Racial and ethnic inequities in the quality of paediatric care in the USA: a review of quantitative evidence

Racial and ethnic inequities in paediatric care have received increased research attention over the past two decades, particularly in the past 5 years, alongside an increased societal focus on racism. In this Series paper, the first in a two-part Series focused on racism and child health in the USA, we summarise evidence on racial and ethnic inequities in the quality of paediatric care. We review studies published between Jan 1, 2017 and July 31, 2022, that are adjusted for or stratified by insurance status to account for group differences in access, and we exclude studies in which differences in access are probably driven by patient preferences or the appropriateness of intervention. Overall, the literature reveals widespread patterns of inequitable treatment across paediatric specialties, including neonatology, primary care, emergency medicine, inpatient and critical care, surgery, developmental disabilities, mental health care, endocrinology, and palliative care. The identified studies indicate that children from minoritised racial and ethnic groups received poorer health-care services relative to non-Hispanic White children, with most studies drawing on data from multiple sites, and accounting for indicators of family socioeconomic position and clinical characteristics (eg, comorbidities or condition severity). The studies discussed a range of potential causes for the observed disparities, including implicit biases and differences in site of care or clinician characteristics. We outline priorities for future research to better understand and address paediatric treatment inequities and implications for practice and policy. Policy changes within and beyond the health-care system, discussed further in the second paper of this Series, are essential to address the root causes of treatment inequities and to promote equitable and excellent health for all children.

Stratification of risk for emergent intracranial abnormalities in children with headaches: a Pediatric Emergency Care Applied Research Network (PECARN) study protocol

INTRODUCTION

Headache is a common chief complaint of children presenting to emergency departments (EDs). Approximately 0.5%-1% will have emergent intracranial abnormalities (EIAs) such as brain tumours or strokes. However, more than one-third undergo emergent neuroimaging in the ED, resulting in a large number of children unnecessarily exposed to radiation. The overuse of neuroimaging in children with headaches in the ED is driven by clinician concern for life-threatening EIAs and lack of clarity regarding which clinical characteristics accurately identify children with EIAs. The study objective is to derive and internally validate a stratification model that accurately identifies the risk of EIA in children with headaches based on clinically sensible and reliable variables.

METHODS AND ANALYSIS

Prospective cohort study of 28 000 children with headaches presenting to any of 18 EDs in the Pediatric Emergency Care Applied Research Network (PECARN). We include children aged 2-17 years with a chief complaint of headache. We exclude children with a clear non-intracranial alternative diagnosis, fever, neuroimaging within previous year, neurological or developmental condition such that patient history or physical examination may be unreliable, Glasgow Coma Scale score<14, intoxication, known pregnancy, history of intracranial surgery, known structural abnormality of the brain, pre-existing condition predisposing to an intracranial abnormality or intracranial hypertension, head injury within 14 days or not speaking English or Spanish. Clinicians complete a standardised history and physical examination of all eligible patients. Primary outcome is the presence of an EIA as determined by neuroimaging or clinical follow-up. We will use binary recursive partitioning and multiple regression analyses to create and internally validate the risk stratification model.

ETHICS AND DISSEMINATION

Ethics approval was obtained for all participating sites from the University of Utah single Institutional Review Board. A waiver of informed consent was granted for collection of ED data. Verbal consent is obtained for follow-up contact. Results will be disseminated through international conferences, peer-reviewed publications, and open-access materials.

Research Priorities for Pediatric Emergency Care to Address Disparities by Race, Ethnicity, and Language

Importance

Health care disparities are well-documented among children based on race, ethnicity, and language for care. An agenda that outlines research priorities for disparities in pediatric emergency care (PEC) is lacking.

Objective

To investigate research priorities for disparities in PEC among medical personnel, researchers, and health care-affiliated community organizations.

Design, Setting, and Participants

In this survey study, a modified Delphi approach was used to investigate research priorities for disparities in PEC. An initial list of research priorities was developed by a group of experienced PEC investigators in 2021. Partners iteratively assessed the list through 2 rounds of electronic surveys using Likert-type responses in late 2021 and early 2022. Priorities were defined as achieving consensus if they received a score of highest priority or priority by at least 60% of respondents. Asynchronous engagement of participants via online web-conferencing platforms and email correspondence with electronic survey administration was used. Partners were individuals and groups involved in PEC. Participants represented interest groups, research and medical personnel organizations, health care partners, and laypersons with roles in community and family hospital advisory councils. Participants were largely from the US, with input from international PEC research networks.

Outcome

Consensus agenda of research priorities to identify and address health care disparities in PEC.

Results

PEC investigators generated an initial list of 27 potential priorities. Surveys were completed by 38 of 47 partners (80.6%) and 30 of 38 partners (81.1%) in rounds 1 and 2, respectively. Among 30 respondents who completed both rounds, there were 7 family or community partners and 23 medical or research partners, including 4 international PEC research networks. A total of 12 research priorities achieved the predetermined consensus threshold: (1) systematic efforts to reduce disparities; (2) race, ethnicity, and language data collection and reporting; (3) recognizing and mitigating clinician implicit bias; (4) mental health disparities; (5) social determinants of health; (6) language and literacy; (7) acute pain-management disparities; (8) quality of care equity metrics; (9) shared decision-making; (10) patient experience; (11) triage and acuity score assignment; and (12) inclusive research participation.

Conclusions and Relevance

These results suggest a research priority agenda that may be used as a guide for investigators, research networks, organizations, and funding agencies to engage in and support high-priority disparities research topics in PEC.

Health disparities in pediatric sleep-disordered breathing

Sleep-disordered breathing reflects a continuum of overnight breathing difficulties, ranging from mild snoring to obstructive sleep apnea syndrome. Sleep-disordered breathing in childhood is associated with significant adverse outcomes in multiple domains of functioning. This review summarizes the evidence of well-described ethnic, racial, and socioeconomic disparities in pediatric sleep-disordered breathing, from its prevalence to its treatment-related outcomes. Research on potential socio-ecological contributors to these disparities is also reviewed. Critical future research directions include the development of interventions that address the modifiable social and environmental determinants of these health disparities.

Effects of a Curriculum Addressing Racism on Pediatric Residents' Racial Biases and Empathy

BACKGROUND

Racism is a longstanding driver of health inequities. Although medical education is a potential solution to address racism in health care, best practices remain unknown.

OBJECTIVE

We sought to evaluate the impact of participation in a curriculum addressing racism on pediatric residents' racial biases and empathy.

