18F-FDGPET/CT improves diagnostic certainty over the modified Duke Criteria in blood culture negative infective endocarditis

Funding Acknowledgements

Type of funding sources: None.

Introduction

Diagnosis of blood culture negative infective endocarditis (BCNIE) is challenging, with positive microbiology key in the modified Duke Criteria (mDC). ESC IE Guidelines (2015) recommend the use of 18F-FDG PET/CT (PET) in cases where transoesophageal echocardiography (TOE) is equivocal and where cardiac implantable device-related IE (CIDRE) is suspected. We explored the role of PET to improve diagnostic certainty in the challenging cohort of BCNIE.

Methods

Retrospective review of all suspected BCNIE patients undergoing PET (10/2015 to 01/2021). Myocardial suppression technique was used in all cases, and studies were assessed for valve/device avidity. Patients were classified as definite/possible/rejected IE by mDC pre- and post-PET, with incremental benefit assessed by net reclassification index (NRI) versus actual diagnosis. Actual diagnosis was defined by Endocarditis Team consensus or surgical specimen (where available) at a minimum of 2-months following index admission.

Results

PET was performed in 110/807 (13.6%) cases overall. BCNIE prevalence was 18% across the total cohort, with 25/110 (22.7%) PET studies in BCNIE patients (male = 17, mean age 65). (p = 0.16 for PET in BCNIE compared to overall). PET was undertaken in 8 CIDRE, 9 native IE (NVE) and 10 prosthetic IE (PVE); 2-patients had suspected CIDRE + PVE. TOE was performed in all cases, and surgery was required in 8/25 patients. IE was confirmed in 44% of cases.

PET sensitivity, specificity, positive and negative predictive values were 73%, 93%, 89% and 81%, respectively. Addition of PET to the mDC improved re-classification to definite or rejected IE, with NRI 0.633 (positive NRI 0.3; negative 0.333), and added weight to the original mDC classification in 14/25 (56%) of cases.

Conclusion

PET improves diagnostic certainty when combined with mDC in the evaluation of patients with BCNIE across NVE, PVE and CIDRE.

Phase I clinical results of an APC-targeted hCGβ vaccine (CDX-1307) with TLR agonists

3006

Background: Effective immunization requires efficient antigen delivery to antigen presenting cells (APCs). Antigens attached to the human antibody B11, targeting mannose receptors on APCs, have been shown to be processed and presented efficiently, and generate robust immune responses when combined with toll-like receptor (TLR) agonists. The CDX-1307 vaccine is composed of B11 fused with hCGβ, a tumor antigen correlated with advanced stage of disease and poor prognosis in a number of common epithelial cancers, but reported at variable rates of expression. Methods: Two phase I studies investigate intradermal (id) vs. systemic (iv) administration of CDX-1307. Patients with advanced epithelial cancers known to frequently express hCGβ receive 4 biweekly vaccinations of CDX-1307, alone or in combination with immunostimulants including GM-CSF (GM), the TLR3 agonist Poly-ICLC, and the TLR7/8 agonist resiquimod. Results: Dose-escalation is complete. In the id study, 37 patients received CDX-1307 at doses of 0.3, 1.0, and 2.5 mg, then 2.5 mg + GM, 2.5 mg + GM + Poly-ICLC, and 2.5 mg + GM + resiquimod. 2.5 mg + GM + Poly-ICLC + resiquimod is planned. In the iv study, 24 patients were treated at 1, 3, 10, and 30 mg, as well as 10 mg + GM and 30 mg + GM. 30 mg + GM + Poly-ICLC is enrolling. Treatment-related toxicities were generally mild to moderate with no dose-limiting toxicities, most frequently injection site reactions and fatigue in the id study, and fatigue, myalgia, and flu-like illness in the iv study. Humoral responses to hCGβ were increased in 56% of the analyzed patients receiving adjuvants. Serum hCGβ was frequently elevated at study entry or during treatment (males = 88%, females = 53%, pancreatic = 89%, colorectal = 78%, breast = 47%). hCGβ decreases were seen in some patients with immune responses. To date, a significant mixed response was seen in one patient with pancreatic cancer (id), while stable disease has been seen in 4 patients (2 with breast cancer = 25, 27 weeks and 2 with colorectal cancer = 9+ weeks). Conclusions: CDX-1307 is well tolerated and results in immune responses that are enhanced by immunostimulants. Elevated hCGβ was detected at a higher than expected frequency in these tumors.

