Characteristics and Clinical Outcomes of Children and Adolescents Aged <18 Years Hospitalized with COVID-19 - Six Hospitals, United States, July-August 2021.

During June 2021, the highly transmissible† B.1.617.2 (Delta) variant of SARS-CoV-2, the virus that causes COVID-19, became the predominant circulating strain in the United States. U.S. pediatric COVID-19-related hospitalizations increased during July-August 2021 following emergence of the Delta variant and peaked in September 2021.§ As of May 12, 2021, CDC recommended COVID-19 vaccinations for persons aged ≥12 years,¶ and on November 2, 2021, COVID-19 vaccinations were recommended for persons aged 5-11 years.** To date, clinical signs and symptoms, illness course, and factors contributing to hospitalizations during the period of Delta predominance have not been well described in pediatric patients. CDC partnered with six children's hospitals to review medical record data for patients aged <18 years with COVID-19-related hospitalizations during July-August 2021.†† Among 915 patients identified, 713 (77.9%) were hospitalized for COVID-19 (acute COVID-19 as the primary or contributing reason for hospitalization), 177 (19.3%) had incidental positive SARS-CoV-2 test results (asymptomatic or mild infection unrelated to the reason for hospitalization), and 25 (2.7%) had multisystem inflammatory syndrome in children (MIS-C), a rare but serious inflammatory condition associated with COVID-19.§§ Among the 713 patients hospitalized for COVID-19, 24.7% were aged <1 year, 17.1% were aged 1-4 years, 20.1% were aged 5-11 years, and 38.1% were aged 12-17 years. Approximately two thirds of patients (67.5%) had one or more underlying medical conditions, with obesity being the most common (32.4%); among patients aged 12-17 years, 61.4% had obesity. Among patients hospitalized for COVID-19, 15.8% had a viral coinfection¶¶ (66.4% of whom had respiratory syncytial virus [RSV] infection). Approximately one third (33.9%) of patients aged <5 years hospitalized for COVID-19 had a viral coinfection. Among 272 vaccine-eligible (aged 12-17 years) patients hospitalized for COVID-19, one (0.4%) was fully vaccinated.*** Approximately one half (54.0%) of patients hospitalized for COVID-19 received oxygen support, 29.5% were admitted to the intensive care unit (ICU), and 1.5% died; of those requiring respiratory support, 14.5% required invasive mechanical ventilation (IMV). Among pediatric patients with COVID-19-related hospitalizations, many had severe illness and viral coinfections, and few vaccine-eligible patients hospitalized for COVID-19 were vaccinated, highlighting the importance of vaccination for those aged ≥5 years and other prevention strategies to protect children and adolescents from COVID-19, particularly those with underlying medical conditions.

Plasma Metagenomic Next-Generation Sequencing Assay for Identifying Pathogens: a Retrospective Review of Test Utilization in a Large Children's Hospital.

Plasma metagenomic next-generation sequencing (mNGS) is a new diagnostic method used to potentially identify multiple pathogens with a single DNA-based diagnostic test. The test is expensive, and little is understood about where it fits into the diagnostic schema. We describe our experience at Texas Children's Hospital with the mNGS assay by Karius from Redwood City, CA, to determine whether mNGS offers additional diagnostic value when performed within 1 week before or after conventional testing (CT) (i.e., concurrently). We performed a retrospective review of all patients who had mNGS testing from April to June of 2019. Results for mNGS testing, collection time, time of result entry into the electronic medical record, and turnaround time were compared to those for CT performed concurrently. Discordant results were further reviewed for changes in antimicrobials due to the additional organism(s) identified by mNGS. Sixty patients had mNGS testing; the majority were immunosuppressed (62%). There was 61% positive agreement and 58% negative agreement between mNGS and CT. The mean time of result entry into the electronic medical record for CT was 3.5 days earlier than the mean result time for mNGS. When an additional organism(s) was identified by mNGS, antimicrobials were changed 26% of the time. On average, CT provided the same result as mNGS, but sooner than mNGS. When additional organisms were identified by mNGS, there was no change in management in the majority of cases. Overall, mNGS added little diagnostic value when ordered concurrently with CT.

