Evaluation of vancomycin pharmacokinetics in patients with augmented renal clearances: A randomized clinical trial.

Purpose: Vancomycin is a narrow therapeutic window glycopeptide antibiotic that acts against Gram-positive bacteria. As it is renally eliminated, therapeutic drug monitoring is recommended for vancomycin, especially in case of kidney function alteration. Augmented renal clearance (ARC), defined as a creatinine clearance of more than 130 ml/min, is a risk factor for sub-therapeutic concentrations of vancomycin. This study aimed to evaluate the vancomycin pharmacokinetics following the administration of two different regimens in ARC patients. Methods: A randomized clinical trial (IRCT20180802040665N1) was conducted on patients in need of vancomycin therapy. Eight hours of urine was collected and 56 patients divided into two groups with creatinine clearance of more than 130 ml/min were included in the study. The first group received 15 mg/kg of vancomycin every 12 h and the second group 15 mg/kg every 8 h. After four doses, the peak and trough concentrations were measured from two blood samples. The primary outcome was the percentage of patients who attainted AUC more than 400. The occurrence of acute kidney injury also was evaluated after seven days. Results: The mean age of patients in the every 12 h and every 8 h groups was 44.04 ± 16.55 and 42.86 ± 11.83 years, respectively. While neurosurgical issues were the most common causes of hospitalization, central nervous infections were the most common indications for vancomycin initiation. Urinary creatinine clearance was 166.94 ± 41.32 ml/min in the every 12 h group and 171.78 ± 48.56 ml/min in the every 8 h group. 46.42% of patients in the every 12 h group and 82.14% of patients in the every 8 h group attained AUC/MIC of more than 400 mg × hr/L. None of the patients in the every 12 h group reached more than 15 mcg/ml concentration. At the 7-day follow-up, 10.7% patients in the BD group and 28.6% patients in the TDS group developed acute kidney injury (p = 0.089). Conclusion: Administration of vancomycin at a dose of 15 mg/kg every 8 h is associated with higher pharmacokinetic attainment in ARC patients. The occurrence of acute kidney injury also was not significantly higher in this therapeutic regimen. AUC/MIC monitoring is necessary in this population.

Investigation of pharmacokinetic and clinical outcomes of various meropenem regimens in patients with ventilator-associated pneumonia and augmented renal clearance.

INTRODUCTION: Augmented renal clearance (ARC) defined as creatinine clearance (Clcr) above 130 mL/min/1.73m2 may lead to suboptimal antibacterial treatment. The aim of this study was to determine a strategy for meropenem administration to achieve both pharmacodynamic-pharmacokinetic (PK-PD) target (50%fT > MIC) and better clinical outcomes in patients with VAP and ARC. MATERIALS AND METHODS: In this randomized clinical trial, patients with VAP and high risk for ARC were recruited. An 8-h urine collection was performed on the 1st, 3rd, and 5th days of study to measure Clcr. Included patients were divided into three groups: (1) 1 g meropenem, 3-h infusion, (2) 2 g meropenem, 3-h infusion, (3) 1 g meropenem, 6-h infusion. On the 2nd, 3rd, and 5th days of treatment, peak and trough blood samples were collected to undergo HPLC assay. MICs were assessed using microdilution method. Patients were also clinically monitored for 14 days. RESULTS: Forty-five patients were included. Group 3 showed significanty higher rate of patients achieving fT > MIC > 50% (100% for group 3 versus 40% for group 2 and 13% for group 1; p = 0.0001). Mean fT > MIC% was significantly higher in group 3 (78.77 ± 5.87 for group 3 versus 49.6 ± 7.38 for group 2 and 43.2 ± 7.98 for group 1; p = 0.0001). Statistical analysis showed no significant differences among groups regarding clinical improvement. CONCLUSION: According to the findings of this trial, prolonged meropenem infusion is an appropriate strategy compared to dose elevation among ARC patients.

Study of the Effects of N-acetylcysteine on Inflammatory Biomarkers and Disease Activity Score in Patients with Rheumatoid Arthritis.

Rheumatoid arthritis (RA) is considered as an autoimmune-related condition in which the overproduction of pro-inflammatory cytokines leads to an inflammatory cascade. N-acetylcysteine (NAC) is a potent anti-inflammatory and anti-oxidant agent. We aimed to explore the impact of oral NAC on cytokines activities and clinical indicators in RA patients. In this placebo-controlled randomized double-blind clinical trial, 41 active RA patients were allocated in either NAC (600 mg, twice a day) or placebo group, as add-on therapy to the routine regimen, for 8 weeks. Disease activity score with an erythrocyte sedimentation rate (DAS28-ESR), and serum concentrations of interleukin (IL)-1ß and IL-17 were assessed at baseline and end of the trial for all participants in the test and control groups. The reduction of the DAS28-ESR was higher considerably in the NAC group compared to that of the control group. No statistically significant differences were seen in the reduction of IL-1ß and IL-17 cytokines between the NAC and control groups. In addition, improvements in the patient global assessment, number of tender joints, number of swollen joints, and the ESR rates were in favor of the NAC group. Our findings reveal that NAC may have a beneficial effect on all of the clinical features of RA. However, non-significant variations in the IL-1ß and IL-17 levels suggest an alternative way of NAC effectiveness without influencing the measured cytokines. Nevertheless, these results need to be confirmed by further investigations.

