Fatal Clostridium septicum gas gangrene complicating ECMO: case report and review of literature.

Clostridium septicum gas gangrene is a severe and deadly infection caused by an anaerobic, spore-forming, Gram-positive bacillus. As previously described, two entities are observed: traumatic and spontaneous (or non-traumatic) forms. In this report, we aim to describe the case of a fulminant and ultimately fatal C. septicum myonecrosis occurring in a patient who was first admitted for refractory cardiac arrest and placed on veino-arterial extracorporeal membrane oxygenation (ECMO). Building upon prior studies that have documented cases of spontaneous gas gangrene caused by C. septicum, we provide an updated compilation, focusing on microbiological characteristics of C. septicum, along with the diagnostic and therapeutic challenges associated with spontaneous gas gangrene. Additionally, the specific clinical situation of our case illustrates the seriousness of this infectious complication that combined both spontaneous and traumatic gas gangrene risk factors. We thus, discuss the antibiotic coverage prior to the initiation of ECMO procedure.

Effectiveness of water system chemical disinfection against Pseudomonas aeruginosa infections, despite a not-so-obvious connection.

BACKGROUND: Pseudomonas aeruginosa is a well-recognized opportunistic pathogen frequently responsible for hospital-acquired infections. Acquisition routes of P aeruginosa are both endogenous and exogenous, including transmission from a portion of the hospital water system. METHODS: The impact of disinfection procedures of the water system and description routes of P aeruginosa transmission in a surgical intensive care unit over a 2-year period were investigated. Two distinct periods A and B were considered, respectively, before and after the disinfection. Fourier transform infrared spectroscopy was used to compare isolates recovered from patients and tap water. RESULTS: Overall, 21.3% of tap water samples were positive but with a significantly lower rate in period B. Concomitantly, the prevalence of patients positive for P aeruginosa decreased from 2.6% to 1%, suggesting a correlation between the presence of environmental sources and patient contaminations. The results revealed that 18% of patients were involved in cross-transmission events not related to any isolate recovered from water, suggesting transmission through care practices. Conversely, only 1 environmental transmission event was suspected in a patient. CONCLUSIONS: Although the link between the hospital environment and patients was unclear, HCW-associated care practices could be related to contaminated point-of-use waters and then indirect spreading to patients.

Updated Review on Clinically-Relevant Properties of Delafloxacin.

The extensive use of fluoroquinolones has been consequently accompanied by the emergence of bacterial resistance, which triggers the necessity to discover new compounds. Delafloxacin is a brand-new anionic non-zwitterionic fluoroquinolone with some structural particularities that give it attractive proprieties: high activity under acidic conditions, greater in vitro activity against Gram-positive bacteria-even those showing resistance to currently-used fluoroquinolones-and nearly equivalent affinity for both type-II topoisomerases (i.e., DNA gyrase and topoisomerase IV). During phases II and III clinical trials, delafloxacin showed non-inferiority compared to standard-of-care therapy in the treatment of acute bacterial skin and skin structure infections and community-acquired bacterial pneumonia, which resulted in its approval in 2017 by the Food and Drug Administration for indications. Thanks to its overall good tolerance, its broad-spectrum in vitro activity, and its ease of use, it could represent a promising molecule for the treatment of bacterial infections.

Early detection of plasma d-lactate: Toward a new highly-specific biomarker of bacteraemia?

Background: Bloodstream infections are a leading cause of mortality. Their detection relies on blood cultures (BCs) but time to positivity is often between tens of hours and days. d-lactate is a metabolite widely produced by bacteria but very few in human. We aimed to evaluate d-lactate, d-lactate/l-lactate ratio and d-lactate/total lactate ratio in plasma as potential early biomarkers of bacteraemia on a strictly biological standpoint. Methods: A total of 228 plasma specimens were collected from patients who had confirmed bacteraemia (n = 131) and healthy outpatients (n = 97). Specific l-lactate and d-lactate analyses were performed using enzymatic assays and analytical performances of d-lactate, d-lactate/total lactate and d-lactate/l-lactate ratios for the diagnosis of bacteraemia were assessed. Results: A preliminary in vitro study confirmed that all strains of Escherichia coli, Klebsiella pneumoniae and Staphylococcus aureus were able to produce d-lactate at significant levels. In patients, plasma d-lactate level was the most specific biomarker predicting a bacteraemia profile with a specificity and predictive positive value of 100% using a cut-off of 131 µmol.L-1. However, sensitivity and negative predictive value were rather low, estimated at 31% and 52%, respectively. d-lactate displayed an Area Under Receiver Operating Characteristic (AUROC) curve of 0.696 with a P value < 0.0001. There was no difference of d-lactate levels between BCs bottles positive for Gram-positive or Gram-negative bacteria (p = 0.55). Conclusion: d-lactate shows promise as a specific early biomarker of bacterial metabolism. The development of rapid automated assays could raise clinical applications for infectious diseases diagnosis including early bacteraemia prediction.