MiR-3168, miR-6125, and miR-4718 as potential predictors of cisplatin-induced nephrotoxicity in patients with head and neck cancer

BACKGROUND: No biomarker is available for identifying cancer patients at risk of developing nephrotoxicity when treated with cisplatin. METHODS: We performed microRNA (miRNA) sequencing using plasma collected 5 days after cisplatin treatment (D5) from twelve patients with head and neck cancer with and without nephrotoxicity (grade ≥ 2 increased serum creatinine). The most differentially expressed miRNAs between the two groups were selected for quantification at baseline and D5 in a larger cohort of patients. The association between miRNAs and nephrotoxicity was evaluated by calculating the odds ratio (OR) from univariate logistic regression. Receiver operating characteristic curves (ROC) were used to estimate the area under the curve (AUC), sensitivity, and specificity. RESULTS: MiR-3168 (p = 1.98 × 10− 8 ), miR-4718 (p = 4.24 × 10− 5 ), and miR-6125 (p = 6.60 × 10− 5 ) were the most differentially expressed miRNAs and were further quantified in 43, 48, and 53 patients, respectively. The baseline expression of miR-3168 (p = 0.0456, OR = 1.03, 95% CI: 1.00­1.06) and miR-4718 (p = 0.0388, OR = 1.56, 95% CI: 1.03­ 2.46) were associated with an increased risk of nephrotoxicity, whereas miR-6125 showed a trend (p = 0.0618, OR = 1.73, 95% CI: 0.98­3.29). MiR-4718 showed the highest AUC (0.77, 95% CI: 0.61­0.93) with sensitivity of 66.76 and specificity of 79.49. CONCLUSIONS: We have provided evidence of baseline plasmatic expression of miR-3168, miR-6125, and miR-4718 as potential predictors of cisplatin-induced nephrotoxicity.

MiR-3168, miR-6125, and miR-4718 as potential predictors of cisplatin-induced nephrotoxicity in patients with head and neck cancer.

BACKGROUND: No biomarker is available for identifying cancer patients at risk of developing nephrotoxicity when treated with cisplatin. METHODS: We performed microRNA (miRNA) sequencing using plasma collected 5 days after cisplatin treatment (D5) from twelve patients with head and neck cancer with and without nephrotoxicity (grade ≥ 2 increased serum creatinine). The most differentially expressed miRNAs between the two groups were selected for quantification at baseline and D5 in a larger cohort of patients. The association between miRNAs and nephrotoxicity was evaluated by calculating the odds ratio (OR) from univariate logistic regression. Receiver operating characteristic curves (ROC) were used to estimate the area under the curve (AUC), sensitivity, and specificity. RESULTS: MiR-3168 (p = 1.98 × 10- 8), miR-4718 (p = 4.24 × 10- 5), and miR-6125 (p = 6.60 × 10- 5) were the most differentially expressed miRNAs and were further quantified in 43, 48, and 53 patients, respectively. The baseline expression of miR-3168 (p = 0.0456, OR = 1.03, 95% CI: 1.00-1.06) and miR-4718 (p = 0.0388, OR = 1.56, 95% CI: 1.03-2.46) were associated with an increased risk of nephrotoxicity, whereas miR-6125 showed a trend (p = 0.0618, OR = 1.73, 95% CI: 0.98-3.29). MiR-4718 showed the highest AUC (0.77, 95% CI: 0.61-0.93) with sensitivity of 66.76 and specificity of 79.49. CONCLUSIONS: We have provided evidence of baseline plasmatic expression of miR-3168, miR-6125, and miR-4718 as potential predictors of cisplatin-induced nephrotoxicity.

Polymyxin B clinical outcomes: A prospective study of patients undergoing intravenous treatment.

WHAT IS KNOWN AND OBJECTIVE: Polymyxins, especially polymyxin B, has become the last line of therapy against Gram-negative pathogens' carbapenemase producers. However, given increasing use of polymyxin B in clinical settings its therapeutic value has been evaluated worldwide due to its toxic effects. The aim of this study was to assess the efficacy and safety of antimicrobial therapy with polymyxin B in patients with multidrug-resistant bacteria in Brazil. METHODS: This was a prospective cohort study in a 403-bed academic tertiary care centre, located in the countryside of Brazil. Patients receiving polymyxin B intravenous treatment for at least 72 hours were eligible for the study. Antimicrobial susceptibility, adverse reactions and clinical outcomes were submitted for descriptive analysis. Main outcomes measure the following: Patients' conditions following treatment (Treatment Success, Mortality, Treatment Failure, Inadequate Empiric Treatment or Indeterminate Response) and toxicities induced by polymyxin B (nephrotoxicity and skin hyperpigmentation). RESULTS AND DISCUSSION: Among 247 patients, treatment success was achieved in 25.1%, while mortality was observed in 32.8%. Empirical therapy was prescribed for 26.3% of the patients. Nephrotoxicity was reported in 40.5%. The carbapenemase producer, Klebsiella pneumonia, was the bacterium most associated with mortality (22.2%). CONCLUSIONS: Even though polymyxin B is currently the main therapy against carbapenemase producers, its use demands robust criteria to lead to positive clinical outcomes.