Inappropriate Laboratory Testing: Significant Waste Quantified by a Large-Scale Year-Long Study of Medicare and Commercial Payer Reimbursement.

CONTEXT.­: Laboratory testing, beyond what is essential for managing health, is considered low-value care, posing patient risks and wasting resources. Measuring excess testing on a national level is crucial to identify waste and optimize healthcare resource allocation for maximum impact. OBJECTIVE.­: To measure inappropriate laboratory testing and its cost across Medicare and many US commercial payers. DESIGN.­: A retrospective analysis on 2019 claims data measured the frequency of 4 commonly used laboratory tests among 64 million individuals with Medicare and 168 million with commercial insurance. Tests included 25-hydroxy vitamin D, prostate-specific antigen, lipid panel, and hemoglobin A1c. Clinical guidelines, medical literature, and payer recommendations were used to determine appropriate testing frequencies. Costs of excessive testing were calculated using the 2019 clinical lab fee schedule. A targeted analysis of 2022 data confirmed 2019 trends. RESULTS.­: Analysis of ∼84 million tests from ∼1 billion outpatient test claim records revealed that 7% to 51% of tests exceeded recommended frequencies, with some egregious overuse: for example hemoglobin-A1c or prostate-specific antigen every week. The conservative cost estimate for 4 excess tests surpassed $350 million. CONCLUSIONS.­: This extensive study, involving 232 million people, found that 14.4 million of 60.5 million individuals (23.8%) tested had undergone excessive laboratory testing, with likely little benefit and possible harm. Extrapolating findings to all laboratory testing suggests that Medicare alone may have incurred direct excess expenses from $1.95 to $3.28 billion in 2019, without factoring the hidden costs of excessive testing (eg, downstream care). Addressing unnecessary testing is crucial to lowering costs and redirecting resources for greater patient benefit.

Structure and Funding of Clinical Informatics Fellowships: A National Survey of Program Directors.

BACKGROUND: In 2011, the American Board of Medical Specialties established clinical informatics (CI) as a subspecialty in medicine, jointly administered by the American Board of Pathology and the American Board of Preventive Medicine. Subsequently, many institutions created CI fellowship training programs to meet the growing need for informaticists. Although many programs share similar features, there is considerable variation in program funding and administrative structures. OBJECTIVES: The aim of our study was to characterize CI fellowship program features, including governance structures, funding sources, and expenses. METHODS: We created a cross-sectional online REDCap survey with 44 items requesting information on program administration, fellows, administrative support, funding sources, and expenses. We surveyed program directors of programs accredited by the Accreditation Council for Graduate Medical Education between 2014 and 2021. RESULTS: We invited 54 program directors, of which 41 (76%) completed the survey. The average administrative support received was $27,732/year. Most programs (85.4%) were accredited to have two or more fellows per year. Programs were administratively housed under six departments: Internal Medicine (17; 41.5%), Pediatrics (7; 17.1%), Pathology (6; 14.6%), Family Medicine (6; 14.6%), Emergency Medicine (4; 9.8%), and Anesthesiology (1; 2.4%). Funding sources for CI fellowship program directors included: hospital or health systems (28.3%), clinical departments (28.3%), graduate medical education office (13.2%), biomedical informatics department (9.4%), hospital information technology (9.4%), research and grants (7.5%), and other sources (3.8%) that included philanthropy and external entities. CONCLUSION: CI fellowships have been established in leading academic and community health care systems across the country. Due to their unique training requirements, these programs require significant resources for education, administration, and recruitment. There continues to be considerable heterogeneity in funding models between programs. Our survey findings reinforce the need for reformed federal funding models for informatics practice and training.

Absence of XMRV retrovirus and other murine leukemia virus-related viruses in patients with chronic fatigue syndrome.

