Elevated Calprotectin and Abnormal Myeloid Cell Subsets Discriminate Severe from Mild COVID-19.

Blood myeloid cells are known to be dysregulated in coronavirus disease 2019 (COVID-19), caused by SARS-CoV-2. It is unknown whether the innate myeloid response differs with disease severity and whether markers of innate immunity discriminate high-risk patients. Thus, we performed high-dimensional flow cytometry and single-cell RNA sequencing of COVID-19 patient peripheral blood cells and detected disappearance of non-classical CD14LowCD16High monocytes, accumulation of HLA-DRLow classical monocytes (Human Leukocyte Antigen - DR isotype), and release of massive amounts of calprotectin (S100A8/S100A9) in severe cases. Immature CD10LowCD101-CXCR4+/- neutrophils with an immunosuppressive profile accumulated in the blood and lungs, suggesting emergency myelopoiesis. Finally, we show that calprotectin plasma level and a routine flow cytometry assay detecting decreased frequencies of non-classical monocytes could discriminate patients who develop a severe form of COVID-19, suggesting a predictive value that deserves prospective evaluation.

Convalescent plasma therapy for B-cell-depleted patients with protracted COVID-19.

Anti-CD20 monoclonal antibodies are widely used for the treatment of hematological malignancies or autoimmune disease but may be responsible for a secondary humoral deficiency. In the context of COVID-19 infection, this may prevent the elicitation of a specific SARS-CoV-2 antibody response. We report a series of 17 consecutive patients with profound B-cell lymphopenia and prolonged COVID-19 symptoms, negative immunoglobulin G (IgG)-IgM SARS-CoV-2 serology, and positive RNAemia measured by digital polymerase chain reaction who were treated with 4 units of COVID-19 convalescent plasma. Within 48 hours of transfusion, all but 1 patient experienced an improvement of clinical symptoms. The inflammatory syndrome abated within a week. Only 1 patient who needed mechanical ventilation for severe COVID-19 disease died of bacterial pneumonia. SARS-CoV-2 RNAemia decreased to below the sensitivity threshold in all 9 evaluated patients. In 3 patients, virus-specific T-cell responses were analyzed using T-cell enzyme-linked immunospot assay before convalescent plasma transfusion. All showed a maintained SARS-CoV-2 T-cell response and poor cross-response to other coronaviruses. No adverse event was reported. Convalescent plasma with anti-SARS-CoV-2 antibodies appears to be a very promising approach in the context of protracted COVID-19 symptoms in patients unable to mount a specific humoral response to SARS-CoV-2.

Triaging acute pulmonary embolism for home treatment by Hestia or simplified PESI criteria: the HOME-PE randomized trial.

AIMS: The aim of this study is to compare the Hestia rule vs. the simplified Pulmonary Embolism Severity Index (sPESI) for triaging patients with acute pulmonary embolism (PE) for home treatment. METHODS AND RESULTS: Normotensive patients with PE of 26 hospitals from France, Belgium, the Netherlands, and Switzerland were randomized to either triaging with Hestia or sPESI. They were designated for home treatment if the triaging tool was negative and if the physician-in-charge, taking into account the patient's opinion, did not consider that hospitalization was required. The main outcomes were the 30-day composite of recurrent venous thrombo-embolism, major bleeding or all-cause death (non-inferiority analysis with 2.5% absolute risk difference as margin), and the rate of patients discharged home within 24 h after randomization (NCT02811237). From January 2017 through July 2019, 1975 patients were included. In the per-protocol population, the primary outcome occurred in 3.82% (34/891) in the Hestia arm and 3.57% (32/896) in the sPESI arm (P = 0.004 for non-inferiority). In the intention-to-treat population, 38.4% of the Hestia patients (378/984) were treated at home vs. 36.6% (361/986) of the sPESI patients (P = 0.41 for superiority), with a 30-day composite outcome rate of 1.33% (5/375) and 1.11% (4/359), respectively. No recurrent or fatal PE occurred in either home treatment arm. CONCLUSIONS: For triaging PE patients, the strategy based on the Hestia rule and the strategy based on sPESI had similar safety and effectiveness. With either tool complemented by the overruling of the physician-in-charge, more than a third of patients were treated at home with a low incidence of complications.

