Illuminating the Tiny World: A Navigation Guide for Proper Raman Studies on Microorganisms.

Raman spectroscopy is an emerging method for the identification of bacteria. Nevertheless, a lot of different parameters need to be considered to establish a reliable database capable of identifying real-world samples such as medical or environmental probes. In this review, the establishment of such reliable databases with the proper design in microbiological Raman studies is demonstrated, shining a light into all the parts that require attention. Aspects such as the strain selection, sample preparation and isolation requirements, the phenotypic influence, measurement strategies, as well as the statistical approaches for discrimination of bacteria, are presented. Furthermore, the influence of these aspects on spectra quality, result accuracy, and read-out are discussed. The aim of this review is to serve as a guide for the design of microbiological Raman studies that can support the establishment of this method in different fields.

Use of polymers as wavenumber calibration standards in deep-UVRR.

Deep-UV resonance Raman spectroscopy (UVRR) allows the classification of bacterial species with high accuracy and is a promising tool to be developed for clinical application. For this attempt, the optimization of the wavenumber calibration is required to correct the overtime changes of the Raman setup. In the present study, different polymers were investigated as potential calibration agents. The ones with many sharp bands within the spectral range 400-1900 cm-1 were selected and used for wavenumber calibration of bacterial spectra. Classification models were built using a training cross-validation dataset that was then evaluated with an independent test dataset obtained after 4 months. Without calibration, the training cross-validation dataset provided an accuracy for differentiation above 99 % that dropped to 51.2 % after test evaluation. Applying the test evaluation with PET and Teflon calibration allowed correct assignment of all spectra of Gram-positive isolates. Calibration with PS and PEI leads to misclassifications that could be overcome with majority voting. Concerning the very closely related and similar in genome and cell biochemistry Enterobacteriaceae species, all spectra of the training cross-validation dataset were correctly classified but were misclassified in test evaluation. These results show the importance of selecting the most suitable calibration agent in the classification of bacterial species and help in the optimization of the deep-UVRR technique.

Comparison of Different Label-Free Raman Spectroscopy Approaches for the Discrimination of Clinical MRSA and MSSA Isolates.

Methicillin-resistant Staphylococcus aureus (MRSA) is classified as one of the priority pathogens that threaten human health. Resistance detection with conventional microbiological methods takes several days, forcing physicians to administer empirical antimicrobial treatment that is not always appropriate. A need exists for a rapid, accurate, and cost-effective method that allows targeted antimicrobial therapy in limited time. In this pilot study, we investigate the efficacy of three different label-free Raman spectroscopic approaches to differentiate methicillin-resistant and -susceptible clinical isolates of S. aureus (MSSA). Single-cell analysis using 532 nm excitation was shown to be the most suitable approach since it captures information on the overall biochemical composition of the bacteria, predicting 87.5% of the strains correctly. UV resonance Raman microspectroscopy provided a balanced accuracy of 62.5% and was not sensitive enough in discriminating MRSA from MSSA. Excitation of 785 nm directly on the petri dish provided a balanced accuracy of 87.5%. However, the difference between the strains was derived from the dominant staphyloxanthin bands in the MRSA, a cell component not associated with the presence of methicillin resistance. This is the first step toward the development of label-free Raman spectroscopy for the discrimination of MRSA and MSSA using single-cell analysis with 532 nm excitation. IMPORTANCE Label-free Raman spectra capture the high chemical complexity of bacterial cells. Many different Raman approaches have been developed using different excitation wavelength and cell analysis methods. This study highlights the major importance of selecting the most suitable Raman approach, capable of providing spectral features that can be associated with the cell mechanism under investigation. It is shown that the approach of choice for differentiating MRSA from MSSA should be single-cell analysis with 532 nm excitation since it captures the difference in the overall biochemical composition. These results should be taken into consideration in future studies aiming for the development of label-free Raman spectroscopy as a clinical analytical tool for antimicrobial resistance determination.

Label-free differentiation of clinical E. coli and Klebsiella isolates with Raman spectroscopy.

