Outcomes associated with initial narrow-spectrum versus broad-spectrum antibiotics in children hospitalized with urinary tract infections

OBJECTIVE

The aim of this study is to describe the proportion of children hospitalized with urinary tract infections (UTIs) who receive initial narrow- versus broad-spectrum antibiotics across children's hospitals and explore whether the use of initial narrow-spectrum antibiotics is associated with different outcomes.

DESIGN, SETTING AND PARTICIPANTS

We performed a retrospective cohort analysis of children aged 2 months to 17 years hospitalized with UTI (inclusive of pyelonephritis) using the Pediatric Health Information System (PHIS) database.

MAIN OUTCOME AND MEASURES

We analyzed the proportions of children initially receiving narrow- versus broad-spectrum antibiotics; additionally, we compiled antibiogram data for common uropathogenic organisms from participating hospitals to compare with the observed antibiotic susceptibility patterns. We examined the association of antibiotic type with adjusted outcomes including length of stay (LOS), costs, and 7- and 30-day emergency department (ED) revisits and hospital readmissions.

RESULTS

We identified 10,740 hospitalizations for UTI across 39 hospitals. Approximately 5% of encounters demonstrated initial narrow-spectrum antibiotics, with hospital-level narrow-spectrum use ranging from <1% to 25%. Approximately 80% of hospital antibiograms demonstrated >80% Escherichia coli susceptibility to cefazolin. In adjusted models, those who received initial narrow-spectrum antibiotics had shorter LOS (narrow-spectrum: 33.1 (95% confidence interval [CI]: 30.8-35.4) h versus broad-spectrum: 46.1 (95% CI: 44.1-48.2) h) and reduced costs [narrow-spectrum: $4570 ($3751-5568) versus broad-spectrum: $5699 ($5005-$6491)]. There were no differences in ED revisits or hospital readmissions. In summary, children's hospitals have low rates of narrow-spectrum antibiotic use for UTIs despite many reporting high rates of cefazolin-susceptible E. coli. These findings, coupled with the observed decreased LOS and costs among those receiving narrow-spectrum antibiotics, highlight potential antibiotic stewardship opportunities.

Increasing the Use of Enteral Antibiotics in Hospitalized Children With Uncomplicated Infections

BACKGROUND

Route of administration is an important component of antimicrobial stewardship. Early transition from intravenous to enteral antibiotics in hospitalized children is associated with fewer catheter-related adverse events, as well as decreased costs and length of stay. Our aim was to increase the percentage of enteral antibiotic doses for hospital medicine patients with uncomplicated common bacterial infections (community-acquired pneumonia, skin and soft tissue infection, urinary tract infection, neck infection) from 50% to 80% in 6 months.

METHODS

We formed a multidisciplinary team to evaluate key drivers and design plan-do-study-act cycles. Interventions included provider education, structured discussion at existing team huddles, and pocket-sized printed information. Our primary measure was the percentage of antibiotic doses given enterally to patients receiving other enteral medications. Secondary measures included antibiotic cost, number of peripheral intravenous catheters, length of stay, and 7-day readmission. We used statistical process control charts to track our measures.

RESULTS

Over a 6-month baseline period and 12 months of improvement work, we observed 3183 antibiotic doses (888 in the baseline period, 2295 doses during improvement work). We observed an increase in the percentage of antibiotic doses given enterally per week for eligible patients from 50% to 67%. We observed decreased antibiotic costs and fewer peripheral intravenous catheters per encounter after the interventions. There was no change in length of stay or readmissions.

CONCLUSIONS

We observed increased enteral antibiotic doses for children hospitalized with common bacterial infections. Interventions targeting culture change and communication were associated with sustained improvement.

Changing patterns of routine laboratory testing over time at children's hospitals

BACKGROUND

Research into low-value routine testing at children's hospitals has not consistently evaluated changing patterns of testing over time.

OBJECTIVES

To identify changes in routine laboratory testing rates at children's hospitals over ten years and the association with patient outcomes.

DESIGN, SETTINGS, AND PARTICIPANTS

We performed a multi-center, retrospective cohort study of children aged 0-18 hospitalized with common, lower-severity diagnoses at 28 children's hospitals in the Pediatric Health Information Systems database.

