Single-Cell Transcriptomic Analysis of Kaposi Sarcoma

Kaposi Sarcoma (KS) is a complex tumor caused by KS-associated herpesvirus 8 (KSHV). Histological analysis reveals a mixture of "spindle cells", vascular-like spaces, extravasated erythrocytes, and immune cells. In order to elucidate the infected and uninfected cell types in KS tumors, we examined skin and blood samples from twelve subjects by single cell RNA sequence analyses. Two populations of KSHV-infected cells were identified, one of which represented a proliferative fraction of lymphatic endothelial cells, and the second represented an angiogenic population of vascular endothelial tip cells. Both infected clusters contained cells expressing lytic and latent KSHV genes. Novel cellular biomarkers were identified in the KSHV infected cells, including the sodium channel SCN9A. The number of KSHV positive tumor cells was found to be in the 6% range in HIV-associated KS, correlated inversely with tumor-infiltrating immune cells, and was reduced in biopsies from HIV-negative individuals. T-cell receptor clones were expanded in KS tumors and blood, although in differing magnitudes. Changes in cellular composition in KS tumors were identified in subjects treated with antiretroviral therapy alone, or immunotherapy. These studies demonstrate the feasibility of single cell analyses to identify prognostic and predictive biomarkers.

Author Summary

Kaposi sarcoma (KS) is a malignancy caused by the KS-associated herpesvirus (KSHV) that causes skin lesions, and may also be found in lymph nodes, lungs, gastrointestinal tract, and other organs in immunosuppressed individuals more commonly than immunocompetent subjects. The current study examined gene expression in single cells from the tumor and blood of these subjects, and identified the characteristics of the complex mixtures of cells in the tumor. This method also identified differences in KSHV gene expression in different cell types and associated cellular genes expressed in KSHV infected cells. In addition, changes in the cellular composition could be elucidated with therapeutic interventions.

Racial and Ethnic Disparities in Length of Stay for Common Pediatric Diagnoses: Trends From 2016 to 2019

BACKGROUND AND OBJECTIVES

Inequities in pediatric illness include unequal treatment and outcomes for children of historically marginalized races/ethnicities. Length of stay (LOS) is used to assess health care quality and is associated with higher costs/complications. Studies show LOS disparities for Black and Hispanic children in specific diagnoses, but it is unclear how broadly they exist or how they change over time. We examined the association between race/ethnicity and LOS longitudinally for the most common pediatric inpatient diagnoses.

METHODS

We used the 2016 and 2019 Kids' Inpatient Databases. The 10 most frequent diagnoses in 2016 were determined. For each diagnosis in each year, we assessed the association between race and LOS by fitting a generalized linear mixed effects model with a negative binomial distribution, accounting for clustering and confounding. Using descriptive statistics, we compared associations between the 2 years for trends over time.

RESULTS

Our analysis included >450 000 admissions and revealed significantly longer LOS for Black, Hispanic, and/or Asian American or Pacific Islander, Native American, and other children in 8 of the 10 diagnoses in 2016, with mixed changes over time. Three new disparities emerged in 2019. The largest disparities were for Black children in most diagnoses.

CONCLUSIONS

Kids' Inpatient Database data showed longer LOS for children of historically marginalized race/ethnicity with common pediatric inpatient diagnoses, which largely persisted from 2016 to 2019. There is no plausible biological explanation for these findings, and inequities in social needs, access to care, and quality of care likely contribute. Future directions include further study to understand and address contributing factors.

Reviewer Feedback for Abstract Submissions to the Pediatric Academic Societies Meeting: A Pilot Project

PURPOSE

To describe and evaluate a pilot project to provide reviewer comments to authors who submitted abstracts to the Hospital-based medicine topic area for the Pediatric Academic Societies (PAS) 2021 annual meeting METHODS: Abstract reviewers were encouraged via email to include reviewer comments for authors in their abstract reviews. Unedited comments were emailed to authors shortly after the abstract decision notifications were sent. We quantified the number of reviewers who commented per abstract. Additionally, we surveyed authors and reviewers to evaluate the perceived impact of the pilot project.

RESULTS

For 123 abstracts submitted to the Hospital-based medicine topic area, every abstract received comments from at least one reviewer, and a median (IQR) of 4 (3-5) reviewers commented per abstract. The response rates for the author and reviewer surveys were 61/114 (54%) and 54/84 (64%), respectively, and both groups of respondents generally favored the pilot program. The majority of authors (59%) made changes to their project based on the feedback provided and 96% reported that they would like to continue to receive reviewer feedback for future PAS abstract submissions. Reviewers reported spending a mean of 11 minutes reviewing each abstract. Most (85%) felt that they spent the same or slightly more (1%-25%) time reviewing than in prior years. Multiple open-ended comments were provided, largely positive.

CONCLUSION

A pilot program to incorporate reviewer feedback into abstract decision notification for a large national research meeting was successful. This approach should be considered for future meetings to enhance this integral component of academic development.

