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A 71-year-old man complained of a blackish wound under his left eye, which began with fever and reddish spots after helping to slaughter a cow and cut its meat. The fever occured especially in the afternoon to evening, and is not accompanied by chills and sweating. On day 4 of fever onset, the fever diminished and the spots progressively widened with swelling. On day 7, the lesions on the skin became open wounds that were not purulent and did not bleed. On day 9, a blackish, painless layer appeared over the wounds and widened, further covering their surface. Upon presentation, the patient's general condition was good, with normal vital signs and temperature. He presented with a solitary ulcer accompanied by edema, sized 1 cm x 3 cm, not hyperemic, firm border, flat edge, and covered with blackish eschar. Blood tests revealed normal levels of hemoglobin, leukocyte, platelets, kidney and liver function. The anti-anthrax protective antigen (anti-PA) IgG level is found to be seropositive with a level of 85 U/ml. Gram staining of the tissue underneath the eschar found Gram-positive rod bacteria in reddish-purple color. The patient was clinically diagnosed with probable cutaneous anthrax, and was treated with amoxicillin 500 mg orally t.i.d. for three days and paracetamol 500 mg if fever developed. The tissue sample was sent to a laboratory with Bio Safety level 3 facilities for microbiological culture, with the results of Bacillus anthracis growth. On day three after antibiotic administration, the wound was smaller (0.5 cm x 1.5 cm), firm border, flat edge, with a bit of edema above it. The eschar was thickened, painless, not purulent nor bleeding. Antibiotic administration is continued for another three days with amoxicillin 500 mg orally t.i.d. On day 6 of antibiotic administration, the eschar began to peel off, and antibiotics were stopped. On the 10th day, the eschar peeled off entirely without leaving a mark. Early diagnosis is crucial in preventing the spread that may lead to more cases. Clinical and serological examinations are the spearheads of early detection of anthrax cases. Prompt and appropriate management largely determines the success of therapy.

Background: The immunopathogenesis of dengue virus (DENV) infection remains incompletely understood. To increase our understanding of inflammatory response in non-severe dengue, we assessed longitudinal changes in the inflammatory proteome in patients with an acute DENV infection., Methods: Using a multiplex proximity extension assay (PEA), we measured relative levels of 368 inflammatory markers in plasma samples from hospitalized patients with non-severe DENV infection in the acute (n = 43) and convalescence (n = 35) phase of the infection and samples of healthy controls (n = 10)., Results: We identified 203 upregulated and 39 downregulated proteins in acute versus convalescent plasma samples. The upregulated proteins had a strong representation of interferon (IFN) and IFN-inducible effector proteins, cytokines (e.g. IL-10, IL-33) and cytokine receptors, chemokines, pro-apoptotic proteins (e.g. granzymes) and endothelial markers. A number of differentially expressed proteins (DEPs) have not been reported in previous studies. Functional network analysis highlighted a central role for IFNγ, IL-10, IL-33 and chemokines. We identified different novel associations between inflammatory proteins and circulating concentrations of the endothelial glycocalyx disruption surrogate marker syndecan-1. Conclusion: This unbiased proteome analysis provides a comprehensive insight in the inflammatory response in DENV infection and its association with glycocalyx disruption., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Garishah et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Previous studies have shown that monocytes can be 'trained' or tolerized by certain stimuli to respond stronger or weaker to a secondary stimulation. Rewiring of glucose metabolism was found to be important in inducing this phenotype. As we previously found that Borrelia burgdorferi (B. burgdorferi), the causative agent of Lyme borreliosis (LB), alters glucose metabolism in monocytes, we hypothesized that this may also induce long-term changes in innate immune responses. We found that exposure to B. burgdorferi decreased cytokine production in response to the TLR4-ligand lipopolysaccharide (LPS). In addition, B. burgdorferi exposure decreased baseline levels of glycolysis, as assessed by lactate production. Using GWAS analysis, we identified a gene, microfibril-associated protein 3-like (MFAP3L) as a factor influencing lactate production after B. burgdorferi exposure. Validation experiments proved that MFAP3L affects lactate- and cytokine production following B. burgdorferi stimulation. This is mediated by functions of MFAP3L, which includes activating ERK2 and through activation of platelet degranulation. Moreover, we showed that platelets and platelet-derived factors play important roles in B. burgdorferi-induced cytokine production. Certain platelet-derived factors, such chemokine C-X-C motif ligand 7 (CXCL7) and (C-C motif) ligand 5 (CCL5), were elevated in the circulation of LB patients in comparison to healthy individuals., (© The Author(s) 2022. Published by Oxford University Press on behalf of the British Society for Immunology.)