MAIN OUTCOMES AND MEASURES

We calculated average annual testing rates for complete blood counts, electrolytes, and inflammatory markers between 2010 and 2019 for each hospital. A > 2% average testing rate change per year was defined as clinically meaningful and used to separate hospitals into groups: increasing, decreasing, and unchanged testing rates. Groups were compared for differences in length of stay, cost, and 30-day readmission or ED revisit, adjusted for demographics and case mix index.

RESULTS

Our study included 576,572 encounters for common, low-severity diagnoses. Individual hospital testing rates in each year of the study varied from 0.3 to 1.4 tests per patient day. The average yearly change in hospital-specific testing rates ranged from -6% to +7%. Four hospitals remained in the lowest quartile of testing and two in the highest quartile throughout all ten years of the study. We grouped hospitals with increasing (8), decreasing (n = 5), and unchanged (n = 15) testing rates. No difference was found across subgroups in costs, length of stay, 30-day ED revisit, or readmission rates. Comparing resource utilization trends over time provides important insights into achievable rates of testing reduction.

Phlebotomy-free days in children hospitalized with common infections and their association with clinical outcomes

BACKGROUND

Phlebotomy for hospitalized children has consequences (e.g., pain, iatrogenic anemia), and unnecessary testing is a modifiable source of waste in healthcare. Days without blood draws or phlebotomy-free days (PFDs) has the potential to serve as a hospital quality measure.

OBJECTIVE

To describe: (1) the frequency of PFDs in children hospitalized with common infections and (2) the association of PFDs with clinical outcomes.

DESIGN, SETTINGS AND PARTICIPANTS

We performed a cross-sectional study of children hospitalized 2018-2019 with common infections at 38 hospitals using the Pediatric Health Information System database. We included infectious All Patients Refined Diagnosis Related Groups with a median length of stay (LOS) >2 days. We excluded patients with medical complexity, interhospital transfers, those receiving intensive care, and in-hospital mortality.

MAIN OUTCOME AND MEASURES

We defined PFDs as hospital days (midnight to midnight) without laboratory blood testing and measured the proportion of PFDs divided by total hospital LOS (PFD ratio) for each condition and hospital. Higher PFD ratios signify more days without phlebotomy. Hospitals were grouped into low, moderate, and high average PFD ratios. Adjusted outcomes (LOS, costs, and readmissions) were compared across groups.

RESULTS

We identified 126,135 encounters. Bronchiolitis (0.78) and pneumonia (0.54) had the highest PFD ratios (most PFDs), while osteoarticular infections (0.28) and gastroenteritis (0.30) had the lowest PFD ratios. There were no differences in adjusted clinical outcomes across PFD ratio groups. Among children hospitalized with common infections, PFD ratios varied across conditions and hospitals, with no association with outcomes. Our data suggest overuse of phlebotomy and opportunities to improve the care of hospitalized children.

Clinical Decision Support Principles for Quality Improvement and Research

Pediatric hospitalists frequently interact with clinical decision support (CDS) tools in patient care and use these tools for quality improvement or research. In this method/ology paper, we provide an introduction and practical approach to developing and evaluating CDS tools within the electronic health record. First, we define CDS and describe the types of CDS interventions that exist. We then outline a stepwise approach to CDS development, which begins with defining the problem and understanding the system. We present a framework for metric development and then describe tools that can be used for CDS design (eg, 5 Rights of CDS, "10 commandments," usability heuristics, human-centered design) and testing (eg, validation, simulation, usability testing). We review approaches to evaluating CDS tools, which range from randomized studies to traditional quality improvement methods. Lastly, we discuss practical considerations for implementing CDS, including the assessment of a project team's skills and an organization's information technology resources.

Usability Testing of Situation Awareness Clinical Decision Support in the Intensive Care Unit

OBJECTIVE

 Our objective was to evaluate the usability of an automated clinical decision support (CDS) tool previously implemented in the pediatric intensive care unit (PICU) to promote shared situation awareness among the medical team to prevent serious safety events within children's hospitals.

METHODS

 We conducted a mixed-methods usability evaluation of a CDS tool in a PICU at a large, urban, quaternary, free-standing children's hospital in the Midwest. Quantitative assessment was done using the system usability scale (SUS), while qualitative assessment involved think-aloud usability testing. The SUS was scored according to survey guidelines. For think-aloud testing, task times were calculated, and means and standard deviations were determined, stratified by role. Qualitative feedback from participants and moderator observations were summarized.

