Severe Infectious Complications Research Articles

Assessment of Macrophage Inflammatory Biomarkers and Neutrophil Extracellular Traps Associated Proteins in COVID-19 Patients

▪Background : The SARS-CoV-2 infection activates both innate and adaptive immune responses and induces an exaggerated cytokine storm leading to causes septic shock, acute respiratory distress syndrome, and/or multiple organ failure in critically ill patients. The knowledge of this dysregulated immune response is not well explained. One hypothesis is that the response of macrophages and neutrophils to infection is disproportionate, resulting in overproduction of cytokines and activation of neutrophils leading to the most severe complications of infection, including the production of multiple microthrombi and endothelial damage. Aim of the study: To evaluate the activation levels of macrophage biomarkers as well as indicators of the development of neutrophil extracellular traps (NET) in the first phase of infection in hospitalized patients with COVID19. Patients and Methods: We selected dry blood spot from a total of 60 previously identified SARS-CoV-2 infected subjects. Plasma samples were provided by the Aragon Health System Biobank's collection and were extracted within 5 days of symptom onset. Plasma from 60 healthy controls were used to stablish the control range for NETosis determination. The study was authorized by the Ethics Committee of the Aragon Health System and complies with the European General Data Protection Regulation (GDPR 2016/679) and LO 3/2018. Demographic characteristics, clinical manifestations, follow-up during hospitalization, associated comorbidities, and thrombotic complications were obtained from the database. Chitotriosidase activity (ChT), YKL40 chitinase and CCL18/PARC cytokine were measured as markers of macrophage activation. Myeloperoxidase (MPO), Neutrophil Elastase (NE), and S100A8/S100A9 Heterodimer (MPR) were immuno-quantified, levels of circulating free DNA (cfDNA) were measured as well as the presence of DNAsases by fluorimetry as indicators of Netosis. For the comparative analysis, we stratified patients by age groups and disease severity and used the Mann-Whitney U test for statistical comparison, considering a p-value < 0.05 as statistically significant. Results : A statistically significant increase in ChT (p=0.032) and CCL18/PARC (p=0.0001) was observed in the patients´ group. A comparative study with clinical variables and other inflammation markers as ferritin, D-dimer will be shown upon acceptance. Concerning NET markers, we found a statistically significant increase in MPO, NE, and MRP in COVID-19 patients (p=0.0001; p=0.0290; p=0.0001 respectively), as well as a statistically significant decrease in DNAsa (p=0.0001). No differences in cfDNA levels were observed. The table shows the median (quartile1-quartile3) for each marker in the control group and in the patient group. Conclusions : In this study, biomarkers of macrophage activation do not appear to be more sensitive than the indicators of inflammation in routine clinical practice (ferritin, D-dimer). Clinical cases of severe COVID-19 disease show an excessive NET formation, which contributes to vascular damage and the development of thrombosis.This work was supported by a research grant from FEETEG [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Orca-T Results in High Gvhd-Free and Relapse-Free Survival Following Myeloablative Conditioning for Hematological Malignancies: Results of a Single Center Phase 2 and a Multicenter Phase 1b Study

Orca-T Results in High Gvhd-Free and Relapse-Free Survival Following Myeloablative Conditioning for Hematological Malignancies: Results of a Single Center Phase 2 and a Multicenter Phase 1b Study

MYELOPEROXIDASE DEFICIENCY: SINGLE CENTER EXPERIENCE

Myeloperoxidase (MPO) is a hemoprotein expressed in azurophilic granules of neutrophils and lysosomes of monocytes. It is caused by mutations in the MPO gene on chromosome 17 and is estimated to affect 1:2000-4000 people. It is the most common inherited defect of phagocytes. Microbial killing is impaired in patients with MPO deficiency, but most patients are asymptomatic, except for diabetic patients. In this article, we aimed to present our patients diagnosed with primary MPO deficiency. During the investigation for the etiology of neutropenia in the hematology department of our hospital, patients who were diagnosed with MPO deficiency were examined. In the evaluation of the patients, it was observed that the neutrophil count in the hemogram printout and the counted neutrophil count in the peripheral smear were inconsistent. We performed MPO staining with FCM from the peripheral blood samples of the patients and we found that the neutrophils were MPO negative. A 1-day-old male patient has no additional disease (c.608A&gt;C H mutation). C.578G&gt;C mutation was detected in the follow-up due to ANA+ in a 6.5-year-old female patient. A c.2031-2A&gt;C mutation was found in the 18-year-old patient who was being followed up with the diagnosis of Granulamatous Polyangiitis and his sister. A c.493del mutation was detected in an 11-year-old patient who was diagnosed with ITP 5 years ago. The noval mutation was detected in the patient followed up with the diagnosis of retinoblastoma. MPO deficiency may occur primarily as well as secondary. A number of point germ line mutations cause primary MPO deficiency. Most patients asymptomatic without an increase in infection. Severe infectious complications were not observed in any of our patients. We wanted to emphasize that MPO deficiency should also be kept in mind in patients whose neutropenia etiology was investigated.