Raman spectroscopy is a promising spectroscopic technique for microbiological diagnostics. In routine diagnostic, the differentiation of pathogens of the Enterobacteriaceae family remain challenging. In this study, Raman spectroscopy was applied for the differentiation of 24 clinical E. coli, Klebsiella pneumoniae and Klebsiella oxytoca isolates. Spectra were collected with two spectroscopic approaches: UV-Resonance Raman spectroscopy (UVRR) and single-cell Raman microspectroscopy with 532 nm excitation. A description of the different biochemical profiles provided by the different excitation wavelengths was performed followed by machine-learning models for the classification at the genus and species levels. UVRR was shown to outperform 532 nm excitation, enabling correct classification at the genus level of 23/24 isolates. Furthermore, for the first time, Klebsiella species were correctly classified at the species level with 92% accuracy, classifying all three K. oxytoca isolates correctly. These findings should guide future applicative studies, increasing the scope of Raman spectroscopy's suitability for clinical applications.

Oxidant/Antioxidant Status Is Impaired in Sepsis and Is Related to Anti-Apoptotic, Inflammatory, and Innate Immunity Alterations.

Oxidative stress is considered pivotal in the pathophysiology of sepsis. Oxidants modulate heat shock proteins (Hsp), interleukins (IL), and cell death pathways, including apoptosis. This multicenter prospective observational study was designed to ascertain whether an oxidant/antioxidant imbalance is an independent sepsis discriminator and mortality predictor in intensive care unit (ICU) patients with sepsis (n = 145), compared to non-infectious critically ill patients (n = 112) and healthy individuals (n = 89). Serum total oxidative status (TOS) and total antioxidant capacity (TAC) were measured by photometric testing. IL-6, -8, -10, -27, Hsp72/90 (ELISA), and selected antioxidant biomolecules (Ζn, glutathione) were correlated with apoptotic mediators (caspase-3, capsase-9) and the central anti-apoptotic survivin protein (ELISA, real-time PCR). A wide scattering of TOS, TAC, and TOS/TAC in all three groups was demonstrated. Septic patients had an elevated TOS/TAC, compared to non-infectious critically ill patients and healthy individuals (p = 0.001). TOS/TAC was associated with severity scores, procalcitonin, IL-6, -10, -27, IFN-γ, Hsp72, Hsp90, survivin protein, and survivin isoforms -2B, -ΔΕx3, -WT (p < 0.001). In a propensity probability (age-sex-adjusted) logistic regression model, only sepsis was independently associated with TOS/TAC (Exp(B) 25.4, p < 0.001). The AUCTOS/TAC (0.96 (95% CI = 0.93-0.99)) was higher than AUCTAC (z = 20, p < 0.001) or AUCTOS (z = 3.1, p = 0.002) in distinguishing sepsis. TOS/TAC, TOS, survivin isoforms -WT and -2B, Hsp90, IL-6, survivin protein, and repressed TAC were strong predictors of mortality (p < 0.01). Oxidant/antioxidant status is impaired in septic compared to critically ill patients with trauma or surgery and is related to anti-apoptotic, inflammatory, and innate immunity alterations. The unpredicted TOS/TAC imbalance might be related to undefined phenotypes in patients and healthy individuals.

Detection of multi-resistant clinical strains of E. coli with Raman spectroscopy.

In recent years, we have seen a steady rise in the prevalence of antibiotic-resistant bacteria. This creates many challenges in treating patients who carry these infections, as well as stopping and preventing outbreaks. Identifying these resistant bacteria is critical for treatment decisions and epidemiological studies. However, current methods for identification of resistance either require long cultivation steps or expensive reagents. Raman spectroscopy has been shown in the past to enable the rapid identification of bacterial strains from single cells and cultures. In this study, Raman spectroscopy was applied for the differentiation of resistant and sensitive strains of Escherichia coli. Our focus was on clinical multi-resistant (extended-spectrum ß-lactam and carbapenem-resistant) bacteria from hospital patients. The spectra were collected using both UV resonance Raman spectroscopy in bulk and single-cell Raman microspectroscopy, without exposure to antibiotics. We found resistant strains have a higher nucleic acid/protein ratio, and used the spectra to train a machine learning model that differentiates resistant and sensitive strains. In addition, we applied a majority of voting system to both improve the accuracy of our models and make them more applicable for a clinical setting. This method could allow rapid and accurate identification of antibiotic resistant bacteria, and thus improve public health.