RESULTS

 Fifty-one PICU staff members, including physicians, advanced practice providers, nurses, and respiratory therapists, completed the SUS, while ten participants underwent think-aloud usability testing. The overall median usability score was 87.5 (interquartile range: 80-95), with over 96% rating the tool's usability as "good" or "excellent." Task completion times ranged from 2 to 92 seconds, with the quickest completion for reviewing high-risk criteria and the slowest for adding to high-risk criteria. Observations and participant responses from think-aloud testing highlighted positive aspects of learnability and clear display of complex information that is easily accessed, as well as opportunities for improvement in tool integration into clinical workflows.

CONCLUSION

 The PICU Warning Tool demonstrates good usability in the critical care setting. This study demonstrates the value of postimplementation usability testing in identifying opportunities for continued improvement of CDS tools.

The Chief Residency in U.S. and Canadian Graduate Medical Education: A Scoping Review

PHENOMENON

Despite the nearly universal presence of chief residents within U.S. and Canadian residency programs and their critical importance in graduate medical education, to our knowledge, a comprehensive synthesis of publications about chief residency does not exist. An understanding of the current state of the literature can be helpful to program leadership to make evidence-based improvements to the chief residency and for medical education researchers to recognize and fill gaps in the literature.

APPROACH

We performed a scoping review of the literature about chief residency. We searched OVID Medline, PsycINFO, ERIC, and Web of Science databases through January 2023 for publications about chief residency. We included publications addressing chief residency in ACGME specialties in the U.S. and Canada and only those using the term "chief resident" to refer to additional responsibilities beyond the typical residency training. We excluded publications using chief residents as a convenience sample. We performed a topic analysis to identify common topics among studies.

FINDINGS

We identified 2,064 publications. We performed title and abstract screening on 1,306 and full text review on 208, resulting in 146 included studies. Roughly half of the publications represented the specialties of Internal Medicine (n = 37, 25.3%) and Psychiatry (n = 30, 20.5%). Topic analysis revealed six major topics: (1) selection of chief residents (2) qualities of chief residents (3) training of chief residents (4) roles of chief residents (5) benefits/challenges of chief residency (6) outcomes after chief residency.

INSIGHTS

After reviewing our topic analysis, we identified three key areas warranting increased attention with opportunity for future study: (1) addressing equity and bias in chief resident selection (2) establishment of structured expectations, mentorship, and training of chief residents and (3) increased attention to chief resident experience and career development, including potential downsides of the role.

Epidemiology and Severity of Illness of MIS-C and Kawasaki Disease During the COVID-19 Pandemic

BACKGROUND AND OBJECTIVES

Multisystem inflammatory syndrome in children (MIS-C) is a novel, severe condition following severe acute respiratory syndrome coronavirus 2 infection. Large epidemiologic studies comparing MIS-C to Kawasaki disease (KD) and evaluating the evolving epidemiology of MIS-C over time are lacking. We sought to understand the illness severity of MIS-C compared with KD and evaluate changes in MIS-C illness severity over time during the coronavirus disease 2019 pandemic compared with KD.

METHODS

We included hospitalizations of children with MIS-C and KD from April 2020 to May 2022 from the Pediatric Health Information System administrative database. Our primary outcome measure was the presence of shock, defined as the use of vasoactive/inotropic cardiac support or extracorporeal membrane oxygenation. We examined the volume of MIS-C and KD hospitalizations and the proportion of hospitalizations with shock over time using 2-week intervals. We compared the proportion of hospitalizations with shock in MIS-C and KD patients over time using generalized estimating equations adjusting for hospital clustering and age, with time as a fixed effect.

RESULTS

We identified 4868 hospitalizations for MIS-C and 2387 hospitalizations for KD. There was a higher proportion of hospitalizations with shock in MIS-C compared with KD (38.7% vs 5.1%). In our models with time as a fixed effect, we observed a significant decrease in the odds of shock over time in MIS-C patients (odds ratio 0.98, P < .001) but not in KD patients (odds ratio 1.00, P = .062).