METHODS

A pre-post survey study was conducted in 2 urban, university-based, midsized pediatric residency programs between July 2019 and June 2020. The curriculum sessions included Self-Reflection on Implicit Bias, Historical Trauma, and Structural Racism. All sessions were paired with empathy and perspective-taking exercises and were conducted in small groups to facilitate reflective discussion. Wilcoxon signed rank tests were used to assess changes in racial bias and empathy. Linear regression was used to assess the effect of resident characteristics on racial bias and empathy.

RESULTS

Ninety of 111 residents receiving the curriculum completed pre-surveys (81.1%), and among those, 65 completed post-surveys (72.2%). Among participants with baseline pro-White bias, there was a statistically significant shift (0.46 to 0.36, P=.02) toward no preference. Among participants with a baseline pro-Black bias, there was a statistically significant shift (-0.38 to -0.21, P=.02), toward no preference. Among participants with baseline pro-White explicit bias, there was a statistically significant shift (0.54 to 0.30, P<.001) toward no preference. Among all residents, there was a modest but statistically significant decrease in mean empathy (22.95 to 22.42, P=.03).

CONCLUSIONS

Participation in a longitudinal discussion-based curriculum addressing racism modestly reduced pediatric residents' racial preferences with minimal effects on empathy scales.

Estimating biofuel contaminant concentration from 4D ERT with mixing models

We present the results of a lab-scaled feasibility study to assess the performance of electrical resistivity tomography for detection, characterization, and monitoring of fuel grade ethanol releases to the subsurface. Further, we attempt to determine the concentration distribution of the ethanol from the electrical resistivity tomography data using mixing-models. Ethanol is a renewable fuel source as well as an oxygenate fuel additive currently used to replace the known carcinogen methyl tert-butyl ether; however, ethanol is preferentially biodegraded and a cosolvent. When introduced to areas previously impacted by nonethanol-based fuels, it will facilitate the persistence of carcinogenic fuel compounds like benzene and ethylbenzene, as well as remobilize them to the ground water. These compounds would otherwise be retained in the soil column undergoing active or passive remediation processes such as soil vapor extraction or natural attenuation. Here, we introduce ethanol to a saturated Ottawa sand in a tank instrumented for four-dimensional geoelectrical measurements. Forward model results suggest pure phase ethanol released into a water saturated silica sand should present a detectable target for electrical resistivity tomography relative to a saturated silica sand only. We observe the introduction of ethanol to the closed hydraulic system and subsequent migration over the duration of the experiment. One-dimensional and three-dimensional temporal data are assessed for the detection, characterization, and monitoring of the ethanol release. Results suggest one-dimensional geoelectrical measurements may be useful for monitoring a release, while three-dimensional geoelectrical field imaging would be useful to characterize, monitor, and design effective remediation approaches for an ethanol release, assuming field conditions do not preclude the application of geoelectrical methods. We then attempt to use predictive mixing models to calculate the distribution of ethanol concentration within the measurement domain. For this study we examine four different models: a nested parallel mixing model, a nested cubic mixing model, the complex refractive index model (CRIM), and the Lichtenecker-Rother (L-R) model. The L-R model, modified to include an electrical formation factor geometry term, provided the best agreement with expected EtOH concentrations.

Antiracism, Black Lives Matter, and Critical Race Theory: The ABCs of Promoting Racial Equity in Pediatric Practice

Police shootings of unarmed Black men, women, and children at the intersection of disparities in the setting of the coronavirus disease 2019 pandemic have resulted in a long overdue national awakening regarding race and racism in society. This article defines some of the key terms, providing a foundation to help promote equity in pediatric practice. Although no single article can result in full competency regarding such complex issues, it is meant to provide a foundation for pediatricians on a journey to deepen their knowledge and understanding toward a path to action. [Pediatr Ann. 2022;51(3):e95-e106.].

Racial/Ethnic Differences in Pediatric Emergency Department Wait Times

OBJECTIVES

Wait time for emergency care is a quality measure that affects clinical outcomes and patient satisfaction. It is unknown if there is racial/ethnic variability in this quality measure in pediatric emergency departments (PEDs). We aim to determine whether racial/ethnic differences exist in wait times for children presenting to PEDs and examine between-site and within-site differences.

METHODS

We conducted a retrospective cohort study for PED encounters in 2016 using the Pediatric Emergency Care Applied Research Network Registry, an aggregated deidentified electronic health registry comprising 7 PEDs. Patient encounters were included among all patients 18 years or younger at the time of the ED visit. We evaluated differences in emergency department wait time (time from arrival to first medical evaluation) considering patient race/ethnicity as the exposure.

RESULTS

Of 448,563 visits, median wait time was 35 minutes (interquartile range, 17-71 minutes). Compared with non-Hispanic White (NHW) children, non-Hispanic Black (NHB), Hispanic, and other race children waited 27%, 33%, and 12% longer, respectively. These differences were attenuated after adjusting for triage acuity level, mode of arrival, sex, age, insurance, time of day, and month [adjusted median wait time ratios (95% confidence intervals): 1.11 (1.10-1.12) for NHB, 1.12 (1.11-1.13) for Hispanic, and 1.05 (1.03-1.06) for other race children compared with NHW children]. Differences in wait time for NHB and other race children were no longer significant after adjusting for clinical site. Fully adjusted median wait times among Hispanic children were longer compared with NHW children [1.04 (1.03-1.05)].

CONCLUSIONS

In unadjusted analyses, non-White children experienced longer PED wait times than NHW children. After adjusting for illness severity, patient demographics, and overcrowding measures, wait times for NHB and other race children were largely determined by site of care. Hispanic children experienced longer within-site and between-site wait times compared with NHW children. Additional research is needed to understand structures and processes of care contributing to wait time differences between sites that disproportionately impact non-White patients.

Implicit Bias and Caring for Diverse Populations: Pediatric Trainee Attitudes and Gaps in Training

The objective of this study was to determine the attitudes, skill level, and preferred educational interventions of pediatric residents related to implicit bias and caring for diverse patient populations. A cross-sectional survey of pediatric residents at a single, large urban residency program was utilized. Surveys were completed by 88 (55%) residents who were 69% female and 35% non-White or mixed race. Almost all residents felt that it was very or extremely important to receive training on health disparities, diverse patient populations, and implicit bias. Self-assessment of skill level revealed that residents felt confident in areas often covered by cultural competency curricula, such as interpreter use, but were less confident in other areas. The top 3 areas identified for further training included implicit bias, working with transgender and gender nonconforming patients, and weight bias. For the majority of diversity and bias-related skills, prior training was significantly correlated with higher skill level (P < .05).

