Hemolysis and blood gas analysis: it's time for a change!

Modern blood gas analyzers are not able to identify hemolysis, lipemia and icterus; therefore, the aim of this study was to assess the influence of hemolysis on blood gas samples. Blood gas analysis represents an essential part in the diagnosis and treatment of critically ill patients, including those affected by the pandemic coronavirus disease 2019 (COVID-19). Hemolysis, lipemia, and icterus, are causes of clinical misinterpretation of laboratory tests. A total of 1244 blood gas specimens were collected over a one-week period from different clinical wards, including the Emergency Department, and were assessed for serum indices on Cobas C6000 CE (Roche Diagnostics, Mannheim, Germany). The prevalence of hemolysis, lipemia, and icterus were 5%, 12%, and 14%, respectively. Sample storage at room temperature, delivery to central laboratory using pneumatic tube system, as well as small sample size, strongly affected blood gas parameters (p < .01). Hemolysis led to an increase in analytical bias for pH, pO2, and potassium, and a significant decrease for pCO2, HCO3-, sodium, and Ca2+ (p <.01). Currently, hemolysis detection systems are not yet widespread, and a rapid centrifugation of samples after blood gas analysis along with the assessment of serum indices represent the only prompt approach to identify unsuitable results, avoiding pitfalls in clinical decision-making, although it cannot be applied to the Emergency Department routine. Blood gas analyzers manufacturers and suppliers should implement automated built-in serum indices detection systems.

Antibody response after two doses of the SARS-CoV-2 Comirnaty vaccine in a Covid-19 positive and Covid-19 negative Italian healthcare workers cohort.

BACKGROUND: Extensive vaccination against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now universally regarded as one of the most effective strategies for counteracting the current pandemic. The durability of the immune response of available vaccines is not known, therefore the quantitative dynamics of serum anti-S antibodies after Comirnaty vaccine in health care workers (HCW) of Desio Hospital was conducted. METHODS: 51 previously infected and 198 not infected HCW, from Desio, Italy were enrolled in the study. Comirnaty double dose schedule was completed by each subject. Specific anti-S antibodies against the SARS-CoV-2 S protein were measured by ECLIA in sequential blood samples. RESULTS: A significant difference was observed beginning at pre priming dose (T0) of the anti-S antibodies between the two subgroups which persisted throughout the study (4 months). A significant reduction occurred after 4 months post-priming dose (T3). Finally, a subgroup of low and late responders with an increasing trend was found. CONCLUSIONS: Specific anti-S antibodies are significantly decreased 4 months post priming dose of Comirnaty vaccine although prior COVID-19 infection seems to escalate humoral response. Further evaluation concerning antibody persistence beyond this point, and the proportion of neutralizing antibodies with higher affinity towards SARS-CoV-2 is needed, especially in naїve and immunosuppressed subjects.

Baseline characteristics of COVID-19 Italian patients admitted to Desio Hospital, Lombardy: a retrospective study.

The correlation of clinical, radiological and laboratory findings of patients at admission in the Emergency Department (ED) with clinical severity and risk of mortality was investigated. Adult coronavirus disease 2019 (COVID-19) patients hospitalized in March 2020 in Desio Hospital, Lombardy, were retrospectively included in the study, and categorized in terms of disease severity and adverse outcome. Out of the 175 patients enrolled, 79% presented one or more comorbidities, with cardiovascular disease being the most frequent (62%). More than half of the patients showed lymphocytopenia and 20% thrombocytopenia. The patients in the severe group presented higher absolute neutrophil count (ANC), C-reactive protein (CRP), AST, LDH, procalcitonin (PCT) and BUN values compared to the non-severe group (p < .05). Increased odds of mortality associated with older age (OR = 22.43; 95% CI 5.22-96.27), partial pressure of oxygen (PaO2)/fraction of inspired oxygen (FIO2) ratio < 200 (OR = 4.97; 95% CI 1.55-15.84), clinical severity (OR = 21.32; 95% CI 2.27-200.13), creatinine > 106.08 µmol/L (OR = 2.87; 95% CI 1.04-7.92) and creatine kinase > 2.90 µkat/L (OR = 3.80; 95% CI 1.31-10.9) were observed on admission (p < .05). The above findings may contribute to identify early risk factors of poor prognosis, and to select the most appropriate management for patients.

The cholesterol metabolite 27-hydroxycholesterol inhibits SARS-CoV-2 and is markedly decreased in COVID-19 patients.

There is an urgent need to identify antivirals against the coronavirus SARS-CoV-2 in the current COVID-19 pandemic and to contain future similar emergencies early on. Specific side-chain cholesterol oxidation products of the oxysterols family have been shown to inhibit a large variety of both enveloped and non-enveloped human viral pathogens. Here we report on the in vitro inhibitory activity of the redox active oxysterol 27-hydroxycholesterol against SARS-CoV-2 and against one of the common cold agents HCoV-OC43 human coronavirus without significant cytotoxicity. Interestingly, physiological serum levels of 27-hydroxycholesterol in SARS-CoV-2 positive subjects were significantly decreased compared to the matched control group, reaching a marked 50% reduction in severe COVID-19 cases. Moreover, no correlation at all was observed between 24-hydroxycholesterol and 25-hydroxycholesterol serum levels and the severity of the disease. Opposite to that of 27-hydroxycholesterol was the behaviour of two recognized markers of redox imbalance, i.e. 7-ketocholesterol and 7ß-hydroxycholesterol, whose serum levels were significantly increased especially in severe COVID-19. The exogenous administration of 27-hydroxycholesterol may represent in the near future a valid antiviral strategy in the worsening of diseases caused by present and emerging coronaviruses.

Performance evaluation of a new and improved cuvette-based automated urinalysis analyzer with phase contrast microscopy.

BACKGROUND: The use of phase contrast in urinalysis has been highly recommended. A new system, sediMAX conTRUST PRO, is now available providing simultaneous automated phase contrast and bright field microscopy. This study aimed to evaluate both analytical and diagnostic performance of this new analyzer. METHODS: Results from 504 samples evaluated with the sediMAX conTRUST PRO were compared to those obtained from the same samples by manual microscopy (MM). Analytical and diagnostic performance were assessed according to established guidelines. RESULTS: The concentration of red blood cells (RBCs)and white blood cells (WBCs) at which the LoQ satisfied a CV< 25% was 12 particles per µL (p/µL) and 8 p/µL, respectively. Within one grade of agreement concordance was quite high, 97.8% for RBCs and 98.0% for WBCs, and above 90% for all other particles. Overall, diagnostic sensitivity and specificity were good (>80%) for the particles considered, although lower sensitivities, 70.6% and 61.8%, were respectively found for hyaline and pathological casts. CONCLUSIONS: The sediMAX conTRUST PRO provides very good performance in terms of RBC and WBC recognition and enumeration, and quite good performance for all other particles. Hyaline cast and pathological cast identification is fine and comparable to other automated systems, but could use further improvement.