CONCLUSIONS

We provide further evidence that MIS-C is a distinct condition from KD. MIS-C was a source of lower morbidity as the pandemic progressed.

The Autonomy Toolbox: A Multicenter Collaborative to Promote Resident Autonomy

OBJECTIVES

Autonomy is necessary for resident professional development and well-being. A recent focus on patient safety has increased supervision and decreased trainee autonomy. Few validated interventions exist to improve resident autonomy. We aimed to use quality improvement methods to increase our autonomy metric, the Resident Autonomy Score (RAS), by 25% within 1 year and sustain for 6 months.

METHODS

We developed a bundled-intervention approach to improve senior resident (SR) perception of autonomy on Pediatric Hospital Medicine (PHM) services at 5 academic children's hospitals. We surveyed SR and PHM faculty perceptions of autonomy and targeted interventions toward areas with the highest discordance. Interventions included SR and faculty development, expectation-setting huddles, and SR independent rounding. We developed a Resident Autonomy Score (RAS) index to track SR perceptions over time.

RESULTS

Forty-six percent of SRs and 59% of PHM faculty completed the needs assessment survey querying how often SRs were afforded opportunities to provide autonomous medical care. Faculty and SR ratings were discordant in these domains: SR input in medical decisions, SR autonomous decision-making in straightforward cases, follow-through on SR plans, faculty feedback, SR as team leader, and level of attending oversight. The RAS increased by 19% (3.67 to 4.36) 1 month after SR and faculty professional development and before expectation-setting and independent rounding. This increase was sustained throughout the 18-month study period.

CONCLUSIONS

SRs and faculty perceive discordant levels of SR autonomy. We created an adaptable autonomy toolbox that led to sustained improvement in perception of SR autonomy.

Identifying and Validating Pediatric Hospitalizations for MIS-C Through Administrative Data

BACKGROUND

Individual children's hospitals care for a small number of patients with multisystem inflammatory syndrome in children (MIS-C). Administrative databases offer an opportunity to conduct generalizable research; however, identifying patients with MIS-C is challenging.

METHODS

We developed and validated algorithms to identify MIS-C hospitalizations in administrative databases. We developed 10 approaches using diagnostic codes and medication billing data and applied them to the Pediatric Health Information System from January 2020 to August 2021. We reviewed medical records at 7 geographically diverse hospitals to compare potential cases of MIS-C identified by algorithms to each participating hospital's list of patients with MIS-C (used for public health reporting).

RESULTS

The sites had 245 hospitalizations for MIS-C in 2020 and 358 additional MIS-C hospitalizations through August 2021. One algorithm for the identification of cases in 2020 had a sensitivity of 82%, a low false positive rate of 22%, and a positive predictive value (PPV) of 78%. For hospitalizations in 2021, the sensitivity of the MIS-C diagnosis code was 98% with 84% PPV.

CONCLUSION

We developed high-sensitivity algorithms to use for epidemiologic research and high-PPV algorithms for comparative effectiveness research. Accurate algorithms to identify MIS-C hospitalizations can facilitate important research for understanding this novel entity as it evolves during new waves.

Variation in stool testing for children with acute gastrointestinal infections

BACKGROUND AND OBJECTIVE

Children with gastrointestinal infections often require acute care.The objectives of this study were to describe variations in patterns of stool testing across children's hospitals and determine whether such variation was associated with utilization outcomes.

DESIGN, SETTINGS AND PARTICIPANTS

We performed a multicenter, cross-sectional study using the Pediatric Health Information System (PHIS) database. We identified stool testing (multiplex polymerase chain reaction [PCR], stool culture, ova and parasite, Clostridioides difficile, and other individual stool bacterial or viral tests) in children diagnosed with acute gastrointestinal infections.

MAIN OUTCOME AND MEASURES

We calculated the overall testing rates and hospital-level stool testing rates, stratified by setting (emergency department [ED]-only vs. hospitalized). We stratified individual hospitals into low, moderate, or high testing institutions. Generalized estimating equations were then used to examine the association of hospital testing groups and outcomes, specifically, length of stay (LOS), costs, and revisit rates.