Adult T-Cell Leukemia-Lymphoma Presenting Concurrently with Myelopathy

Human T-cell leukemia virus type 1 (HTLV-1) is an oncogenic retrovirus. Of the approximate ten to twenty million people currently infected worldwide, 4-9% of infected individuals develop adult T-cell leukemia/lymphoma (ATLL) or HTLV-associated myelopathy/tropical spastic paresis (HAM/TSP) in their lifetime. The current report is based on a patient who presented concurrently with CD30+ lymphoma subtype ATLL and HAM/TSP. The patient's ATLL responded to brentuximab-vedotin-based chemotherapy; however, HAM/TSP did not improve. The patient's peripheral blood mononuclear cells were cultured and injected into immunodeficient mice, and the mice developed massive organ involvement and chronic lymphocytic leukemia-subtype ATLL. This case study is novel in the findings of concurrent development of ATLL and HAM/TSP, the response to brentuximab-vedotin chemotherapy, and the use HTLV-1 helix basic zipper protein-targeted probe for RNAscope for diagnosis.

Guidance for Structuring a Pediatric Intermediate Care Unit

The purpose of this policy statement is to update the 2004 American Academy of Pediatrics clinical report and provide enhanced guidance for institutions, administrators, and providers in the development and operation of a pediatric intermediate care unit (IMCU). Since 2004, there have been significant advances in pediatric medical, surgical, and critical care that have resulted in an evolution in the acuity and complexity of children potentially requiring IMCU admission. A group of 9 clinical experts in pediatric critical care, hospital medicine, intermediate care, and surgery developed a consensus on priority topics requiring updates, reviewed the relevant evidence, and, through a series of virtual meetings, developed the document. The intended audience of this policy statement is broad and includes pediatric critical care professionals, pediatric hospitalists, pediatric surgeons, other pediatric medical and surgical subspecialists, general pediatricians, nurses, social workers, care coordinators, hospital administrators, health care funders, and policymakers, primarily in resource-rich settings. Key priority topics were delineation of core principles for an IMCU, clarification of target populations, staffing recommendations, and payment.

Availability of Pediatric Inpatient Services in the United States

OBJECTIVES

We sought to evaluate trends in pediatric inpatient unit capacity and access and to measure pediatric inpatient unit closures across the United States.

METHODS

We performed a retrospective study of 4720 US hospitals using the 2008-2018 American Hospital Association survey. We used linear regression to describe trends in pediatric inpatient unit and PICU capacity. We compared trends in pediatric inpatient days and bed counts by state. We examined changes in access to care by calculating distance to the nearest pediatric inpatient services by census block group. We analyzed hospital characteristics associated with pediatric inpatient unit closure in a survival model.

RESULTS

Pediatric inpatient units decreased by 19.1% (34 units per year; 95% confidence interval [CI] 31 to 37), and pediatric inpatient unit beds decreased by 11.8% (407 beds per year; 95% CI 347 to 468). PICU beds increased by 16.0% (66.9 beds per year; 95% CI 53 to 81), primarily at children's hospitals. Rural areas experienced steeper proportional declines in pediatric inpatient unit beds (-26.1% vs -10.0%). Most states experienced decreases in both pediatric inpatient unit beds (median state -18.5%) and pediatric inpatient days (median state -10.0%). Nearly one-quarter of US children experienced an increase in distance to their nearest pediatric inpatient unit. Low-volume pediatric units and those without an associated PICU were at highest risk of closing.

CONCLUSIONS

Pediatric inpatient unit capacity is decreasing in the United States. Access to inpatient care is declining for many children, particularly those in rural areas. PICU beds are increasing, primarily at large children's hospitals. Policy and surge planning improvements may be needed to mitigate the effects of these changes.

Targeting NF-κB with Nanotherapy in a Mouse Model of Adult T-Cell Leukemia/Lymphoma

Adult T-cell leukemia/lymphoma (ATLL) is an aggressive, clonal malignancy of mature T cells caused by human T-cell leukemia virus type 1. Although it is a rare tumor type, it serves as an excellent model of a virus driven process that transforms cells and engenders a highly malignant tumor that is extraordinarily difficult to treat. The viral transcriptional transactivator (Tax) in the HTLV-1 genome directly promotes tumorigenesis, and Tax-induced oncogenesis depends on its ability to constitutively activate NF-κB signaling. Accordingly, we developed and evaluated a nano-delivery system that simultaneously inhibits both canonical (p65) and noncanonical (p100) NF-κB signaling pathways locally in tumors after systemic administration. Our results demonstrate that siRNA is delivered rapidly to ATLL tumors after either i.p. or i.v. injection. The siRNA treatment significantly reduced both p65 and p100 mRNA and protein expression. Anti-NF-κB nanotherapy significantly inhibited tumor growth in two distinct tumor models in mice: a spontaneous Tax-driven tumor model, and a Tax tumor cell transplant model. Moreover, siRNA nanotherapy sensitized late-stage ATLL tumors to the conventional chemotherapeutic agent etoposide, indicating a pleiotropic benefit for localized siRNA nanotherapeutics.