[Table: see text]

Antigen presenting cell (APC)-targeted hCGβ vaccine for cancer therapy

3013

Background: CDX-1307 is a novel vaccine approach designed to target antigens directly into the endocytic compartments of dendritic cells (DCs) and other professional APCs. The β subunit of human chorionic gonadotropin (hCGβ) is selectively over-expressed by a number of epithelial tumors and has been reported to correlate with stage of disease and prognosis. We have coupled this tumor-associated antigen to a human monoclonal antibody (B11) that targets mannose receptors on human dendritic cells and macrophages, and have demonstrated the efficacy of this approach in preclinical models using hCGβ-expressing tumors and cell lines. Methods: In this phase I, dose-escalating study, sequential cohorts of 6 patients with relapsed epithelial tumors receive 4 biweekly intradermal injections of CDX-1307 at either 0.3, 1.0 or 2.5 mg, or 2.5 mg concurrent with GM-CSF. Objectives: safety and tolerability; DLT, humoral and cellular immune response, and clinical activity. Results: Enrollment in the first three cohorts (n=18) is complete with no DLTs. Common potential treatment-related toxicities were injection site reaction (n=5) and fatigue/malaise (n=4), and were generally mild to moderate in severity. One transient Grade 3 generalized allergic reaction in the 1.0 mg cohort was suspected possibly related to either a nut allergy or CDX-1307. One mixed response was seen, with variable effects on circulating hCGβ. CDX-1307 localized to dermal macrophages and DCs in post-treatment biopsies. Conclusions: Administration of CDX-1307 is well tolerated and results in antigen localization in APCs of the skin. Immune Response and tumor impact are under evaluation. Further development includes systemic delivery that may provide antigen targeting to a broad APC population, and combination with immunostimulants to generate optimal immune responses.

No significant financial relationships to disclose.

Protecting the public interest: issues in contracting managed behavioral health care

In recent years, state governments have begun contracting out behavioral health care to large managed for-profit organizations. This approach to mental health service delivery has resulted in realignment in roles for both state agencies and the managed care organizations. Overnight, state agencies have been transformed into contract managers of multi-million dollar capitated health plans. Managed care companies, in turn, moving into the public-sector market must adjust their service delivery to include key concepts of public interest involvement such as consumer input, public comment, and outreach. This article analyzes three public-sector transitions. Common issues in these transformations are used as a springboard for identifying key concerns which states need to monitor when developing managed care contracts.

Genetic, physical, and phenotypic characterization of the Del(13)Svea36H mouse

The Del(13)Svea36H deletion was recovered from a radiation mutagenesis experiment and represents a valuable resource for investigating gene content and function at this region of mouse Chromosome (Chr) 13 and human Chr 6p21.3-23 and 6p25. In this paper we examine the physical extent of chromosome loss and construct an integrated genetic and radiation hybrid map of the deleted segment. We show that embryos which are homozygous for the deletion die at or before implantation and that heterozygotes are subviable, with a substantial proportion of carriers dying after mid-gestation but before weaning. The majority of viable carriers exhibit a variety of phenotypes including decreased size, eyes open at birth, corneal opacity, tail kinks, and craniofacial abnormalities. Both the heterozygous viability and the penetrance of the visible phenotypes vary with genetic background.

Preoperative mobilization of circulating dendritic cells by Flt3 ligand administration to patients with metastatic colon cancer

PURPOSE

To evaluate preoperative dendritic cell (DC) mobilization and tumor infiltration after administration of Flt3 ligand (Flt3L) to patients with metastatic colon cancer.

PATIENTS AND METHODS

Twelve patients with colon cancer metastatic to the liver or lung received Flt3L (20 microg/kg/d subcutaneously for 14 days for one to three cycles at monthly intervals) before attempted metastasectomy. The number and phenotype of DCs mobilized into peripheral-blood mononuclear cells (PBMCs) were evaluated by flow cytometry. After surgical resection, metastatic tumor tissue was evaluated for DC infiltration. In vivo immune responses to recall antigens were measured.

RESULTS

After Flt3L administration, on average, the total number of leukocytes in the peripheral blood increased from 5.9 +/- 1.0 x 10(3)/mm(3) to 11.2 +/- 3.8 x 10(3)/mm(3) (mean +/- SD, P: =. 0001). The percentage of CD11c(+)CD14(-) DCs in PBMCs increased from 2.4% +/- 1.8% to 8.8% +/- 4.7% (P: =.004). Delayed-type hypersensitivity (DTH) responses to recall antigens (CANDIDA:, mumps, and tetanus) showed marginally significant increases in reactivity after Flt3L administration (P: =.06, P: =.03, and P: =.08, respectively). An increase in the number of DCs was observed at the periphery of the tumors of patients who received Flt3L compared with those of patients who had not.

