ABSTRACT
Background: Krebs von den Lungen-6 (KL-6) is a mucin glycoprotein mainly produced on the surface of alveolar type 2 epithelial cells. Some case-control studies comparing healty subjects to COVID-19 patients in different stages of severity have documented that serum KL-6 levels predict COVID-19 severity and poor clinical outcomes. However, the relevance of KL-6 in patients with severe and critical COVID-19 have not fully elucidated. Method(s): Retrospective data from consecutive severe to critical COVID-19 patients were collected at UOC Clinical Pnuemologica "Vanvitelli", A.O. dei Colli, Naples, Italy. Study included patients with a positive rhinopharyngeal swab for SARS-COV-2 RNA with severe or critical COVID-19. Result(s): Study population characteristics are reported in Table 1. Among 87 patients 24 had poor outcomes (IOT or death). Median KL-6 value in survivors was significantly lower when compared with patients dead or intubated (530 U/mL versus 1069 U/mL p<0.001). KL-6 was correlated with BMI (r: 0.279, p:0.009), LUS Score (r: 0.429, p<0.001), Chung Score (r: 0.390, p<0.001). KL-6 was associated with risk of death or IOT after adjusting for gender, BMI, Charlson Index, Chung Score, and P/F (OR 1.003 95%IC 1.001-1.004, p <0.001). Serum KL-6 value of 968 has a sensivity of 79.2%, specificity of 87.1%, PPV 70.4%, NPV 91.5%, AUC: O.85 for risk of death or IOT (Figure 1). Conclusion(s): The presented research highlights the relevance of serum KL-6 in severe to critical COVID-19 patients in predicting the risk of death or IOT.
ABSTRACT
The mononuclear phagocyte system (MPS), which includes monocytes/macrophages and dendritic cells (DCs), is notably involved in the modulation of immune-inflammatory processes. While the former act as the first natural barrier against any pathogenic noxa, the latter are the must regulators of adaptive immunity. There is evidence that the MPS is a key player in Coronavirus disease-2019 (COVID-19) pathogenesis. We analyzed by multi-parametric flow cytometry the frequency distribution of peripheral blood monocytes expressing the type I interferon-inducible receptor CD169 and of conventional CD1c+ and CD141+ (namely cDC2 and cDC1) and plasmacytoid CD303+ DCs in 40 patients (M= 30;mean age: 68-yrs) with COVID-19 pneumonia on hospital admission. Thirty age- and sex-matched healthy controls were enrolled for comparison. Our preliminary results show that the median frequency of CD169+ monocytes were significantly higher in patients than in controls (3.89 vs. 1.11;p=0.01). Conversely, all DC subsets were markedly depleted in the former (p<0.0001 in all instances), with no apparent association with disease severity (i.e., inflammation markers and radiological extent of lung abnormalities). Both high frequencies of CD169+ monocytes (> than the median value of 3.89 %) and low frequencies of cDC2 cells (less than the median value of 0.09%) were significantly associated with in-hospital mortality. Our findings suggest that the interplay between the different components of the MPS is dysregulated in acute COVID-19 patients. This may explain, at least in part, the imbalance between innate and adaptive immunity and its impact on disease outcome.
ABSTRACT
Introduction: Covid-19 patients may have unusual arrangements of their blood count, compared to most viral infections. Neutrophilia can be associated with lymphopenia within the first few days. Therefore, an increasing neutrophil to lymphocyte ratio on admission has been considered an indicator of the disease severity Among the qualitative anomalies associated with the quantitative ones, reactive lymphocytes and nucleocytoplasmic morphological changes of the neutrophil granulocytes have been reported.Our study aimed to evaluate whether these leukocyte abnormalities modify the morphology of the instrumental cytograms of the Mindray BC6800plus haematological analyser resulting in diagnostic utility. Method(s): We evaluated the instrumental scattergrams provided by the Mindray BC6800plus analyser in 61patients admitted to the Monaldi and SS Trinita Hospitals (Naples and Borgomanero, Italy) with clinical evidence of SARSCoV- 2 infection confirmed with PCR research of viral RNA, comparing them with 61 healthy subjects. We used the 3D-Cube function - which allows a three-dimensional observation - to evaluate the lymphocyte and neutrophil cluster morphology in the DIFF scattergram. Blood cell morphology was assessed by microscopy. A prolonged microscopic review was performed in case of relevant lymphopenia. Result(s): Covid-19 samples showed evocative anomalies of the lymphocyte clusters in 47 out 61 samples (77%) related to the peripheral blood's morphological findings. Cytographic abnormalities concern the presence of an additional high fluorescence lymphocyte cluster - always well separated from the main one - with numerical consistency ranging between a few units to a few dozen (range 7.0 - 126) (Figure 1). Interestingly, the rotation of the 3D-Cube shows a widening of the high fluorescence cells along the FS axis attributable to the heterogeneity of cellular size (Figure 2). The microscopic review showed activated lymphocytes ranging between plasmacytoid and type III Downey morphologies. Positional indices of the neutrophil clusters showed significant differences from normal. Conclusion(s): Further studies need to associate positional indices with cytographic and microscopic anomalies of the neutrophils. The morphology of the lymphocyte clusters resulting from the 3D projections makes possible an accurate activated lymphocytes quantification, especially in severe lymphopenia thus evocative for Covid-19 infection and helpful for diagnostic and prognostic purposes.
