Lymphatic coagulation and neutrophil extracellular traps in lung-draining lymph nodes of COVID-19 decedents

Clinical manifestations of severe COVID-19 include coagulopathies that are exacerbated by the formation of neutrophil extracellular traps (NETs). Here, we report that pulmonary lymphatic vessels, which traffic neutrophils and other immune cells to the lung-draining lymph node (LDLN), can also be blocked by fibrin clots in severe COVID-19. Immunostained tissue sections from COVID-19 decedents revealed widespread lymphatic clotting not only in the lung but also in the LDLN, where the extent of clotting correlated with the presence of abnormal, regressed, or missing germinal centers (GCs). It strongly correlated with the presence of intralymphatic NETs. In mice, tumor necrosis factor α induced intralymphatic fibrin clots; this could be inhibited by DNase I, which degrades NETs. In vitro, TNF-α induced lymphatic endothelial cell upregulation of ICAM-1 and CXCL8, among other neutrophil-recruiting factors, as well as thrombomodulin downregulation; in decedents, lymphatic clotting in LDLNs. In a separate cohort of hospitalized patients, serum levels of Myeloperoxidase-DNA (MPO-DNA, a NET marker) inversely correlated with antiviral antibody titers, but D-dimer levels, indicative of blood thrombosis, did not correlate with either. Patients with high MPO-DNA but low D-dimer levels generated poor antiviral antibody titers. This study introduces lymphatic coagulation in lungs and LDLNs as a clinical manifestation of severe COVID-19 and suggests the involvement of NETosis of lymphatic-trafficking neutrophils. It further suggests that lymphatic clotting may correlate with impaired formation or maintenance of GCs necessary for robust antiviral antibody responses, although further studies are needed to determine whether and how lymphatic coagulation affects adaptive immune responses.

Pulmonary Parenchymal Changes in COVID-19 Survivors

BACKGROUND

As the COVID-19 pandemic moves into the survivorship phase, questions regarding long-term lung damage remain unanswered. Previous histopathologic studies are limited to autopsy reports. We studied lung specimens from COVID-19 survivors who underwent elective lung resections to determine whether postacute histopathologic changes are present.

METHODS

This multicenter observational study included 11 adult COVID-19 survivors who had recovered but subsequently underwent unrelated elective lung resection for indeterminate lung nodules or lung cancer. We compared these against an age- and procedure-matched control group who never contracted COVID-19 (n = 5) and an end-stage COVID-19 group (n = 3). A blinded pulmonary pathologist examined the lung parenchyma focusing on 4 compartments: airways, alveoli, interstitium, and vasculature.

RESULTS

Elective lung resection was performed in 11 COVID-19 survivors with asymptomatic (n = 4), moderate (n = 4), and severe (n = 3) COVID-19 infections at a median 68.5 days (range 24-142 days) after the COVID-19 diagnosis. The most common operation was lobectomy (75%). Histopathologic examination identified no differences between the lung parenchyma of COVID-19 survivors and controls across all compartments examined. Conversely, patients in the end-stage COVID-19 group showed fibrotic diffuse alveolar damage with intra-alveolar macrophages, organizing pneumonia, and focal interstitial emphysema.

CONCLUSIONS

In this study to examine the lung parenchyma of COVID-19 survivors, we did not find distinct postacute histopathologic changes to suggest permanent pulmonary damage. These results are reassuring for COVID-19 survivors who recover and become asymptomatic.

Donor leukocyte trafficking during human ex vivo lung perfusion

Background

Ex vivo lung perfusion (EVLP) is used to assess and preserve lungs prior to transplantation. However, its inherent immunomodulatory effects are not completely understood. We examine perfusate and tissue compartments to determine the change in immune cell composition in human lungs maintained on EVLP.

Methods

Six human lungs unsuitable for transplantation underwent EVLP. Tissue and perfusate samples were obtained during cold storage and at 1‐, 3‐ and 6‐h during perfusion. Flow cytometry, immunohistochemistry, and bead‐based immunoassays were used to measure leukocyte composition and cytokines. Mean values between baseline and time points were compared by Student's t test.

Results

During the 1st hour of perfusion, perfusate neutrophils increased (+22.2 ± 13.5%, p < 0.05), monocytes decreased (−77.5 ± 8.6%, p < 0.01) and NK cells decreased (−61.5 ± 22.6%, p < 0.01) compared to cold storage. In contrast, tissue neutrophils decreased (−22.1 ± 12.2%, p < 0.05) with no change in monocytes and NK cells. By 6 h, perfusate neutrophils, NK cells, and tissue neutrophils were similar to baseline. Perfusate monocytes remained decreased, while tissue monocytes remained unchanged. There was no significant change in B cells or T cell subsets. Pro‐inflammatory cytokines (IL‐1b, G‐CSF, IFN‐gamma, CXCL2, CXCL1 granzyme A, and granzyme B) and lymphocyte activating cytokines (IL‐2, IL‐4, IL‐6, IL‐8) increased during perfusion.

