with the biannual peaks of infection in the rainy (Jun-Jul-Aug) and winter (Nov-Dec-Jan) months in Thailand. Based on VP1 amino acid sequence alignment, the arginyl-glycyl-aspartic acid (RGD) motif was found in HPeV-1, -2, -4, and -6 strains. Additionally, an amino acid insertion at the N-terminus of VP1 was observed in HPeV-4 and HPeV-5 strains. Phylogenetic analysis revealed that small clades of HPeV-1 and HPeV-3 strains emerged in 2016 and 2015, respectively, and dominated in the year of their emergence. The HPeV strains detected in Thailand in this study were most closely related to reference strains from Asia and Europe. The evolutionary rate of HPeV strains was 2.87 × 10-4 (95% highest posterior density (HPD) 0.10-6.14 × 10-4) substitutions/site/year. These findings provide information about the genetic diversity and evolutionary dynamics of HPeV genotypes circulating in pediatric patients with acute gastroenteritis in Thailand.

Left Ventricular Regional Function in Children with Beta Thalassemia with No Cardiac Manifestations (Four-Dimensional Echocardiographic Study).

Early detection of myocardial dysfunction is essential for the management of patients with thalassemia. Four-dimensional echocardiography imaging technique may be useful for detecting subclinical cardiovascular disease. To evaluate the 4-dimensional echocardiographic strain in children with beta thalassemia major with no cardiac manifestation and correlate it with other echocardiographic parameters. This is a prospective cross-sectional cohort Study included 200 children, 1-18years-old. They were divided into: One hundred children with p-Thalassemia major with no clinical cardiac manifestations and 100 healthy children as a control group. They were subjected to the following investigations: Complete blood count, serum ferritin and Four-dimensional echocardiographic strains (Longitudinal, Circumferential, Radial and Area strains). There was no significant difference between the two groups as regard mitral annulus systolic velocity (S wave), E/A ratio and iso-volumic acceleration, but there was a significant difference as regard to ejection fraction, left ventricle mass, sphericity index and myocardial performance index. The mean values of Left Ventricular Strains (Longitudinal, Circumferential, Radial and Area strains) were significantly lower in patients with thalassemia (- 14.86 ± 12.13, - 8.01 ± 3.829, 33.13 ± 10.61, - 19.45 ± 6.866) than controls (- 19.13 ± 1.502, - 16.32 ± 1.34, 37.28 ± 4.209, - 22.94 ± 3.06) than controls respectively with a positive correlation with 2-Dimensional strain. Strain parameters of the left ventricle obtained by four-dimensional.

Assessment of right ventricular strain in children with repaired tetralogy of Fallot using speckle tracking imaging.

Assessment of right ventricular strain in children with repaired tetralogy of Fallot using speckle tracking imaging.

Transcriptome analysis of beta-lactamase genes in diarrheagenic Escherichia coli

Beta (β)-lactamases are the most important agents that confer drug resistance among gram-negative bacteria. Continuous mutations in β-lactamases make them remarkably diverse. We carried out the transcriptome analysis of 10 β-lactamase genes of Extended-Spectrum β-lactamases (ESBL), Metallo β-lactamases (MBL), and AmpC β-lactamases (ABL) in drug-resistant and sensitive diarrheagenic E. coli (DEC) isolates obtained from children up to 5 years of age. Out of the 10 β-lactamase genes, four belonged to ESBL (TEM, SHV, CTX, and OXA); three to MBL (NDM-1, IMP, and VIM); and three to ABL (ACT, DHA and CMY) class of genes. The different categories of DEC were estimated for β-lactamases production using a set of conventional phenotypic tests, followed by detection of their messenger RNA (mRNA) expression. The study revealed a direct correlation between mRNA expression of these genes and the presence of antibiotic resistance; also corroborated by mutation analysis of the AmpC promoter region. All the 10 β-lactamase genes showed a significant increase in their expression levels in resistant isolates, compared to those of the sensitive isolates, indicating their possible role in the disease pathogenesis. Increase in mRNA expression of β-lactamase genes, and thereby virulence, may be due to multifactorial parameters causing phenotypic as well as genotypic changes. Our study highlights the necessity of instantaneous detection of β-lactamase gene expression to curb the overwhelming threat posed by emergence of drug resistance amongst the commensal E. coli strains in children from developing countries for larger public health interest.