Chronic fatigue syndrome (CFS) is a multisystem disorder characterized by prolonged and severe fatigue that is not relieved by rest. Attempts to treat CFS have been largely ineffective primarily because the etiology of the disorder is unknown. Recently, CFS has been associated with xenotropic murine leukemia virus-related virus (XMRV) as well as other murine leukemia virus (MLV)-related viruses, though not all studies have found these associations. We collected blood samples from 100 CFS patients and 200 self-reported healthy volunteers from the same geographical area. We analyzed these in a blind manner using molecular, serological, and viral replication assays. We also analyzed samples from patients in the original study that reported XMRV in CFS patients. We did not find XMRV or related MLVs either as viral sequences or infectious viruses, nor did we find antibodies to these viruses in any of the patient samples, including those from the original study. We show that at least some of the discrepancy with previous studies is due to the presence of trace amounts of mouse DNA in the Taq polymerase enzymes used in these previous studies. Our findings do not support an association between CFS and MLV-related viruses, including XMRV, and the off-label use of antiretrovirals for the treatment of CFS does not seem justified at present.

XMRV is present in malignant prostatic epithelium and is associated with prostate cancer, especially high-grade tumors.

Xenotropic murine leukemia virus-related virus (XMRV) was recently discovered in human prostate cancers and is the first gammaretrovirus known to infect humans. While gammaretroviruses have well-characterized oncogenic effects in animals, they have not been shown to cause human cancers. We provide experimental evidence that XMRV is indeed a gammaretrovirus with protein composition and particle ultrastructure highly similar to Moloney murine leukemia virus (MoMLV), another gammaretrovirus. We analyzed 334 consecutive prostate resection specimens, using a quantitative PCR assay and immunohistochemistry (IHC) with an anti-XMRV specific antiserum. We found XMRV DNA in 6% and XMRV protein expression in 23% of prostate cancers. XMRV proteins were expressed primarily in malignant epithelial cells, suggesting that retroviral infection may be directly linked to tumorigenesis. XMRV infection was associated with prostate cancer, especially higher-grade cancers. We found XMRV infection to be independent of a common polymorphism in the RNASEL gene, unlike results previously reported. This finding increases the population at risk for XMRV infection from only those homozygous for the RNASEL variant to all individuals. Our observations provide evidence for an association of XMRV with malignant cells and with more aggressive tumors.

A Daily Operational Huddle and a Real-Time Communication Application Improve Efficiency of Laboratory Processes.

CONTEXT.­: Clinical laboratory processes that require cooperation among geographically distinct sections often face challenges. We describe these challenges as related to the Gram staining of cerebrospinal fluid, a key test in the management of patients with suspected central nervous system infections, and our attempts to improve quality outcomes. OBJECTIVE.­: To evaluate multiple tools and strategies for their effectiveness in optimizing the turnaround time of tests sharing a specimen or workflow. DESIGN.­: Over the course of 5 years, the turnaround time of cerebrospinal fluid Gram stain was studied at one of the largest children's health systems in the United States. Baseline data showed suboptimal compliance to targeted turnaround times. A conventional approach to process standardization and 2 innovative tools that facilitate horizontal integration were applied to the main campus laboratory as follows: a daily operational huddle and a novel electronic communication application that was interfaced with the laboratory information system. Turnaround time and its variation were assessed. Two other hospital laboratories within the health system that did not undergo these quality interventions served as controls. RESULTS.­: Standardization of processes reduced the variability of turnaround time but only minimally shortened it. In contrast, an interteam daily huddle that monitored key quality metrics together with the communication application improved turnaround time significantly and sustainably. CONCLUSIONS.­: Communication strategies involving a physical or virtual gathering of laboratory representatives encourage horizontal communication and improve turnaround times. These tools are generally applicable and could be used to improve other processes in healthcare, especially those where a workflow is shared between 2 geographically distinct areas of a health system.

Factors Associated With Severe Illness in Patients Aged <21 Years Hospitalized for COVID-19.