Long-term moderate to severe complications of COVID-19 infection since 2019 to date

Abstract Objective: To investigate the long-term complications in patients recovered from coronavirus disease 2019 (COVID-19) infection. Methods: We will perform a meta-analysis and will search multiple electronic databases (PubMed, Scopus, Cochrane library) with predefined search terms to identify eligible articles. Eligible studies should report long-term complications of COVID-19 infection worldwide. Case reports, case series, observational studies with cross-sectional or prospective research design, case-control studies, and experimental studies will be included. Study quality will be evaluated by two reviewers independently using the statistical methodology and categories guided by the Cochrane Collaboration Handbook and PRISMA guidelines. Results: This study will explore and integrate the evidence available on the long-term complications of COVID-19 infection in various organ systems. Conclusion: By acquiring and statistically analyzing the data about these complications, this study will generate an extensive knowledge on the topic for a better management of the post pandemic healthcare related to COVID-19.

Immunosuppressors and immunomodulators in Neurology - Part I: a guide for management of patients underimmunotherapy.

For patients with autoimmune diseases, the risks and benefits of immunosuppressive or immunomodulatory treatment are a matter of continual concern. Knowledge of the follow-up routine for each drug is crucial, in order to attain better outcomes and avoid new disease activity or occurrence of adverse effects. To achieve control of autoimmune diseases, immunosuppressive and immunomodulatory drugs act on different pathways of the immune response. Knowledge of the mechanisms of action of these drugs and their recommended doses, adverse reactions and risks of infection and malignancy is essential for safe treatment. Each drug has a specific safety profile, and management should be adapted for different circumstances during the treatment. Primary prophylaxis for opportunistic infections and vaccination are indispensable steps during the treatment plan, given that these prevent potential severe infectious complications. General neurologists frequently prescribe immunosuppressive and immunomodulatory drugs, and awareness of the characteristics of each drug is crucial for treatment success. Implementation of a routine before, during and after use of these drugs avoids treatment-related complications and enables superior disease control.

State-of-the-art surgery for sigmoid diverticulitis

SummaryBackgroundIn the last two decades, there has been a Copernican revolution in the decision-making for the treatment of Diverticular Disease.PurposeThis article provides a report on the state-of-the-art of surgery for sigmoid diverticulitis.ConclusionAcute diverticulitis is the most common reason for colonic resection after cancer; in the last decade, the indication for surgical resection has become more and more infrequent also in emergency. Currently, emergency surgery is seldom indicated, mostly for severe abdominal infective complications. Nowadays, uncomplicated diverticulitis is the most frequent presentation of diverticular disease and it is usually approached with a conservative medical treatment. Non-Operative Management may be considered also for complicated diverticulitis with abdominal abscess. At present, there is consensus among experts that the hemodynamic response to the initial fluid resuscitation should guide the emergency surgical approach to patients with severe sepsis or septic shock. In hemodynamically stable patients, a laparoscopic approach is the first choice, and surgeons with advanced laparoscopic skills report advantages in terms of lower postoperative complication rates. At the moment, the so-called Hartmann’s procedure is only indicated in severe generalized peritonitis with metabolic derangement or in severely ill patients. Some authors suggested laparoscopic peritoneal lavage as a bridge to surgery or also as a definitive treatment without colonic resection in selected patients. In case of hemodynamic instability not responding to fluid resuscitation, an initial damage control surgery seems to be more attractive than a Hartmann’s procedure, and it is associated with a high rate of primary anastomosis.

Extrapulmonary manifestations and complications of severe acute respiratory syndrome coronavirus-2 infection: a systematic review.