Epigenomic regulation of human T-cell leukemia virus by chromatin-insulator CTCF

Human T-cell leukemia virus type 1 (HTLV-1) is a retrovirus that causes an aggressive T-cell malignancy and a variety of inflammatory conditions. The integrated provirus includes a single binding site for the epigenomic insulator, CCCTC-binding protein (CTCF), but its function remains unclear. In the current study, a mutant virus was examined that eliminates the CTCF-binding site. The mutation did not disrupt the kinetics and levels of virus gene expression, or establishment of or reactivation from latency. However, the mutation disrupted the epigenetic barrier function, resulting in enhanced DNA CpG methylation downstream of the CTCF binding site on both strands of the integrated provirus and H3K4Me3, H3K36Me3, and H3K27Me3 chromatin modifications both up- and downstream of the site. A majority of clonal cell lines infected with wild type HTLV-1 exhibited increased plus strand gene expression with CTCF knockdown, while expression in mutant HTLV-1 clonal lines was unaffected. These findings indicate that CTCF binding regulates HTLV-1 gene expression, DNA and histone methylation in an integration site dependent fashion.

Human T-cell leukemia virus type 1 (HTLV-1) is a cause of leukemia and lymphoma as well as several inflammatory medical disorders. The virus integrates in the host cell DNA, and it has a single binding site for a protein designated CTCF. This protein is important in the regulation of many DNA viruses, as well as many properties of normal and malignant cells. In order to define the role of CTCF binding to HTLV, we analyzed a mutant virus lacking the binding site. We found that this mutation variably affected gene expression, DNA and histone modification, suggesting a key role in regulation of virus replication in infected cells.

The Future of Inpatient Community Hospital Care: Is There One?

Community hospital inpatient pediatric programs face a variety of challenges including financial instability, variable censuses, difficulty maintaining qualified staff, and a lack of focus for the hospital. With the addition of new payment models, such as bundled payments and global budgets, along with a global pandemic, the future of community hospital pediatric inpatient care is uncertain at best. In this article we summarize the challenges, opportunities, and potential solutions to maintaining high-quality care for hospitalized children in community hospitals.

Interferon regulatory factor 4 as a therapeutic target in adult T-cell leukemia lymphoma

Background

Adult T-cell leukemia lymphoma (ATLL) is a chemotherapy-resistant malignancy with a median survival of less than one year that will afflict between one hundred thousand and one million individuals worldwide who are currently infected with human T-cell leukemia virus type 1. Recurrent somatic mutations in host genes have exposed the T-cell receptor pathway through nuclear factor κB to interferon regulatory factor 4 (IRF4) as an essential driver for this malignancy. We sought to determine if IRF4 represents a therapeutic target for ATLL and to identify downstream effectors and biomarkers of IRF4 signaling in vivo.

Results

ATLL cell lines, particularly Tax viral oncoprotein-negative cell lines, that most closely resemble ATLL in humans, were sensitive to dose- and time-dependent inhibition by a next-generation class of IRF4 antisense oligonucleotides (ASOs) that employ constrained ethyl residues that mediate RNase H-dependent RNA degradation. ATLL cell lines were also sensitive to lenalidomide, which repressed IRF4 expression. Both ASOs and lenalidomide inhibited ATLL proliferation in vitro and in vivo. To identify biomarkers of IRF4-mediated CD4 + T-cell expansion in vivo, transcriptomic analysis identified several genes that encode key regulators of ATLL, including interleukin 2 receptor subunits α and β, KIT ligand, cytotoxic T-lymphocyte-associated protein 4, and thymocyte selection-associated high mobility group protein TOX 2.

Conclusions

These data support the pursuit of IRF4 as a therapeutic target in ATLL with the use of either ASOs or lenalidomide.

Rapid progression of adult T-cell leukemia/lymphoma as tumor-infiltrating Tregs after PD-1 blockade

Immune checkpoint inhibitors are a powerful new tool in the treatment of cancer, with prolonged responses in multiple diseases, including hematologic malignancies, such as Hodgkin lymphoma. However, in a recent report, we demonstrated that the PD-1 inhibitor nivolumab led to rapid progression in patients with adult T-cell leukemia/lymphoma (ATLL) (NCT02631746). We obtained primary cells from these patients to determine the cause of this hyperprogression. Analyses of clonality, somatic mutations, and gene expression in the malignant cells confirmed the report of rapid clonal expansion after PD-1 blockade in these patients, revealed a previously unappreciated origin of these malignant cells, identified a novel connection between ATLL cells and tumor-resident regulatory T cells (Tregs), and exposed a tumor-suppressive role for PD-1 in ATLL. Identifying the mechanisms driving this alarming outcome in nivolumab-treated ATLL may be broadly informative for the growing problem of rapid progression with immune checkpoint therapies.