RESULTS

We identified 498,751 ED-only and 40,003 encounters for hospitalized children from 2016 to 2020. Compared to ED-only encounters, stool studies were obtained with increased frequency among encounters for hospitalized children (ED-only: 0.1%-2.3%; Hospitalized: 1.5%-13.8%, all p < 0.001). We observed substantial variation in stool testing rates across hospitals, particularly during encounters for hospitalized children (e.g., rates of multiplex PCRs ranged from 0% to 16.8% for ED-only and 0% to 65.0% for hospitalized). There were no statistically significant differences in outcomes among low, moderate, or high testing institutions in adjusted models.

CONCLUSIONS

Children with acute gastrointestinal infections experience substantial variation in stool testing within and across hospitals, with no difference in utilization outcomes. These findings highlight the need for guidelines to address diagnostic stewardship.

Variation in bacterial pneumonia diagnoses and outcomes among children hospitalized with lower respiratory tract infections

BACKGROUND

Current diagnostics do not permit reliable differentiation of bacterial from viral causes of lower respiratory tract infection (LRTI), which may lead to over-treatment with antibiotics for possible bacterial community-acquired pneumonia (CAP).

OBJECTIVES

We sought to describe variation in the diagnosis and treatment of bacterial CAP among children hospitalized with LRTIs and determine the association between CAP diagnosis and outcomes.

DESIGN, SETTING AND PARTICIPANTS

This multicenter cross-sectional study included children hospitalized between 2017 and 2019 with LRTIs at 42 children's hospitals.

MAIN OUTCOME AND METHODS

We calculated the proportion of children with LRTIs who were diagnosed with and treated for bacterial CAP. After adjusting for confounders, hospitals were grouped into high, moderate, and low CAP diagnosis groups. Multivariable regression was used to examine the association between high and low CAP diagnosis groups and outcomes.

RESULTS

We identified 66,581 patients hospitalized with LRTIs and observed substantial variation across hospitals in the proportion diagnosed with and treated for bacterial CAP (median 27%, range 12%-42%). Compared with low CAP diagnosing hospitals, high diagnosing hospitals had higher rates of CAP-related revisits (0.6% [95% confidence interval: 0.5, 0.7] vs. 0.4% [0.4, 0.5], p = .04), chest radiographs (58% [53, 62] vs. 46% [41, 51], p = .02), and blood tests (43% [33, 53] vs. 26% [19, 35], p = .046). There were no significant differences in length of stay, all-cause revisits or readmissions, CAP-related readmissions, or costs.

CONCLUSION

There was wide variation across hospitals in the proportion of children with LRTIs who were treated for bacterial CAP. The lack of meaningful differences in clinical outcomes among hospitals suggests that some institutions may over-diagnose and overtreat bacterial CAP.

Establishment of achievable benchmarks of care in the neurodiagnostic evaluation of simple febrile seizures

BACKGROUND

Current guidelines recommend against neurodiagnostic testing for the evaluation of simple febrile seizures.

OBJECTIVES

(1) Assess overall and institutional rates of neurodiagnostic testing and (2) establish achievable benchmarks of care (ABCs) for children evaluated for simple febrile seizures at children's hospitals.

DESIGN, SETTING, AND PARTICIPANTS

Cross-sectional study of children 6 months to 5 years evaluated in the emergency department (ED) 2016-2019 with simple febrile seizures at 38 children's hospitals in Pediatric Health Information System database. We excluded children with epilepsy, complex febrile seizures, complex chronic conditions, and intensive care.

OUTCOME MEASURES

Proportions of children who received neuroimaging, electroencephalogram (EEG), or lumbar puncture (LP) and rates of hospitalization for study cohort and individual hospitals. Hospital-specific outcomes were adjusted for patient demographics and severity of illness. We utilized hospital-specific values for each measure to calculate ABCs.

RESULTS

We identified 51,015 encounters. Among the study cohort 821 (1.6%) children had neuroimaging, 554 (1.1%) EEG, 314 (0.6%) LP, and 2023 (4.0%) were hospitalized. Neurodiagnostic testing rates varied across hospitals: neuroimaging 0.4%-6.7%, EEG 0%-8.2%, LP 0%-12.7% in patients <1-year old and 0%-3.1% in patients ≥1 year. Hospitalization rate ranged from 0%-14.5%. Measured outcomes were higher among hospitalized versus ED-only patients: neuroimaging 15.3% versus 1.0%, EEG% 24.7 versus 0.1% (p < .001). Calculated ABCs were 0.6% for neuroimaging, 0.1% EEG, 0% LP, and 1.0% hospitalization.

