Leukocyte cell population data as potential markers of COVID-19 disease characterization.

Background: The usefulness of leukocyte cell population data (CPD) is currently being investigated. In COVID-19 pandemic several reports showed the clinical importance of hematological parameters. Our study aimed to assess CPDs in Sars CoV-2 patients as new disease markers. Methods: From February to April 2020 (1st wave) 540 and from September to December 2020 (2nd wave) 2821 patients respectively were enrolled. SARS CoV-2 infection diagnosis was carried out by Multiplex rRT-PCR from nasopharyngeal swabs. CPDs were detected by XN 2000 hematology analyzer (Sysmex Corporation). A comparison between two disease waves was performed. Additionally, C-reactive protein (CRP) and lactate dehydrogenase (LDH) were assayed. Results: CPDs were classified into: cell complextity, DNA/RNA content and abnormal sized cells. We detected parameters increased from the reference population for all cell types for both 1st and 2nd wave (p<0.05). However, in the 2nd vs 1st wave 5 CPDs vs 9 CPDs were found. In addition we observed higher CPD values of the 1st compared to 2nd wave: (NE-SFL) (p<0.001), (LY-Y) (p<0.0001), (LY-Z) (p<0.0001), (MO-X) (p<0.0001), (MO-Y) (p<0.0001). These findings were confirmed by the higher concentrations of CRP and LDH in the 1st vs 2nd wave: 17.3 mg/L (8.5-59.3) vs 6.3 mg/L (2.3-17.6) (p<0.001) and 241.5 IU/L (201-345) vs 195 IU/L (174-228) (p< 0.001) (median, interquartile range) respectively. Conclusions: CPDs showed increased cell activation in 1st wave patients confirmed by clinical and biochemical data, associated with worse clinical conditions. Results highlighted the CPDs as disease characterization markers or useful for a risk model.

High immature platelet fraction with reduced platelet count on hospital admission. Can it be useful for COVID-19 diagnosis?

INTRODUCTION: Health professions are heavily engaged facing the current threat of SARS-CoV-2 (COVID-19). Although there are many diagnostic tools, an accurate and rapid laboratory procedure for diagnosing COVID-19 is recommended. We focused on platelet parameters as the additional biomarkers for clinical diagnosis in patients presenting to the emergency department (ED). MATERIALS AND METHODS: Five hundred and sixty-one patients from February to April 2020 have been recruited. Patients were divided into three groups: (N = 50) COVID-19 positive and (N = 21) COVID-19 negative with molecular testing, (N = 490) as reference population without molecular testing. A Multiplex rRT-PCR from samples collected by nasopharyngeal swabs was performed and the hematological data collected. RESULTS: We detected a mild anemia in COVID-19 group and lymphopenia against reference population: hemoglobin (g/dL) 13.0 (11.5-14.8) versus 13.9 (12.8-15.0) (P = .0135); lymphocytes (109 /L) 1.24 (0.94-1.73) versus 1.99 (1.49-2.64) (P < .0001). In addition, abnormal platelet parameters as follows (COVID group vs reference population): PLT (×109 /L) 209 (160-258) vs 236 (193-279) (P = .0239). IPF (%) 4.05 (2.5-5.9) versus 3.4 (2.2-4.9) (P = .0576); H-IPF (%) 1.25 (0.8-2.2) versus 0.95 (0.6-1.5) (P = .0171) were identified. In particular, COVID positive group had a high H-IPF/IPF Ratio compared to reference population [0.32 (0.29-0.36) versus 0.29 (0.26-0.32), respectively, (P = .0003)]. Finally, a PLT difference of nearly 50 × 109 /L between pre/postCOVID-19 sampling for each patient was found (N = 42) (P = .0194). CONCLUSIONS: COVID-19 group results highlighted higher IPF and H-IPF values, with increased H-IPF/IPF Ratio, associated to PLT count reduction. These findings shall be adopted for a timely diagnosis of patients upon hospital admission.

Alveolar membrane conductance decreases as BNP increases during exercise in heart failure. Rationale for BNP in the evaluation of dyspnea.

BACKGROUND: In left ventricular failure (LVF) patients, brain natriuretic peptide (BNP), lung diffusion for carbon monoxide (DLCO), and alveolar-membrane conductance (DM) correlate with LVF severity and prognosis. The reduction of DLCO and DM during exercise reflects pulmonary edema formation. METHODS AND RESULTS: To evaluate, in LVF patients, the correlation between BNP and lung diffusion parameters at rest and during exercise, we studied 17 severe LVF patients, 13 moderate, and 10 normals measuring BNP and lung diffusion parameters before, at the end, and 1 hour after a 10-minute high-intensity constant-workload exercise. At rest, a significant correlation exists between BNP and lung diffusion parameters. Resting BNP, DLCO, and DM correlate with peak oxygen consumption (P < .0001 for all analyses). With exercise, BNP increase is significant (severe LVF 180 +/- 49 pg/mL, moderate 68 +/- 58, normals 18 +/- 12); differently, only in severe LVF, with exercise, DLCO (-1.1 +/- 0.7 mL/mm Hg/min, P < .0001) and DM (-6.4 +/- 2.8, P < .0006) decrease. One hour after exercise, only in severe LVF, BNP is still higher than at rest, while DLCO, DM, and DM/Vc are lower. Significant correlations are observed between BNP and DM changes during exercise and recovery (P < .0001) in severe LVF. CONCLUSIONS: In severe LVF, BNP changes during exercise correlate with simultaneous reductions in DM, suggesting that BNP increase and pulmonary edema formation could be related.