HTLV-1 viral oncogene HBZ drives bone destruction in adult T cell leukemia

Osteolytic bone lesions and hypercalcemia are common, serious complications in adult T cell leukemia/lymphoma (ATL), an aggressive T cell malignancy associated with human T cell leukemia virus type 1 (HTLV-1) infection. The HTLV-1 viral oncogene HBZ has been implicated in ATL tumorigenesis and bone loss. In this study, we evaluated the role of HBZ on ATL-associated bone destruction using HTLV-1 infection and disease progression mouse models. Humanized mice infected with HTLV-1 developed lymphoproliferative disease and continuous, progressive osteolytic bone lesions. HTLV-1 lacking HBZ displayed only modest delays to lymphoproliferative disease but significantly decreased disease-associated bone loss compared with HTLV-1-infected mice. Gene expression array of acute ATL patient samples demonstrated increased expression of RANKL, a critical regulator of osteoclasts. We found that HBZ regulated RANKL in a c-Fos-dependent manner. Treatment of HTLV-1-infected humanized mice with denosumab, a monoclonal antibody against human RANKL, alleviated bone loss. Using patient-derived xenografts from primary human ATL cells to induce lymphoproliferative disease, we also observed profound tumor-induced bone destruction and increased c-Fos and RANKL gene expression. Together, these data show the critical role of HBZ in driving ATL-associated bone loss through RANKL and identify denosumab as a potential treatment to prevent bone complications in ATL patients.

Changes in Urinary Tract Infection Hospitalizations Post 2011 Revised American Academy Pediatrics Guidelines

BACKGROUND

Multiple randomized trials over the past 2 decades have supported oral antimicrobial treatment for urinary tract infection (UTI), and the 2011 revised American Academy Pediatrics guidelines on the management of UTI provide further support for outpatient management. It is unknown whether practice patterns have changed as a result of these developments.

OBJECTIVE

To examine temporal trends in UTI hospitalizations between 1997 and 2012 as measured by the Kids' Inpatient Database.

DESIGN AND METHODS

The Kid's Inpatient Database was used to analyze trends in UTI hospitalizations between 1997 and 2012. This triennial database is publicly available through the Agency for Healthcare Research and Quality. Hospitalization volume for clinical classification software principal diagnosis category 159 Urinary tract infection was examined for trends across years by age. Changes in length of stay and charges corrected for inflation were also examined.

RESULTS

There were significantly fewer weighted UTI hospitalizations in 2012 compared with 1997 to 2009 (48 102 SE ± 1494 in 2009 vs 41 177 SE ± 1467 in 2012, P < .0001). The largest decrease was in 15- to 17-year-old (19.2%) and <1-year-old (18.6%) groups. The length of stay trended down consistently, but charges have increased despite correcting for consumer price index.

CONCLUSIONS

Year 2012 represents the first significant decrease in national hospitalization rates for UTI since 1997, a trend that may be explained by the accumulating evidence supporting outpatient management in addition to recommendations from the 2011 American Academy of Pediatrics UTI guidelines.

Physician's Role in Coordinating Care of Hospitalized Children

The hospitalization of a child is a stressful event for the child and family. The physician responsible for the admission has an important role in directing the care of the child, communicating with the child's providers (medical and primary caregivers), and advocating for the safety of the child during the hospitalization and transition out of the hospital. These challenges remain constant across the varied facilities in which children are hospitalized. The purpose of this revised clinical report is to update pediatricians about principles to improve the coordination of care and review expectations and practice.

HTLV-1 viral oncogene HBZ induces osteolytic bone disease in transgenic mice

Adult T-cell leukemia/lymphoma (ATL) is an aggressive T cell malignancy that occurs in HTLV-1 infected patients. Most ATL patients develop osteolytic lesions and hypercalcemia of malignancy, causing severe skeletal related complications and reduced overall survival. The HTLV-1 virus encodes 2 viral oncogenes, Tax and HBZ. Tax, a transcriptional activator, is critical to ATL development, and has been implicated in pathologic osteolysis. HBZ, HTLV-1 basic leucine zipper transcription factor, promotes tumor cell proliferation and disrupts Wnt pathway modulators; however, its role in ATL induced osteolytic bone loss is unknown. To determine if HBZ is sufficient for the development of bone loss, we established a transgenic Granzyme B HBZ (Gzmb-HBZ) mouse model. Lymphoproliferative disease including tumors, enlarged spleens and/or abnormal white cell counts developed in two-thirds of Gzmb-HBZ mice at 18 months. HBZ positive cells were detected in tumors, spleen and bone marrow. Importantly, pathologic bone loss and hypercalcemia were present at 18 months. Bone-acting factors were present in serum and RANKL, PTHrP and DKK1, key mediators of hypercalcemia and bone loss, were upregulated in Gzmb-HBZ T cells. These data demonstrate that Gzmb-HBZ mice model ATL bone disease and express factors that are current therapeutic targets for metastatic and bone resident tumors.

Changes in inpatient staffing following implementation of new residency work hours

BACKGROUND

In 2011, the Accreditation Council for Graduate Medical Education added additional resident work-hour restrictions that limited the number of hours residents could work, with increased emphasis on attending supervision.

OBJECTIVE

Our objective was to determine how residency programs have responded to residency work hours, specifically assessing residency night float systems and in-house attending physicians.

DESIGN

In May 2012, an electronic survey was sent to all US pediatric residency training programs via the Association of Pediatric Program Directors listserv with e-mail reminders to nonresponding programs. We analyzed data to assess the use of resident night float systems, admission caps, and attending physicians in-house at night.