We aimed to describe the extrapulmonary manifestations of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection, including their frequency, onset with respect to respiratory symptoms, pathogenesis and association with disease severity. We searched the MEDLINE and Embase databases for SARS-CoV-2-related studies. Meta-analysis, observational studies, case series and case reports published in English or Chinese between 1 January 2020 and 1 May 2020 were included. Reports with only paediatric or obstetric cases were excluded. 169 articles were included. Early manifestations (preceding respiratory symptoms until Day 6 of onset) included olfactory and gustatory disturbance (self-reported in up to 68% and 85% of cases, respectively), gastrointestinal symptoms (up to 65.9%) and rash (up to 20.4%). From Day 7 onwards, hypercytokinaemia, paralleled multi-organ complications including acute cardiac injury (pooled incidence of 17.7% in 1,412 patients, mostly with severe disease and 17.4% mortality), kidney and liver injury (up to 17% and 33%, respectively) and thrombocytopenia (up to 30%). Hypercoagulability resulted in venous thromboembolic events in up to 31% of all patients. Uncommon disease presentation and complications comprised Guillain-Barré syndrome, rhabdomyolysis, otitis media, meningoencephalitis and spontaneous pneumomediastinum. Although the systemic manifestations of SARS-CoV-2 infection are variegated, they are deeply interwoven by shared mechanisms. Two phases of extrapulmonary disease were identified: (a) an early phase with possible gastrointestinal, ocular and cutaneous involvement; and (b) a late phase characterised by multiorgan dysfunction and clinical deterioration. A clear, multidisciplinary consensus to define and approach thromboinflammation and cytokine release syndrome in SARS-CoV-2 is needed.

CASE REPORT: COMPLICATION AT BOTH RECEIVING AND DONOR SITES IN FACIAL AUTOLOGOUS FAT TRANSFER

Autologous fat grafting is a technique that has been used for a long time in the field of plastic surgery. Besides many advantages, the complications, which can range from mild such as hematoma, infection, calcification, necrosis... even death is a big problem. The article presents a case of using autologous fat taken from the abdomen to graft onto the facial area with complications of severe infection in both the receiving and donor sites, causing necrosis of fat and skin in both areas. The treatment takes a long time with different procedures, but the consequences for the patient are still very serious both in terms of aesthetics and function. The objective of this study was to evaluate the safety and efficacy of fat grafting to the facial region for the reconstruction and aesthetic enhancement of facial contour.

Astaxanthin protective barrier and its ability to improve the health in patients with COVID-19.

Inflammation acts like a double-edged sword and can be harmful if not appropriately controlled. COVID-19 is created through a novel species of coronavirus SARS-CoV-2 (2019-nCoV). Elevated levels of inflammatory factors such as interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), etc. lead to Acute Respiratory Distress Syndrome (ARDS) and severe complications of infection in the lungs of coronavirus-infected patients. Astaxanthin is a natural and potent carotenoid with powerful antioxidant activity as well as an anti-inflammatory agent that supports good health. The effects of astaxanthin on the regulation of cyclooxygenase-2 (COX-2) pathways and the reduction and suppression of cytokines and other inflammatory agents such as IL-6 and TNF-α have already been identified. Therefore, these unique features can make this natural compound an excellent option to minimize inflammation and its consequences.

Establishment of CORONET: COVID-19 Risk in Oncology Evaluation Tool to Identify Cancer Patients at Low Versus High Risk of Severe Complications of COVID-19 Infection Upon Presentation to Hospital

Establishment of CORONET: COVID-19 Risk in Oncology Evaluation Tool to Identify Cancer Patients at Low Versus High Risk of Severe Complications of COVID-19 Infection Upon Presentation to Hospital

Treatment of severe infectious complications caused by multidrug-resistant Klebsiella pneumoniae in children with malignant neoplasms of the hematopoietic system: experience of the Research Institute of Pediatric Oncology and Hematology at N.N. Blokhin Russian Cancer Research Center

Introduction. So far there has been no clear protocol on the treatment of bacterial infections in hematopoietic cancer patients undergoing polychemotherapy (PCT) and hematopoietic stem cell transplantation (HSCT). Guidelines available from antibiotic therapy panels such as EMBT, NCCN, ECIL, Sepsis-3 often fail to cover the entire spectrum of clinical risk factors of severe complications caused specifically by multiresistant Klebsiella pneumoniae.The aim of the study — is to showcase the clinical experience of demonstration of the experience of the Research Institute of Pediatric Oncology and Hematology at N.N. Blokhin Russian Cancer Research Center with respect to adjusting antibacterial therapy for the spectrum of microorganisms found in the patient before the onset of antitumor therapy, and for the multiresistant microorganism findings in patients with blood cancers and febrile neutropenia (FN) undergoing PCT and HSCT.Materials and methods. The study involved five patients undergoing either PCT or HSCT for hematopoietic cancers at Research Institute of Pediatric Oncology and Hematology in October 2019 — October 2020, multiresistant Klebsiella pneumonia colonies found in each case. Results. Five patients with hematopoietic cancers and induced bone marrow aplasia were found to have multiresistant Klebsiella pneumoniae colonies on top of post-PCT/HSCT immunosuppression. Given high risk of death, these patients need early antibacterial therapy with reserve antibiotics outside standard empirical antibacterial treatment protocols should they develop FN. The Center's practices have shown that baseline protocols are often inadequate to the severity of these patients' conditions in a certain timeframe.Conclusions. To sum up the Center's limited experience, the finding is that additional research is required into the factors of risk of severe multiresistant Klebsiella pneumoniae infections in patients undergoing PCT and HSCT; algorithms must be developed for the treatment of patients in such a critical condition.

