Effect of early antibiotic prophylaxis with ertapenem and meropenem in experimental acute pancreatitis in rats

Mechanistic Insights Into the Differential Efficacy of Daptomycin Plus β-Lactam Combinations Against Daptomycin-Resistant Enterococcus faecium

BACKGROUND

The combination of daptomycin (DAP) plus ampicillin (AMP), ertapenem (ERT), or ceftaroline has been demonstrated to be efficacious against a DAP-tolerant Enterococcus faecium strain (HOU503). However, the mechanism for the efficacy of these combinations against DAP-resistant (DAP-R) E. faecium strains is unknown.

METHODS

We investigated the efficacy of DAP in combination with AMP, ERT, ceftaroline, ceftriaxone, or amoxicillin against DAP-R E. faecium R497 using established in vitro and in vivo models. We evaluated pbp expression, levels of penicillin-binding protein (PBP) 5 (PBP5) and β-lactam binding affinity in HOU503 versus R497.

RESULTS

DAP plus AMP was the only efficacious regimen against DAP-R R497 and prevented emergence of resistance. DAP at 8, 6, and 4 mg/kg in combination with AMP was efficacious but showed delayed killing compared with 10 mg/kg. PBP5 of HOU503 exhibited amino acid substitutions in the penicillin-binding domain relative to R497. No difference in pbp mRNA or PBP5 levels was detected between HOU503 and R497. labeling of PBPs with Bocillin FL, a fluorescent penicillin derivative, showed increased β-lactam binding affinity of PBP5 of HOU503 compared with that of R497.

CONCLUSIONS

Only DAP (10 mg/kg) plus AMP or amoxicillin was efficacious against a DAP-R E. faecium strain, and pbp5 alleles may be important contributors to efficacy of DAP plus β-lactam therapy.

Antibiotic-Induced Pathobiont Dissemination Accelerates Mortality in Severe Experimental Pancreatitis

Although antibiotic-induced dysbiosis has been demonstrated to exacerbate intestinal inflammation, it has been suggested that antibiotic prophylaxis may be beneficial in certain clinical conditions such as acute pancreatitis (AP). However, whether broad-spectrum antibiotics, such as meropenem, influence the dissemination of multidrug-resistant (MDR) bacteria during severe AP has not been addressed. In the currently study, a mouse model of obstructive severe AP was employed to investigate the effects of pretreatment with meropenem on bacteria spreading and disease outcome. As expected, animals subjected to biliopancreatic duct obstruction developed severe AP. Surprisingly, pretreatment with meropenem accelerated the mortality of AP mice (survival median of 2 days) when compared to saline-pretreated AP mice (survival median of 7 days). Early mortality was associated with the translocation of MDR strains, mainly Enterococcus gallinarum into the blood stream. Induction of AP in mice with guts that were enriched with E. gallinarum recapitulated the increased mortality rate observed in the meropenem-pretreated AP mice. Furthermore, naïve mice challenged with a mouse or a clinical strain of E. gallinarum succumbed to infection through a mechanism involving toll-like receptor-2. These results confirm that broad-spectrum antibiotics may lead to indirect detrimental effects during inflammatory disease and reveal an intestinal pathobiont that is associated with the meropenem pretreatment during obstructive AP in mice.

Perioperative antimicrobial therapy in preventing infectious complications following pancreatoduodenectomy

BACKGROUND & OBJECTIVES

Infectious complications have been reported to occur in up to 45 per cent of patients, following pancreatoduodenectomy (PD). The incidence of perioperative infectious and overall complications is higher in patients undergoing preoperative invasive endoscopic procedures. The aim of the study was to compare the role of a carbapenem administered as three-once daily perioperative doses on infectious complications in patients at high risk for these complications versus those at low risk.

METHODS

A retrospective study with some secondary data collected from records was carried out on the data from a prospectively maintained surgical database of patients undergoing PD for pancreatic and periampullary lesions at a tertiary referral care centre, between June 2011 and May 2013. Patients were divided into two groups for comparison based on whether they underwent at least one preoperative endoscopic interventional procedure before PD (high-risk - intervention and low-risk - no intervention). All patients were administered three-once daily doses of ertapenem (1 g).

RESULTS

A total of 135 patients in two groups were comparable in terms of demographic and nutritional, surgical and histopathological factors. No significant difference between the two groups in terms of the overall morbidity (38.7 vs 35.7%), infectious complications (9.7 vs 4.8%), mortality (2.2 vs 2.4%) and mean post-operative hospital stay (9.2 vs 8.9 days) was observed.

INTERPRETATION & CONCLUSIONS

Perioperative three-day course of once-daily administered ertapenem resulted in a non-significant difference in infectious and overall complications in high-risk patients undergoing PD as compared to the low-risk group.