RESULTS

Out of 198 programs contacted, 152 programs responded (77% response rate). Residency programs utilizing a night float system increased from 43% to 71% after new work hours were implemented. Overall use of resident admission caps did not change significantly. Twenty-three percent of programs increased the number of attending physicians in-house at night; 57% of those programs increased the number of pediatric hospitalist attendings, whereas 37% increased the number of pediatric intensivists. There is a trend toward increased pediatric hospitalist attending in-house 24/7 coverage. Of programs without 24/7 coverage, 26% plan to add coverage within 5 years. Only 12% of programs have no in-house attending coverage at night.

CONCLUSIONS

Although programs vary in their response to changes in residency work restrictions, they most commonly utilize night float systems and increased the amount of in-house attending coverage at night, especially pediatric hospitalist attendings. Many programs plan to add 24/7 pediatric hospitalist coverage within 5 years.

IL-15 deficient tax mice reveal a role for IL-1α in tumor immunity

IL-15 is recognized as a promising candidate for tumor immunotherapy and has been described as both a promoter of cancer and a promoter of anti-cancer immunity. IL-15 was discovered in cells transformed by HTLV-1, the etiologic agent of adult T cell leukemia/lymphoma (ATL) and the human retrovirus that carries the Tax oncogene. We have developed the TAX-LUC mouse model of ATL in which Tax expression drives both malignant transformation and luciferase expression, enabling non-invasive imaging of tumorigenesis in real time. To identify the role of IL-15 in spontaneous development of lymphoma in vivo, an IL-15^−/− TAX-LUC strain was developed and examined. The absence of IL-15 resulted in aggressive tumor growth and accelerated mortality and demonstrated that IL-15 was not required for Tax-mediated lymphoma but was essential for anti-tumor immunity. Further analysis revealed a unique transcriptional profile in tumor cells that arise in the absence of IL-15 that included a significant increase in the expression of IL-1α and IL-1α-regulated cytokines. Moreover, anti-IL-1α antibodies and an IL-1 receptor antagonist (Anakinra) were used to interrogate the potential of IL-1α targeted therapies in this model. Taken together, these findings identify IL-15 and IL-1α as therapeutic targets in lymphoma.

Pediatric hospitalists' influences on education and career plans

BACKGROUND

Pediatric hospitalist (PH) presence is rapidly increasing, yet little is known about pediatric resident exposure to hospitalists, or how this affects resident education/career decisions.

OBJECTIVES

To determine resident exposure to pediatric hospitalists; examine resident opinions regarding hospitalists' roles; examine resident opinion of hospital medicine career training needs; explore how resident exposure to hospitalists affects career choices.

METHODS

Survey of random sample of 300 residents from the American Academy of Pediatrics Section on Residents database.

RESULTS

Two-hundred seventy-nine pediatric residents surveyed; 120(43%) responded with variance by question; 90% work with hospitalists during residency. Of this national sample, 82% cite hospitalists as enhancing education. A majority (64%) believe pediatric hospitalists are better than primary care physicians at caring for complex inpatients; 28% felt PH provided better care for routine admissions. Over one-third surveyed are considering a career in Pediatric Hospital Medicine (PHM); 7% plan to enter the field upon graduation. Residents cited opportunities to participate in education, flexible hours, and better salaries as the top 3 reasons to become a hospitalist. Ten percent felt there was no difference between resident and hospitalist positions; 21% see PHM as a short-term job without long-term potential. Of residents entering Primary Care, a majority (59%) stated that the availability of hospitalists would positively influence their choice of a practice position; 7% said they were "less likely to choose to practice Primary Care Pediatrics because of hospitalists."

CONCLUSIONS

PH have a role in physician training. While PHM has become a career consideration for trainees, more work needs to be done to improve the perception of PHM as a viable long-term career.

Medical staff appointment and delineation of pediatric privileges in hospitals

The review and verification of credentials and the granting of clinical privileges are required of every hospital to ensure that members of the medical staff are competent and qualified to provide specified levels of patient care. The credentialing process involves the following: (1) assessment of the professional and personal background of each practitioner seeking privileges; (2) assignment of privileges appropriate for the clinician's training and experience; (3) ongoing monitoring of the professional activities of each staff member; and (4) periodic reappointment to the medical staff on the basis of objectively measured performance. We examine the essential elements of a credentials review for initial and renewed medical staff appointments along with suggested criteria for the delineation of clinical privileges. Sample forms for the delineation of privileges can be found on the American Academy of Pediatrics Committee on Hospital Care Web site (http://www.aap.org/visit/cmte19.htm). Because of differences among individual hospitals, no 1 method for credentialing is universally applicable. The medical staff of each hospital must, therefore, establish its own process based on the general principles reviewed in this report. The issues of medical staff membership and credentialing have become very complex, and institutions and medical staffs are vulnerable to legal action. Consequently, it is advisable for hospitals and medical staffs to obtain expert legal advice when medical staff bylaws are constructed or revised.