CONCLUSIONS

Rates of neurodiagnostic testing and hospitalization for simple febrile seizures were low but varied across hospitals. Calculated ABCs were 0%-1% for all measures, demonstrating that adherence to current guidelines is attainable.

Trends and Variation in Length of Stay Among Hospitalized Febrile Infants ≤60 Days Old

OBJECTIVES

Researchers in recent studies suggest that hospitalized febrile infants aged ≤60 days may be safely discharged if bacterial cultures are negative after 24-36 hours of incubation. We aimed to describe trends and variation in length of stay (LOS) for hospitalized febrile infants across children's hospitals.

METHODS

We conducted a multicenter retrospective cohort study of febrile infants aged ≤60 days hospitalized from 2016 to 2019 at 39 hospitals in the Pediatric Health Information System database. We excluded infants with complex chronic conditions, bacterial infections, lower respiratory tract viral infections, and those who required ICU admission. The primary outcomes were trends in LOS overall and for individual hospitals, adjusted for patient demographics and clinical characteristics. We also evaluated the hospital-level association between LOS and 30-day readmissions.

RESULTS

We identified 11 868 eligible febrile infant encounters. The adjusted mean LOS for the study cohort decreased from 44.0 hours in 2016 to 41.9 hours in 2019 (P < .001). There was substantial variation in adjusted mean LOS across children's hospitals, range 33.5-77.9 hours in 2016 and 30.4-100.0 hours in 2019. The change from 2016 to 2019 in adjusted mean LOS across individual hospitals also varied widely (-23.9 to +26.7 hours; median change -1.8 hours, interquartile range: -5.4 to 0.3). There was no association between hospital-level LOS and readmission rates (P = .70).

CONCLUSIONS

The LOS for hospitalized febrile infants decreased marginally between 2016 and 2019, although overall LOS and change in LOS varied substantially across children's hospitals. Continued quality improvement efforts are needed to reduce LOS for hospitalized febrile infants.

Short-term outcomes in children following emergency department visits for minor injuries sustained at home

Background

Minor injuries are very common in the pediatric population and often occur in the home environment. Despite its prevalence, little is known about outcomes in children following minor injury at home. Understanding the impact of these injuries on children and their families is important for treatment, prevention, and policy. The objectives of our study were (1) To describe the distribution of short-term outcomes following pediatric minor injuries sustained at home and (2) To explore the relationship of injury type and patient and household demographics with these outcomes.

Methods

Children (n = 102) aged 0–7 years with a minor injury sustained at home were recruited in an urban pediatric emergency department as part of the Child Housing Assessment for a Safer Environment (CHASE) observational study. Each patient had a home visit following the emergency department visit, where five parent-reported outcomes were assessed. Relationships were explored with logistic regression.

Results

The most common type of injury was soft tissue (57.8 %). 13.2 % of children experienced ≥ 7 days of pain, 21.6 % experienced ≥ 7 days of abnormal activity, 8.9 % missed ≥ 5 days of school, 17.8 % of families experienced ≥ 7 days of disruption, and 9.1 % of parents missed ≥ 5 days of work. Families reported a total of 120 missed school days and 120 missed work days. Children who sustained a burn had higher odds of experiencing pain (OR 6.97), abnormal activity (OR 8.01), and missing school (OR 8.71). The parents of children who sustained a burn had higher odds of missing work (OR 14.97).

Conclusions

Families of children suffering a minor injury at home reported prolonged pain and changes in activity as well as significant school and work loss. In this cohort, burns were more likely than other minor injuries to have these negative short-term outcomes reported and represent an important target for interventions. The impact of these injuries on missed school and disruption of parental work warrants further consideration.