Retinal Microcirculation as a Correlate of a Systemic Capillary Impairment After Severe Acute Respiratory Syndrome Coronavirus 2 Infection.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which causes coronavirus disease 2019 (COVID-19), affects the pulmonary systems via angiotensin-converting enzyme-2 (ACE-2) receptor, being an entry to systemic infection. As COVID-19 disease features ACE-2 deficiency, a link to microcirculation is proposed. Optical coherence tomography angiography (OCT-A) enables non-invasive analysis of retinal microvasculature. Thus, an impaired systemic microcirculation might be mapped on retinal capillary system. As recent OCT-A studies, analyzing microcirculation in two subdivided layers, yielded contrary results, an increased subdivision of retinal microvasculature might offer an even more fine analysis. The aim of the study was to investigate retinal microcirculation by OCT-A after COVID-19 infection in three subdivided layers (I). In addition, short-term retinal affections were monitored during COVID-19 disease (II). Considering (I), a prospective study (33 patientspost−COVID and 28 controls) was done. Macula and peripapillary vessel density (VD) were scanned with the Spectralis II. Macula VD was measured in three layers: superficial vascular plexus (SVP), intermediate capillary plexus (ICP), and deep capillary plexus (DCP). Analysis was done by the EA-Tool, including an Anatomical Positioning System and an analysis of peripapillary VD by implementing Bruch's membrane opening (BMO) landmarks. Overall, circular (c1, c2, and c3) and sectorial VD (s1-s12) was analyzed. Considering (II), in a retrospective study, 29 patients with severe complications of COVID-19 infection, hospitalized at the intensive care unit, were monitored for retinal findings at bedside during hospitalization. (I) Overall (p = 0.0133) and circular (c1, p = 0.00257; c2, p = 0.0067; and c3, p = 0.0345). VD of the ICP was significantly reduced between patientspost−COVID and controls, respectively. Overall (p = 0.0179) and circular (c1, p = 0.0189) peripapillary VD was significantly reduced between both groups. Subgroup analysis of hospitalized vs. non-hospitalized patientspost−COVID yielded a significantly reduced VD of adjacent layers (DCP and SVP) with increased severity of COVID-19 disease. Clinical severity parameters showed a negative correlation with VD (ICP) and peripapillary VD. (II) Funduscopy yielded retinal hemorrhages and cotton wool spots in 17% of patients during SARS-CoV-2 infection. As VD of the ICP and peripapillary regions was significantly reduced after COVID-19 disease and showed a link to clinical severity markers, we assume that the severity of capillary impairment after COVID-19 infection is mapped on retinal microcirculation, visualized by non-invasive OCT-A.

Cangrelor ameliorates CLP-induced pulmonary injury in sepsis by inhibiting GPR17

BackgroundSepsis is a common complication of severe wound injury and infection, with a very high mortality rate. The P2Y12 receptor inhibitor, cangrelor, is an antagonist anti-platelet drug.MethodsIn our study, we investigated the protective mechanisms of cangrelor in CLP-induced pulmonary injury in sepsis, using C57BL/6 mouse models.ResultsTdT-mediated dUTP Nick-End Labeling (TUNEL) and Masson staining showed that apoptosis and fibrosis in lungs were alleviated by cangrelor treatment. Cangrelor significantly promoted surface expression of CD40L on platelets and inhibited CLP-induced neutrophils in Bronchoalveolar lavage fluid (BALF) (p < 0.001). We also found that cangrelor decreased the inflammatory response in the CLP mouse model and inhibited the expression of inflammatory cytokines, IL-1β (p < 0.01), IL-6 (p < 0.05), and TNF-α (p < 0.001). Western blotting and RT-PCR showed that cangrelor inhibited the increased levels of G-protein-coupled receptor 17 (GPR17) induced by CLP (p < 0.001).ConclusionOur study indicated that cangrelor repressed the levels of GPR17, followed by a decrease in the inflammatory response and a rise of neutrophils in BALF, potentially reversing CLP-mediated pulmonary injury during sepsis.

