Endothelial damage in septic shock patients as evidenced by circulating syndecan-1, sphingosine-1-phosphate and soluble VE-cadherin: a substudy of ALBIOS.

BACKGROUND: Septic shock is characterized by breakdown of the endothelial glycocalyx and endothelial damage, contributing to fluid extravasation, organ failure and death. Albumin has shown benefit in septic shock patients. Our aims were: (1) to identify the relations between circulating levels of syndecan-1 (SYN-1), sphingosine-1-phosphate (S1P) (endothelial glycocalyx), and VE-cadherin (endothelial cell junctions), severity of the disease, and survival; (2) to evaluate the effects of albumin supplementation on endothelial dysfunction in patients with septic shock. METHODS: This was a retrospective analysis of a multicenter randomized clinical trial on albumin replacement in severe sepsis or septic shock (the Albumin Italian Outcome Sepsis Trial, ALBIOS). Concentrations of SYN-1, S1P, soluble VE-cadherin and other biomarkers were measured on days 1, 2 and 7 in 375 patients with septic shock surviving up to 7 days after randomization. RESULTS: Plasma concentrations of SYN-1 and VE-cadherin rose significantly over 7 days. SYN-1 and VE-cadherin were elevated in patients with organ failure, and S1P levels were lower. SYN-1 and VE-cadherin were independently associated with renal replacement therapy requirement during ICU stay, but only SYN-1 predicted its new occurrence. Both SYN-1 and S1P, but not VE-cadherin, predicted incident coagulation failure. Only SYN-1 independently predicted 90-day mortality. Albumin significantly reduced VE-cadherin, by 9.5% (p = 0.003) at all three time points. CONCLUSION: Circulating components of the endothelial glycocalyx and of the endothelial cell junctions provide insights into severity and progression of septic shock, with special focus on incident coagulation and renal failure. Albumin supplementation lowered circulating VE-cadherin consistently over time. CLINICAL TRIAL REGISTRATION: ALBIOS ClinicalTrials.gov number NCT00707122.

Colistin-associated Acute Kidney Injury in Severely Ill Patients: A Step Toward a Better Renal Care? A Prospective Cohort Study.

BACKGROUND: Critically ill patients with severe sepsis or septic shock may need relatively high colistin daily doses for efficacy against multidrug-resistant and extensively drug-resistant gram-negative rods. However, acute kidney injury (AKI) may represent a major dose-limiting adverse effect of colistin. We sought to determine AKI occurrence and to identify factors influencing AKI risk in severely ill patients receiving colistin according to a recently proposed dosing strategy. METHODS: A prospective, observational, cohort study involving patients with severe sepsis or septic shock who received colistin was performed. AKI was defined according to Acute Kidney Injury Network criteria. Colistin administration was driven by a modified pharmacokinetics-pharmacodynamics (PK/PD)-based dosing approach. RESULTS: Of 70 patients who received colistin at a median daily dose of 9 million IU (MIU; interquartile range, 5.87-11.1 MIU), 31 (44%) developed AKI. In univariate analysis, age, Acute Physiology and Chronic Health Evaluation (APACHE) II score, Sequential Organ Failure Assessment (SOFA), score and baseline renal impairment were significantly associated with AKI. Moreover, patients with AKI were less frequently treated with adjuvant ascorbic acid (P = .003). In multivariate analysis, independent predictors of AKI were baseline renal impairment (adjusted hazard ratio, 4.15; 95% confidence interval, 1.9-9.2; P < .001) and age (1.03; 1.0-1.05; P = .028), whereas a strong independent renal-protective role emerged for ascorbic acid (0.27; .12-.57; P < .001). CONCLUSIONS: In severely ill patients receiving colistin according to a PK/PD-driven dosing approach, baseline renal impairment and older age strongly predict AKI occurrence, but concomitant administration of ascorbic acid markedly reduces AKI risk, allowing safer use of colistin.

High-dose, extended-interval colistin administration in critically ill patients: is this the right dosing strategy? A preliminary study.

BACKGROUND: Gram-negative bacteria susceptible only to colistin (COS) are emerging causes of severe nosocomial infections, reviving interest in the use of colistin. However, consensus on the most effective way to administer colistin has not yet been reached. METHODS: All patients who had sepsis due to COS gram-negative bacteria or minimally susceptible gram-negative bacteria and received intravenous colistimethate sodium (CMS) were prospectively enrolled. The CMS dosing schedule was based on a loading dose of 9 MU and a 9-MU twice-daily fractioned maintenance dose, titrated on renal function. For each CMS course, clinical cure, bacteriological clearance, daily serum creatinine clearance, and estimated creatinine clearance were recorded. RESULTS: Twenty-eight infectious episodes due to Acinetobacter baumannii (46.4%), Klebsiella pneumoniae (46.4%), and Pseudomonas aeruginosa (7.2%) were analyzed. The main types of infection were bloodstream infection (64.3%) and ventilator-associated pneumonia (35.7%). Clinical cure was observed in 23 cases (82.1%). Acute kidney injury developed during 5 treatment courses (17.8%), did not require renal replacement therapy, and subsided within 10 days from CMS discontinuation. No correlation was found between variation in serum creatinine level (from baseline to peak) and daily and cumulative doses of CMS, and between variation in serum creatinine level (from baseline to peak) and duration of CMS treatment. CONCLUSIONS: Our study shows that in severe infections due to COS gram-negative bacteria, the high-dose, extended-interval CMS regimen has a high efficacy, without significant renal toxicity.