Iodine contrast agents do not influence Platelet-Rich Plasma function at an early time point in vitro

BACKGROUND: Iodine contrast agents (ICAs) are routinely used by radiologists to help guide intra-articular infiltrations. The aim of this study was to assess the in vitro effects of ICA on platelet function of human autologous Platelet-Rich Plasma (PRP). METHODS: One hundred thirty-seven consecutive patients with symptomatic femoral-patellar osteoarthritis were included. All were addressed to our institution for a fluoroscopy-guided intra-articular PRP infiltration of the pathological femoral-patellar joint. For each patient, 500 μl of PRP were sampled before intra-articular injection. First, PRP samples were mixed with 50 μl of 2 widely used ICA: Visipaque270® (Iodixanol, n = 58) and Iopamiron200® (Iopamidol, n = 69). PRP concentration ([PRP]) was measured at different delays of incubation (t = 0, 5, 10, 15, 20 and 30 min) enabling to calculate PRP ratio (defined as [PRP](t)/[PRP](0mn)) at each delay, for each mixture, in order to quantitatively assess the influence of ICA on PRP ratio. Second, the PRP samples of 10 additional patients were mixed with Visipaque270®, Visipaque270®, Iopamiron200® and phosphate buffer saline (PBS: control solution) in order to qualitatively assess the influence of ICA on platelet aggregation, using ADP, Collagen, Arachidonic acid and TRAP tests. The surface expression of human P-selectin, a marker of α-granule release, in the PRP + Visipaque270® and PRP + Iopamiron200® mixtures was finally compared. Repeated-measures ANOVA, classical 2-way ANOVA and Wilcoxon matched-pairs test were used to study the influence of ICA on PRP quality. RESULTS: There was no significant change in PRP ratio during the first 30mn of incubation (p = 0.991) whatever the ICA (p = 0.926). Whatever the aggregation test, there was no significant difference in the percentage of platelet aggregation between PRP + PBS, PRP + Visipaque270® and PRP + Iopamiron200® (p = 0.998), nor between PRP + PBS and PRP + Visipaque320® (p = 0.470). Finally, there was no significant difference in P-selectin expression between the PRP + Visipaque270® and PRP + Iopamiron200® mixtures (p = 0.500). CONCLUSION: At early delays of incubation, Visipaque® and Iopamiron®, which are two widely used ICA for intra-articular infiltrations, did not influence the in vitro platelet function nor the quality of PRP

suPAR remains uninfluenced by surgery in septic patients with bloodstream infection

Surgical trauma induces activation of the immune system and may cause an increase of inflammatory biomarkers tested postoperatively in septic patients treated for bloodstream infection. The aim of this study was to determine the impact of surgical interventions on the novel sepsis biomarker soluble urokinase plasminogen activator receptor (suPAR) and to compare results with those of routine laboratory parameters CRP, PCT, and IL-6 in patients with culture-proven bloodstream infection. Forty-six adult patients with positive blood culture undergoing minor or major surgical intervention were investigated, 12 blood culture positive patients served as control group. Blood was collected 24 hours before and after surgical intervention for determination of the sepsis biomarkers suPAR, CRP, PCT, and IL-6. Within the surgical study cohort, a non-significant increase of suPAR, CRP, and PCT was observed postoperatively (p 0.642; p 0.773; p 0.087). In contrast, a slight decrease of IL-6 (p 0.599) was observed. A significant correlation was calculated for the pre- and postoperative difference of CRP (p 0.028) and PCT (p 0.008) and type of surgical intervention received: after minor surgical intervention only PCT decreased significantly (p <0.001), while after major surgical interventions no significant differences were observed for all biomarkers evaluated. In the control group, a significant decrease of CRP (p 0.005) and PCT (p 0.005) was observed. In patients treated adequately for bloodstream infections, postoperative suPAR levels remained uninfluenced of the surgical trauma and might therefore be a reliable parameter for postoperative infectious monitoring. After minor surgical intervention, PCT seems to be the most reliable parameter

Characterisation of <i>Candida</i> within the Mycobiome/Microbiome of the Lower Respiratory Tract of ICU Patients

<div><p>Whether the presence of <i>Candida spp</i>. in lower respiratory tract (LRT) secretions is a marker of underlying disease, intensive care unit (ICU) treatment and antibiotic therapy or contributes to poor clinical outcome is unclear. We investigated healthy controls, patients with proposed risk factors for <i>Candida</i> growth in LRT (antibiotic therapy, ICU treatment with and without antibiotic therapy), ICU patients with pneumonia and antibiotic therapy and candidemic patients (for comparison of truly invasive and colonizing <i>Candida spp</i>.). Fungal patterns were determined by conventional culture based microbiology combined with molecular approaches (next generation sequencing, multilocus sequence typing) for description of fungal and concommitant bacterial microbiota in LRT, and host and fungal biomarkes were investigated. Admission to and treatment on ICUs shifted LRT fungal microbiota to <i>Candida spp</i>. dominated fungal profiles but antibiotic therapy did not. Compared to controls, <i>Candida</i> was part of fungal microbiota in LRT of ICU patients without pneumonia with and without antibiotic therapy (63% and 50% of total fungal genera) and of ICU patients with pneumonia with antibiotic therapy (73%) (p<0.05). No case of invasive candidiasis originating from <i>Candida</i> in the LRT was detected. There was no common bacterial microbiota profile associated or dissociated with <i>Candida spp</i>. in LRT. Colonizing and invasive <i>Candida</i> strains (from candidemic patients) did not match to certain clades withdrawing the presence of a particular pathogenic and invasive clade. The presence of <i>Candida spp</i>. in the LRT rather reflected rapidly occurring LRT dysbiosis driven by ICU related factors than was associated with invasive candidiasis.</p></div

Relative abundance of fungal microbiota in consecutively sampled patients.

<p>Consecutive lower respiratory tract samples of 4 intubated and mechanically ventilated patients with pneumonia. Fungi are shown at genus level. Yellow bars represent <i>Candida</i> species. VAP = Ventilator associated pneumonia, ASP = aspiration pneumonia, NAP = nosocomial acquired pneumonia.</p