Background: The use of anticoagulants has been endorsed by different hematological societies as coagulation abnormalities are key features of COVID-19 patients. This systematic review and meta-analysis aims to provide the most recent update on available evidence on the clinical benefits and risk of oral and parenteral anticoagulants, as well agents with anticoagulant properties, in hospitalized and post-discharge COVID-19 patients., Methods: This systematic review synthesizes data on the outcome of anticoagulation in hospitalized and post-discharge COVID-19 patients. Dichotomous variables from individual studies were pooled by risk ratio (RR) and their 95% confidence interval (95% CI) using the random-effects model. Meta-analyses were performed when feasible., Results: We included 32 studies from 2.815 unique citations, including 7 randomized clinical trials. A total of 33.494 patients were included. Outcomes measured include mortality and survival rates, the requirement for ICU care and mechanical ventilation. A pooled meta-analysis favors anticoagulant compared to no anticoagulant with reduced mortality in hospitalized patients (RR 0,55; 95%CI 0,43-0,66; p<0,001). Higher dose of anticoagulant also showed treatment benefit compared to standard prophylactic dose in selected populations (RR 0,68; 95%CI 0,40-0,96; p<0,001). Regular, pre-hospital anticoagulation prior to hospitalization yielded mixed result. There are currently no data on the benefit of anticoagulation on post-discharge COVID-19 patients., Conclusion: Determination of the presence of thrombosis in COVID-19 is important, as therapeutic dosage of anticoagulants, rather than prophylatic dose, would be indicated in such clinical situation. Anticoagulants were found to decrease the mortality of hospitalized COVID-19. The results from this study are important in the tailored treatment of COVID-19 patients. Further studies on the need for oral anticoagulation for outpatients or post-discharge is warranted. This study has been registered in PROSPERO database (CRD42020201418).

After being declared as a pandemic on March 11, 2020 by the World Health Organization, COVID-19 has affected 497 million people worldwide as of 9 April 2022. COVID-19 is a disease with a plethora of clinical manifestations, which extends to those beyond pulmonary signs and symptoms. Studies that report on the clinical presentation of COVID-19 rarely report specifically on cases with only extrapulmonary manifestations of COVID-19. Extrapulmonary clinical presentations of COVID-19 without pulmonary signs and symptoms is rare, and in such cases, COVID-19 is rarely suspected.We herewith describe four patients with extrapulmonary manifestations of COVID-19, with positive SARS-COV-2 PCR when the test was performed for initial patient screening. The first patient is a 44-year-old female who developed painful ulcer with burning sensation at the lateral side of the tongue along with low grade fever. This symptom appeared after the initial complaints of coughing and nasal congestion subsided.  The second patient is a 37-year-old male, who complained of red eyes  with itchiness and increased tear production for 3 days before seeing an ophthalmologist. The third patient is a 44-year-old female who developed burning sensation and soreness on her throat upon swallowing with fever and chills. These symptoms appear consecutively without any respiratory complaint. The fourth patient is a previously healthy, 30-year-old female, with a normal weight and BMI, and without any comorbidity, cardiovascular risk and neither personal nor family history of cardiovascular disease. In these 4 patients, COVID-19 stomatitis, conjunctivitis, pharyngitis and COVID-19-associated atrial fibrillation was subsequently diagnosed, respectively.In the pandemic stage of COVID-19, COVID-19 screening has often been routinely performed due to the high risk of transmission. However, the decrease in the number of COVID-19 cases may prompt physicians to perform SARS-COV-2 testing based on clinical suspicion. It is imperative to consider the likelihood of COVID-19 and perform SARS-COV-2 PCR in patients with extrapulmonary complaints that have persisting complaints despite treatment.

Background: Thrombocytopenia, bleeding and plasma leakage are major complications of dengue. Activation of endogenous sialidases with desialylation of platelets and endothelial cells may underlie these complications. We aimed to assess the effects of the neuraminidase inhibitor oseltamivir on platelet recovery and plasma leakage in dengue., Methods: We performed a phase 2, double-blind, multicenter, randomized trial in adult dengue patients with thrombocytopenia (<70,000/μl) and a duration of illness ≤ 6 days. Oseltamivir phosphate 75mg BID or placebo were given for a maximum of five days. Primary outcomes were the time to platelet recovery (≥ 100,000/μl) or discharge from hospital and the course of measures of plasma leakage., Results: A total of 70 patients were enrolled; the primary outcome could be assessed in 64 patients (31 oseltamivir; 33 placebo). Time to platelet count ≥100,000/μl (n = 55) or discharge (n = 9) were similar in the oseltamivir and placebo group (3.0 days [95% confidence interval, 2.7 to 3.3] vs. 2.9 days [2.5 to 3.3], P = 0.055). The kinetics of platelet count and parameters of plasma leakage (gall bladder thickness, hematocrit, plasma albumin, syndecan-1) were also similar between the groups., Discussion: In this trial, adjunctive therapy with oseltamivir phosphate had no effect on platelet recovery or plasma leakage parameters., Trial Registration: ISRCTN35227717., Competing Interests: The authors have declared that no competing interests exist.