Experiences of underrepresented faculty in pediatric emergency medicine

OBJECTIVE

The aim of this study is to elucidate the unique challenges faced by pediatric emergency medicine (PEM) physicians from racial/ethnic groups underrepresented in medicine (URiM).

METHODS

This study is a subanalysis of data from 18 URiM faculty from a sample of 51 semistructured key informant interviews with PEM faculty in the top NIH-funded pediatric departments and highest-volume pediatric EDs in the country. Faculty are from eight hospitals representing a spectrum of geographic locations including the northeastern, midwestern, western, and southern regions of the country.

RESULTS

Of 18 study participants, the majority were Black (72.2%) and female (83.3%). Three main thematic categories were identified: challenges related to race, support systems, and suggested strategies to improve diversity and inclusion in PEM. A common race-related experience was microaggressions from colleagues and patients. Additionally, when attempting to lead and assert themselves, URiM women in particular were perceived as "angry" and "intimidating" in a way that non-URiM peers were not. As a result of these negative experiences, participants described the need to go above and beyond to prove themselves. Such pressure produced stress and feelings of isolation. Participants combatted these stressors through resilience strategies such as formal mentorship and peer and family support. Participants indicated the need to increase diversity and create more inclusive work environments, which would benefit both URiM physician wellness and the diverse patients they serve.

CONCLUSION

Those URiM in PEM face subtle racial discrimination at an institutional, peer, and patient level. The stress caused by this discrimination may further contribute to physician burnout in PEM. While URiMs adopt individual resilience strategies, their unique challenges suggest the need for departmental and institutional efforts to promote greater diversity and inclusion for physician wellness, retention, and quality patient care.

Racial and ethnic disparities in the delayed diagnosis of appendicitis among children

BACKGROUND

Appendicitis is the most common surgical condition in pediatric emergency department (ED) patients. Prompt diagnosis can reduce morbidity, including appendiceal perforation. The goal of this study was to measure racial/ethnic differences in rates of 1) appendiceal perforation, 2) delayed diagnosis of appendicitis, and 3) diagnostic imaging during prior visit(s).

METHODS

This was a 3-year multicenter (seven EDs) retrospective cohort study of children diagnosed with appendicitis using the Pediatric Emergency Care Applied Research Network Registry. Delayed diagnosis was defined as having at least one prior ED visit within 7 days preceding appendicitis diagnosis. We performed multivariable logistic regression to measure associations of race/ethnicity (non-Hispanic [NH]-white, NH-Black, Hispanic, other) with 1) appendiceal perforation, 2) delayed diagnosis of appendicitis, and 3) diagnostic imaging during prior visit(s).

RESULTS

Of 7,298 patients with appendicitis and documented race/ethnicity, 2,567 (35.2%) had appendiceal perforation. In comparison to NH-whites, NH-Black children had higher likelihood of perforation (36.5% vs. 34.9%; adjusted odds ratio [aOR] = 1.21 [95% confidence interval {CI} = 1.01 to 1.45]). A total of 206 (2.8%) had a delayed diagnosis of appendicitis. NH-Black children were more likely to have delayed diagnoses (4.7% vs. 2.0%; aOR = 1.81 [95% CI = 1.09 to 2.98]). Eighty-nine (43.2%) patients with delayed diagnosis had abdominal imaging during their prior visits. In comparison to NH-whites, NH-Black children were less likely to undergo any imaging (28.2% vs. 46.2%; aOR = 0.41 [95% CI = 0.18 to 0.96]) or definitive imaging (e.g., ultrasound/computed tomography/magnetic resonance imaging; 10.3% vs. 35.9%; aOR = 0.15 [95% CI = 0.05 to 0.50]) during prior visits.

CONCLUSIONS

In this multicenter cohort, there were racial disparities in appendiceal perforation. There were also racial disparities in rates of delayed diagnosis of appendicitis and diagnostic imaging during prior ED visits. These disparities in diagnostic imaging may lead to delays in appendicitis diagnosis and, thus, may contribute to higher perforation rates demonstrated among minority children.

Impact of patient race/ethnicity on emergency department management of pediatric gastroenteritis in the setting of a clinical pathway

BACKGROUND

Acute gastroenteritis (AGE) is a common pediatric diagnosis in emergency medicine, accounting for 1.7 million visits annually. Little is known about racial/ethnic differences in care in the setting of standardized care models.

METHODS

We used quality improvement data for children 6 months to 18 years presenting to a large, urban pediatric emergency department (ED) treated via a clinical pathway for AGE/dehydration between 2011 and 2018. Race/ethnicity was evaluated as a single variable (non-Hispanic [NH]-White, NH-Black, Hispanic, and NH-other) related to ondansetron and intravenous fluid (IVF) administration, ED length of stay (LOS), hospital admission, and ED revisits using multivariable regression.

RESULTS

Of 30,849 ED visits for AGE/dehydration, 18.0% were NH-White, 57.2% NH-Black, 12.5% Hispanic, and 12.3% NH-other. Multivariable mixed-effects generalized linear regression controlling for age, sex, triage acuity, payer, and language revealed that, compared to NH-White patients, NH-other patients were more likely to receive ondansetron (adjusted odds ratio [95% CI] = 1.30 [1.17 to 1.43]). NH-Black, Hispanic, and NH-other patients were significantly less likely to receive IVF (0.59 [0.53 to 0.65]; 0.74 [0.64 to 0.84]; 0.74 [0.65 to 0.85]) or be admitted to the hospital (0.54 [0.45 to 0.64]; 0.62 [0.49 to 0.78]; 0.76 [0.61 to 0.94]), respectively. NH-Black and Hispanic patients had shorter LOS (median = 245 minutes for NH-White, 176 NH-Black, 199 Hispanic, and 203 NH-other patients) without significant differences in ED revisits.

CONCLUSIONS

Despite the presence of a clinical pathway to guide care, NH-Black, Hispanic, and NH-other children presenting to the ED with AGE/dehydration were less likely to receive IVF or hospital admission and had shorter LOS compared to NH-White counterparts. There was no difference in patient revisits, which suggests discretionary overtreatment of NH-White patients, even with clinical guidelines in place. Further research is needed to understand the drivers of differences in care to develop interventions promoting equity in pediatric emergency care.

Myopericarditis in a previously healthy adolescent male following COVID-19 vaccination: A case report

We report the case of a previously healthy 16‐year‐old male who developed myopericarditis following the second dose of his Pfizer‐BioNTech COVID‐19 vaccine, with no other identified triggers. Adolescents and young adults experiencing chest pain after COVD‐19 vaccination should seek emergent medical care, and emergency providers should have a low threshold to consider and evaluate for myopericarditis. More data are needed to better understand the potential association between COVID‐19 vaccines and myopericarditis. If a true causal link is identified, the risk must also be viewed in context with the millions of patients who have been safely vaccinated and the known morbidity and mortality from COVID‐19 infection. As we see widespread vaccine rollout, it is important that all potential adverse reactions are reported as we continue to monitor for more rare but potentially serious side effects not identified in vaccination trials.