Association Between Delayed Graft Function (DGF) Biomarkers and Long-term Outcomes After Living Donor Kidney Transplantation.

BACKGROUND AND OBJECTIVES: The association between preoperative Urine Neutrophil Gelatinase-associated Lipocalin (uNGAL) and interleukin-18 (uIL-18) with poor 1-year allograft function has been shown in deceased-donor kidney transplant recipients previously, and also these markers could predict 3-month allograft function. However, it is unknown whether there is an association between these postoperative biomarkers with important recipient outcomes beyond this time in livedonor transplants. METHODS: NGAL and IL-18 four and 24 hours were measured in live-donor kidney transplant recipients after transplantation. The relationships between changes in these markers with clinical outcomes as well as kidney function were examined at 1 month and 2 years. Moreover, the association between delayed graft function with clinical outcome and Serum Creatinine (SrCr) was evaluated during this period. RESULTS: The Mean age for kidney recipients was 23.9 years. Significant interaction was observed between uNGAL 24 hr (pvalue=0.01) and uIL-18 four and 24 hr after transplantation (pvalue=0.04, 0.03; respectively) with patients' outcome after 1 month and changes in uNGAL with outcomes after 2 years (pvalue= 0.04). CONCLUSION: Changes in urine NGAL postoperative are associated with worst outcomes, 2 years after kidney transplantation, suggesting its potential role in identifying patients that are at high risk for diminished allograft function, outcome and survival.

N-acetylcysteine decreases urinary level of neutrophil gelatinase-associated lipocalin in deceased-donor renal transplant recipients: a randomized clinical trial.

CONTEXT: Acute kidney injury (AKI) is a common complication after kidney transplantation (KT), especially in recipients from deceased donors. Urinary neutrophil gelatinase-associated lipocalin (u-NGAL) is an early and sensitive marker of AKI after transplantation. OBJECTIVES: We assessed the renoprotective effect of N-acetylcysteine (NAC) on u-NGAL levels as an early prognostic marker of graft function immediately after transplantation. MATERIALS AND METHODS: A double-blind, randomized, placebo-controlled trial was conducted on 70 deceased-donor KT recipients ( www.irct.ir , trial registration number: IRCT2014090214693N4). Patients received 600 mg oral NAC or placebo twice daily from day 0 to 5 and urine samples were taken before, and on the first and fifth days after transplantation. U-NGAL and early graft function were compared between the two groups. RESULTS: NAC significantly reduced u-NGAL levels compared to placebo (p value = 0.02), while improvement in early graft function with NAC did not reach statistical significance. CONCLUSIONS: This study showed that NAC administration in deceased-donor KT recipients can reduce tubular kidney injury, evidenced by u-NGAL measurements. Improvement in early graft function needs a larger sample size to reach a statistical conclusion.

The study of vitamin D administration effect on CRP and Interleukin-6 as prognostic biomarkers of ventilator associated pneumonia.

PURPOSE: In regard with the effect of immune-stimulants in the treatment of infectious diseases, the effect of vitamin D administration on the outcome of patients with Ventilator-Associated Pneumonia (VAP) with a high rate of mortality, was studied. MATERIAL AND METHOD: In this trial, 46 adult patients suffering from VAP and vitamin D deficiency were enrolled. The first group of patients received single intramuscular injection of vitamin D (300000Unit), while the other group were given the placebo. RESULTS: Administration of vitamin D significantly enhanced its levels (P<0.0001) in the treated patients (12.28±8.26) in comparison with placebo group (1.15±1.50). Serum Interleukin-6 levels were significantly reduced in the treated group compared to placebo (P=0.01). Although C-Reactive protein (CRP) levels showed an improving trend in the vitamin D group, no significant difference between groups (P=0.12) was found. Interestingly, the mortality rate of patients that treated with vitamin D (5/24) was significantly lower (p=0.04) than that of the placebo group (11/22). CONCLUSION: Our results indicate that vitamin D administration can significantly reduce the IL-6 as prognostic marker in VAP patients, and must be considered as adjunct option in the treatment of VAP patients.