Background: Endothelial hyper-permeability with plasma leakage and thrombocytopenia are predominant features of severe dengue virus infection. It is well established that heparanase, the endothelial glycocalyx degrading enzyme, plays a major role in various diseases with vascular leakage. It is yet to be elucidated whether heparanase activity plays a major role in dengue-associated plasma leakage. Moreover, the major source of heparanase secretion and activation in dengue remains elusive. Since a relatively high amount of heparanase is stored in platelets, we postulate that heparanase released by activated platelets contributes to the increased plasma heparanase activity during dengue virus infection., Methods: Heparanase activity (plasma and urine), and heparan sulfate and syndecan-1 (plasma levels) were measured in dengue patients with thrombocytopenia in acute phase (n=30), during course of disease (n=10) and in convalescent phase (n=25). Associations with clinical parameters and plasma leakage markers were explored. Platelets from healthy donors were stimulated with dengue non-structural protein-1, DENV2 virus and thrombin to evaluate heparanase release and activity ex vivo ., Results: Heparanase activity was elevated in acute dengue and normalized during convalescence. Similarly, glycocalyx components, such as heparan sulfate and syndecan-1, were increased in acute dengue and restored during convalescence. Increased heparanase activity correlated with the endothelial dysfunction markers heparan sulfate and syndecan-1, as well as clinical markers of plasma leakage such as ascites, hematocrit concentration and gall-bladder wall thickening. Notably, platelet number inversely correlated with heparanase activity. Ex vivo incubation of platelets with thrombin and live DENV2 virus, but not dengue virus-2-derived non-structural protein 1 induced heparanase release from platelets., Conclusion: Taken together, our findings suggest that the increase of heparanase activity in dengue patients is associated with endothelial glycocalyx degradation and plasma leakage. Furthermore, thrombin or DENV2 activated platelets may be considered as a potential source of heparanase., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Buijsers, Garishah, Riswari, van Ast, Pramudo, Tunjungputri, Overheul, van Rij, van der Ven, Alisjahbana, Gasem, de Mast and van der Vlag.)

Introduction: The COVID-19 pandemic has entered a new phase with the roll-out of several vaccines worldwide at an accelerated phase. The occurrence of a more severe presentation of COVID-19 after vaccination may affect policymakers' decision-making and vaccine uptake by the public. Vaccine-associated disease enhancement (VADE) is the modified presentation of infections in individuals after having received a prior vaccination. Currently, little is known about the potential of vaccine-associated disease enhancement (VADE) following COVID-19 immunization. Case Illustration . We herewith report two patients admitted with confirmed COVID-19 pneumonia with a history of CoronaVac vaccination. The first patient with a relatively milder course of the disease had received two doses of CoronaVac, whereas the second patient with a more progressive course of the disease received only one dose before developing symptoms and being admitted to the hospital. Our observations suggest that vaccination could act in boosting the inflammatory process and reveal the previously asymptomatic COVID-19 illness. Theoretically, vaccines could induce VADE, where only suboptimal, nonprotective titers of neutralizing antibodies were produced or proinflammatory T-helper type 2 response was induced. Secondly, enhanced respiratory disease (ERD) could manifest, where pulmonary symptoms are more severe due to peribronchial monocytic and eosinophilic infiltration. Understanding VADE is important for the decision-making by the public, clinicians, and policymakers and is warranted for successful vaccination uptake., Conclusion: We report two cases of patients developing COVID-19 shortly after CoronaVac vaccination in which VADE is likely. We recommend that current vaccination strategies consider the measurement of neutralizing antibody titer as a guide in ensuring the safest strategy for mass immunization. Studies are needed to investigate the true incidence of VADE on vaccinated individuals as well as on how to differentiate between VADE and severe manifestations of COVID-19 that are unrelated to vaccination., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Rahajeng N. Tunjungputri et al.)