OBJECTIVES: To describe coronavirus disease 2019 (COVID-19)-related pediatric hospitalizations during a period of B.1.617.2 (Δ) variant predominance and to determine age-specific factors associated with severe illness. METHODS: We abstracted data from medical charts to conduct a cross-sectional study of patients aged <21 years hospitalized at 6 United States children's hospitals from July to August 2021 for COVID-19 or with an incidental positive severe acute respiratory syndrome coronavirus 2 test. Among patients with COVID-19, we assessed factors associated with severe illness by calculating age-stratified prevalence ratios (PR). We defined severe illness as receiving high-flow nasal cannula, positive airway pressure, or invasive mechanical ventilation. RESULTS: Of 947 hospitalized patients, 759 (80.1%) had COVID-19, of whom 287 (37.8%) had severe illness. Factors associated with severe illness included coinfection with respiratory syncytial virus (RSV) (PR 3.64) and bacteria (PR 1.88) in infants; RSV coinfection in patients aged 1 to 4 years (PR 1.96); and obesity in patients aged 5 to 11 (PR 2.20) and 12 to 17 years (PR 2.48). Having ≥2 underlying medical conditions was associated with severe illness in patients aged <1 (PR 1.82), 5 to 11 (PR 3.72), and 12 to 17 years (PR 3.19). CONCLUSIONS: Among patients hospitalized for COVID-19, factors associated with severe illness included RSV coinfection in those aged <5 years, obesity in those aged 5 to 17 years, and other underlying conditions for all age groups <18 years. These findings can inform pediatric practice, risk communication, and prevention strategies, including vaccination against COVID-19.

Changes in Test Volumes During Coronavirus Disease 2019 (COVID-19): A Laboratory Stewardship Opportunity.

CONTEXT.­: Coronavirus disease 2019 (COVID-19) changed the dynamics of health care delivery, shifting patient priorities and deferring care perceived as less urgent. Delayed or eliminated care may place patients at risk for adverse outcomes. OBJECTIVE.­: To identify opportunities for laboratory test stewardship to close potential gaps in care created by the COVID-19 pandemic. DESIGN.­: The study was a retrospective time series design examining laboratory services received before and during the COVID-19 pandemic at a large metropolitan health system serving women and children. RESULTS.­: Laboratory test volumes displayed 3 distinct patterns: (1) a decrease during state lockdown, followed by near-complete or complete recovery; (2) no change; and (3) a persistent decrease. Tests that diagnose or monitor chronic illness recovered only partially. For example, hemoglobin A1c initially declined 80% (from 2232 for April 2019 to 452 for April 2020), and there was a sustained 16% drop (28-day daily average 117 at August 30, 2019, to 98 at August 30, 2020) 4 months later. Blood lead dropped 39% (from 2158 for April 2019 to 1314 for April 2020) and remained 23% lower after 4 months. CONCLUSIONS.­: The pandemic has taken a toll on patients, practitioners, and health systems. Laboratory professionals have access to data that can provide insight into clinical practice and identify pandemic-related gaps in care. During the pandemic, the biggest patient threat is underuse, particularly among tests to manage chronic diseases and for traditionally underserved communities and people of color. A laboratory stewardship program, focused on peri-pandemic care, positions pathologists and other laboratory professionals as health care leaders with a commitment to appropriate, equitable, and efficient care.

Performance of six SARS-CoV-2 RNA detection systems in symptomatic and asymptomatic pediatric and maternal patients.

Aim: This study evaluated the real-world performance of six test systems for detection of SARS-CoV-2 in 138 pediatric and 110 adult maternal patients. Materials & methods: Nasopharyngeal swabs were tested directly using the Aptima™ SARS-CoV-2 (Aptima) and Simplexa™ COVID-19 Direct (Simplexa), and with Altona RealStar® RT-PCR and CDC RT-PCR with nucleic acid extracted on the Roche® MagNA Pure 96 (Altona-MP96) or bioMérieux EMAG® (Altona-EMAG). Results/Conclusion: Overall percent-positive and percent-negative agreements among the six test systems were, respectively: Aptima: 94.8 and 100%; Altona-MP96: 96.5 and 99.3%; CDC-MP96: 100 and 99.3%; Altona-EMAG: 86.1 and 100%; CDC-EMAG: 98.2 and 100%; Simplexa: 87 and 99.2%. The six test systems showed agreement ranging from 92.7 (κ = 0.85) to 98.8% (κ = 0.98).

The Importance of Genetics Experts in Optimizing Genetic Test Orders Through Prospective and Retrospective Reviews.

OBJECTIVES: To demonstrate the impact of genetics specialists on identifying test order errors and improving reimbursement for genetic testing. METHODS: Forty-four cases in which whole exome sequencing (WES) was performed but not reimbursed were reviewed by a genetic counselor through simulated prospective and retrospective reviews. RESULTS: Fifty-two percent of WES requests were ordered by nongenetics providers. Retrospective review revealed that 50% of cases were denied because of contractual constraints on billing. If review by a genetic counselor had occurred in real time, modifications or cancellations would have been recommended in 82% of the cases. CONCLUSIONS: A laboratory stewardship program involving genetics experts identified test order errors and opportunities for improved reimbursement and cost savings. Significant variables affected reimbursement, including inpatient status, payer criteria, and ordering provider specialty.