Biochemical Analysis of Leukocytes after In Vitro and In Vivo Activation with Bacterial and Fungal Pathogens Using Raman Spectroscopy.

Biochemical information from activated leukocytes provide valuable diagnostic information. In this study, Raman spectroscopy was applied as a label-free analytical technique to characterize the activation pattern of leukocyte subpopulations in an in vitro infection model. Neutrophils, monocytes, and lymphocytes were isolated from healthy volunteers and stimulated with heat-inactivated clinical isolates of Candida albicans, Staphylococcus aureus, and Klebsiella pneumoniae. Binary classification models could identify the presence of infection for monocytes and lymphocytes, classify the type of infection as bacterial or fungal for neutrophils, monocytes, and lymphocytes and distinguish the cause of infection as Gram-negative or Gram-positive bacteria in the monocyte subpopulation. Changes in single-cell Raman spectra, upon leukocyte stimulation, can be explained with biochemical changes due to the leukocyte's specific reaction to each type of pathogen. Raman spectra of leukocytes from the in vitro infection model were compared with spectra from leukocytes of patients with infection (DRKS-ID: DRKS00006265) with the same pathogen groups, and a good agreement was revealed. Our study elucidates the potential of Raman spectroscopy-based single-cell analysis for the differentiation of circulating leukocyte subtypes and identification of the infection by probing the molecular phenotype of those cells.

Raman Stable Isotope Probing of Bacteria in Visible and Deep UV-Ranges.

Raman stable isotope probing (Raman-SIP) is an excellent technique that can be used to access the overall metabolism of microorganisms. Recent studies have mainly used an excitation wavelength in the visible range to characterize isotopically labeled bacteria. In this work, we used UV resonance Raman spectroscopy (UVRR) to evaluate the spectral red-shifts caused by the uptake of isotopes (13C, 15N, 2H(D) and 18O) in E. coli cells. Moreover, we present a new approach based on the extraction of labeled DNA in combination with UVRR to identify metabolically active cells. The proof-of-principle study on E. coli revealed heterogeneities in the Raman features of both the bacterial cells and the extracted DNA after labeling with 13C, 15N, and D. The wavelength of choice for studying 18O- and deuterium-labeled cells is 532 nm is, while 13C-labeled cells can be investigated with visible and deep UV wavelengths. However, 15N-labeled cells are best studied at the excitation wavelength of 244 nm since nucleic acids are in resonance at this wavelength. These results highlight the potential of the presented approach to identify active bacterial cells. This work can serve as a basis for the development of new techniques for the rapid and efficient detection of active bacteria cells without the need for a cultivation step.

Raman 18 O-labeling of bacteria in visible and deep UV-ranges.

Raman stable isotope labeling with 2 H, 13 C or 15 N has been reported as an elegant approach to investigate cellular metabolic activity, which is of great importance to reveal the functions of microorganisms in native environments. A new strategy termed Raman 18 O-labeling was developed to probe the metabolic activity of bacteria. Raman 18 O-labeling refers to the combination of Raman microspectroscopy with 18 O-labeling using H218 O. At an excitation wavelength of 532 nm, the incorporation of 18 O into the amide I group of proteins and DNA/RNA bases was observed in Escherichia coli cells, while for an excitation wavelength electronically resonant with DNA or aromatic amino acid absorption at 244 nm 18 O assimilation was detected using chemometric tools rather than visual inspection. Raman 18 O-labeling at 532 nm combined with 2D correlation analysis confirmed the assimilation of 18 O in proteins and nucleic acids and revealed the growth strategy of E. coli cells; they underwent protein synthesis followed by nucleic acid synthesis. Independent cultural replicates at different incubation times corroborated the reproducibility of these results. The variations in spectral features of 18 O-labeled cells revealed changes in physiological information of cells. Hence, Raman 18 O-labeling could provide a powerful tool to identify metabolically active bacterial cells.