Conclusions

Early mobilization of innate immune cells occurs in both perfusate and tissue compartments during EVLP, with neutrophils and NK cells returning to baseline and monocytes remaining depleted after 6 h. The immunomodulatory effect of EVLP may provide a therapeutic window to decrease the immunogenicity of lungs prior to transplantation.

A series of COVID-19 autopsies with clinical and pathologic comparisons to both seasonal and pandemic influenza

Autopsies of patients who have died from COVID‐19 have been crucial in delineating patterns of injury associated with SARS‐CoV‐2 infection. Despite their utility, comprehensive autopsy studies are somewhat lacking relative to the global burden of disease, and very few comprehensive studies contextualize the findings to other fatal viral infections. We developed a novel autopsy protocol in order to perform postmortem examinations on victims of COVID‐19 and herein describe detailed clinical information, gross findings, and histologic features observed in the first 16 complete COVID‐19 autopsies. We also critically evaluated the role of ancillary studies used to establish a diagnosis of COVID‐19 at autopsy, including immunohistochemistry (IHC), in situ hybridization (ISH), and electron microscopy (EM). IHC and ISH targeting SARS‐CoV‐2 were comparable in terms of the location and number of infected cells in lung tissue; however, nonspecific staining of bacteria was seen occasionally with IHC. EM was unrevealing in blindly sampled tissues. We then compared the clinical and histologic features present in this series to six archival cases of fatal seasonal influenza and six archival cases of pandemic influenza from the fourth wave of the ‘Spanish Flu’ in the winter of 1920. In addition to routine histology, the inflammatory infiltrates in the lungs of COVID‐19 and seasonal influenza victims were compared using quantitative IHC. Our results demonstrate that the clinical and histologic features of COVID‐19 are similar to those seen in fatal cases of influenza, and the two diseases tend to overlap histologically. There was no significant difference in the composition of the inflammatory infiltrate in COVID‐19 and influenza at sites of acute lung injury at the time of autopsy. Our study underscores the relatively nonspecific clinical features and pathologic changes shared between severe cases of COVID‐19 and influenza, while also providing important caveats to ancillary methods of viral detection.

Abstract OT2-04-01: An open label, phase II trial of continuous low-irradiance photodynamic therapy (CLIPT) using verteporfin for the treatment of cutaneous breast cancer metastases

Background

Cutaneous metastases occur in approximately 20% of patients (pts) with metastatic breast cancer (mBC) and can be highly symptomatic and distressing. Radiation therapy is frequently used, but progression often occurs quickly. Systemic therapies are also typically used, but also often result in limited benefit. Photodynamic therapy is a promising approach with encouraging results in small studies. Here we will evaluate a novel Continuous Low-Irradiance Photodynamic Therapy (CLIPT) system that emits 690nm LED via a handheld Power Pack attached to a single-use sterile Light Patch to deliver a total energy level of 20J/cm2. Verteporfin (Visudyne®) is a photosensitizer approved for ophthalmological use that, when combined with CLIPT, generates activated oxygen species which can destroy tumor cells with limited normal tissue reaction.

Methods

This open label, Phase 2 study will evaluate the efficacy and safety of CLIPT with verteporfin in 15 patients with cutaneous lesions from mBC. Patients will receive a single IV injection of Verteporfin on day 1. The 9x9cm Light Patch with an adhesive border is placed over the treatment site and attached to the CLIPT portable Power Pack. The patient turns the device on at home 6 hours after the Verteprofin injection and it automatically turns off after 24 hours. The patient then removes the Light Patch and returns to clinic on day 3. The primary endpoint is objective response rate (RR) at 3 weeks following CLIPT using a modified RECIST which accounts for nodular or diffuse plaque-like lesions. Response will be confirmed by independent dermatologist review. Secondary endpoints include RR at 2, 8 and 12 weeks, toxicity, and quality of life (using FACT-B and Brief Pain Inventory). A novel Participant Symptom Scale (PSS) will also be used in which the first 8 patients will list their most distressing symptoms from cutaneous metastases and score the severity of the symptoms from 1 to 10. The six most common symptoms among the first 8 patients will then be used in the PSS for the remaining 7 patients. The PSS will be assessed at baseline and at subsequent visits to explore any improvement in severity of symptoms after treatment with CLIPT. Patients who derive clinical benefit may be retreated up to 3 times to the same or different region. Eligible patients will have: cutaneous metastases from mBC with measurable disease by protocol defined modified RECIST 1.1, ≥ 1 line of prior systemic or local therapy for mBC, ≥ 14 days from prior systemic therapy or 60 days from radiation to target lesion, and no expectation for systemic therapy for ≥ 14 days after CLIPT. RR will be reported with 95% CI. With 15 patients, if ≥ 3 responses (RR ≥ 20%) are observed, the null hypothesis of RR ≤ 5% will be rejected. At the time of abstract submission, 4 patients have been accrued. Clinical Trials Reg: NCT02939274

Citation Format: Isakoff SJ, Rogers GS, Hill S, McMullen P, Habin KR, Chen ST, Bartenstein DW, Barry W, Overmoyer BA. An open label, phase II trial of continuous low-irradiance photodynamic therapy (CLIPT) using verteporfin for the treatment of cutaneous breast cancer metastases [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-04-01.