Executions and Police Conflicts Involving Children, Adolescents and Young Adults

Police violence in the United States represents a pressing public health crisis impacting youth, particularly youth of color. This article reviews the recent epidemiology of police executions and conflicts involving children, adolescents, and young adults. The roles of social determinants of health and centuries-long history of white supremacy and racism as root causes of adverse policing are emphasized. The article summarizes the evidence as to how direct and vicarious experiences of police violence impact youth academic, behavioral, and health outcomes. Recommendations are provided for pediatricians to address this public health crisis through clinical practice, education, advocacy, and research.

Structuring Poverty: How Racism Shapes Child Poverty and Child and Adolescent Health

Black, Native, and Latinx populations represent the racial and ethnic groups most impacted by poverty. This unequal distribution of poverty must be understood as a consequence of policy decisions-some that have sanctioned violence and others that have created norms-that continue to shape who has access to power, resources, rights, and protections. In this review, we draw on scholarship from multiple disciplines, including pediatrics, public health, environmental health, epidemiology, social and biomedical science, law, policy, and urban planning to explore the central question-What is the relationship between structural racism, poverty, and pediatric health? We discuss historic and present-day events that are critical to the understanding of poverty in the context of American racism and pediatric health. We challenge conventional paradigms that treat racialized poverty as an inherent part of American society. We put forth a conceptual framework to illustrate how white supremacy and American capitalism drive structural racism and shape the racial distribution of resources and power where children and adolescents live, learn, and play, ultimately contributing to pediatric health inequities. Finally, we offer antipoverty strategies grounded in antiracist practices that contend with the compounding, generational impact of racism and poverty on heath to improve child, adolescent, and family health.

Effect of supplementation of a dairy-originated probiotic bacterium, Propionibacterium freudenreichii subsp. freudenreichii, on the cecal microbiome of turkeys challenged with multidrug-resistant Salmonella Heidelberg

A dairy-originated probiotic bacterium, Propionibacterium freudenreichii subsp. freudenreichii B3523 (PF) was found to be effective in reducing multidrug-resistant Salmonella Heidelberg (MDR SH) colonization in turkey poults (2-week-old) and growing (7-week-old) and finishing (12-week-old) turkeys. In this study, we explored the potential for microbiome modulation in the cecum of turkeys of different age groups due to PF supplementation in conjunction with MDR SH challenge. One-day-old commercial turkey poults were allocated to 3 treatment groups: negative control (N; turkeys without PF supplementation or SH challenge), SH control (S; turkeys challenged with SH without PF supplementation), and test group (P; turkeys supplemented with PF and challenged with SH). Turkeys were supplemented with 10¹⁰ CFU PF in 5-gallon (18.9 L) water until 7 or 12 week of age. At the 6th or 11^th wk, turkeys were challenged with SH at 10⁶ and 10⁸ CFU/bird by crop gavage, respectively. After 2 and 7 d of challenge (2-d postinoculation [PI] and 7-d PI, respectively), cecal samples were collected and microbiome analysis was conducted using Illumina MiSeq. The experiments were repeated twice with 8 and 10 turkeys/group for 7- and 12-wk studies, respectively. Results indicated that the species richness and abundance (Shannon diversity index) was similar among the treatment groups. However, treatments caused apparent clustering of the samples among each other (P < 0.05). Firmicutes was the predominant phylum in the growing and finishing turkey cecum which was evenly distributed among the treatments except on wk 12 where the relative abundance of Firmicutes was significantly higher in P than in N (P = 0.02). The MDR SH challenge resulted in modulation of microflora such as Streptococcus, Gordonibacter, and Turicibacter (P < 0.05) in the S groups compared with the P and N groups, known to be associated with inflammatory responses in birds and mammals. The supplementation of PF increased the relative abundance of carbohydrate-fermenting and short-chain fatty acid–producing genera in the P group compared with the S group (P < 0.05). Moreover, the results revealed that PF supplementation potentially modulated the beneficial microbiota in the P group, which could mitigate SH carriage in turkeys.

Racial and Ethnic Differences in Emergency Department Pain Management of Children With Fractures

OBJECTIVES

To test the hypotheses that minority children with long-bone fractures are less likely to (1) receive analgesics, (2) receive opioid analgesics, and (3) achieve pain reduction.

METHODS

We performed a 3-year retrospective cross-sectional study of children <18 years old with long-bone fractures using the Pediatric Emergency Care Applied Research Network Registry (7 emergency departments). We performed bivariable and multivariable logistic regression to measure the association between patient race and ethnicity and (1) any analgesic, (2) opioid analgesic, (3) ≥2-point pain score reduction, and (4) optimal pain reduction (ie, to mild or no pain).

RESULTS

In 21 069 visits with moderate-to-severe pain, 86.1% received an analgesic and 45.4% received opioids. Of 8533 patients with reassessment of pain, 89.2% experienced ≥2-point reduction in pain score and 62.2% experienced optimal pain reduction. In multivariable analyses, minority children, compared with non-Hispanic (NH) white children, were more likely to receive any analgesics (NH African American: adjusted odds ratio [aOR] 1.72 [95% confidence interval 1.51-1.95]; Hispanic: 1.32 [1.16-1.51]) and achieve ≥2-point reduction in pain (NH African American: 1.42 [1.14-1.76]; Hispanic: 1.38 [1.04-1.83]) but were less likely to receive opioids (NH African American: aOR 0.86 [0.77-0.95]; Hispanic: aOR 0.86 [0.76-0.96]) or achieve optimal pain reduction (NH African American: aOR 0.78 [0.67-0.90]; Hispanic: aOR 0.80 [0.67-0.95]).

CONCLUSIONS

There are differences in process and outcome measures by race and ethnicity in the emergency department management of pain among children with long-bone fractures. Although minority children are more likely to receive analgesics and achieve ≥2-point reduction in pain, they are less likely to receive opioids and achieve optimal pain reduction.

