Digestive Biomarkers of Laryngopharyngeal Reflux: A Preliminary Prospective Controlled Study.

OBJECTIVE: To investigate the digestive enzymes and biomarkers in the saliva of patients with laryngopharyngeal reflux (LPR) and asymptomatic individuals. STUDY DESIGN: Prospective controlled study. SETTING: Multicenter study. METHODS: Patients with LPR at the hypopharyngeal-esophageal impedance-pH monitoring (HEMII-pH) and asymptomatic individuals were consecutively recruited from January 2020 to April 2023 from 2 University Hospitals. The saliva of patients (off PPIs) and asymptomatic individuals was collected to measure pH, elastase, bile salts, cholesterol, gastric, and pancreatic lipases. Anxiety, symptoms, and findings were studied through perceived stress scale (PSS), reflux symptom score (RSS), and reflux sign assessment (RSA). RESULTS: Sixty-seven LPR patients and 57 asymptomatic individuals completed the evaluations. LPR patients reported higher PSS, RSS, and RSA than asymptomatic individuals. The mean saliva pH was more alkaline in LPR patients (7.23: 95% confidence interval [CI]: 7.08, 7.38) compared to controls (6.13; 95% CI: 5.95, 6.31; P = .001). The mean concentration of elastase was higher in patients (51.65 µg/mL; 95% CI: 44.47, 58.83 µg/mL) versus asymptomatic individuals (25.18 µg/mL; 95% CI: 21.64, 28.72 µg/mL; P = .001). The saliva cholesterol reported higher concentration in healthy individuals (3.43 mg/dL; 95% CI: 3.21, 3.65 mg/dL) compared to patients (1.16 mg/dL; 95% CI: 1.05, 1.27 mg/dL; P = .001). The saliva pH, and elastase concentration were significantly associated with the baseline RSS, while saliva cholesterol was negatively associated with the severity of RSS and RSA. CONCLUSION: Cholesterol, bile salts, and elastase are biomarkers of LPR and should be considered to develop future non-invasive saliva device for the detection of LPR.

Chemerin plasma levels are increased in COVID-19 patients and are an independent risk factor of mortality.

Background: Chemerin is an extracellular protein with chemotactic activities and its expression is increased in various diseases such as metabolic syndrome and inflammatory conditions. Its role in lung pathology has not yet been extensively studied but both known pro- and anti-inflammatory properties have been observed. The aim of our study was to evaluate the involvement of the chemerin/ChemR23 system in the physiopathology of COVID-19 with a particular focus on its prognostic value. Methods: Blood samples from confirmed COVID-19 patients were collected at day 1, 5 and 14 from admission to Erasme Hospital (Brussels - Belgium). Chemerin concentrations and inflammatory biomarkers were analyzed in the plasma. Blood cells subtypes and their expression of ChemR23 were determined by flow cytometry. The expression of chemerin and ChemR23 was evaluated on lung tissue from autopsied COVID-19 patients by immunohistochemistry (IHC). Results: 21 healthy controls (HC) and 88 COVID-19 patients, including 40 in intensive care unit (ICU) were included. Plasma chemerin concentration were significantly higher in ICU patients than in HC at all time-points analyzed (p<0.0001). Moreover, they were higher in deceased patients compared to survivors (p<0.05). Logistic univariate regression and multivariate analysis demonstrated that chemerin level at day 14 of admission was an independent risk factor for death. Accordingly, chemerin levels correlated with inflammatory biomarkers such as C-reactive protein and tumor necrosis factor α. Finally, IHC analysis revealed a strong expression of ChemR23 on smooth muscle cells and chemerin on myofibroblasts in advanced acute respiratory distress syndrome (ARDS). Discussion: Increased plasma chemerin levels are a marker of severity and may predict death of COVID-19 patients. However, multicentric studies are needed, before chemerin can be considered as a biomarker of severity and death used in daily clinical practice. Further studies are also necessary to identify the precise mechanisms of the chemerin/ChemR23 system in ARDS secondary to viral pneumonia.

Development and validation of a simple correction method for the measurement of neuron-specific enolase in hemolyzed serum samples.

The Neuron-specific enolase (NSE), a biomarker of neuroendocrine tumors or ischemic brain damage, has limited clinical applicability since its measurement is overestimated by hemolysis. In this study, an NSE correction method was developed for hemolyzed samples. The NSE concentration and the hemolysis index (HI) of serum were measured before and after spiking a hemolysate prepared with red blood cells from the serum-separating tube and extrapolating the NSE value corresponding to a HI of zero. To validate the approach (n = 46), NSE concentrations and HI were measured before (NSE0 and HI0) and after spiking the samples with 50 µL (HIA, NSEA) and 100 µL (HIB, NSEB) of hemolysate. A linear regression analysis was performed between (HIA, NSEA) and (HIB, NSEB). The y-intercept was taken as the corrected NSE concentration (NSEintercept) and compared with NSE0. On the same samples, the equation of Tolan et al. was applied and the corrected values of NSE (NSEcorr) were compared to NSE0. The average bias (±SD) between the NSE0 and the NSEintercept was equal to -3.2% (± 14.3) versus 34.6% (± 19.8) against the NSEcorr. Applying the allowable total error proposed by the European Federation of Laboratory Medicine, 72% of the NSE results were adequately corrected while the reference method corrected only 8.7% of the results. The individualized hemolysis correction method developed is simple, fast, requires one serum-separating tube, provides increased accuracy compared to the method described by Tolan et al. and should improve the quality of patient care.

Clinical Assessment of Breast Volume: Can 3D Imaging Be the Gold Standard?

Three-dimensional (3D) camera systems are increasingly used for computerized volume calculations. In this study we investigate whether the Vectra XT 3D imaging system is a reliable tool for determination of breast volume in clinical practice. It is compared with the current gold standard in literature, magnetic resonance imaging (MRI), and current clinical practice (plastic surgeon's clinical estimation). METHODS: Breast volumes of 29 patients (53 breasts) were evaluated. 3D images were acquired by Vectra XT 3D imaging system. Pre-existing breast MRI images were collected. Both imaging techniques were used for volume analyses, calculated by two independent investigators. Breast volume estimations were done by plastic surgeons during outpatient consultations. All volume measurements were compared using paired samples t-test, intra-class correlation coefficient, Pearson's correlation, and Bland-Altman analysis. RESULTS: Two 3D breast volume measurements showed an excellent reliability (intra-class correlation coefficient: 0.991), which was comparable to the reliability of MRI measurements (intra-class correlation coefficient: 0.990). Mean (SD) breast volume measured with 3D breast volume was 454 cm3 (157) and with MRI was 687 cm3 (312). These volumes were significantly different, but a linear association could be found: y(MRI) = 1.58 × (3D) - 40. Three-dimensional breast volume was not significantly different from volume estimation made by plastic surgeons (472 cm3 (69), P = 0.323). CONCLUSIONS: The 3D imaging system measures lower volumes for breasts than MRI. However, 3D measurements show a linear association with MRI and have excellent reliability, making them an objective and reproducible measuring method suitable for clinical practice.