Normal Values for Left Ventricular Strain and Synchrony in Children Based on Speckle Tracking Echocardiography

Strain and synchrony are associated with clinical outcomes in children with heart diseases. Robust normative data for these values, measured by 2-dimensional speckle tracking echocardiography (2DSTE), are limited. Therefore, we aimed to derive normal ranges and z-scores of 2DSTE strain and synchrony parameters in children. Subjects were <21 years old with structurally and functionally normal hearts. High frame-rate 2-dimensional echocardiographic images were retrospectively analyzed to measure longitudinal (LS) and circumferential (CS) strain and synchrony; views used were apical 4, 2, and 3-chamber (AP 4, 2, 3) and mid-papillary short-axis (SAX-M). Synchrony measures included standard deviation of time to peak strain, maximal wall delay, and cross-correlation mean segmental delay; these were calculated without and with heart rate (HR) correction (divided by √RR). Z-score equations were created for AP4 and SAX-M strain components. n = 312 subjects (40% female) were included (age 3 days to 20.5 years). Mean strain values (%) were: AP4 -24.4 ± 3.2, AP2 -24.2 ± 3.3, AP3 -24.6 ± 3.4, SAX-M -25.8 ± 3.4. Significant differences between ages were present for all strain components (AP4 p < 0.001; AP2 p = 0.003; AP3 p = 0.014; SAX-M p = 0.01). LS components decreased with increasing age and body surface area (p < 0.001 for all); CS did not. Longitudinal, but not circumferential, synchrony parameters decreased with age; however, these were nonsignificant after HR correction. In conclusion, normal pediatric 2DSTE strain and synchrony parameters and z-scores are reported to provide a foundation for incorporation into clinical practice. LS decline with age whereas CS does not. Age-related decreases in LS synchrony were mostly nonsignificant when corrected for HR.

Speckle-Tracking Echocardiography in Children With Duchenne Muscular Dystrophy: A Prospective Multicenter Controlled Cross-Sectional Study

Prognosis of Duchenne muscular dystrophy (DMD) is related to cardiac dysfunction. Speckle-tracking echocardiographic (STE) imaging is emerging as a noninvasive functional biomarker to consider in the early detection of DMD-related cardiomyopathy. However, STE analysis has not been assessed in a prospectively controlled study, especially in presymptomatic children with DMD, and no study has used STE analysis in all three displacements (longitudinal, radial, and circumferential) and for both ventricles. This prospective controlled study enrolled 108 boys, 36 of whom had DMD (mean age, 11±3.8years) and 72 of whom were age-matched control subjects in a 1:2 case-control design. Conventional echocardiographic variables were collected for the left and right ventricles. STE analyses were performed in the longitudinal, radial, and circumferential displacements for the left ventricle and in the free wall longitudinal displacement for the right ventricle. The effect of age on the evolution of two-dimensional strain in children with DMD was studied by adding an interaction term, DMD×age, in the models. Conventional echocardiographic measures were normal in both groups. Left ventricular (LV) ejection fraction ranged from 45% to 76% (mean, 63±6%) in the DMD group and from 55% to 76% (mean, 64±5%) in the control group. Global LV strain mean measures were significantly worse in the DMD group for the longitudinal (-16.8±3.9% vs -20.6±2.6%, P<.0001), radial (22.7±11.3% vs 31.7±14%, P=.002), and circumferential (-16.5±3.8% vs -20.3±3.1%, P<.0001) displacements. The decrease of global LV longitudinal strain with age in children with DMD was 0.34% per year more marked than that in control subjects. The LV inferolateral and anterolateral segments were specifically impaired, especially in the basal area. Right ventricular function evaluated using conventional echocardiography and STE analysis was normal and not different between children with DMD and control subjects. The existence of altered LV strain despite normal LV function in children with DMD represents an important perspective for future pediatric drug trials in DMD-related cardiomyopathy prevention.