In-situ measurement of pyrolysis and combustion gases from biomass burning using swept wavelength external cavity quantum cascade lasers

Broadband high-speed absorption spectroscopy using swept-wavelength external cavity quantum cascade lasers (ECQCLs) is applied to measure multiple pyrolysis and combustion gases in biomass burning experiments. Two broadly-tunable swept-ECQCL systems were used, with the first tuned over a range of 2089-2262 cm^-1 (4.42-4.79 µm) to measure spectra of CO₂, H₂O, and CO. The second was tuned over a range of 920-1150 cm^-1 (8.70-10.9 µm) to measure spectra of ammonia (NH₃), ethene (C₂H₄), and methanol (MeOH). Absorption spectra were measured continuously at a 100 Hz rate throughout the burn process, including inhomogeneous flame regions, and analyzed to determine time-resolved gas concentrations and temperature. The results provide in-situ, dynamic information regarding gas-phase species as they are generated, close to the biomass fuel source.

Racial Differences in Sepsis Recognition in the Emergency Department

OBJECTIVES

We assessed racial differences in sepsis recognition in a pediatric emergency department (ED) with an established electronic sepsis alert system.

METHODS

Quality-improvement data from June 1, 2016 to May 31, 2017 was used in this retrospective cohort study. All ED visits were included for non-Hispanic black (NHB) and non-Hispanic white (NHW) patients. The sepsis pathway was activated through the alert, 2 stages and a huddle, or outside of the alert using clinician judgment alone. We evaluated racial differences in the frequency of alerts and sepsis pathway activation within and outside of the alert. Multivariable regression adjusted for high-risk condition, sex, age, and insurance.

RESULTS

There were 97 338 ED visits: 56 863 (58.4%) and 23 008 (23.6%) from NHBs and NHWs, respectively. NHWs were more likely than NHBs to have a positive second alert (adjusted odds ratio [aOR] 2.4; 95% confidence interval [CI] 2.1-2.8). NHWs were more likely than NHBs to have the sepsis pathway activated (aOR 1.4; 95% CI 1.02-2.1). Of those treated within the alert, there was no difference in pathway activation (aOR 0.93; 95% CI 0.62-1.4). Of those recognized by clinicians when the alert did not fire, NHWs were more likely than NHBs to be treated (aOR 3.4; 95% CI 1.8-6.4).

CONCLUSIONS

NHWs were more likely than NHBs to be treated for sepsis, although this difference was specifically identified in the subset of patients treated for sepsis outside of the alert. This suggests that an electronic alert reduces racial differences compared with clinician judgment alone.

Racial and Ethnic Differences in Antibiotic Use for Viral Illness in Emergency Departments

BACKGROUND AND OBJECTIVES

In the primary care setting, there are racial and ethnic differences in antibiotic prescribing for acute respiratory tract infections (ARTIs). Viral ARTIs are commonly diagnosed in the pediatric emergency department (PED), in which racial and ethnic differences in antibiotic prescribing have not been previously reported. We sought to investigate whether patient race and ethnicity was associated with differences in antibiotic prescribing for viral ARTIs in the PED.

METHODS

This is a retrospective cohort study of encounters at 7 PEDs in 2013, in which we used electronic health data from the Pediatric Emergency Care Applied Research Network Registry. Multivariable logistic regression was used to examine the association between patient race and ethnicity and antibiotics administered or prescribed among children discharged from the hospital with viral ARTI. Children with bacterial codiagnoses, chronic disease, or who were immunocompromised were excluded. Covariates included age, sex, insurance, triage level, provider type, emergency department type, and emergency department site.

RESULTS

Of 39 445 PED encounters for viral ARTIs that met inclusion criteria, 2.6% (95% confidence interval [CI] 2.4%-2.8%) received antibiotics, including 4.3% of non-Hispanic (NH) white, 1.9% of NH black, 2.6% of Hispanic, and 2.9% of other NH children. In multivariable analyses, NH black (adjusted odds ratio [aOR] 0.44; CI 0.36-0.53), Hispanic (aOR 0.65; CI 0.53-0.81), and other NH (aOR 0.68; CI 0.52-0.87) children remained less likely to receive antibiotics for viral ARTIs.

CONCLUSIONS

Compared with NH white children, NH black and Hispanic children were less likely to receive antibiotics for viral ARTIs in the PED. Future research should seek to understand why racial and ethnic differences in overprescribing exist, including parental expectations, provider perceptions of parental expectations, and implicit provider bias.

Implicit Bias in Pediatric Academic Medicine

OBJECTIVE

Despite known benefits of diversity, certain racial/ethnic groups remain underrepresented in academic pediatrics. Little research exists regarding unconscious racial attitudes among pediatric faculty responsible for decisions on workforce recruitment and retention in academia. This study sought to describe levels of unconscious racial bias and perceived barriers to minority recruitment and retention among academic pediatric faculty leaders.

METHODS

Authors measured unconscious racial bias in a sample of pediatric faculty attending diversity workshops conducted at local and national meetings in 2015. A paper version of the validated Implicit Association Test (IAT) measured unconscious racial bias. Subjects also reported perceptions about minority recruitment and retention.

RESULTS

Of 68 eligible subjects approached, 58 (85%) consented and completed the survey with IAT. Of participants, 83% had leadership roles and 93% were involved in recruitment. Participants had slight pro-white/anti-black bias on the IAT (M = 0.28, SD = 0.49). There were similar IAT scores among participants in leadership roles (M = 0.33, SD = 0.47) and involved in recruitment (M = 0.28, SD = 0.43). Results did not differ when comparing participants in local workshops to the national workshop (n = 36, M = 0.29, SD = 0.40 and n = 22, M = 0.27, SD = 0.49 respectively; p = 0.88). Perceived barriers to minority recruitment and retention included lack of minority mentors, poor recruitment efforts, and lack of qualified candidates.

CONCLUSIONS

Unconscious pro-white/anti-black racial bias was identified in this sample of academic pediatric faculty and leaders. Further research is needed to examine how unconscious bias impacts decisions in academic pediatric workforce recruitment. Addressing unconscious bias and perceived barriers to minority recruitment and retention represent opportunities to improve diversity efforts.

The Impact of Cognitive Stressors in the Emergency Department on Physician Implicit Racial Bias

OBJECTIVES

The emergency department (ED) is characterized by stressors (e.g., fatigue, stress, time pressure, and complex decision-making) that can pose challenges to delivering high-quality, equitable care. Although it has been suggested that characteristics of the ED may exacerbate reliance on cognitive heuristics, no research has directly investigated whether stressors in the ED impact physician racial bias, a common heuristic. We seek to determine if physicians have different levels of implicit racial bias post-ED shift versus preshift and to examine associations between demographics and cognitive stressors with bias.