Effectiveness of Supportive Care Measurements to Reduce Infections during Induction for Children with Acute Myeloid Leukemia: A Report from the Japanese Pediatric Leukemia/Lymphoma Study Group (JPLSG)

BACKGROUNDCurrent intensive chemotherapy for pediatric acute myeloid leukemia (AML) in conjunction with supportive care has increased survival rate up to 70%, and yet infections are still responsible for considerable morbidity and most treatment-related deaths. These factors have led to much interest in supportive care measurements to reduce infections and infectious mortality. The Japanese Pediatric Leukemia/Lymphoma Study Group (JPLSG) trial AML-05 was a phase 2 study that included children with de novo AML treated with intensive chemotherapy. We surveyed participating JPLSG sites to assess the effect of each supportive care measurements on Induction I infection risk and non-relapse mortality for children in AML-05 study. METHODSBetween November 2006 and December 2010, JPLSG AML-05, registered at http://www.umin.ac.jp/ctr/ as UMIN000000511, recruited 447 eligible children (age <18 years) with de novo AML. AML-05 used 5 courses of intensive chemotherapy with Induction I consisting of etoposide 150mg/m2/dose intravenous (IV) every 24 h on day 1-5; cytarabine 200 mg/m2/dose intravenous (IV) every 12 h on days 6-12; mitoxantrone 5 mg/m2/dose IV on days 6-10; triple intrathecal treatment (methotrexate/ cytarabine/ hydrocortisone) (ECM 5+7+5). Data of Infectious complications were collected prospectively and monitored in real-time to optimize reporting accuracy. In this analysis, infectious events were limited to Induction I. Non-relapse mortality was defined as any induction death within 40 days of being taken off study due to non-disease related causes. The survey included questions on implementations in each patient participated in AML-05 study for antibacterial prophylaxis, antifungal prophylaxis, intestinal sterilization, use of HEPA-filter, surveillance culture, and use of G-CSF until count recovery. RESULTSThe survey response rate from the JPLSG sites was 359/447 (80.3%). In multiple regression, anti-bacterial prophylaxis reduced the development of febrile neutropenia during induction chemotherapy (Odds ratio [OR] 0.56, 95% confidence interval [CI] 0.39-0.88; p = 0.013). Sterile site bacterial infections increased in younger age group (OR 2.0, 95% CI, 1.09-3.66; p = 0.025) but decreased in patients who were routinely carried out surveillance culture (OR 0.5, 95% CI, 0.27-0.96; p = 0.038). Fungal infection during induction chemotherapy was associated with intestinal sterilization (OR 0.21, 95% CI, 0.61-0.70; p = 0.011) and the use of G-CSF (OR 3.83, 95% CI, 1.10-13.32; p = 0.035). Prophylactic antifungal agent had a tendency to reduce the frequency and duration of pyrexia, and the peak value of CRP. Nonetheless, routine prophylaxis with these agents did not impact non-relapse mortality. CONCLUSIONSProphylactic use of antibiotics was associated with less development of febrile neutropenia. Routine prophylaxis with these agents may be associated with incidence and severity of infectious complications, but did not impact non-relapse mortality during induction chemotherapy in childhood AML. DisclosuresNo relevant conflicts of interest to declare.

Ruxolitinib Inhibits Toll-like Receptor or GM-CSF, but Not TREM-1 Mediated Neutrophil Activation