Invasive pneumococcal disease in hospitalised children from Lima, Peru before and after introduction of the 7-valent conjugated vaccine.

The objective of this study was to determine the serotype distribution and antibiotic resistance of invasive pneumococcal disease (IPD) strains in children from Lima, Peru, before and after the introduction of the 7-valent pneumococcal conjugate vaccine (PCV7), which was introduced in the national immunisation program on 2009. We conducted a prospective, multicentre, passive surveillance IPD study during 2006-2008 and 2009-2011, before and right after the introduction of PCV7 in Peru. The study was performed in 11 hospitals and five private laboratories in Lima, Peru, in patients &lt;18 years old, with sterile site cultures yielding Streptococcus pneumoniae. In total 159 S. pneumoniae isolates were recovered. There was a decrease in the incidence of IPD in children &lt;2 years old after the introduction of PCV7 (18.4/100 000 vs. 5.1/100 000, P = 0.004). Meningitis cases decreased significantly in the second period (P = 0.036) as well as the overall case fatality rate (P = 0.025), including a decreased case fatality rate of pneumonia (16.3% to 0%, P = 0.04). PCV7 serotypes showed a downward trend. Vaccine-preventable serotypes caused 78.9% of IPD cases, mainly 14, 6B, 5, 19F and 23F. A non-significant increase in erythromycin resistance was reported. Our findings suggest that the introduction of PCV7 led to a significant decrease of IPD in children under 2 years old and in the overall case fatality rate.

Secretory breast carcinoma: A report of two cases

Secretory breast carcinoma was first described by McDivitt and Stewart in 1966, who reported seven cases of this tumoural strain in children and therefore named it “juvenile carcinoma”. However, a couple of decades later, Tavassoli and Norris reported a series of 19 cases and found that most occurred in adults, and therefore they proposed changing its name to “secretory carcinoma.” Since then, approximately 100 cases have been reported in the world literature. We present two cases treated with total mastectomy and sentinel node biopsy with excellent outcome. To our knowledge, only a few cases have been reported in Latin American patients.

Brain tissue strain and balance impairments in children following a concussion: An exploratory study

Background Balance impairments present in approximately 30% of concussion cases. Biomechanical reconstructions model the degree and location of brain tissue strain associated with injury. The objective was to examine the relationship between the magnitude and location of brain tissue strain and balance impairment following a concussion. Methods Children one month post-concussion (n = 33) and non-injured children (n = 33) completed two balance conditions while standing on a Wii Balance Board that recorded the centre of pressure during (i) double-leg stance with eyes closed (EC) and (ii) dual-task (DT) combining double-leg stance while completing a cognitive task. Injury reconstructions were performed for 10 of the concussed participants. A 5th percentile Hybrid III headform was used to obtain linear and rotational acceleration time-curves of the head impact. These data were input in the University College Dublin Brain Trauma Model (UCDBTM) to calculate maximum principal strains and cumulative strain damage values at 10% (CSDM-10) and 20% (CSDM-20) for different brain regions. Correlations between balance and reconstruction variables were calculated. Results Out of the 10 reconstructed cases, six participants had impaired balance on the EC condition, six had impaired balance on the DT condition and four had impaired balance on both the EC and DT conditions. For maximum principal strain values, correlations with balance variables ranged from −0.0190 to 0.394 for the DT condition and from −0.225 and 0.152 for the EC condition. For CSDM-10 values, correlations with balance variables ranged from 0.280 to 0.386 for the DT condition and from −0.103 to 0.252 for the EC condition. For CSDM-20 values, correlations with balance variables ranged from 0.0629 to 0.289 for the DT condition and from −0.353 to −0.155 for the EC condition. Conclusions Although a subset of the concussed participants continued to show balance impairments, no association was established between the presence of balance impairment and the magnitude and/or location of brain tissue strain. Maintaining balance is a complex process integrated into multiple subcortical regions, white matter tracts and cranial nerves, which were not represented in the brain model, and as a result the UCDBTM may not be sensitive to damage in these areas.