Survivin and caspases serum protein levels and survivin variants mRNA expression in sepsis.

Sepsis is a dysregulated host response to infection related to devastating outcomes. Recently, interest has been shifted towards apoptotic and antiapoptotic pathobiology. Apoptosis is executed through the activation of caspases regulated by a number of antiapoptotic proteins, such as survivin. The survivin and caspases' responses to sepsis have not yet been elucidated. This is a multicenter prospective observational study concerning patients with sepsis (n = 107) compared to patients with traumatic systemic inflammatory response syndrome (SIRS) (n = 75) and to healthy controls (n = 89). The expression of survivin was quantified through real-time quantitative polymerase chain reaction for the different survivin splice variants (wild type-WT, ΔEx3, 2B, 3B) in peripheral blood leukocytes. The apoptotic or antiapoptotic tendency was specified by measuring survivin-WT, caspase-3, and -9 serum protein concentrations through enzyme-linked immunosorbent assay. The survivin-WT, -2B, -ΔΕx3 mRNA, survivin protein, and caspases showed an escalated increase in SIRS and sepsis, whereas survivin-3B was repressed in sepsis (p < 0.05). Survivin correlated with IL-8 and caspase-9 (p < 0.01). For discriminating sepsis, caspase-9 achieved the best receiver operating characteristic curve (AUROC) of 0.95. In predicting mortality, caspase-9 and survivin protein achieved an AUROC of 0.70. In conclusion, specific apoptotic and antiapoptotic pathways might represent attractive targets for future research in sepsis.

Susceptibility profiles and clinical efficacy of antifungals against candida bloodstream isolates from critically ill patients: Focus on intravenous itraconazole.

In vitro and clinical data were analysed to evaluate the susceptibility profile of itraconazole in light of the new cut-off points. The in vitro activity of itraconazole was compared with that of eight comparators against 119 Candida bloodstream isolates from 2015 to 2018. Minimum inhibitory concentrations (MICs) were measured by the colorimetric MICRONAUT-S assay. The content of wells without any color change was sub-cultured to measure killing efficacy. No major differences were found against Candida albicans. Itraconazole, posaconazole and amphotericin B were the most active agents against Candida parapsilosis. Of the 32 isolates of C. parapsilosis that were resistant to fluconazole, 96.9%, 78.1% and 93.8% were susceptible to itraconazole, voriconazole and posaconazole, respectively. The ratio of the minimum fungicidal concentration (MFC) to the MIC of itraconazole was lower than for the other azoles against C. parapsilosis and C. glabrata. Itraconazole achieved greater inhibition over-time of the growth of C. parapsilosis than fluconazole. Seventy-three critically ill patients who were unresponsive to antibiotics received intravenous empirical treatment with itraconazole (n = 28) or comparators (n = 45). Case-control matching was conducted for severity, comorbidities, risk factors for candidemia, administered antibiotics and days of antifungal treatment. Breakthrough candidemia was found in 3.6% of patients treated with itraconazole and in 32.1% of patients treated with comparators (P: 0.020); breakthrough candidemia by C. parapsilosis was found in 3.6% and 28.6% of patients, respectively. Results indicate that itraconazole retains a valuable susceptibility profile against Candida isolates, particularly C. parapsilosis. This superior profile may explain the clinical efficacy in the occurrence of breakthrough candidemia and warrants further clinical investigation.

Association of the early absolute CD64-expressing neutrophil count and sepsis outcome.