Introduction: Ruxolitinib (RUX) is the first Janus kinase (JAK)1/2 inhibitor approved for the treatment of myelofibrosis (MF) or polycytemia vera (PV), as the pathogenesis of these myeloproliferative neoplasms is linked to a dysregulation of JAK signaling. In clinical trials, RUX demonstrates a profound reduction of splenomegaly and constitutive symptoms along with an improved quality of life. The most frequent adverse events of RUX include anemia and thrombocytopenia. However, beyond this, severe infectious complications have been reported in association with RUX treatment, such as C. neoformans pneumonia, toxoplasmosis retinitis and hepatitis B virus reactivation, indicating immunosuppressive effects of this drug. On the cellular level, RUX has yet been characterized as a negative regulator for NK- and T-cell functions, possibly accounting for the side effects observed. In our present work, we focused on the impact of RUX on polymorphonuclear neutrophil (PMN) activation as important regulators of the innate immune response.Methods: Purified PMN from healthy human donors were isolated by dextran sedimentation and HistopaqueÒ centrifugation and pretreated with RUX. PMN were activated with anti-TREM-1 agonistic antibody (6B1), isotope matched control antibody (4C9) (both own production), lipopolysaccharide (LPS), zymosan or GM-CSF and effector functions like phagocytosis by fluorochrome labeled polystyrene beads, L-selectin (CD62L) shedding, oxidative burst and IL-8 secretion were analyzed. In addition, blood samples of patients under RUX treatment and samples of age matched healthy volunteers were stimulated either with GM-CSF, LPS or zymosan. Afterwards functionality of PMN was analyzed by determination of oxidative burst, phagocytosis, L-selectin shedding and degranulation.Results: Ligation of TREM-1 (by specific antibody), TLR2/6 (by zymosan), TLR4 (by LPS) or GM-CSF-R induced a strong activation of PMN derived from healthy human donors, as shown by initiation of oxidative burst, increased phagocytic activity as well as CD62L shedding and release of IL-8. The additional presence of RUX revealed an impaired phagocytosis, CD62L shedding and IL-8 production after activation with the TLR agonists (LPS, zymosan) or GM-CSF, whereas no profound impact of pretreatment was observed on TREM-1 mediated effector functions. These results suggest that the inhibition of JAK signaling affects TLR and GM-CSF mediated PMN activation, while this particular pathway appears functionally irrelevant for TREM-1 mediated PMN activation. In line with these results, we observed impaired PMN functions in patients receiving RUX treatment compared to healthy controls with the most impressive impact on the oxidative burst and phagocytosis after LPS or zymosan stimulation.Conclusion: These data provide deeper insights on the impact of RUX as an immunosuppressant of innate immunity on the cellular level adding the selective inhibition of distinct PMN activating receptor pathways. The observation of impaired effector functions of PMN after RUX pretreatment in vitro as well as in vivo may help to explain the severe infectious complications accompanying MF or PV. DisclosuresKindler:Novartis: Membership on an entity's Board of Directors or advisory committees. Radsak:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Gilead: Other: Travel support; Acceleron: Research Funding.

Idelalisib Impairs TREM-1 Mediated Neutrophil Inflammatory Responses

Introduction: Idelalisib is a selective PI3Kδ inhibitor approved for B-cell non-Hodgkin lymphoma (B-NHL). As adverse events recurrent and severe infectious complications have been observed and experimental data suggest an influence on innate immune defense. Since PI3K is involved in signal transduction of triggering receptor expressed on myeloid cells (TREM)-1, an activating receptor on polymorphonuclear neutrophils (PMN) and macrophages that is implicated in innate immune activation of these cells, we asked, whether PMN function might be impaired by this small-molecule inhibitor.Methods: PMN from healthy humans were isolated by dextran sedimentation and density gradient centrifugation and pretreated with idelalisib, selective PI3Kα/-β/-γ inhibitors (all 1 µg/ml) or vehicle control (DMSO). Cells were activated with anti-TREM-1 agonistic antibody, an isotype matched control antibody (both own production) or Toll-like receptor 4 (TLR4) agonist lipopolysaccharide (LPS, 1 µg/ml). Effector functions were evaluated by analyzing phagocytosis, CD62L shedding, degranulation and oxidative burst by flow cytometry or oxidative burst kinetics in a fluorescence reader, respectively. Interleukin-8 (IL-8) release was detected by ELISA. Western blot analyses of phosphorylated and non-phosphorylated proteins were used for the detection of the involved signaling events, and calcium flux was detected by flow cytometry. Similarly, blood samples of patients receiving idelalisib treatment were followed up for PMN functions as described above to investigate immunomudulatory effects in vivo .Results: We observed a significantly impaired oxidative burst, degranulation (CD66b and CD11b surface expression), CD62L shedding and cytokine (IL-8) release upon PMN activation via TREM-1 ligation and partly by LPS. Furthermore, TREM-1 mediated calcium flux was diminished and TREM-1 signaling was impaired regarding phosphorylation of p38MAPK, ERK1/2 and AKT indicating that the activation of Ca2+ flux as well as MAP kinases and AKT occur down stream of PI3K. Selective PI3Kα and PI3Kβ inhibitors (but not a PI3Kγ inhibitor) showed similar activation patterns, furthermore suggesting that impaired PMN functionalities are due to an unspecific PI3K class IA inhibitory effect. To assess whether our results obtained in vitro may be of relevance in vivo, we analyzed blood samples of B-NHL patients receiving idelalisib therapy ex vivo. Here we again detected an impairment of TREM-1 mediated and partly of TLR4 mediated PMN activation. PMN functions from one patient were analyzed during and after idelalisib therapy. Interestingly, PMN functions were restored after discontinuation of treatment, indicating that the functional PMN deficiencies are reversible.Conclusion: Small-molecule inhibitors might cause a neutropenia-like susceptibility to infections in patients by leading to impaired PMN functions. These side effects are largely unrecognized in daily clinical routine so far by monitoring just for counts of white blood cells, but not their functions. DisclosuresTeschner:Astellas Pharma GmbH: Other: Travel support; Gilead Sciences GmbH: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Jazz Pharmaceuticals Germany: Other: Travel Support; MSD Sharp & Dohme GmbH: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Pfizer Deutschland GmbH: Honoraria, Membership on an entity's Board of Directors or advisory committees. Hess:Celgene: Other: Grants and personal fees; Pfizer: Other: Grants and personal fees; CTI: Other: Grants; Roche: Other: Grants and personal fees; Janssen: Other: Personal Fees. Radsak:Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support, Research Funding; Novartis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel support; Gilead: Other: Travel support; Acceleron: Research Funding.