CONCLUSION

Flt3L is capable of mobilizing DCs into the peripheral blood of patients with metastatic colon cancer and may be associated with increases in DC infiltration in the peritumoral regions. Flt3L mobilization is associated with a trend toward increased DTH responses to recall antigens in vivo. The use of Flt3L to increase circulating DCs for cancer immunotherapy should be considered.

Misclassification and selection bias when identifying Alzheimer's disease solely from Medicare claims records

BACKGROUND

Medicare claims as the basis for health condition adjustments is becoming a method of choice in capitation reimbursement. A recent study has found that claims-based beneficiary classification for Alzheimer's disease produces lower prevalence estimates and higher average costs than previous healthcare cost studies in this population. These sets of studies differ in data sources, period length, and in their specification of dementia.

OBJECTIVES

Participants in the Medicare Alzheimer's Disease Demonstration (MADDE) provide a sample of persons known to have some form of dementia. This group is used to test the adequacy of claims data for identifying eligible cases and any bias in expenditure differences between those flagged or not flagged by a claim in a given period.

DESIGN

A prospective cohort design using up to 36 months of claims data.

SETTING

The demonstration enrolled 4166 participants in treatment, and 3942 in a control group in eight communities across the US. Cases were combined in this analysis.

PARTICIPANTS

Persons with available Medicare Part A & B claims data: those receiving care under fee for service reimbursement were used in the analysis. A total of 5379 MADDE cases received fee for service care during 1991 and 1992, the period of primary interest in the analysis.

MEASUREMENT

Client health and functional status interviews and Medicare Part A & B claims.

RESULTS

Less than 20% of MADDE participants were classified with Dementia of the Alzheimer type (DAT) from a single year of claims although 68% had a DAT diagnosis from a referring physician. Annualized expenditures were 1.7 times higher among those with DAT from claims compared with those known otherwise to have dementia but who had not been identified with this condition from Medicare claims.

CONCLUSION

Underclassification of dementia from claims records can be partially remedied by increasing the period during which claims are compiled, but additional diagnostic sources will likely be needed to increase prevalence counts closer to 100% of true cases. Risk adjustment based on a single year of reported claims expenditures may overpay providers, at least in the short term, because payment incentives will likely increase prevalence reporting.

Effects of the Medicare Alzheimer's disease demonstration on Medicare expenditures

Applicants were randomized either into a group with a limited Medicare community care service benefit and case management or into a control group receiving their regular medical care. Analyses assess whether or not community care management affected health care use. A tendency toward reduced expenditures was observed for the treatment group, combining all demonstration sites, and when observing each separately. These differences were or approached statistical significance in two sites for Medicare Part A and Parts A and B expenditures averaged over 3 years. Expenditure reductions approached budget neutrality with program costs in two sites.

Nucleotide sequencing of HLA-DQ gene second exons in Chinese homozygous cells

Six HLA class I and class II-homozygous Chinese cell lines with unique HLA-Dw types were studied. Since the majority of HLA class II nucleotide sequence polymorphism is localized within the second exons of the genes, we used the polymerase chain reaction (PCR) to amplify these regions in HLA-DQA and DQB genes and subsequently determined the nucleotide sequences. No unique DQA1 or DQB1 alleles were found. However, a new haplotype of DQA1*0601-DQB1*0301-DRB1*1202 was found in two cells; and DQA1*03011 was found in association with DR9 in another two cells. This indicates that new DR-DQ associations may explain the observed new HLA-Dw types. The DQB2 sequences were identical in all six cells and were identical to a sequence previously reported in a DR6 haplotype. The DQA2 sequences from two clones obtained from two cells differed from each other and from previously reported sequences. The results show that the DQA1 and DQB1 alleles in the Chinese individuals studied are as previously reported in Caucasian populations and as such may be typed by restriction fragment-length polymorphism (RFLP) or PCR-sequence-specific oligonucleotide typing (PCR-SSO) or PCR-RFLP using conventional probe or restriction enzyme sets.

Education and empowerment: securing nursing's future

If nurses are to make a difference in health care, they must break from the Nightingale tradition of a "good", unquestioning woman. They must become more flexible, more assertive and reflective through education.

Whither ICN on its 90th birthday

ICN was 90 years old this year and, from all accounts, is still viable and will continue to be meaningful for nurses and nursing well into the year 2000. As it nears its 100th birthday it is only appropriate that we look back in retrospect at accomplishments, take stock of the present situation of nursing worldwide and contemplate future goals. ICN has its longterm plan (page 168), but it is flexible so that it can adapt to changing needs. Below, present and former (one as far back as 1961) members of the ICN team evaluate ICN's worthiness and suggest how it can better serve the nursing profession.