Nephrocheck after cardiac surgery: Does it play a role in daily practice? A sequel of "Nephrocheck results should be corrected for dilution".

Acute kidney injury is a well-recognized complication after cardiac surgery and significantly affects morbidity and mortality. Although the mechanisms of acute kidney injury are not fully understood, Nephrocheck (Astute Medical, San Diego, CA, USA) is a meter for early detection of acute kidney injury based on bedside urinalysis of two cell-cycle arrest biomarkers. However, considerable overlap in the AKIRiskTM score of different RIFLE groups makes interpretation of the score uncertain. A possible reason for the overlap in the AKIRisk score between different RIFLE groups could be that the score is not corrected for dilution. We performed a pilot study to explore the applicability of the test in our daily practice. A total of 68 patients electively scheduled for cardiac surgery with at least two of the following inclusion criteria: age > 70 years, glomerular filtration rate <60 mL/min, left ventricular ejection fraction <41%, redo procedure and combined procedures have been enrolled in the study, and 25 of them developed acute kidney injury. We described the correlation between urine creatinine and Nephrocheck, all the samples with low Nephrocheck (<0.2) also have low urine creatinine, less than 50 mg/dL, detecting a potential diluted sample. In conclusion, in our daily practice AKIRisk score, together with an assessment of whether urine is diluted or concentrated can better discriminate between various degrees of acute kidney injury.

Improvement of neutrophil gelatinase-associated lipocalin sensitivity and specificity by two plasma measurements in predicting acute kidney injury after cardiac surgery.

INTRODUCTION: Acute kidney injury (AKI) remains among the most severe complication after cardiac surgery. The aim of this study was to evaluate the neutrophil gelatinase-associated lipocalin (NGAL) as possible biomarker for the prediction of AKI in an adult cardiac population. MATERIALS AND METHODS: Sixty-nine consecutive patients who underwent cardiac surgeries in our hospital were prospectively evaluated. In the intensive care unit (ICU) NGAL was measured as a new biomarker of AKI besides serum creatinine (sCrea). Patients with at least two factors of AKI risk were selected and samples collected before the intervention and soon after the patient's arrival in ICU. As reference standard, sCrea measurements and urine outputs were evaluated to define the clinical AKI. A Triage Meter for plasma NGAL fluorescence immunoassay was used. RESULTS: Acute kidney injury occurred in 24 of the 69 patients (35%). Analysis of post-operative NGAL values demonstrated an AUC of 0.71, 95% CI (0.60 - 0.82) with a cut-off = 154 ng/mL (sensitivity = 76%, specificity = 59%). Moreover, NGAL after surgery had a good correlation with the AKI stage severity (P ≤ 0.001). Better diagnostic results were obtained with two consecutive tests: sensitivity 86% with a negative predictive value (NPV) of 87%. At 10-18 h after surgery sCrea measurement, as confirmatory test, allowed to reach a more sensitivity and specificity with a NPV of 96%. CONCLUSIONS: The assay results showed an improvement of NGAL diagnostic accuracy evaluating two tests. Consequently, NGAL may be useful for a timely treatment or for the AKI rule out in ICU patients.

Significance of consecutive international normalized ratio (INR) outcomes using statistical control rules in long-term anticoagulated patients. Optimization of laboratory monitoring and interpretation of borderline measurements.

Analysis of serial measurements is needed to elaborate observations in all fields of medical research. In the present study, retrospective data of anticoagulated patients were used to calculate a mean of observations and control limits, X+/-1sigma and X+/-2sigma (mean+/-standard deviation). During 18 months of coagulation monitoring, 45 patients without major oral anticoagulant therapy complications, with more international normalized ratio (INR) determinations in the therapeutic range and with a normal distribution of INR values according to the Kurtosis coefficient, were selected. The cumulative distribution functions allowed us to obtain critical limits of INR with a cumulative probability (p). Control limits, calculated for a therapeutic control chart, indicated through different control rules, 1S2 or 2S1, an alarm signal to analyze the cause of INR outside the therapeutic range. Our investigation suggested that for results at the level of the therapeutic control limits, we needed at least two consecutive INR results to detect a significant over- or under-anticoagulation. The therapeutic control chart method should be a useful means in clinical practice for evaluating the statistical significance of consecutive and borderline INR outcomes. Analytical improvements and control rules applied to laboratory monitoring may help optimize drug dose administration.