Detection of eye strain through blink rate and sclera area using raspberry-pi

ABSTRACTIn this paper, a unique approach is proposed to determine eye strain in children caused due to the prolonged exposure to LCD and PDP screens. Blink rate and area of eye sclera are the two efficient metrics relied upon to determine eye strain. Initially, blink rate is computed by monitoring state transitions from open to closed eyes. To segment the sclera region of the eye Otsu’s thresholding and colour tracking, were implemented. These approaches had limitations due to illumination and skin tone. To overcome this, Modified Otsu using Colour Tracking is proposed in this paper. The occurrence of eye strain is determined by comparing the values of the metrics derived in real time with a threshold. The proposed algorithm detects eye strain with an accuracy of 83%. After detection of fatigue an alert message is sent to caretakers.

Impact of existing vaccines in reducing antibiotic resistance: Primary and secondary effects

Vaccines impact antibiotic-resistant infections in two ways: through a direct reduction in the organisms and strains carrying resistant genes that are specifically targeted by the vaccine and also via a secondary effect through a reduction in febrile illnesses that often lead to the use of antibiotics. We review here the impact of pneumococcal conjugate vaccines (PCVs) on the prevalence of antibiotic-resistant disease and antibiotic usage as an example of the direct effect of vaccines on antibiotic resistance and the impact of influenza vaccination on antibiotic usage as an example of a secondary effect. A prelicensure study of a PCV in Africa demonstrated 67% fewer penicillin-resistant invasive disease episodes in the PCV group compared with controls. Similar studies in the United States and Europe demonstrated reductions in antibiotic use consistent with the vaccines’ impact on the risk of otitis media infections in children. Postlicensure reductions in the circulation of antibiotic-resistant strains targeted by the vaccines have been dramatic, with virtual elimination of these strains in children following vaccine introduction. In terms of a secondary effect, following influenza vaccination reductions of 13–50% have been observed in the use of antibiotics by individuals receiving influenza vaccine compared with controls. With the demonstrated effectiveness of vaccination programs in impacting the risk of antibiotic-resistant infections and the increasing threat to public health that these infections represent, more attention needs to be given to development and utilization of vaccines to address antibiotic resistance.

Antimicrobial resistance changes of carbapenem-resistant Enterobacteriaceae strains isolated from children

Objective: To investigate the prevalence and resistance changes of carbapenem-resistant Enterobacteriaceae (CRE) strains isolated from children patients of Chinese Bacterial Resistance Surveillance Network (CHINET) from 2005 to 2017. Methods: Antimicrobial susceptibility testing was carried out by disk diffusion method (KB method) and automated systems. Results were analyzed according to the Clinical and Laboratory Standards Institute (CLSI) 2017 edition standards. Results: Among the 4 481 CRE clinical strains, the overall prevalence of CRE in children was 6.4%, including 8.8% in neonatal period, 7.3% in infancy, 3.8% in early childhood, 4.0% in preschool, 4.7% at school age and 7.4% of puberty. The CRE prevalence of citrobacter spp. remained stable in 2005-2017, whereas other bacteria showed an upward trend, which was higher than that of the adult group (P<0.01). Among the 4 481 CRE strains, there were 2 905 strains of Klebsiella spp. (64.8%), 813 strains of Escherichia coli (18.1%), 549 strains of Enterobacter spp.(12.3%), and 65 strains of Citrobacter spp.(1.5%). Among the 4 481 CRE strains, 20.7%, 13.3%, and 11.8% were from the intensive care unit (ICU), neonatal department and internal medicine wards, respectively. Specimens were distributed as respiratory (42.8%), urine (26.3%), and blood (14.9%). The results of antimicrobial susceptibility testing exhibited that the CRE strains were highly resistant to most commonly used antimicrobial agents in clinical practice, such as imipenem, meropenem and ertapenem, as well as penicillins and cephalosporins, etc. Conclusion: The prevalence of CRE strains in children is increasing year by year, and their antimicrobial resistance to common antibacterial agents in clinical practice is extremely serious, to which serious attention needs to be paid. According to the results of antimicrobial susceptibility testings, the antibacterial agents should be rationally selected to effectively control the spread of CRE.