Circulating Von Willebrand factor and high molecular weight multimers as markers of endothelial injury predict COVID-19 in-hospital mortality.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a respiratory disease associated with endotheliitis and microthrombosis. OBJECTIVES: To correlate endothelial dysfunction to in-hospital mortality in a bi-centric cohort of COVID-19 adult patients. METHODS: Consecutive ambulatory and hospitalized patients with laboratory-confirmed COVID-19 were enrolled. A panel of endothelial biomarkers and von Willebrand factor (VWF) multimers were measured in each patient ≤ 48 h following admission. RESULTS: Study enrolled 208 COVID-19 patients of whom 23 were mild outpatients and 189 patients hospitalized after admission. Most of endothelial biomarkers tested were found increased in the 89 critical patients transferred to intensive care unit. However, only von Willebrand factor antigen (VWF:Ag) scaled according to clinical severity, with levels significantly higher in critical patients (median 507%, IQR 428-596) compared to non-critical patients (288%, 230-350, p < 0.0001) or COVID-19 outpatients (144%, 133-198, p = 0.007). Moreover, VWF high molecular weight multimers (HMWM) were significantly higher in critical patients (median ratio 1.18, IQR 0.86-1.09) compared to non-critical patients (0.96, 1.04-1.39, p < 0.001). Among all endothelial biomarkers measured, ROC curve analysis identified a VWF:Ag cut-off of 423% as the best predictor for in-hospital mortality. The accuracy of VWF:Ag was further confirmed in a Kaplan-Meier estimator analysis and a Cox proportional Hazard model adjusted on age, BMI, C-reactive protein and D-dimer levels. CONCLUSION: VWF:Ag is a relevant predictive factor for in-hospital mortality in COVID-19 patients. More than a biomarker, we hypothesize that VWF, including excess of HMWM forms, drives microthrombosis in COVID-19.

White blood count, D-dimers, and ferritin levels as predictive factors of pulmonary embolism suspected upon admission in noncritically ill COVID-19 patients: The French multicenter CLOTVID retrospective study.

BACKGROUND: A high prevalence of pulmonary embolism (PE) has been described during COVID-19. Our aim was to identify predictive factors of PE in non-ICU hospitalized COVID-19 patients. METHODS: Data and outcomes were collected upon admission during a French multicenter retrospective study, including patients hospitalized for COVID-19, with a CT pulmonary angiography (CTPA) performed in the emergency department for suspected PE. Predictive factors significantly associated with PE were identified through a multivariate regression model. RESULTS: A total of 88 patients (median [IQR] age of 68 years [60-78]) were analyzed. Based on CTPA, 47 (53.4%) patients were diagnosed with PE, and 41 were not. D-dimer ≥3000 ng/mL (OR 8.2 [95% CI] 1.3-74.2, sensitivity (Se) 0.84, specificity (Sp) 0.78, P = .03), white blood count (WBC) ≥12.0 G/L (29.5 [2.3-1221.2], Se 0.47, Sp 0.92, P = .02), and ferritin ≥480 µg/L (17.0 [1.7-553.3], Se 0.96, Sp 0.44, P = .03) were independently associated with the PE diagnosis. The presence of the double criterion D-dimer ≥3000 ng/mL and WBC ≥12.0 G/L was greatly associated with PE (OR 21.4 [4.0-397.9], P = .004). CONCLUSION: The white blood count, the D-dimer and ferritin levels could be used as an indication for CTPA to confirm PE on admission in non-ICU COVID-19 patients.

Oxidative Stress and Inflammatory Biomarkers for the Prediction of Severity and ICU Admission in Unselected Patients Hospitalized with COVID-19.