ABSTRACT
Introduction: Some parameters evaluated in the complete count blood examination may have prognostic value in many hematological and infectious diseases Erythroblasts (NRBC) are physiologically present in peripheral blood only in the neonatal period at low concentrations, however they may be present in numerous adult pathologies such as thalassemia syndromes, myeloproliferative diseases and extramedullary hematopoiesis. In these cases their presence has been correlated to the severity of the prognosis.Immature granulocytes (IG) are present from 1% to 5%, they can be related to the development of an infection, to an inflammatory or pathological process or to a severe state of hypoxia. The aim of this study is to investigate the prognostic significance of blood erythroblasts and immature granulocytes in of Sars- CoV-2 infection. Method(s): A total of 314 Covid-19 patients (median age 61 years) including 224 males and 90 females were included in this study. NRBC were identified and counted by Sysmex XN-3000 that measures the nucleic acid content using fluorescence angle in the same channel in which white blood cells are counted. Evaluation of IG was performed with the fluorescence optical method Results: Receiver operating characteristic (ROC) curves where used to determine the optimal cut-off values for IG and NRBC that distinguished between critical (IP) and noncritical patients (NIP). Approximately 14.6% of all Covid-19 patients were NRBC-positive while 28.7% were IGpositive The majority of NRBC-positive and IG-positive patients had relevant values already in the first week of hospitalization. The values were more than tripled in IP then in NIP. Finally, in-hospital mortality of NRBCpositive and IG-positive patients were 7.6% and 10.2% respectively Conclusion(s): NRBCs and GIs can help in the early identification of high-risk Covid-19 patients The screening for NRBCs and GIs and can be useful to distinguish between IP and NIP.
ABSTRACT
The basophil activation test (BAT) is a flow cytometric assay that evaluates the percentage of activation or degranulation of peripheral blood basophils, after “in vitro” exposure to specific allergens. In sensitized patients, the stimulation of peripheral blood basophils with a specific allergen induces or up-regulates the expression of molecules, such as CD63 and CD203c, which represent, markers of degranulation and activation of basophils, respectively. The validity of the BAT requires a negative control (sterile saline) and a positive control (anti-IgE molecules). Several studies have demonstrated the role of the BAT in supporting the diagnosis of drug, food and hymenoptera venom allergy. The BAT has shown a low sensitivity but good specificity in diagnosing allergy to drugs such as NSAIDs, beta-lactam antibiotics, quinolones and muscle relaxants. In food allergy, the sensitivity and specificity of the BAT depends on the food;in the case of peanut allergy the sensitivity reaches 96% while the specificity the 100%. In addition, the BAT is an useful tool to monitor the natural resolution of allergies and the clinical effects induced by either immunotherapy or anti-IgE treatment. Finally, the BAT has been utilized to study the pathogenetic mechanisms underlying several IgE-mediated diseases. For example, in patients affected by severe bronchial asthma, the BAT has demonstrated the ability of Staphylococcus aureus enterotoxins to induce the activation of basophils supporting the role of these enterotoxins as “triggers” of the inflammatory cascade in bronchial asthma. In patients with cystic fibrosis the BAT can be used to dis-criminate allergic bronchopulmonary aspergillosis from Aspergillus colonization. More recently, the BAT has been demonstrated as a potential diagnostic tool to evaluate allergy to the polyethylene glycol (PEG) present in the anti-SARS-CoV-2 BNT162b2 mRNA vaccine.
ABSTRACT
An antigenic method for the quantification of SARS-CoV-2 nucleocapside protein (LUMIPULSE SARS-CoV-2 Ag- Fujirebio) both on naso-pharyngeal swab and on saliva has been evaluated on three groups of subjects: sub-intensive care unit hospitalized patients (n=24), patients discharged from this unit (n=22), controls (n=74). The molecular RT-PCR technique was considered the reference method. The cut-off value of 1.04 pg/mL distinguishes sick (hospitalized) from healthy (controls) with sensibility=0.937 and specificity=0.959;area under the ROC curve (0.978);efficiency=0.90. On saliva the qualitative antigenic result (positive if >cut-off) agrees with the qualitative molecular one (k=0.84). Stratifying by groups, in the hospitalized group (with clear prevalence of positives) there is a concordance of the positives of 97%;in the two groups of patients discharged and controls (with clear prevalence of negatives) there is a concordance on the negatives of 91% and 96%, respectively. The qualitative antigenic result on saliva samples is concordant with the molecular qualitative one on the naso-pharyngeal swab (k=0.76).
ABSTRACT
A coronavirus disease 2019 (COVID-19) surveillance study was performed in March-April 2020 among asymptomatic healthcare workers (HCWs) at a specialist infectious diseases hospital in Naples, Italy. All HCWs underwent two rounds of molecular and serological testing for severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). One hundred and fifteen HCWs were tested; of these, two cases of infection were identified by reverse transcriptase polymerase chain reaction and two HCWs were SARS-CoV-2 immunoglobulin G seropositive. The overall prevalence of current or probable previous infection was 3.4%. The infection rate among HCWs was reasonably low. Most of the infected HCWs had been asymptomatic for the preceding 30 days, which supports the need for periodic screening of HCWs for COVID-19.