To evaluate the early absolute CD64/CD15/CD45 neutrophil count as a marker of prognosis of sepsis outcome the absolute CD64/CD15/CD45 count was measured by flow cytometry in 65 patients with confirmed or suspected Gram-negative sepsis and organ dysfunction. Serum interleukin(IL)-8 and interferon-gamma (IFNγ) were measured by an enzyme immunoassay. An absolute count lower than 2500 cells/mm3 could early discriminate non-survivors with sensitivity 82.9% (OR 3.46, 95%CIs 1.10-10.95, p 0.042). After forward step-wise Cox- regression analysis, it was found that acute coagulopathy, acute renal injury, and an early absolute CD64/CD15/CD45 count lower than 2500/mm3 were independently associated with unfavorable outcome. The OR for death among patients with an absolute CD64/CD15/CD45 neutrophil count greater than 2500/mm3 and circulating IL-8 greater than 95 pg/ml was 0.44; this was significantly increased to 7.44 among patients with an absolute CD64/CD15/CD45 neutrophil count lower than 2500/mm3 (p 0.045 by the Breslow-Day's test; p 0.046 by the Tarone's test). An absolute CD64/CD15/CD45 count below 2500/mm3 can be a useful prognosticator of sepsis outcome and a probable indicator of sepsis immunosuppression.

Early changes of the heat-shock protein 60 to 70 ratio as prediction of miscarriage in pregnancy.

PROBLEM: To study the balance of circulating heat shock protein (HSP)60 and HSP70 in pre-term delivery. METHOD OF STUDY: A two-stage approach was used. At first stage, we run retrospective analysis of prospective collected clinical data, and at a second stage, we studied an animal model of pre-term delivery (PTD). Blood samples were collected for prenatal screening in 3629 women. Samples from 23 women with miscarriage before gestational week 21 and 53 well-matched comparators for age, body mass index, parity, and previous miscarriage with full-term pregnancy were depicted. Women with risk factors were excluded. HSP60 and HSP70 were measured by an enzyme immunosorbent assay. PTD was induced after injection of low dose of bacterial lipopolysaccharide; mice were killed for the measurement of HSP60 and HSP70 in blood and tissues. The study endpoint was the association of the HSP60 to HSP70 ratio to miscarriage. RESULTS: A ratio >6 could distinguish between women who will miscarry from women with term pregnancies with sensitivity 60%, specificity 81.8%, positive predictive value 81.8%, and negative predictive value 60% (OR: 6.750, P = 0.025). Mice of the LPS-group PTD had this ratio significantly increased in maternal serum, placentas, and embryos compared to the sham-operation group. Gene expression of hsp60/70 remained in tissues unaltered. CONCLUSION: A HSP60/HSP70 ratio equal to or more than 6 until gestational week 12 is accompanied with great likelihood for miscarriage. A similar ratio applies in an animal model of PTD induced by low-dose LPS.

Correction to: Effect of a Preparation of Four Probiotics on Symptoms of Patients with Irritable Bowel Syndrome: Association with Intestinal Bacterial Overgrowth.

The original version of this article contained mistakes, and the authors would like to correct them. The correct details are given below.

Effect of a Preparation of Four Probiotics on Symptoms of Patients with Irritable Bowel Syndrome: Association with Intestinal Bacterial Overgrowth.

The effect of probiotics on small intestinal bacterial overgrowth (SIBO) in irritable bowel syndrome (IBS) has never been studied so far. In this prospective trial, five patients with IBS and SIBO and 21 patients with IBS without SIBO were administered an oral capsule containing Saccharomyces boulardii, Bifidobacterium lactis, Lactobacillus acidophilus, and Lactobacillus plantarum (Lactolevure®) every 12 h for 30 days. SIBO was defined by quantitative culture of the third part of the duodenum; IBS was defined by the Rome III criteria. Severity of symptoms was graded by the IBS severity scoring system (SSS). The primary study endpoint was the efficacy of probiotics in improvement of symptoms of IBS in patients with SIBO. Thirty days after the end of treatment, a 71.3% decrease of the total IBS score was detected in patients with IBS and SIBO compared to 10.6% in those without SIBO (p 0.017). A similar decrease was achieved among patients with constipation-predominant IBS without SIBO. Post-treatment satisfaction from bowel function was greater in patients with SIBO. Similar satisfaction improvement was found among patients with diarrhea-predominant IBS irrespective from SIBO; pain intensity score decreased in patients with constipation-predominant IBS irrespective from SIBO. The benefit of probiotics was greater among patients with a pro-inflammatory cytokine pattern in the duodenal fluid. This is the first study that prospectively demonstrated superior clinical efficacy of probiotics in patients with IBS with SIBO. Analysis also showed considerable benefit from probiotic intake regarding certain symptoms of patients with diarrhea-predominant and constipation-predominant IBS.Trial registration: ClinicalTrials.gov identifier NCT02204891.