Evaluation of Renal Toxicity of Colistin Therapy With Neutrophil Gelatinase-associated Lipocalin: a Biomarker of Renal Tubular Damage.

INTRODUCTION: Nephrotoxicity has been a concern with new dosing regimens of colistin. This study was designed to compare nephrotoxicity of high dose and conventional dose of colistin and the ability of detecting it using neutrophil gelatinase-associated lipocalin (NGAL). MATERIALS AND METHODS: A randomized clinical trial was carried out on 40 patients with multidrug-resistant gram-negative infections assigned into 2 groups to receive high and conventional doses of colistin. Blood samples were taken 4 times for measuring serum NGAL. The incidence of acute kidney injury was also evaluated based on the risk, injury, failure, loss, end-stage renal disease (RIFLE) criteria. RESULTS: Baseline levels of NGAL were not significantly different between the patients on the high dose and conventional dose of colistin. The mean NGAL levels on day 10 were 762.14 ± 415.44 pg/mL and 623.67 ± 272.61 pg/mL, respectively.  However, between-group analysis did not show a significant difference in the NGAL levels. The prevalence of acute kidney injury was 60% and 15% based on the RIFLE criteria, in the high-dose and conventional-dose groups, respectively (P = .003). CONCLUSIONS: Although colistin-induced nephrotoxicity was not confirmed with NGAL levels, our findings, however, showed a higher incidence of acute kidney injury associated with high-dose colistin, defined by the RIFLE criteria. Higher levels of NGAL in the acute kidney injury patients were associated with high-dose regimen of colistin.

Nephrotoxicity of High and Conventional Dosing Regimens of Colistin: A Randomized Clinical Trial.

Nephrotoxicity has been a major long-standing concern about colistin.This study was designed to compare nephrotoxicity of high dose and conventional dose of colistin. A randomized open-labeled clinical trial on 40 patients with multi-drug resistant gram negative infections was designed. Patients were allocated into two equal-size groups receiving high (a loading dose of 9 million international units (MIU) and maintenance doses of 4.5 MIU every 12 h) and conventional dose (2 MIU every 8 h) of colistin. Blood samples were taken on day 1, 3, 5, 7 and 10 of treatment for measuring serum cystatin C (Cys C) levels. Incidence of acute kidney injury (AKI) was also evaluated based on RIFLE criteria. Mean ± sd of the difference between baseline and day 10 Cys C levels in high dose and conventional dose groups were 1.61 ± 0.90 and 1.32 ± 0.48, respectively (P = 0.30). Within group analysis showed increase in Cys C levels in both groups (P = 0.001),however, no significant difference in Cys C levels was seen in between groups analysis (P = 0.13). Prevalence of AKI based on RIFLE criteria was 60% and 15% in high dose and conventional dose groups, respectively (P = 0.003). Comparison of Cys C between AKI (mean ± sd) and non-AKI (mean ± sd) patients, irrespective of colistin dosage regimens, confirmed a significant difference (P < 0.0001). Although, colistin-induced nephrotoxicity, determined by Cys C levels, was not confirmed by our findings, however, higher incidence of AKI in high-dose group, defined by RIFLE criteria, along with higher levels of Cys C in AKI patients are supportive of the higher risk of renal toxicity associated with high-dose regimen of colistin. More RCTs with a larger sample size are recommended.

S100 B: A new concept in neurocritical care.

After brain injuries, concentrations of some brain markers such as S100B protein in serum and cerebrospinal fluid (CSF) are correlated with the severity and outcome of brain damage. To perform an updated review of S100B roles in human neurocritical care domain, an electronic literature search was carried among articles published in English prior to March 2017. They were retrieved from PubMed, Scopus, EMBSCO, CINAHL, ISC and the Cochrane Library using keywords including "brain", "neurobiochemical marker", "neurocritical care", and "S100B protein". The integrative review included 48 studies until March 2017. S100B protein can be considered as a marker for blood brain barrier damage. The marker has an important role in the development and recovery of normal central nervous system (CNS) after injury. In addition to extra cerebral sources of S100B, the marker is principally built in the astroglial and Schwann cells. The neurobiochemical marker, S100B, has a pathognomonic role in the diagnosis of a broad spectrum of brain damage including traumatic brain injury (TBI), brain tumor, and stroke. Moreover, a potential predicting role for the neurobiochemical marker has been presumed in the efficiency of brain damage treatment and prognosis. However further animal and human studies are required before widespread routine clinical introduction of S100 protein.

Erythema Multiforme Associated With Misoprostol: A Case Report.