Induction Chemo-Immunotherapy with the Matrix Regimen in Patients with Newly Diagnosed PCNSL - a Multicenter Retrospective Analysis on Feasibility and Effectiveness in Routine Clinical Practice

▪BackgroundThe randomized IELSG32 trial compared 3 different induction chemo(immuno)therapy combinations in patients with newly diagnosed primary CNS lymphoma (PCNSL). Results showed that the MATRix combination (methotrexate [MTX], cytarabine [AraC], thiotepa, and rituximab) followed by consolidation therapy significantly improved outcomes in patients up to the age of 70 years (Ferreri et al. Lancet Haematol 2016; Ferreri et al. ASH abstract 2016). The MATRix protocol (4 cycles repeated every 3 weeks) followed by consolidation high dose chemotherapy and autologous stem cell transplant (HDT-ASCT) or whole-brain radiotherapy (WBRT) is now widely regarded as a new treatment standard and benchmark for future randomized trials. However, treatment associated toxicity is common, and many patients encountered in routine practice are older/frailer than those treated in the IELSG32 trial. We conducted a retrospective multicenter study of clinical outcomes in newly diagnosed PCNSL patients treated with MATRix in routine clinical care.MethodsThis retrospective cohort included all consecutive patients with newly diagnosed PCNSL who received at least 1 cycle of MATRix chemotherapy in a real-world non-trial setting between 2010 and 2017 at 9 European centers. One cycle consisted of: 2 x rituximab 375 mg/m² before and/or after chemotherapy, MTX 3.5 mg/m² on day 1, AraC 2 g/m² twice daily on days 2 and 3, and thiotepa 30 mg/m² on day 4. Patients were enrolled at the discretion of the treating physician. Main endpoints were theoretical eligibility for the IELSG32 trial, rate of (serious) adverse events, feasibility, remission status after MATRix therapy, progression free survival (PFS) and overall survival (OS).Results88 patients were included, with a median age of 61 years (range 28-76). Twenty-three patients (26%) would not have met the inclusion criteria of the IELSG32 trial (age > 70 years: 10; reduced performance status [PS]: 4; HIV infection: 3; active hepatitis: 3; inadequate organ function: 3). Anticipated treatment courses were delivered in 228/352 (65%) cases. Dose modifications were performed in 35/88 patients (40%) during cycle 1, in 43/79 patients (54%) during cycle 2, in 33/70 patients (47%) during cycle 3, and in 29/57 patients (51%) during cycle 4. The most common reasons for chemotherapy modification during cycle 1 were reduced PS, co-existing comorbidities and age. Main reasons for dose reduction during subsequent chemotherapy cycles were hematological toxicities, infectious complications and reduced performance. Adverse events, mainly infections, were reported in 48/88 patients (55%) during cycle 1, in 39/79 patients (49%) during cycle 2, in 33/70 patients (47%) during cycle 3, and in 22/57 patients (39%) during cycle 4. Severe infectious complications were more common during cycle 1 (16%) compared to cycle 4 (5%). Intensive care support was required in 4/88 patients (4.5%) during cycle 1, in 1/79 patients (1%) during cycle 2, in 1/70 patients (1.5%) during cycle 3, and in no patients during cycle 4. We recorded six (7%) treatment related deaths during induction chemotherapy (4 during cycle 1, 2 during cycle 2; median patient age 65 years; range 54-75), 5 due to infectious complications and one due to sudden death. Two other patients died later (over 1 year after initiation of MATRix treatment thus not considered treatment related) whilst off therapy and without evidence of disease (one due to hepatic failure and another due to septic encephalitis). After a median of 4 MATRix cycles (range 1-4), the overall response rate was 83% (41% complete remission, 42% partial remission). Nine patients (11%) had progressive disease. Consolidation therapy was applied in 44/82 patients (54%) after MATRix induction therapy (HDT-ASCT: 35; WBRT: 8; lenalidomide: 1). After a median follow-up of 13.1 months, 2-year OS and PFS was 64% (95% CI 52% to 80%) and 57% (95% CI 45% to 72%).ConclusionsThe MATRix protocol is feasible and effective in the treatment of newly diagnosed PCNSL in routine practice, and can be delivered to patients aged >70, with reduced PS and/or co-morbidity to produce similar clinical outcomes to the IELSG32 trial. Importantly, close monitoring and consideration of dose reductions is strongly recommended, especially during cycle 1, to avoid treatment associated complications. Further details will be presented at the meeting. DisclosuresSchorb:Riemser: Honoraria. Fox:Janssen: Consultancy, Honoraria, Other: Travel Sponsorship, Speakers Bureau; Roche: Consultancy, Honoraria, Other: Travel Sponsorship, Research Funding, Speakers Bureau; AbbVie: Consultancy, Honoraria, Other: Travel Sponsorship, Research Funding. Yallop:Jazz Pharmaceuticals: Honoraria; Pfizer: Other: Advisory board; Amgen: Honoraria. Cummin:Janssen: Other: Travel reimbursement. Illerhaus:Riemser: Honoraria. Cwynarski:Gilead, Roche: Other: Advisory board; Gilead, Janssen: Other: Conference expenses.