Pediatric hospital medicine: a strategic planning roundtable to chart the future

Given the growing field of Pediatric Hospital Medicine (PHM) and the need to define strategic direction, the Society of Hospital Medicine, the American Academy of Pediatrics, and the Academic Pediatric Association sponsored a roundtable to discuss the future of the field. Twenty-one leaders were invited plus a facilitator utilizing established health care strategic planning methods. A "vision statement" was developed. Specific initiatives in 4 domains (clinical practice, quality of care, research, and workforce) were identified that would advance PHM with a plan to complete each initiative. Review of the current issues demonstrated gaps between the current state of affairs and the full vision of the potential impact of PHM. Clinical initiatives were to develop an educational plan supporting the PHM Core Competencies and a clinical practice monitoring dashboard template. Quality initiatives included an environmental assessment of PHM participation on key committees, societies, and agencies to ensure appropriate PHM representation. Three QI collaboratives are underway. A Research Leadership Task Force was created and the Pediatric Research in Inpatient Settings (PRIS) network was refocused, defining a strategic framework for PRIS, and developing a funding strategy. Workforce initiatives were to develop a descriptive statement that can be used by any PHM physician, a communications tool describing "value added" of PHM; and a tool to assess career satisfaction among PHM physicians. We believe the Roundtable was successful in describing the current state of PHM and laying a course for the near future.

Inpatient staffing within pediatric residency programs: work hour restrictions and the evolving role of the pediatric hospitalist

OBJECTIVE

In October 2010, the Accreditation Council for Graduate Medical Education (ACGME) mandated new standards that will further restrict resident work hours. There is growing concern surrounding the impact these restrictions will have on the staffing of inpatient services. The objective of this study was to survey the landscape of pediatric resident coverage of noncritical care inpatient teaching services prior to the implementation of these guidelines. In addition, we sought to explore how changes in work hour restrictions might affect the role of pediatric hospitalists in training programs.

METHODS

In January 2010, an institutional review board (IRB)-approved electronic survey was sent to 196 US residency training programs via the Association of Pediatric Program Directors (APPD) listserve.

RESULTS

One hundred twenty responses were received representing 5201 pediatric residents. Of the programs that responded, 84% have hospitalists. At programs with hospitalists (n = 97), 24% have pediatric hospitalist attendings in-house at night. Nearly a quarter of responding programs (22%) reported having no attending physicians in-house at night. At the time of our survey, 31% of programs anticipated the addition of 24-hour in-house hospitalist coverage within the next 5 years. When the additional work hour restrictions are implemented, 70% of programs anticipated the need to add additional hospitalist coverage at night.

CONCLUSIONS

Significant variation exists in how pediatric teaching services provide overnight coverage. While hospitalists are prevalent in pediatric training programs (84% overall, 67% day only), their role in direct patient care during the overnight hours has been limited thus far. New work hour restrictions will promote the need for more hospitalists.

Utility of post-urinary tract infection imaging in patients with normal prenatal renal ultrasound

The American Academy of Pediatrics recommends renal ultrasound (RUS) and voiding cystourethrography (VCUG) for all infants after a first urinary tract infection (UTI). However, many congenital renal anomalies are identified by a prenatal US. At the present time, there are no data regarding the yield of post-UTI imaging among infants who have a documented normal prenatal US. We retrospectively reviewed the charts of all patients <1 year of age with a first UTI who had normal kidneys noted on prenatal US to determine the frequency of abnormal findings. Abnormal RUS and VCUG results were noted in 5.1% (24 of 471) and 20.4% (75 of 368) of infants, respectively. While the abnormal US rate is significantly less than what has been previously reported, the frequency of abnormal VCUGs is similar. These results suggest that a post-UTI RUS may not be needed if the prenatal US was normal. However, a VCUG continues to be indicated.

The ARF tumor suppressor regulates bone remodeling and osteosarcoma development in mice

The ARF tumor suppressor regulates p53 as well as basic developmental processes independent of p53, including osteoclast activation, by controlling ribosomal biogenesis. Here we provide evidence that ARF is a master regulator of bone remodeling and osteosarcoma (OS) development in mice. Arf^-/- mice displayed increased osteoblast (OB) and osteoclast (OC) activity with a significant net increase in trabecular bone volume. The long bones of Arf^-/- mice had increased expression of OB genes while Arf^-/- OB showed enhanced differentiation in vitro. Mice transgenic for the Tax oncogene develop lymphocytic tumors with associated osteolytic lesions, while Tax+Arf^-/- mice uniformly developed spontaneous OS by 7 months of age. Tax+Arf^-/- tumors were well differentiated OS characterized by an abundance of new bone with OC recruitment, expressed OB markers and displayed intact levels of p53 mRNA and reduced Rb transcript levels. Cell lines established from OS recapitulated characteristics of the primary tumor, including the expression of mature OB markers and ability to form mineralized tumors when transplanted. Loss of heterozygosity in OS tumors arising in Tax+Arf^+/- mice emphasized the necessity of ARF-loss in OS development. Hypothesizing that inhibition of ARF-regulated bone remodeling would repress development of OS, we demonstrated that treatment of Tax+Arf^-/- mice with zoledronic acid, a bisphosphonate inhibitor of OC activity and repressor of bone turnover, prevented or delayed the onset of OS. These data describe a novel role for ARF as a regulator of bone remodeling through effects on both OB and OC. Finally, these data underscore the potential of targeting bone remodeling as adjuvant therapy or in patients with genetic predispositions to prevent the development of OS.

