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.
Three point mutations (A2143G, A2142G, and A2142C) have been involved in Helicobacter pylori clarithromycin resistance. To compare the eradication rates among the different point mutations and the efficacy of triple therapy and a sequential regimen according to genotypic resistance. Post hoc subgroup study from a multicenter, randomized trial. Two hospitals in central and southern Italy between January and December 2001. 156 patients with H. pylori infection. Real-time polymerase chain reaction for assessing clarithromycin resistance; histology, rapid urease test, and 13C-urea breath test at entry and after 4 to 6 weeks. 7-day triple therapy (20 mg of rabeprazole, 500 mg of clarithromycin, and 1 g of amoxicillin) in 75 patients or a 10-day sequential regimen (20 mg of rabeprazole plus 1 g of amoxicillin for 5 days and 20 mg of rabeprazole, 500 mg of clarithromycin, and 500 mg of tinidazole for the remaining 5 days) in 81 patients. All drugs were given twice daily. Helicobacter pylori infection was eradicated in 11 of 23 patients (48%) with the A2143G mutation and in 14 of 15 patients (93%) with either A2142G or A2142C strains (difference, 45 percentage points [95% CI, 15 to 65 percentage points]; P = 0.004). The sequential regimen achieved a higher cure rate than triple therapy in A2143G mutate strains (difference, 49 percentage points [CI, 8 to 72 percentage points]; P = 0.024). The post hoc substudy design may require further confirmation. Other limitations are the accessibility to the tool and the cost of investigations (€70 per patient). The A2143G mutation seemed to be associated with a very low eradication rate. The sequential regimen achieved a higher cure rate than standard therapy even in patients with these strains.
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.
1 November 2009 in Foodborne Pathogens and Disease
Two cases of gastric anisakiasis have been documented in two Italian women who had consumed raw anchovies ( Engraulis encrasicolus ). The first patient was a 49-year-old woman presenting with epigastric pain and bloody vomiting after ingestion of marinated (vinegar) raw anchovies. During the esophagogastroduodenoscopy (EGDS) a white color worm was detected and extracted from cardia by means of biopsy forceps. The second patient was a 59-year-old woman with irritable bowel syndrome and gastritis, who underwent to periodical EGDSs. In the course of the last EGDS, a white color round worm on antrum and a small polyp on the fundus of the stomach were observed. The two nematodes have been identified as L3 larvae of the genus Anisakis by a light microscope, and as Anisakis pegreffi by polymerase chain reaction–restriction fragment length polymorphism. The molecular identification of the etiological agent at the species level allows to identify what Anisakidae species play a zoonotic role and which are the fish host species.
1 August 2013 in International Journal of Antimicrobial Agents
The risk to public health from the large number of dog stools present on streets of urban areas is cause for concern. Dog faeces may be a serious hazard because they may contain microorganisms that are both pathogenic to humans and resistant to several classes of antibiotics. The aim of this study was to evaluate the potential for zoonotic infections and for the presence of antibiotic resistant bacteria in canine faeces which contaminates the urban environment. A total of 418 canine faecal samples were collected from streets in seven areas of Bari, Southern Italy. We have isolated multi-drug resistant Enterococci and meticillin-resistant Staphylococcus aureus from these dog faecal samples. The presence of the resistant bacteria in an urban environment may represent a public health hazard which requires control measures by competent authorities. No Salmonella, Yersinia or Campylobacter species were isolated. Giardia cysts were detected in 1.9% of the samples. The predominant Enterococcus species were E.faecium (61.6%), E. gallinarum (23.3%) and E. casseliflavus (5.5%). Other species, including E. faecalis were also isolated. These strains were resistant to clindamycin (86.3%), tetracycline (65.7%), erythromycin (60.27%) and ampicillin (47.9%). High-level aminoglycoside resistance (HLAR) was found in 65.7% of enterococci. Resistance to three or more antibiotics and six or more antibiotics were observed in 67.12% and 38.4% of Enterococcus spp., respectively. Resistance to vancomycin and teicoplanin was not detected in any of the Enterococcus spp. isolated. Methicillin-resistant Staphylococcus aureus was isolated in 0.7% of the faecal samples. Canine faeces left on the streets may represent a risk factor for transmission of microorganisms and a reservoir of multidrug- resistant bacteria thus contributing to the spread of resistance genes into an urban area.