The PI3K\u03b4 inhibitor idelalisib impairs the function of human dendritic cells

The PI3Kδ-inhibitor Idelalisib is approved for the treatment of Non-Hodgkin lymphoma. However, its use has been decreased within the last years due to deleterious infections such as cytomegalovirus and pneumocystis jirovecii. Here, we have investigated the effect of Idelalisib on human monocyte-derived dendritic cells (DCs) as important players in the induction of immune responses. We found that Idelalisib-treated DCs displayed impaired T cell stimulatory function. PI3Kδ inhibition during differentiation resulted in decreased Interleukin-12, Interleukin-13 and TNFα production by DCs after lipopolysaccharide stimulation. Moreover, DCs showed decreased expression of the activation marker CD83 after Idelalisib treatment. Further, in line with this was the failure of Idelalisib-treated DCs to properly induce allogeneic T cells in a dose-dependent manner. Finally, activation of the NFκB pathway was also ablated in Idelalisib-treated DCs. Our results implicate that severe infectious complications may not only result from direct PI3Kδ-inhibition in T cells, but also from impaired DC function in Idelalisib-treated patients. Here, we provide new insight into the pathogenesis of Idelalisib-associated infectious complications. Our study may further provide a rationale for the use of Idelalisib as a novel therapeutic option in inflammatory diseases.

Monoprophylaxis With Cephalosporins for Transrectal Prostate Biopsy After the Fluoroquinolone-Era: A Multi-Institutional Comparison of Severe Infectious Complications.

BackgroundTo compare severe infectious complication rates after transrectal prostate biopsies between cephalosporins and fluoroquinolones for antibiotic monoprophylaxis.Material and MethodsIn the multi-institutional cohort, between November 2014 and July 2020 patients received either cefotaxime (single dose intravenously), cefpodoxime (multiple doses orally) or fluoroquinolones (multiple-doses orally or single dose intravenously) for transrectal prostate biopsy prophylaxis. Data were prospectively acquired and retrospectively analyzed. Severe infectious complications were evaluated within 30 days after biopsy. Logistic regression models predicted biopsy-related infectious complications according to antibiotic prophylaxis, application type and patient- and procedure-related risk factors.ResultsOf 793 patients, 132 (16.6%) received a single dose of intravenous cefotaxime and were compared to 119 (15%) who received multiple doses of oral cefpodoxime and 542 (68.3%) who received fluoroquinolones as monoprophylaxis. The overall incidence of severe infectious complications was 1.0% (n=8). No significant differences were observed between the three compared groups (0.8% vs. 0.8% vs. 1.1%, p=0.9). The overall rate of urosepsis was 0.3% and did not significantly differ between the three compared groups as well.ConclusionMonoprophylaxis with third generation cephalosporins was efficient in preventing severe infectious complications after prostate biopsy. Single intravenous dose of cefotaxime and multiday regimen of oral cefpodoxime showed a low incidence of infectious complications <1%. No differences were observed in comparison to fluoroquinolones.

Mixed Nervous System Involvement in a Child with Multisystem Inflammatory Syndrome- A Rare Presentation of SARS-CoV-2

Multi-system inflammatory syndrome (MIS-C) is a rare but severe complication of Covid-19 infection. The clinical presentation ranges from a mild course of systemic inflammatory response to a life threatening hyper inflammatory shock and multi organ dysfunction. Central nervous system presentation is seen in acute Covid-19 infection in adults but is rarely seen in children. We describe a case of MIS-C in a child who was admitted to our Pediatric Intensive Care Unit with features of hyper inflammatory syndrome and mixed central and peripheral nervous system manifestations.