Transforming Laboratory Utilization Review into Laboratory Stewardship: Guidelines by the PLUGS National Committee for Laboratory Stewardship.

Appropriate utilization of clinical laboratory services is important for patient care and requires institutional stewardship. Clinical laboratory stewardship programs are dedicated to improving the ordering, retrieval, and interpretation of appropriate laboratory tests. In addition, these programs focus on developing, maintaining, and improving systems to provide proper financial coverage for medically necessary testing. Overall, clinical laboratory stewardship programs help clinicians improve the quality of patient care while reducing costs to patients, hospitals, and health systems. This document, which was created by a new multiinstitutional committee interested in promoting and formalizing laboratory stewardship, summarizes core elements of successful hospital-based clinical laboratory stewardship programs. The core elements will also be helpful for independent commercial clinical laboratories.

T2Candida Provides Rapid and Accurate Species Identification in Pediatric Cases of Candidemia.

OBJECTIVES: The goal of this study is to assess the ability of the T2Candida platform (T2 Biosystems, Lexington, MA) to accurately identify Candida species from pediatric blood specimens with low volumes. METHODS: Whole blood from 15 children with candidemia was collected immediately following blood culture draw. The amount of blood required by the system was reduced by pipetting whole blood directly onto the T2Candida cartridge. Specimens were subsequently run on the T2Dx Instrument (T2 Biosystems). RESULTS: The T2Candida panel provided the appropriate result for each specimen compared with blood culture-based species identification and correctly identified 15 positive and nine negative results in 3 to 5 hours. While the time to species identification for blood culture was not reported, the T2Candida results include species data. CONCLUSIONS: T2Candida can be used to efficiently diagnose or rule out candidemia using low-volume blood specimens from pediatric patients. This could result in improved time to appropriate antifungal therapy or reduction in unnecessary empirical antifungal therapy.

Detecting retroviral sequences in chronic fatigue syndrome.

XMRV or xenotropic murine leukemia virus-related retrovirus, a recently discovered retrovirus, has been linked to both prostate cancer and chronic fatigue syndrome (CFS). Recently, the teams of Drs. Shyh-Ching Lo and Harvey Alter discovered the presence of sequences closely related to XMRV in the blood of 86.5% of patients with CFS [1]. These findings are important because since the initial discovery of XMRV in CFS, several studies have failed to find XMRV in specimens collected from CFS patients. While the current study also did not find XMRV in CFS, Lo et al. did detect sequences that belong to polytropic mouse endogenous retroviruses (PMV), which share considerable similarity with XMRV. Criteria for future studies that will help bring greater clarity to the issue of retroviral sequences in CFS are proposed below.

Raltegravir is a potent inhibitor of XMRV, a virus implicated in prostate cancer and chronic fatigue syndrome.

BACKGROUND: Xenotropic murine leukemia-related retrovirus (XMRV) is a recently discovered retrovirus that has been linked to human prostate cancer and chronic fatigue syndrome (CFS). Both diseases affect a large fraction of the world population, with prostate cancer affecting one in six men, and CFS affecting an estimated 0.4 to 1% of the population. PRINCIPAL FINDINGS: Forty-five compounds, including twenty-eight drugs approved for use in humans, were evaluated against XMRV replication in vitro. We found that the retroviral integrase inhibitor, raltegravir, was potent and selective against XMRV at submicromolar concentrations, in MCF-7 and LNCaP cells, a breast cancer and prostate cancer cell line, respectively. Another integrase inhibitor, L-000870812, and two nucleoside reverse transcriptase inhibitors, zidovudine (ZDV), and tenofovir disoproxil fumarate (TDF) also inhibited XMRV replication. When combined, these drugs displayed mostly synergistic effects against this virus, suggesting that combination therapy may delay or prevent the selection of resistant viruses. CONCLUSIONS: If XMRV proves to be a causal factor in prostate cancer or CFS, these discoveries may allow for rational design of clinical trials.