Increases in inflammatory and CD14dim/CD16pos/CD45pos patrolling monocytes in sepsis: correlation with final outcome.

BACKGROUND: Evidence on the changes in the absolute counts of monocyte subpopulations in sepsis is missing. METHODS: Firstly, absolute counts of circulating CD14pos/HLA-DRpos/CD45pos monocytes were measured by flow cytometry in 70 patients with Gram-negative sepsis and in 10 healthy volunteers. In the second phase, immunophenotyping was performed and the absolute count of circulating inflammatory monocytes and of circulating CD14dim/CD16pos/CD45pos patrolling monocytes were measured in another 55 patients and 10 healthy volunteers. Measurements were repeated on days 3, 7, and 10. Results were correlated with survival after 28 days. RESULTS: Greater numbers of CD14pos/HLA-DRpos/CD45pos monocytes were found on day 1 in survivors compared to nonsurvivors (p = 0.030). Receiver operating characteristic (ROC) analysis showed that a cutoff higher than 337 cells/mm3 on day 1 could discriminate between survivors and nonsurvivors with a positive predictive value (PPV) of 91.1%. Logistic regression including Sequential Organ Failure Assessment (SOFA) score and Acute Physiology and Chronic Health Evaluation (APACHE) II score showed that an absolute count greater than 337 cells/mm3 was independently associated with unfavorable outcome (odds ratio (OR) 0.19, p = 0.050). The absolute counts of inflammatory and of CD14dim/CD16pos/CD45pos monocytes were greater in patients than healthy controls during the entire 10 days of follow-up. The absolute counts on day 3 of CD14dim/CD16pos/CD45pos monocytes were greater in survivors than nonsurvivors (p = 0.027). ROC analysis revealed that the cutoff at 27 cells/mm3 could discriminate between survivors and nonsurvivors with PPV of 94.1%. Logistic regression including age, SOFA score, and APACHE II score showed that an absolute count greater than 27 cells/mm3 was independently associated with unfavorable outcome (OR 0.06, p = 0.033). Logistic regression analysis showed that intra-abdominal infection on day 1 was predictive of low CD14dim/ CD16pos/CD45pos count on day 3. CONCLUSION: Circulating counts of inflammatory and patrolling monocytes are greatly increased in Gram-negative sepsis. Absolute counts of CD14pos/HLA-DRpos/CD45pos monocytes on day 1 and CD14dim/CD16pos/CD45pos monocytes on day 3 are independently associated with final outcome. TRIAL REGISTRATION: ClinicalTrials.gov, NCT01223690 . Registered retrospectively on 18 October 2010.

How well does qSOFA correspond to underlying systemic inflammatory response?