METHODS

This repeated-measures study of resident physicians in a pediatric ED used electronic pre- and postshift assessments of implicit racial bias, demographics, and cognitive stressors. Implicit bias was measured using the Race Implicit Association Test (IAT). Linear regression models compared differences in IAT scores pre- to postshift and determined associations between participant demographics and cognitive stressors with postshift IAT and pre- to postshift difference scores.

RESULTS

Participants (n = 91) displayed moderate prowhite/antiblack bias on preshift (mean ± SD = 0.50 ± 0.34, d = 1.48) and postshift (mean ± SD = 0.55 ± 0.39, d = 1.40) IAT scores. Overall, IAT scores did not differ preshift to postshift (mean increase = 0.05, 95% CI = -0.02 to 0.14, d = 0.13). Subanalyses revealed increased pre- to postshift bias among participants working when the ED was more overcrowded (mean increase = 0.09, 95% CI = 0.01 to 0.17, d = 0.24) and among those caring for >10 patients (mean increase = 0.17, 95% CI = 0.05 to 0.27, d = 0.47). Residents' demographics (including specialty), fatigue, busyness, stressfulness, and number of shifts were not associated with postshift IAT or difference scores. In multivariable models, ED overcrowding was associated with greater postshift bias (coefficient = 0.11 per 1 unit of NEDOCS score, SE = 0.05, 95% CI = 0.00 to 0.21).

CONCLUSIONS

While resident implicit bias remained stable overall preshift to postshift, cognitive stressors (overcrowding and patient load) were associated with increased implicit bias. Physicians in the ED should be aware of how cognitive stressors may exacerbate implicit racial bias.

Characterizing analgesic use during air medical transport of injured children

BACKGROUND

Pain management is an important aspect of emergency care for children suffering traumatic injuries.

OBJECTIVES

The objectives of this study were to characterize analgesic administration to injured children during air medical transport, to describe factors associated with analgesic use, and to examine the effects of patient race on analgesia.

METHODS

We used electronic records for patients transported by a regional air medical transport agency. We retrospectively examined data from 2003-2012 for patients ≤ 15 years old suffering traumatic injuries. We used bivariable analyses to identify associations for multivariable logistic regression models to determine factors associated with our outcomes -documentation of pain score and analgesic administration.

RESULTS

Of 5,057 patients, the median age was 8 (IQR 3-12) years. The majority of patients were male (66%, 95% CI 64-66%), were white non-Hispanic (83%, 95% CI 82-84%), and had no pain score documented (61%, 95% CI 60-62%). While only 15% of patients received analgesics overall, 70% with an initial pain score ≥ 5 received analgesics. In unadjusted models, non-white race was associated with lower odds of having a pain score documented (OR 0.52, 95% CI 0.44-0.62) and receiving analgesics (OR 0.64, 95% CI 0.50-0.82). After adjusting for confounders, there was no evidence of racial differences in pain management. Multivariable analysis revealed that younger age, lack of intravenous access, higher Glasgow Coma Scale, systolic blood pressure <100, transportation from the scene, initial pain score <5, and not having a pain score documented were associated with lower odds of receiving analgesics.

CONCLUSIONS

Few pediatric patients had pain scores documented and fewer received analgesics during air medical transport for injuries. Racial differences in analgesia seen in unadjusted analyses did not persist after controlling for confounders. Resources, training, and appropriate pain management protocols should be made available to facilitate pain assessment in children as a strategy for increasing appropriate analgesic use during transport.

Association of race and ethnicity with management of abdominal pain in the emergency department

OBJECTIVE

To determine if race/ethnicity-based differences exist in the management of pediatric abdominal pain in emergency departments (EDs).

METHODS

Secondary analysis of data from the 2006-2009 National Hospital Ambulatory Medical Care Survey regarding 2298 visits by patients ≤ 21 years old who presented to EDs with abdominal pain. Main outcomes were documentation of pain score and receipt of any analgesics, analgesics for severe pain (defined as ≥ 7 on a 10-point scale), and narcotic analgesics. Secondary outcomes included diagnostic tests obtained, length of stay (LOS), 72-hour return visits, and admission.

RESULTS

Of patient visits, 70.1% were female, 52.6% were from non-Hispanic white, 23.5% were from non-Hispanic black, 20.6% were from Hispanic, and 3.3% were from "other" racial/ethnic groups; patients' mean age was 14.5 years. Multivariate logistic regression models adjusting for confounders revealed that non-Hispanic black patients were less likely to receive any analgesic (odds ratio [OR]: 0.61; 95% confidence interval [CI]: 0.43-0.87) or a narcotic analgesic (OR: 0.38; 95% CI: 0.18-0.81) than non-Hispanic white patients (referent group). This finding was also true for non-Hispanic black and "other" race/ethnicity patients with severe pain (ORs [95% CI]: 0.43 [0.22-0.87] and 0.02 [0.00-0.19], respectively). Non-Hispanic black and Hispanic patients were more likely to have a prolonged LOS than non-Hispanic white patients (ORs [95% CI]: 1.68 [1.13-2.51] and 1.64 [1.09-2.47], respectively). No significant race/ethnicity-based disparities were identified in documentation of pain score, use of diagnostic procedures, 72-hour return visits, or hospital admissions.

CONCLUSIONS

Race/ethnicity-based disparities exist in ED analgesic use and LOS for pediatric abdominal pain. Recognizing these disparities may help investigators eliminate inequalities in care.

Impact of early human milk on sepsis and health-care costs in very low birth weight infants

OBJECTIVE

To study the incidence of sepsis and neonatal intensive care unit (NICU) costs as a function of the human milk (HM) dose received during the first 28 days post birth for very low birth weight (VLBW) infants.

STUDY DESIGN

Prospective cohort study of 175 VLBW infants. The average daily dose of HM (ADDHM) was calculated from daily nutritional data for the first 28 days post birth (ADDHM-Days 1-28). Other covariates associated with sepsis were used to create a propensity score, combining multiple risk factors into a single metric.

RESULT

The mean gestational age and birth weight were 28.1 ± 2.4 weeks and 1087 ± 252 g, respectively. The mean ADDHM-Days 1-28 was 54 ± 39 ml kg(-1) day(-1) (range 0-135). Binary logistic regression analysis controlling for propensity score revealed that increasing ADDHM-Days 1-28 was associated with lower odds of sepsis (odds ratio 0.981, 95% confidence interval 0.967-0.995, P=0.008). Increasing ADDHM-Days 1-28 was associated with significantly lower NICU costs.

CONCLUSION

A dose-response relationship was demonstrated between ADDHM-Days 1-28 and a reduction in the odds of sepsis and associated NICU costs after controlling for propensity score. For every HM dose increase of 10 ml kg(-1) day(-1), the odds of sepsis decreased by 19%. NICU costs were lowest in the VLBW infants who received the highest ADDHM-Days 1-28.