Mutational analysis of the N-terminal domain of Moloney murine leukemia virus capsid protein.

Retroviral capsid (CA) proteins contain a structurally conserved N-terminal domain (NTD) consisting of a beta-hairpin and six to seven alpha-helices. To examine the role of this domain in Moloney murine leukemia virus (MoMLV) replication, we analyzed 18 insertional mutations in this region. All mutants were noninfectious. Based on the results of this analysis and our previous studies on additional mutations in this domain, we were able to divide the NTD of MoMLV CA into three functional regions. The first functional region included the region near the N terminus that forms the beta-hairpin and was shown to control normal maturation of virions. The second region included the helix 4/5 loop and was essential for the formation of spherical cores. The third region encompassed most of the NTD except for the above loop. Mutants of this region assembled imperfect cores, as seen by detailed electron microscopy analyses, yet the resulting particles were efficiently released from cells. The mutants were defective at a stage immediately following entry of the core into cells. Despite possessing functional reverse transcriptase machinery, these mutant virions did not initiate reverse transcription in cells. This block could be due to structural defects in the assembling core or failure of an essential host protein to interact with the mutant CA protein, both of which may prevent correct disassembly upon entry of the virus into cells. Future studies are needed to understand the mechanism of these blocks and to target these regions pharmacologically to inhibit retroviral infection at additional stages.

Functional analysis of hepatitis C virus envelope proteins, using a cell-cell fusion assay.

Hepatitis C virus (HCV) envelope proteins mediate the entry of virus into cells by binding to cellular receptors, resulting in fusion of the viral membrane with the host cell membrane and permitting the viral genome to enter the cytoplasm. We report the development of a robust and reproducible cell-cell fusion assay using envelope proteins from commonly occurring genotypes of HCV. The assay scored HCV envelope protein-mediated fusion by the production of fluorescent green syncytia and allowed us to elucidate many aspects of HCV fusion, including the pH of fusion, cell types that permit viral entry, and the conformation of envelope proteins essential for fusion. We found that fusion could be specifically inhibited by anti-HCV antibodies and by at least one peptide. We also generated a number of insertional mutations in the envelope proteins and tested nine of these using the fusion assay. We demonstrate that this fusion assay is a powerful tool for understanding the mechanism of HCV-mediated fusion, elucidating mutant function, and testing antiviral agents.

A small loop in the capsid protein of Moloney murine leukemia virus controls assembly of spherical cores.

We report the identification of a novel domain in the Gag protein of Moloney murine leukemia virus (MoLV) that is important for the formation of spherical cores. Analysis of 18 insertional mutations in the N-terminal domain of the capsid protein (CA) identified 3 that were severely defective for viral assembly and release. Transmission electron microscopy of cells producing these mutants showed assembly of Gag proteins in large, flat or dome-shaped patches at the plasma membrane. Spherical cores were not formed, and viral particles were not released. This late assembly/release block was partially rescued by wild-type virus. All three mutations localized to the small loop between alpha-helices 4 and 5 of CA, analogous to the cyclophilin A-binding loop of human immunodeficiency virus type 1 CA. In the X-ray structure of the hexameric form of MLV CA, this loop is located at the periphery of the hexamer. The phenotypes of mutations in this loop suggest that formation of a planar lattice of Gag is unhindered by mutations in the loop. However, the lack of progression of these planar structures to spherical ones suggests that mutations in this loop may prevent formation of pentamers or of stable pentamer-hexamer interactions, which are essential for the formation of a closed, spherical core. This region in CA, focused to a few residues of a small loop, may offer a novel therapeutic target for retroviral diseases.

T-Cell lymphoblastic lymphoma presenting as bilateral multinodular breast masses: a case report and review of the literature.

Non-Hodgkin lymphoma of T-cell lineage involving the breast is rare. We report on a 41-year-old woman with T-cell lymphoblastic lymphoma who presented with multiple bilateral breast masses. The patient was treated with intensive chemotherapy and mediastinal and whole-brain irradiation. She remains in complete remission 24 months after diagnosis. The clinical, histologic, phenotypic, and cytogenetic features are described, with a review of the literature.