A 33-year-old healthy woman at 6 weeks of gestation without any underlying disease developed erythema multiforme (EM) after misoprostol. She had no history of herpes simplex virus infection and drug allergy to nonsteroidal anti-inflammatory drugs and antibiotic agents. Medical abortion was performed at 6 weeks' gestation. Later day, the patient developed oral lesions as several white bullae lesions in her buccal mucosa and hyperkeratotic lip plaques with mild pain. Then, lesions resolved within approximately 3 weeks. Microscopic finding of oral biopsy from beneath the tongue and lesions was performed. The result was consistent with erosive mucosa with granulation tissue formation and acute inflammation in favor of EM. This is the case report of probable misoprostol-induced EM. Because EM may produce in skin as a Stevens-Johnson syndrome in subsequent attack, monitoring of this adverse drug reaction should be considered for proper management and follow-up.

Oxidative stress in chronic kidney disease.

Patients with chronic kidney disease (CKD) have high incidence rates of cardiovascular disease and malignancy. Several factors contribute to these conditions. Structural characteristics in CKD, loss of renal energy, and uremia result in an imbalance between free radical production and antioxidant defenses. Also, CKD patients usually have multiple cardiovascular risk factors like diabetes mellitus, dyslipidemia, and hypertension. These conditions are associated with oxidative stress, which can trigger the inflammatory process and accelerate renal injury progression. There are some clinical biomarkers to detect oxidative stress and antioxidant status in CKD patients. Antioxidant therapies may be beneficial in reducing oxidative stress, lowering uremic cardiovascular toxicity, and improving survival. Therefore, their roles in CKD patients have been evaluated in several studies as a new target for therapeutic intervention. This review provides an overview of oxidative stress mechanisms, clinical squeals, biomarkers, and possible antioxidant therapies in CKD patients.

Effect of N-acetyl cysteine and vitamin C on kidney allograft function biomarkers interleukin-18 and neutrophil gelatinase-associated lipocalin.

INTRODUCTION: Delayed graft function (DGF) is a consequence of ischemia-reperfusion injuries in kidney allografts, for which no definite treatment is available. The neutrophil gelatinase-associated lipocalin (NGAL) and interleukin-18 (IL-18) are introduced as the most promising urine biomarkers to detect DGF. N-acetylcysteine (NAC) and vitamin C, well-known potent antioxidants that scavenge free radicals, may alleviate kidney injury. This study investigated the protective effects of NAC alone and in combination with vitamin C on DGF, by measuring IL-18 and NGAL in living donor kidney transplantations. MATERIALS AND METHODS: Patients transplanted between January 2011 and February 2013 were randomly divided into 3 groups to receive routine anti-rejection medication only (n = 32), NAC plus routine immunosuppressive regimen (NAC group; n = 33), and NAC and vitamin C plus routine regimen (NAC and vitamin C group; n = 19). Urine samples were taken 4 hours and 24 hours after transplantation. Enzyme-linked immunosorbent assay kits were utilized for measuring urine NGAL and IL-18. RESULTS: There were no significant differences in the DGF prevalence and its duration between the study arms. Although the levels of NGAL and IL-18 decreased in the NAC and NAC and vitamin C groups, these reductions were not significant. Glomerular filtration rate at 30 and 60 days after transplantation were not significantly different between study groups, either. CONCLUSIONS: Our results showed that NAC is a safe drug without significant adverse effects in kidney transplant recipients; however, its potential useful effects on urinary biomarkers of DGF were not illustrated in the present study.

Oxidative stress in kidney transplantation: causes, consequences, and potential treatment.

Oxidative stress is a major mediator of adverse outcomes throughout the course of transplantation. Transplanted kidneys are prone to oxidative stress-mediated injury by pre-transplant and post-transplant conditions that cause reperfusion injury or imbalance between oxidants and antioxidants. Besides adversely affecting the allograft, oxidative stress and its constant companion, inflammation, cause cardiovascular disease, cancer, metabolic syndrome, and other disorders in transplant recipients. Presence and severity of oxidative stress can be assessed by various biomarkers produced from interaction of reactive oxygen species with lipids, proteins, nucleic acids, nitric oxide, glutathione, etc. In addition, expression and activities of redox-sensitive molecules such as antioxidant enzymes can serve as biomarkers of oxidative stress. Via activation of nuclear factor kappa B, oxidative stress promotes inflammation which, in turn, amplifies oxidative stress through reactive oxygen species generation by activated immune cells. Therefore, inflammation markers are indirect indicators of oxidative stress. Many treatment options have been evaluated in studies conducted at different stages of transplantation in humans and animals. These studies have provided useful strategies for use in donors or in organ preservation solutions. However, strategies tested for use in post-transplant phase have been largely inconclusive and controversial. A number of therapeutic options have been exclusively examined in animal models and only a few have been tested in humans. Most of the clinical investigations have been of short duration and have provided no insight into their impact on the long-term survival of transplant patients. Effective treatment of oxidative stress in transplant population remains elusive and awaits future explorations.