Comparative faecal microbiota of dogs with and without calcium oxalate stones

AIMS

The absence of enteric oxalate-metabolizing bacterial species (OMBS) increases the likelihood of calcium oxalate (CaOx) urolithiasis in humans and dogs. The goal of this study was to compare the gut microbiota of healthy dogs and CaOx stone formed dogs (CaOx-dogs), especially with respect to OMBS.

METHODS AND RESULTS

Faecal samples from healthy and CaOx-dogs were obtained to analyse the hindgut microbiota by sequencing the V3 region of bacterial 16S rDNA. In total, 1223 operational taxonomic units (OTUs) were identified at 97% identity. Only 38% of these OTUs were shared by both groups. Significant differences in the relative abundance of 152 OTUs and 36 genera were observed between the two groups of dogs.

CONCLUSIONS

The faecal microbiota of healthy dogs is distinct from that of CaOx-dogs, indicating that the microbiota is altered in CaOx-dogs.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first study that has compared the gut microbial diversity in healthy and CaOx-dogs. Results of this study indicate the future need for functional and comparative analyses of the total array of oxalate-metabolizing genes between healthy and CaOx stone formers, rather than focusing on specific bacterial species, to understand the critical role of OMBS in CaOx urolithiasis.

Allocation of scarce resources during mass casualty events

OBJECTIVES

This systematic review sought to identify the best available evidence regarding strategies for allocating scarce resources during mass casualty events (MCEs). Specifically, the review addresses the following questions: (1) What strategies are available to policymakers to optimize the allocation of scarce resources during MCEs? (2) What strategies are available to providers to optimize the allocation of scarce resources during MCEs? (3) What are the public's key perceptions and concerns regarding the implementation of strategies to allocate scarce resources during MCEs? (4) What methods are available to engage providers in discussions regarding the development and implementation of strategies to allocate scarce resources during MCEs?

DATA SOURCES

We searched Medline, Scopus, Embase, CINAHL (Cumulative Index to Nursing and Allied Health Literature), Global Health, Web of Science®, and the Cochrane Database of Systematic Reviews from 1990 through 2011. To identify relevant non-peer-reviewed reports, we searched the New York Academy of Medicine's Grey Literature Report. We also reviewed relevant State and Federal plans, peer-reviewed reports and papers by nongovernmental organizations, and consensus statements published by professional societies. We included both English- and foreign-language studies.

REVIEW METHODS

Our review included studies that evaluated tested strategies in real-world MCEs as well as strategies tested in drills, exercises, or computer simulations, all of which included a comparison group. We reviewed separately studies that lacked a comparison group but nonetheless evaluated promising strategies. We also identified consensus recommendations developed by professional societies or government panels. We reviewed existing State plans to examine the current state of planning for scarce resource allocation during MCEs. Two investigators independently reviewed each article, abstracted data, and assessed study quality.

RESULTS

We considered 5,716 reports for this comparative effectiveness review (CER); we ultimately included 170 in the review. Twenty-seven studies focus on strategies for policymakers. Among this group were studies that examined various ways to distribute biological countermeasures more efficiently during a bioterror attack or influenza pandemic. They provided modest evidence that the way these systems are organized influences the speed of distribution. The review includes 119 studies that address strategies for providers. A number of these studies provided evidence suggesting that commonly used triage systems do not perform consistently in actual MCEs. The number of high-quality studies addressing other specific strategies was insufficient to support firm conclusions about their effectiveness. Only 10 studies included strategies that consider the public's perspective. However, these studies were consistent in their findings. In particular, the public believes that resource allocation guidelines should be simple and consistent across health care facilities but should allow facilities some flexibility to make allocation decisions based on the specific demand and supply situation. The public also believes that a successful allocation system should balance the goals of ensuring the functioning of society, saving the greatest number of people, protecting the most vulnerable people, reducing deaths and hospitalizations, and treating people fairly and equitably. The remaining 14 studies provided strategies for engaging providers in discussions about allocating and managing scarce medical resources. These studies did not identify one engagement approach as clearly superior; however, they consistently noted the importance of a broad, inclusive, and systematic engagement process.

CONCLUSIONS

Scientific research to identify the most effective adaptive strategies to implement during MCEs is an emerging area. While it remains unclear which of the many options available to policymakers and providers will be most effective, ongoing efforts to develop a focused, well-organized program of applied research should help to identify the optimal methods, techniques, and technologies to strengthen our nation's capacity to respond to MCEs.

Gamma-ray emission concurrent with the nova in the symbiotic binary V407 Cygni

Novae are thermonuclear explosions on a white dwarf surface fueled by mass accreted from a companion star. Current physical models posit that shocked expanding gas from the nova shell can produce x-ray emission, but emission at higher energies has not been widely expected. Here, we report the Fermi Large Area Telescope detection of variable gamma-ray emission (0.1 to 10 billion electron volts) from the recently detected optical nova of the symbiotic star V407 Cygni. We propose that the material of the nova shell interacts with the dense ambient medium of the red giant primary and that particles can be accelerated effectively to produce pi(0) decay gamma-rays from proton-proton interactions. Emission involving inverse Compton scattering of the red giant radiation is also considered and is not ruled out.

Spectrum of the isotropic diffuse gamma-ray emission derived from first-year Fermi Large Area Telescope data

We report on the first Fermi Large Area Telescope (LAT) measurements of the so-called "extragalactic" diffuse gamma-ray emission (EGB). This component of the diffuse gamma-ray emission is generally considered to have an isotropic or nearly isotropic distribution on the sky with diverse contributions discussed in the literature. The derivation of the EGB is based on detailed modeling of the bright foreground diffuse Galactic gamma-ray emission, the detected LAT sources, and the solar gamma-ray emission. We find the spectrum of the EGB is consistent with a power law with a differential spectral index gamma = 2.41 +/- 0.05 and intensity I(>100 MeV) = (1.03 +/- 0.17) x 10(-5) cm(-2) s(-1) sr(-1), where the error is systematics dominated. Our EGB spectrum is featureless, less intense, and softer than that derived from EGRET data.