The performance of Luminex ARIES® Flu A/B & RSV and Cepheid Xpert® Flu/RSV XC for the detection of influenza A, influenza B, and respiratory syncytial virus in prospective patient samples

BACKGROUND

The demand for rapid, accurate viral testing has increased the number of assays available for the detection of viral pathogens. One of the newest FDA cleared platforms is the Luminex ARIES^® Flu A/B & RSV, which is a fully automated, real-time PCR-based assay used for detection of influenza A, influenza B, and respiratory syncytial virus (RSV).

OBJECTIVES

We sought to compare the performance of Luminex ARIES^® Flu A/B & RSV assay to the Cepheid Xpert^® Flu/RSV XC assay for rapid Flu and RSV testing.

STUDY DESIGN

A series of consecutive nasopharyngeal specimens received in the clinical microbiology laboratory during peak influenza season at a major academic center in Chicago, IL, were prospectively tested, using both the ARIES^® Flu A/B & RSV and Xpert^® Flu/RSV XC assays, side by side. Discrepant results were tested on the BioFire FilmArray^® Respiratory Panel for resolution.

RESULTS

A total of 143 consecutive nasopharyngeal specimens, obtained from patients ranging from six months to ninety-three years in age were received between January 1st, 2017 and March 21st, 2017. There was 96.6% agreement between the two assays for detection influenza A, 100% agreement for detection influenza B and RSV, and 98.9% agreement for negative results. The Xpert^® Flu/RSV XC performed with an average turn-around time of approximately 60min, compared to the ARIES^® Flu A/B & RSV of approximately 120min. Both assays were equally easy to perform, with a similar amount of hands-on technologist time for each platform.

CONCLUSIONS

Overall, these results indicate that both tests are comparable in terms of result agreement and technical ease-of-use. The Xpert^® Flu/RSV XC assay did produce results with less turn-around-time, approximately 60min quicker than the ARIES^® Flu A/B & RSV.

Prenatal care needs, availability, accessibility, use, and satisfaction: a comparison of military women within and outside the continental United States

This article presents the results of a survey distributed to military women within and outside the continental United States (CONUS and OCONUS) who had received prenatal care and delivered at one of six Army, Navy, or Air Force military facilities. This comparative descriptive study was undertaken to determine from the mothers' perspective (1) their needs, availability, accessibility, use, satisfaction, and preferences for prenatal care services, and (2) if prenatal care and birth outcomes were significantly different for CONUS versus OCONUS women. Both groups reported a high degree of satisfaction with services, clinics/offices, and health care staff. Significant group differences were reported in transportation, length of travel time, and cost of traveling, with the CONUS group reporting greater problems with each. For both groups, quality and consistency of health care were the two most important factors in their preference of provider. More than 20% of the mothers reported receiving no information on some of the common concerns of pregnancy. There were no significant group differences with regard to infant birth weight or length of hospital stay.

Exploration of facilitators and barriers to prenatal care among military women

Early and regular prenatal care has been shown to decrease the incidence of adverse pregnancy outcomes; however, little research has examined it experientially from the mother's perspective. The purpose of this qualitative study was to explore the experience of prenatal care from the military mother's perspective. Using purposive sampling, 16 women who had recently given birth were interviewed. The data were analyzed using a qualitative descriptive research methodology to elicit categories of substantive concepts, ideas, or themes. Data explored in this study included availability, use and satisfaction with prenatal care services, and barriers, preferences, and recommendations.

A guide to understanding informed consent

Anesthesia providers are expected to provide information to the patient during the preanesthesia interview that enables the patient to make informed choices. Adequate disclosure during the informed consent process ensures the equalization of the practitioner/patient relationship and the decision-making rights of the patient. Both certified registered nurse anesthetists (CRNAs) and anesthesiologists are not only legally required to provide information that will allow a patient to make an informed judgment about how to proceed with various anesthetic modalities but are also obligated by their standards of practice. This article informs the CRNA about the principles of informed consent so that they can better understand their role in the informed consent process.

Informed consent: an essential element of safe anesthesia practice

Generally, health care providers have viewed safety in terms of prevention of patient accidents. However, with the growth of patient consumerism and stress on quality improvement, the concept of "safety" has been expanded. This article examines the legal concept of informed consent and offers practical suggestions on increasing both patient and provider safety and improving quality of care. For reasons dictated by statute, case law, and professional ethics, informed consent should be part of the practice of every CRNA. With proper informed consent, misinformation, dissatisfaction, and subsequent legal action can be diminished. Information should be offered to the patient and family and reinforced with written educational materials and instructions. These procedures should be documented in the medical record to provide verification that the patient was informed of the risks and benefits and agreed to the procedure contemplated. Failure to do so could expose the CRNA to legal actions under legal theories that include not only negligence, but battery, and contract as well.