Need for prompt recognition and management of sepsis recently led to the introduction of qSOFA score. However, its association with underlying host inflammatory response remains unclear, while previous studies have challenged its performance in non - intensive care unit (ICU) patients comparing to previously used systemic inflammatory response syndrome (SIRS) criteria. Between June 2016 and April 2017, we performed a prospective observational study in the medical ward of a tertiary hospital to explore the relation of qSOFA ≥ 2 and <2 to underlying inflammatory response, as this is mirrored in levels of serum pro- and anti-inflammatory mediators i.e. IL-6, IL-10 and TNF-α. A total of 100 consecutive patients were finally included in this study. Comparable levels [(pg/ml) median (IQR)] of IL-6 [200 (53-200) vs 65.1 (17.3-200)], IL-10 [ 7 (2.3-170.6) vs 2.3 (2.3-27.7)], and TNF-α [4 (4-46.1) vs 46.06 (4-227.2)] were noted between group of patients with qSOFA ≥ 2 or <2. Nevertheless, prognosis was worse in patients with qSOFA ≥ 2 showing longer length of stay [10 (7-25) vs 5 (3-7) days, p = .03] and lower recovery rates (41 vs 93%, p < .0001). Our results underline the need for prompt management of critically ill patients in presence of systemic inflammatory response regardless of qSOFA score, partly reflecting its low sensitivity comparing to previously used SIRS criteria.

MABp1 Targeting IL-1α for Moderate to Severe Hidradenitis Suppurativa Not Eligible for Adalimumab: A Randomized Study.

Patients with moderate to severe hidradenitis suppurativa failing adalimumab therapy, or those ineligible to receive it, remain a population with an unmet need. Twenty patients not eligible for adalimumab were randomized to receive 12 weeks of blind treatment with placebo or MABp1, a true human antibody targeting IL-1α. Hidradenitis suppurativa clinical response score at week 12 was the primary endpoint. The primary endpoint was met in 10% and 60% of placebo- and MABp1-treated patients, respectively (odds ratio = 13.50, 95% confidence interval = 1.19-152.51). Clinical efficacy was maintained at 24 weeks in 0% and 40%. Improvement in the visual analog scale was reported by 20% and 85.7%, respectively, of patients failing previous anti-TNF treatment. Ultrasonography showed decreased neovascularization and lesion skin depth in the MABp1 group. MABp1 treatment was associated with decrease of circulating IL-8 and of stimulated production of IL-8 by whole blood. Whole blood production for hBD-2 was negatively associated with changes on ultrasonography in the placebo group but not in the MABp1 group. MABp1 is a promising treatment for patients with hidradenitis suppurativa not eligible for adalimumab. Inhibition of neovascularization and modulation of the production of IL-8 and hBD-2 are suggested mechanisms of action.

Platelet reactivity in sepsis syndrome: results from the PRESS study.

Platelet activation mediates systemic inflammatory response during infection. However, data on platelet reactivity (PR) varies among different settings. We assessed PR along different stages of sepsis and tried to predict for determinants of its variance. In parallel, we evaluated it as an early bedside diagnostic biomarker. This was an observational prospective cohort study. Incoming patients were assorted to distinct groups of uncomplicated infection, sepsis, and severe sepsis/septic shock. A control group of healthy volunteers was used as comparison. PR was assessed using the bedside point-of-care VerifyNow assay, in P2Y12 reaction units (PRU) alongside with levels of major inflammatory markers and whole blood parameters. A total of 101 patients and 27 healthy volunteers were enrolled. PR significantly and reversibly increases during sepsis compared to uncomplicated infection and healthy controls (244 ± 66.7 vs 187.33 ± 60.98, p < 0.001 and 192.17 ± 47.51, p < 0.001, respectively). In severe sepsis, PR did not significantly differ compared to other groups. Sepsis stage uniquely accounts for 15.5% of PR in a linear regression prediction model accounting for 30% of the variance of PR (F = 8.836, p < 0.001). PRU >253 had specificity of 91.2% and sensitivity of 40.8% in discriminating septic from non-septic patients. The addition of PRU to SOFA and qSOFA scores significantly increased their c-statistic (AUC SOFA + PRU, 0.867 vs SOFA, 0.824, p < 0.003 and AUC qSOFA + PRU, 0.842 vs qSOFA, 0.739, p < 0.001), making them comparable (AUC SOFA + PRU vs qSOFA + PRU, p = 0.4). PR significantly and reversibly increases early in sepsis, but seems to exhaust while disease progresses. Bedside assessment of PR can provide robust discriminative accuracy in the early diagnosis of septic patients.