COVID-19 is a disease reported to suppress cellular immunity. This may lead to the development of opportunistic infections, among others black fungus, or mucormycosis. On the other hand, pre-existing defect in immunity may render patients susceptible to both mucormycosis and COVID-19. Mucormycosis is a relatively rare fungal infection with rapid progression unless diagnosed promptly and treated adequately, and urgent surgical and medical intervention is lifesaving. The manifestation of mucormycosis largely depends on the presence of exposure to the pathogen and the existing risk factor of the host. As black fungus is locally invasive, the majority of cases will involve tissue damage with local destruction and contiguous spread to nearby structure. We here with present a case of black fungus complicated with COVID-19 in a man with underlying non-Hodgkin's lymphoma.

Acute bacterial skin and skin-structure infections (ABSSSI) is defined in 2013 by the US Food and Drug Administration as a bacterial cellulitis/erysipelas, major skin abscesses, and wound infections. The Infectious Diseases Society of America (IDSA) in 2014 classifies skin and soft-tissue infection (SSTI) as either non-purulent (which includes cellulitis, erysipelas, and necrotizing infection) or purulent (including furuncle, carbuncle, and abscess). Among hospitalized patients with SSTI, healthcare-associated infections account for 73.5% of all cases. Notably, skin and skin-structure infections caused by Pseudomonas aeruginosa, a common hospital pathogen, was reported to cause higher total cost and longer hospital length of stay compared to non-P. aeruginosa cases, despite causing only approximately 5.7% of all healthcare-associated SSTIs. Infection with P. aeruginosa should always be considered in non-healing skin infections in patients with prolonged hospitalization and antibiotic exposure. Tissue culture, preferably taken by surgical debridement, should be promptly performed; and when hospital-infection is suspected, appropriate antibiotics should be started along with removal of all devitalized tissue and to promote skin and soft tissue healing. Expedited discharge should be considered when possible, with adequate antibiotic treatment and follow up for definitive wound treatment.

Thrombocytopenia and platelet dysfunction are commonly observed in patients with dengue virus (DENV) infection and may contribute to complications such as bleeding and plasma leakage. The etiology of dengue-associated thrombocytopenia is multifactorial and includes increased platelet clearance. The binding of the coagulation protein von Willebrand factor (VWF) to the platelet membrane and removal of sialic acid (desialylation) are two well-known mechanisms of platelet clearance, but whether these conditions also contribute to thrombocytopenia in dengue infection is unknown. In two observational cohort studies in Bandung and Jepara, Indonesia, we show that adult patients with dengue not only had higher plasma concentrations of plasma VWF antigen and active VWF, but that circulating platelets had also bound more VWF to their membrane. The amount of platelet-VWF binding correlated well with platelet count. Furthermore, sialic acid levels in dengue patients were significantly reduced as assessed by the binding of Sambucus nigra lectin (SNA) and Maackia amurensis lectin II (MAL-II) to platelets. Sialic acid on the platelet membrane is neuraminidase-labile, but dengue virus has no known neuraminidase activity. Indeed, no detectable activity of neuraminidase was present in plasma of dengue patients and no desialylation was found of plasma transferrin. Platelet sialylation was also not altered by in vitro exposure of platelets to DENV nonstructural protein 1 or cultured DENV. In contrast, induction of binding of VWF to glycoprotein 1b on platelets using the VWF-activating protein ristocetin resulted in the removal of platelet sialic acid by translocation of platelet neuraminidase to the platelet surface. The neuraminidase inhibitor oseltamivir reduced VWF-induced platelet desialylation. Our data demonstrate that excessive binding of VWF to platelets in dengue results in neuraminidase-mediated platelet desialylation and platelet clearance. Oseltamivir might be a novel treatment option for severe thrombocytopenia in dengue infection., Competing Interests: The authors have declared that no competing interests exist.