Right ventricular function in infants with bronchopulmonary dysplasia and pulmonary hypertension: a pilot study.

Premature birth and bronchopulmonary dysplasia (BPD) are risk factors for the development of echocardiographic signs of pulmonary hypertension (PH) and are associated with changes in cardiac structure and function. It is unclear whether this association persists beyond early infancy. The aims of this study are to prospectively investigate the prevalence of PH in children with severe BPD and to investigate the effect of BPD and PH on myocardial structure and function at six months corrected age. Preterm infants (gestational age ≤ 32 weeks) with severe BPD were included. Echocardiography was used to define PH and to measure speckle tracking derived longitudinal and circumferential strain of the left ventricle (LV) and right ventricle (RV). Sixty-nine infants with a median (interquartile range [IQR]) gestational age of 25.6 (24.9–26.4) weeks and a median birthweight of 770 (645–945) gram were included. Eight (12%) infants had signs of PH at six months corrected age. RV fractional area change was lower in infants with severe BPD and PH at six months compared to infants without PH (35% ± 9% vs. 43% ± 9%, P = 0.03). RV mean longitudinal systolic strain was lower in infants with severe BPD and PH compared to infants without PH (17.6% [−19.5%/−16.1%] vs. −20.9% [−25.9%/−17.9%], P = 0.04). RV size and LV longitudinal and circumferential strain in children with BPD with or without PH were similar. Signs of PH were found in 12% of infants with severe BPD at six months corrected age and the presence of PH is associated with reduced RV systolic function.

1973. A Meta-Analysis of the Effectiveness of LAIV4 and IIV against Influenza A/H3N2 Strains in Children 2–18 Years of Age During the 2016–2017 Season

BackgroundThe effectiveness of the quadrivalent live attenuated influenza vaccine (LAIV4) and inactivated influenza vaccines (IIV) has been evaluated in recent seasons using a number of different study designs (e.g., randomized controlled studies [RCT], cohort studies and test-negative case–control [TNCC] studies). Effectiveness estimates from these studies have, in general, had very broad confidence intervals reflecting the small numbers of cases reported. We conducted a meta-analysis to more precisely estimate the effectiveness of both vaccine types for the 2016–2017 season.MethodsLAIV4 and IIV efficacy and effectiveness studies conducted over the 2016–2017 influenza season were identified from the published literature and through personal communication with the study investigators. Effectiveness estimates from all available study designs were included in the meta-analysis to maximize use of all available data and because all studies included methods to minimize bias. The analysis provided average estimates of the LAIV4 and IIV efficacy across countries. A sensitivity analysis limited to TNCC studies was also conducted. Only effectiveness results for A/H3N2 strains were combined as circulation of other strains was minimal. The meta-analyses used a random effects model. Heterogeneity testing was performed.ResultsSeven studies conducted in children in the United States, Japan, Finland, Germany, thr UK, and Canada were identified including four TNCC studies, one cohort study and one RCT (Figure 1). Individual effectiveness estimates ranged from 29% to 74% for LAIV4 and from 31% to 56% for IIV. Heterogeneity testing for H3N2 strains was not statistically significant. The consolidated effectiveness estimate across studies for LAIV4 was 44% (95% CI: 24, 58) and for IIV was 45% (95% CI: 29, 58). Estimates for the sensitivity analysis limited to TNCC studies were 61% (95% CI: 40, 74) and 43% (95% CI: 32, 52) for LAIV4 and IIV, respectively. ConclusionDespite variability in estimates across studies, both LAIV4 and IIV showed moderate and comparable effectiveness in children for circulating H3N2 strains during the 2016–2017 influenza season.Disclosures R. Mallory, MedImmune: Employee, Salary. A. Bandell, AstraZeneca: Employee, Salary. C. S. Ambrose, AstraZeneca: Employee, Salary. J. Yu, GSK: Employee, Salary and Stockholder.