Evaluating the performance of medical educators: a novel analysis tool to demonstrate the quality and impact of educational activities

PURPOSE

Traditional promotion standards rely heavily on quantification of research grants and publications in the curriculum vitae. The promotion and retention of educators is challenged by the lack of accepted standards to evaluate the depth, breadth, quality, and impact of educational activities. The authors sought to develop a practical analysis tool for the evaluation of educator portfolios (EPs), based on measurable outcomes that allow reproducible analysis of the quality and impact of educational activities.

METHOD

The authors, 10 veteran educators and an external expert evaluator, used a scholarly, iterative consensus-building process to develop the tool and test it using real EPs from educational scholars who followed an EP template. They revised the template in parallel with the analysis tool to ensure that EP data enabled valid and reliable evaluation. The authors created the EP template and analysis tool for scholar and program evaluation in the Educational Scholars Program, a three-year national certification program of the Academic Pediatric Association.

RESULTS

The analysis tool combines 18 quantitative and 25 qualitative items, with specifications, for objective evaluation of educational activities and scholarship.

CONCLUSIONS

The authors offer this comprehensive, yet practical tool as a method to enhance opportunities for faculty promotions and advancement, based on well-defined and documented educational outcome measures. It is relevant for clinical educators across disciplines and across institutions. Future studies will test the interrater reliability of the tool, using data from EPs written using the revised template.

Inpatient brain MRI for new-onset seizures: utility and cost effectiveness

Inpatient magnetic resonance imaging for evaluation of new-onset afebrile seizures can extend hospital stay, can add cost, and may not affect acute management. The study was to assess cost and impact on acute management of inpatient brain magnetic resonance imagings performed as part of new-onset seizure evaluation. Retrospective chart review of brain magnetic resonance imagings on pediatric inpatients admitted for new-onset afebrile seizure has been carried out. Seventy-five patients were identified. Seventy-one of the patients (95%) stayed an additional day for the magnetic resonance imaging. Thirteen had abnormal results. No patient had treatment changes based upon the magnetic resonance imaging results. If these magnetic resonance imagings had been done as an outpatient, the savings to the hospital could have been $215,575. Thus, obtaining an inpatient brain magnetic resonance imaging for evaluation of new-onset seizures did not lead to acute changes in management and added to facility costs and length of stay. Scheduling a magnetic resonance imaging as an outpatient could achieve cost savings without compromising care.

Pediatric hospitalists: report of a leadership conference

OBJECTIVES

To summarize a meeting of academic pediatric hospitalists and to describe the current state of the field.

METHODS

The Ambulatory Pediatric Association sponsored a meeting for academic pediatric hospitalists in November 2003. The purpose of the meeting was to discuss and to define roles of academic pediatric hospitalists, including their roles as clinicians, educators, and researchers, and to discuss organizational issues and unique hospitalist issues within general academic pediatrics. Workshops were held in the areas of organization and administration, academic life, research, and education. A literature review was also conducted in the areas discussed.

RESULTS

More than 130 physicians attended. Thirteen workshops were held, and all information was summarized in large-group sessions for all attendees.

CONCLUSIONS

Pediatric hospital medicine is a rapidly growing field, with an estimated 800 to 1000 pediatric hospitalists currently practicing. Initial work has defined the clinical environment and has begun to stake out a unique knowledge and skill set. The Pediatric Hospitalists in Academic Settings conference demonstrated the audience for additional development and the resources to move forward.

Introduction to pediatric hospital medicine

This article provides a brief summary of the past, present, and future of pediatric hospital medicine. In its short history, it already has made an impact on the way pediatrics is practiced and taught. There is no denying Dr. Menna's prescience when he wrote his opinion in 1990. As the field continues to emerge and mature, the current leadership is cognizant of the obstacles ahead and the need to maintain the goal of the well-being of all children. Maintaining that goal means redoubling efforts to maintain contact with primary care providers for continuity of care in and out of the hospital. Only by promoting patient- and family-centered care, inclusive of all providers, can children's health best be served.

Lessons from pediatrics residency program directors' experiences with work hour limitations in New York State

PURPOSE

To evaluate the impact of residency work hour limitations on pediatrics residency programs in New York State, and to learn lessons that can be used nationally with the implementation of the Accreditation Council of Graduate Medical Education's similar rules.

METHOD

A three-page questionnaire was mailed to all pediatrics residency program directors in New York. The questionnaire assessed methods used to accommodate the work hour limitations and perceptions of the limitations' effects.

RESULTS

Twenty-one program directors responded (68%). Only large programs used night floats and night teams to meet work hour requirements. Programs of all sizes and in all settings used cross coverage and sent residents home immediately post call. About half of the programs hired additional nonresident staff, usually nurse practitioners, physician assistants, and/or attendings. The most frequently reported effects were decreases in the amount of time residents spent in inpatient settings, patient continuity in inpatient settings, flexibility of residents' scheduling, and increased logistical work needed to maintain continuity clinic. A summary of advice to other program directors was "be creative" and "be flexible."

CONCLUSIONS

New York's pediatrics residency programs used a variety of mechanisms to meet work hour restrictions. Smaller programs had fewer methods available to them to meet such restrictions. Although the logistical work needed to maintain continuity clinic increased greatly, continuity and outpatient settings themselves were not greatly affected by work hour limitations. Inpatient settings were more affected and experienced much more in the way of change.