Background: Severe leptospirosis is frequently complicated by a hemorrhagic diathesis, of which the pathogenesis is still largely unknown. Thrombocytopenia is common, but often not to the degree that spontaneous bleeding is expected. We hypothesized that the hemorrhagic complications are not only related to thrombocytopenia, but also to platelet dysfunction, and that increased binding of von Willebrand factor (VWF) to platelets is involved in both platelet dysfunction and increased platelet clearance., Methodology/principal Findings: A prospective study was carried out in Semarang, Indonesia, enrolling 33 hospitalized patients with probable leptospirosis, of whom 15 developed clinical bleeding, and 25 healthy controls. Platelet activation and reactivity were determined using flow cytometry by measuring the expression of P-selectin and activation of the αIIbβ3 integrin by the binding of fibrinogen in unstimulated samples and after ex vivo stimulation by the platelet agonists adenosine-diphosphate (ADP) and thrombin-receptor activating peptide (TRAP). Platelet-VWF binding, before and after VWF stimulation by ristocetin, as well as plasma levels of VWF, active VWF, the VWF-inactivating enzyme ADAMTS13, thrombin-antithrombin complexes (TAT) and P-selectin were also measured. Bleeding complications were graded using the WHO bleeding scale. Our study revealed that platelet activation, with a secondary platelet dysfunction, is a feature of patients with probable leptospirosis, especially in those with bleeding manifestations. There was a significant inverse correlation of bleeding score with TRAP-stimulated P-selectin and platelet-fibrinogen binding (R = -0.72, P = 0.003 and R = -0.66, P = 0.01, respectively) but not with platelet count. Patients with bleeding also had a significantly higher platelet-VWF binding. Platelet counts were inversely correlated with platelet-VWF binding (R = -0.74; P = 0.0009. There were no correlations between platelet-VWF binding and the degree of platelet dysfunction, suggesting that increased platelet-VWF binding does not directly interfere with the platelet αIIbβ3 signaling pathway in patients with probable leptospirosis., Conclusion/significance: Platelet dysfunction is common in probable leptospirosis patients with manifest bleeding. Increased VWF-platelet binding may contribute to the activation and clearance of platelets.

To improve our understanding about the severity of invasive pneumococcal disease (IPD), we investigated the association between the genotype of Streptococcus pneumoniae and disease outcomes for 349 bacteremic patients. A pneumococcal genome-wide association study (GWAS) demonstrated a strong correlation between 30-day mortality and the presence of the phage-derived gene pblB, encoding a platelet-binding protein whose effects on platelet activation were previously unknown. Platelets are increasingly recognized as key players of the innate immune system, and in sepsis, excessive platelet activation contributes to microvascular obstruction, tissue hypoperfusion, and finally multiorgan failure, leading to mortality. Our in vitro studies revealed that pblB expression was induced by fluoroquinolones but not by the beta-lactam antibiotic penicillin G. Subsequently, we determined pblB induction and platelet activation by incubating whole blood with the wild type or a pblB knockout mutant in the presence or absence of antibiotics commonly administered to our patient cohort. pblB-dependent enhancement of platelet activation, as measured by increased expression of the α-granule protein P-selectin, the binding of fibrinogen to the activated αIIbβ3 receptor, and the formation of platelet-monocyte complex occurred irrespective of antibiotic exposure. In conclusion, the presence of pblB on the pneumococcal chromosome potentially leads to increased mortality in patients with an invasive S. pneumoniae infection, which may be explained by enhanced platelet activation. This study highlights the clinical utility of a bacterial GWAS, followed by functional characterization, to identify bacterial factors involved in disease severity., Importance: The exact mechanisms causing mortality in invasive pneumococcal disease (IPD) patients are not completely understood. We examined 349 patients with IPD and found in a bacterial genome-wide association study (GWAS) that the presence of the phage-derived gene pblB was associated with mortality in the first 30 days after hospitalization. Although pblB has been extensively studied in Streptococcus mitis, its consequence for the interaction between platelets and Streptococcus pneumoniae is largely unknown. Platelets are important in immunity and inflammation, and excessive platelet activation contributes to microvascular obstruction and multiorgan failure, leading to mortality. We therefore developed this study to assess whether the expression of pblB might increase the risk of death for IPD patients through its effect on enhanced platelet activation. This study also shows the value of integrating extensive bacterial genomics and clinical data in predicting and understanding pathogen virulence, which in turn will help to improve prognosis and therapy., (Copyright © 2017 Tunjungputri et al.)

Background: Streptococcus pneumoniae, a Gram-positive bacterium carried in the human nasopharynx, is an important human pathogen causing mild diseases such as otitis media and sinusitis as well as severe diseases including pneumonia, meningitis and sepsis. There is a strong resemblance between the anatomy, immunology and physiology of the pig and human species. Furthermore, there are striking similarities between S. suis pathogenesis in piglets and S. pneumoniae pathogenesis in humans. Therefore, we investigated the use of piglets as a model for pneumococcal colonization and invasive disease., Results: Intravenous inoculation of piglets with an invasive pneumococcal isolate led to bacteraemia during 5 days, showing clear bacterial replication in the first two days. Bacteraemia was frequently associated with fever and septic arthritis. Moreover, intranasal inoculation of piglets with a nasopharyngeal isolate led to colonization for at least six consecutive days., Conclusions: This demonstrates that central aspects of human pneumococcal infections can be modelled in piglets enabling the use of this model for studies on colonization and transmission but also on development of vaccines and host-directed therapies. Moreover this is the first example of an animal model inducing high levels of pneumococcal septic arthritis.