Fermi large area telescope measurements of the diffuse gamma-ray emission at intermediate galactic latitudes

The diffuse galactic gamma-ray emission is produced by cosmic rays (CRs) interacting with the interstellar gas and radiation field. Measurements by the Energetic Gamma-Ray Experiment Telescope (EGRET) instrument on the Compton Gamma-Ray Observatory indicated excess gamma-ray emission greater, > or approximately equal to 1 GeV relative to diffuse galactic gamma-ray emission models consistent with directly measured CR spectra (the so-called "EGRET GeV excess"). The Large Area Telescope (LAT) instrument on the Fermi Gamma-Ray Space Telescope has measured the diffuse gamma-ray emission with improved sensitivity and resolution compared to EGRET. We report on LAT measurements for energies 100 MeV to 10 GeV and galactic latitudes 10 degrees < or = |b| < or = 20 degrees. The LAT spectrum for this region of the sky is well reproduced by a diffuse galactic gamma-ray emission model that is consistent with local CR spectra and inconsistent with the EGRET GeV excess.

Detection of high-energy gamma-ray emission from the globular cluster 47 Tucanae with Fermi

We report the detection of gamma-ray emissions above 200 megaelectron volts at a significance level of 17sigma from the globular cluster 47 Tucanae, using data obtained with the Large Area Telescope onboard the Fermi Gamma-ray Space Telescope. Globular clusters are expected to emit gamma rays because of the large populations of millisecond pulsars that they contain. The spectral shape of 47 Tucanae is consistent with gamma-ray emission from a population of millisecond pulsars. The observed gamma-ray luminosity implies an upper limit of 60 millisecond pulsars present in 47 Tucanae.

Detection of 16 gamma-ray pulsars through blind frequency searches using the Fermi LAT

Pulsars are rapidly rotating, highly magnetized neutron stars emitting radiation across the electromagnetic spectrum. Although there are more than 1800 known radio pulsars, until recently only seven were observed to pulse in gamma rays, and these were all discovered at other wavelengths. The Fermi Large Area Telescope (LAT) makes it possible to pinpoint neutron stars through their gamma-ray pulsations. We report the detection of 16 gamma-ray pulsars in blind frequency searches using the LAT. Most of these pulsars are coincident with previously unidentified gamma-ray sources, and many are associated with supernova remnants. Direct detection of gamma-ray pulsars enables studies of emission mechanisms, population statistics, and the energetics of pulsar wind nebulae and supernova remnants.

Growth, processing, and optical properties of epitaxial Er2O3 on silicon

Erbium-doped materials have been investigated for generating and amplifying light in low-power chip-scale optical networks on silicon, but several effects limit their performance in dense microphotonic applications. Stoichiometric ionic crystals are a potential alternative that achieve an Er(3+) density 100 x greater. We report the growth, processing, material characterization, and optical properties of single-crystal Er (2)O(3) epitaxially grown on silicon. A peak Er(3+) resonant absorption of 364 dB/cm at 1535 nm with minimal background loss places a high limit on potential gain. Using high-quality microdisk resonators, we conduct thorough C/L-band radiative efficiency and lifetime measurements and observe strong upconverted luminescence near 550 and 670 nm.

The Fermi Gamma-Ray Space Telescope discovers the pulsar in the young galactic supernova remnant CTA 1

Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.

Adiabatic self-tuning in a silicon microdisk optical resonator

We demonstrate a method for adiabatically self-tuning a silicon microdisk resonator. This mechanism is not only able to sensitively probe the fast nonlinear cavity dynamics, but also provides various optical functionalities like pulse compression, shaping, and tunable time delay.

A proposal for highly tunable optical parametric oscillation in silicon micro-resonators

We propose a novel scheme for continuous-wave pumped optical parametric oscillation (OPO) inside silicon micro-resonators. The proposed scheme not only requires a relative low lasing threshold, but also exhibits extremely broad tunability extending from the telecom band to mid infrared.

An optical fiber-taper probe for wafer-scale microphotonic device characterization

A small depression is created in a straight optical fiber taper to form a local probe suitable for studying closely spaced, planar microphotonic devices. The tension of the "dimpled" taper controls the probe-sample interaction length and the level of noise present during coupling measurements. Practical demonstrations with high-Q silicon microcavities include testing a dense array of undercut microdisks (maximum Q = 3.3 x 10(6)) and a planar microring (Q = 4.8 x 10(6)).

Identification by subtractive suppression hybridization of bacteria-induced genes expressed in Manduca sexta fat body

Insect immune processes are mediated by programs of differential gene expression. To understand the molecular regulation of the immune response in the tobacco hornworm, Manduca sexta, the relevant subset of differentially expressed genes of interest must be identified, cloned and studied in detail. In this study, suppression subtractive hybridization, a PCR-based method for cDNA subtraction was performed to identify mRNAs from fat body of immunized larvae that are not present (or present at a low level) in control larvae. A subtracted cDNA library enriched in immune-inducible genes was constructed. Northern blot analysis of a sample of clones from our subtracted library indicated that >90% of the clones randomly selected from the subtracted library are immune inducible. Sequence analysis of 238 expressed sequence tags (ESTs) revealed that 120 ESTs, representing 54 distinct genes or gene families, had sequences identical or similar to previously characterized genes, some of which have been confirmed to be involved in innate immunity. These ESTs were categorized into seven groups, including pattern recognition proteins, serine proteinases and their inhibitors, and antimicrobial proteins. 112 ESTs, about 47.5% of the library, showed no significant similarity to any known genes. The sequences identified in this M. sexta library reflect our knowledge of insect immune strategies and may facilitate better understanding of insect immune responses.

Resistance to serum complement, iss, and virulence of avian Escherichia coli

Control of avian colibacillosis is hampered by lack of easily identifiable markers for virulent Escherichia coli. Resistance to serum complement appears to be a widespread trait of virulent avian E. coil, suggesting that bacterial factors promoting survival in serum may be useful in discriminating between virulent and avirulent isolates. Such distinguishing factors may prove useful in diagnostic protocols or as targets in future colibacillosis control protocols. Interestingly, the factors responsible for resistance to complement differ in the E. coli isolated from mammalian and avian hosts, which may reflect differences in the nature of avian and mammalian colibacillosis. In some cases, genetic determinants for serum complement resistance in avian E. coli are found on aerobactin- or Colicin V-encoding plasmids. One such gene, iss, first described for its role in the serum resistance associated with a ColV plasmid from a human E. coli isolate, occurs much more frequently in isolates from birds with colibacillosis than in faecal isolates from healthy birds. Efforts to identify the genomic location of iss in a single, virulent avian E. coli isolate have revealed that it occurs in association with several purported virulence genes, all linked to a large conjugative R plasmid. At this time, it is not known whether iss merely marks the presence of a larger pathogenicity unit or is itself a contributor to virulence. Nevertheless, the presence of the complement-resistance determinant, iss, may be a marker of virulent avian E. coli exploitable in controlling avian colibacillosis.