Cholesterol dependence of HTLV-I infection

Cholesterol-rich plasma membrane microdomains are important for entry of many viruses, including retroviruses. Depletion of cholesterol with 2-hydroxypropyl-beta-cyclodextrin inhibits entry of human T cell leukemia virus type I (HTLV-1) and HTLV-I envelope pseudotyped lentivirus particles. Using a soluble fusion protein of the HTLV-I surface envelope protein with the immunoglobulin Fc domain, the HTLV-I receptor was found to colocalize with a raft-associated marker and to cluster in specific plasma membrane microdomains. Depletion of cholesterol did not alter receptor binding activity, suggesting a requirement for cholesterol in a postbinding virus entry step.

Herpes simplex virus with highly reduced gD levels can efficiently enter and spread between human keratinocytes

The rapid spread of herpes simplex virus type 1 (HSV-1) in mucosal epithelia and neuronal tissue depends primarily on the ability of the virus to navigate within polarized cells and the tissues they constitute. To understand HSV entry and the spread of virus across cell junctions, we have previously characterized a human keratinocyte cell line, HaCaT. These cells appear to reflect cells infected in vivo more accurately than many of the cultured cells used to propagate HSV. HSV mutants lacking gE/gI are highly compromised in spread within epithelial and neuronal tissues and also show defects in cell-to-cell spread in HaCaT cells, but not in other, nonpolarized cells. HSV gD is normally considered absolutely essential for entry and cell-to-cell spread, both in cultured cells and in vivo. Here, an HSV-1 gD mutant virus, F-US6kan, was found to efficiently enter HaCaT cells and normal human keratinocytes and could spread from cell to cell without gD provided by complementing cells. By contrast, entry and spread into other cells, especially highly transformed cells commonly used to propagate HSV, were extremely inefficient. Further analyses of F-US6kan indicated that this mutant expressed extraordinarily low (1/500 wild-type) levels of gD. Neutralizing anti-gD monoclonal antibodies inhibited entry of F-US6kan, suggesting F-US6kan utilized this small amount of gD to enter cells. HaCaT cells expressed high levels of an HSV gD receptor, HveC, and entry of F-US6kan into HaCaT cells could also be inhibited with antibodies specific for HveC. Interestingly, anti-HveC antibodies were not fully able to inhibit entry of wild-type HSV-1 into HaCaT cells. These results help to uncover important properties of HSV and human keratinocytes. HSV, with exceedingly low levels of a crucial receptor-binding glycoprotein, can enter cells expressing high levels of receptor. In this case, surplus gD may be useful to avoid neutralization by anti-gD antibodies.

Mutations in herpes simplex virus glycoprotein D distinguish entry of free virus from cell-cell spread

Herpes simplex virus type 1 (HSV-1) glycoprotein D (gD) is an essential component of the entry apparatus that is responsible for viral penetration and subsequent cell-cell spread. To test the hypothesis that gD may serve distinguishable functions in entry of free virus and cell-cell spread, mutants were selected for growth on U(S)11cl19.3 cells, which are resistant to both processes due to the lack of a functional gD receptor, and then tested for their ability to enter as free virus and to spread from cell to cell. Unlike their wild-type parent, HSV-1(F), the variants that emerged from this selection, which were named SP mutants, are all capable of forming macroscopic plaques on the resistant cells. This ability is caused by a marked increase in cell-cell spread without a concomitant increase in efficiency of entry of free virus. gD substitutions that arose within these mutants are sufficient to mediate cell-cell spread in U(S)11cl19.3 cells but are insufficient to overcome the restriction to entry of free virions. These results suggest that mutations in gD (i) are sufficient but not necessary to overcome the block to cell-cell spread exhibited by U(S)11cl19.3 cells and (ii) are insufficient to mediate entry of free virus in the same cells.

Exploring intermittent transcutaneous CO2 monitoring

OBJECTIVE

To explore the accuracy of a continuous transcutaneous CO2 (T(CCO2)) monitor, used in an intermittent rather than a continuous fashion, to obtain quick (<5 mins) CO2 readings.

DESIGN

Prospective study.

SETTING

An urban pediatric intensive care unit in a university teaching hospital.

PATIENTS

A convenience sample of pediatric patients with indwelling arterial catheters.

INTERVENTION

Transcutaneous monitoring was done simultaneous with arterial blood gas monitoring.

MEASUREMENTS AND MAIN RESULTS

There were 49 simultaneous-readings on 19 patients, age 5 days to 16 years, with 13 different diagnoses. The T(CCO2) was related to the PCO2 by a Pearson product coefficient of 0.79 (p<.0005), with a mean difference of 1.94 (T(CCO2)>P(CO2) and 95% confidence interval of -0.12 to 4.07. The scatterplot produces a regression line characterized by the following equation: PCO2 = (T(CCO2)x1.05)-4.08.

CONCLUSIONS

Further study to evaluate intermittent TCCO2 as a practical clinical variable is warranted. This study should encourage refinement of the technology to be more accurate for this use.