OBJECTIVE: We aimed to investigate the prognostic performances of oxidative stress (OS), inflammatory and cell activation biomarkers measured at admission in COVID-19 patients. DESIGN: retrospective monocentric study. SETTING: patients with suspected SARS-CoV-2 infection (COVID-19) admitted to the hospital. PATIENTS: One hundred and sixty documented and unselected COVID-19-patients. Disease severity (from mild to critical) was scored according to NIH's classification. INTERVENTIONS: none. MEASUREMENTS AND MAIN RESULTS: We measured OS biomarkers (thiol, advanced oxidation protein products (AOPP), ischemia-modified albumin (IMA)), inflammation biomarkers (interleukin-6 (IL-6), presepsin) and cellular activation biomarkers (calprotectin) in plasma at admission. Thiol concentrations decreased while IMA, IL-6, calprotectin and PSEP increased with disease severity in COVID-19 patients and were associated with increased O2 needs and ICU admission. The best area under the receiver-operating-characteristics curve (AUC) for the prediction of ICU admission was for thiol (AUC = 0.762). A thiol concentration <154 µmol/L was predictive for ICU admission (79.7% sensitivity, 64.6% specificity, 58.8% positive predictive value, 78.9% negative predictive value). In a stepwise logistic regression, we found that being overweight, having dyspnoea, and thiol and IL-6 plasmatic concentrations were independently associated with ICU admission. In contrast, calprotectin was the best biomarker to predict mortality (AUC = 0.792), with an optimal threshold at 24.1 mg/L (94.1% sensitivity, 64.9% specificity, 97.1% positive predictive value and 98.9% negative predictive value), and survival curves indicated that high IL-6 and calprotectin concentrations were associated with a significantly increased risk of mortality. CONCLUSIONS: Thiol measurement at admission is a promising tool to predict ICU admission in COVID-19-patients, whereas IL-6 and calprotectin measurements effectively predict mortality.

A colonic mass revealing a disseminated crystal storing histiocytosis secondary to indolent multiple myeloma: a case report with literature review.

BACKGROUND: Crystal storing histiocytosis is a rare disorder associated with monoclonal gammopathy. In this disease, monoclonal heavy and light chains accumulate in the lysosome of macrophages, leading to histiocytic reaction in different organs. It is secondary to the presence of a small B-cell clone, responsible for monoclonal immunoglobulin production. Histological diagnosis is a challenge and differential diagnoses include fibroblastic and histiocytic neoplasm. Clinical manifestations depend on the involved organs, rarely including peritoneum or digestive tract. CASE PRESENTATION: We present a case of a 75-year-old with a medical history of colonic carcinoma. She presented with abdominal pain and inflammatory syndrome revealing a colonic mass. Hemicolectomy was performed. Initial diagnosis was fibroblastic tumour. The patient worsened, and diagnosis of a diffuse crystal storing histiocytosis was finally done. Haematological exploration found an indolent IgG-kappa multiple myeloma. The initial treatment with conventional chemotherapy did not permit an improvement of the patient condition. Immunotherapy with anti-CD38 monoclonal antibody (daratumumab) was proposed with a clinical and biological response. CONCLUSION: This case report emphasizes the histopathological challenge of histiocytic tumours which may involve digestive track. It focuses on the concept of monoclonal gammopathy of clinical significance, which can have a large spectrum of manifestations.

Acute paraplegia due to schistosomiasis: an uncommon cause in developed countries.

We present a case of a young African migrant from Guinea-Conakry presented to a French emergency department with burning pain in both feet for 2 days. The symptoms progressed to limb paraparesis with sphincter disorders. A magnetic resonance imaging (MRI) scan showed a hyperintense spinal cord lesion without contrast enhancement extending from the T6 vertebrae to the conus medullaris. Cerebrospinal fluid exam (CFE) showed an isolated hyperproteinorachia (0.61 g/l). Schistosomiasiss serology was positive and a rectal biopsy showed a schistosoma egg surrounded by an inflammatory reaction with granulomatosis. After steroid and antihelminthic therapy, accompanied by intensive physical therapy, the patient had an improved neurological neurological outcome.