Targeted Education Across Clinical Settings Improves Adherence to Evidence-Based Interventions for Bronchiolitis

Bronchiolitis remains a leading cause of hospitalization of infants. Despite evidence-based recommendations, wide variation in practice remains. A pre-post educational intervention was implemented to improve adherence to bronchiolitis guidelines in emergency and inpatient settings. Among children meeting inclusion criteria (136 pre-intervention, 185 post-intervention), emergency department (ED) bronchodilator use decreased by 64% (P < .001). Steroid use decreased by 71% (P = .002). There was no difference in viral testing, antibiotic use, or chest radiograph acquisition. No differences were seen in the inpatient setting. There was no difference in rate of intensive care unit transfer or length of stay. Post-intervention, children were less likely to receive a bronchodilator in the ED (odds ratio [OR] = 0.15, P < .001). Children with a family history of asthma were more likely to receive a bronchodilator in the ED (OR = 4.25, P < .001). Targeted education across settings contributed to reducing bronchodilator use in the ED. Family history appeared to influence medical decision making.

Divergent transcriptional response to thermal stress by Anopheles gambiae larvae carrying alternative arrangements of inversion 2La

The African malaria mosquito Anopheles gambiae is polymorphic for chromosomal inversion 2La, whose frequency strongly correlates with degree of aridity across environmental gradients. Recent physiological studies have associated 2La with resistance to desiccation in adults and thermal stress in larvae, consistent with its proposed role in aridity tolerance. However, the genetic basis of these traits remains unknown. To identify genes that could be involved in the differential response to thermal stress, we compared global gene expression profiles of heat-hardened 2La or 2L+(a) larvae at three time points, for up to eight hours following exposure to the heat stress. Treatment and control time series, replicated four times, revealed a common and massive induction of a core set of heat-shock genes regardless of 2La orientation. However, clear differences between the 2La and 2L+(a) arrangements emerged at the earliest (0.25 h) time point, in the intensity and nature of the stress response. Overall, 2La was associated with the more aggressive response: larger numbers of genes were heat responsive and up-regulated. Transcriptionally induced genes were enriched for functions related to ubiquitin-proteasomal degradation, chaperoning and energy metabolism. The more muted transcriptional response of 2L+(a) was largely repressive, including genes involved in proteolysis and energy metabolism. These results may help explain the maintenance of the 2La inversion polymorphism in An. gambiae, as the survival benefits offered by high thermal sensitivity in harsh climates could be offset by the metabolic costs of such a drastic response in more equable climates.

An evaluation of simultaneously administered free and intrinsic factor bound radioactive cyanocobalamin in the diagnosis of pernicious anaemia in the elderly

The definitive diagnosis of pernicious anaemia (PA) in the elderly is by no means always straightforward, particularly when inappropriate medication has been introduced before the institution of specific investigatory procedures. A detailed haematological study was carried out on 301 patients aged 60-95 with a serum B(12) concentration at the laboratory's lower level of normal of 150 ng per litre (Euglena gracilis assay). The diagnosis of PA was based on strict predetermined haematological criteria. All patients were subsequently studied by the simultaneous oral administration of the dual isotopes (57)Co-labelled B(12) bound to intrinsic factor and free (58)Co-labelled B(12) (Dicopac test), and urine was collected over 24 hours after an intramuscular dose of 1 mg nonradioactive B(12) for estimation of the (57)Co/(58)Co B(12) ratio; 255 patients satisfied all criteria for final analysis. The Radiochemical Centre, Amersham suggests an upper limit of the normal range for the (57)Co/(58)Co ratio of 1.3 with a lower limit for PA of 2.0. We were unable to show a sharp borderline in the (57)Co/(58)Co B(12) ratio between those patients shown by other criteria to have PA and those who do not have PA; 34% of the 71 established patients had a ratio below 2.0. From our series a ratio borderline drawn at 1.4 gave only one false negative (1.4% of the PA group). Of the 175 non-PA cases, nine (5%) gave false positive results; four of these had (58)Co excretion levels high enough to make misdiagnosis unlikely. In a proportion of patients the (57)Co/(58)Co B(12) ratio was estimated at regular intervals for 36-hour periods. Maximum accuracy of isotope measurement on a single specimen was obtained 8-20 hours after isotope dosing. The Dicopac investigation is a useful simple screening test in the differential diagnosis of patients with a megaloblastic bone marrow and combined low serum B(12) and folate concentrations. When carried out by the standard technique, the degree of discrimination between normal and abnormal ratios is of limited diagnostic significance in one-third of patients.