Brazil's resolutions to regulate the sale of antibiotics: Impact on consumption and Escherichia coli resistance rates.

OBJECTIVE: The aim of this study was to determine the impact of two resolutions to restrict antibiotic use (RDCs no. 44/2010 and 20/2011) in the Campinas metropolitan area (Sao Paulo, Brazil) on antibiotic consumption, resistance rates, and trends in Escherichia coli-causing community-acquired urinary tract infection (UTI). METHODS: The annual retail sale information of antibiotics from drugstores in the Campinas metropolitan area between 2008 and 2012 were obtained through the Intercontinental Medical Statistics Health of Brazil. The daily-defined dose (DDD)/1000 inhabitants/day was calculated from these data to measure consumption. To examine resistance rates, we performed an observational retrospective study in a Campinas teaching hospital, where urinary cultures from outpatients with a clinical suspicion of UTI between October 2009 and September 2015 were analyzed. RESULTS: We observed an increase in rates of antibiotic sales from 2008 to 2011 (cephalosporin: 216.8%, quinolones: 170.9%, aminopenicillins: 140.9%), followed by a decrease in sales in 2012 (cephalosporin: 19.4%, quinolones: 12.7%, aminopenicillins: 11.1%). Sale of nitrofurans, however, did not significantly change during this period. In the retrospective analysis, we observed a significant increasing trend of E. coli resistance for all antibiotic classes, except nitrofurans and folate pathway inhibitors. CONCLUSIONS: We found changes in antibiotic consumption, with an initial increase, followed by a decrease in sales after implementation of the resolutions. However, bacterial resistance does not appear to be affected by the RDCs.

Non-multidrug-resistant, methicillin-resistant Staphylococcus aureus in a neonatal unit.

BACKGROUND: In the last decade, non-multiresistant methicillin-resistant Staphylococcus aureus (NM-MRSA) has been described as an important agent in bloodstream infections in our hospital. METHODS: This prospective cohort study, conducted from February 2009 through January 2010 in the neonatal unit, evaluated 403 newborns (NB), their 382 mothers and 148 health care workers (HCW). RESULTS: Approximately 217 NB (54%), 187 mothers (48%) and 87 HCW (59%) were colonized by S. aureus (SA). MRSA colonization was greater among NB (15%) than mothers (4.7%) and HCW (3.4%). Although mother-to-NB transmission occurred, in most cases mothers were not responsible for NB colonization. There were 2 predominant PFGE patterns among the NB and some mothers and HCW became colonized by them. Factors significantly associated with MRSA carriage by NB were lower level of maternal schooling (risk factor: odds ratio: 2.99; 95% confidence interval: 1.10-8.07) and maternal rhinosinusitis (protective factor: odds ratio: 0.33; 95% confidence interval:0.12-0.88). Among NB who remained hospitalized for more than 72 hours, breast feeding was protective (odds ratio: 0.22; 95% confidence interval: 0.05-0.98). All the isolates were NM-MRSA, carried few virulence factors and SCCmec types IVa and type IVd predominated. CONCLUSIONS: Although there were no cases of infection, nosocomial transmission of MRSA clearly occurred in the neonatal unit, and this highlights the need for infection control practices such as hand hygiene to prevent cross-dissemination. Other healthcare practices, which are very basic but also ample in scope, may play a role, such as general education of women and breast feeding.

Performance of surveillance cultures at different body sites to identify asymptomatic Staphylococcus aureus carriers.

The objective was to evaluate the performance of surveillance cultures at various body sites for Staphylococcus aureus colonization in pregnant women and newborns (NB) and the factors associated with nasal colonization. For NB, 4 sites were evaluated: nares, oropharynx, perineum, and umbilical stump (birth, third day, and weekly). For pregnant women, 4 sites during labor: anterior nares, anus, perineum, and oropharynx. Nasally colonized patients were compared with colonized only extranasally. Colonization was 53% of 392 pregnant women (methicillin-resistant S. aureus [MRSA]: 4%) and 47% of 382 NB (MRSA: 9%). For newborn patients, the best body site was the umbilical stump (methicillin-susceptible S. aureus [MSSA]: 64%; MRSA: 68%) and the combination of nares + umbilical (MSSA: 86%; MRSA: 91%). Among pregnant women, the best body site was the anterior nares (MSSA: 59%; MRSA: 67%) and the combination of nares + oropharynx (MSSA: 83%; MRSA: 80%). A smaller number of household members were associated with MRSA carriage in pregnant women (2.2 ± 0.6 versus 3.6 ± 1.8; P = 0.04). In conclusion, multiple culture sites are needed. Control programs based on surveillance cultures may be compromised.