The Impact of Bile Duct Cultures on Surgical Site Infections in Pancreatic Surgery

Role of rectal colonization by third-generation cephalosporin-resistant Enterobacterales on the risk of surgical site infection after hepato-pancreato-biliary surgery

The impact of third-generation cephalosporin-resistant Enterobacterales (3GCR-E) rectal colonization in the development of subsequent infection after surgery is controversial. In particular, there is a lack of data in the context of hepato-pancreato-biliary (HPB) surgery. The objective of this study was to assess the prevalence of 3GCR-E intestinal carriage among patients undergoing elective HPB resection surgery and its impact on the incidence and etiology of surgical site infections (SSIs). This retrospective cohort study (January 2016-December 2022) was performed at Valme University Hospital (Seville, Spain). The inclusion criteria included (i) 18 years of age or older, (ii) undergoing elective HPB resection surgery, and (iii) availability of a periprocedural surveillance rectal swab culture to detect 3GCR-E. The prevalence of 3GCR-E intestinal carriage at elective HPB resection surgery was assessed, as well as SSI incidence at 30 days and possible associated factors. Two hundred nine patients were included. Eleven (5.3%) patients were colonized by 3GCR-E at baseline. According to 3GCR-E carriage status, 6 (55%) of the carriers developed SSI, whereas this occurred in 50 (25%) of non-carriers (P = 0.033). Likewise, the rates of SSI caused specifically by 3GCR-E were 83% (5 of 6) in 3GCR-E carriers and 6% (3 of 50) in non-carriers (P < 0.001). After multivariate analyses, 3GCR-E colonization at the time of surgery was identified as an independent predictor for developing SSI (adjusted odds ratio 4.63, 95% confidence interval: 1.177-18.232, P = 0.028). Despite a low prevalence of 3GCR-E intestinal carriage at surgery, 3GCR-E rectal colonization is associated with a higher risk of SSI among patients undergoing elective HPB resection surgery, with most SSIs being caused by the colonizing bacteria.

IMPORTANCE

In this Spanish retrospective cohort study, previous 3GCR-E rectal colonization was associated with a higher risk of SSI after hepato-pancreato-biliary resection surgeries. Most of SSIs were caused by the colonizing bacteria, suggesting a rationale for adapted perioperative antibiotic prophylaxis in known 3GCR-E colonized patients.

Need for a targeted perioperative antibiotic treatment protocol for patients with preoperative biliary drainage undergoing pancreaticoduodenectomy

PURPOSE

To evaluate the bacterobilia in patients undergoing pancreaticoduodenectomy (PD) based on whether they carry a preoperative biliary drainage or not and to analyse if a targeted perioperative antibiotic treatment based on the expected microbiology leads in no differences in Surgical Site Infections (SSI) between the groups.

METHODS

Retrospective observational single-center study of patients undergoing pancreaticoduodenectomy with preoperative biliary stent (group P, Prosthesis) and without stent (group NP, No Prosthesis). Postoperative complications including SSI and its subtypes were analyzed after applying a targeted perioperative antibiotic treatment protocol with cefotaxime and metronidazole (group NP) and piperacillin-tazobactam (group P).

RESULTS

Between January 2014 and December 2021, 127 patients were treated (84 in group NP and 43 in group P). Intraoperative cultures were positive in 16.7% (group NP) vs 76.7% (group P, p < 0.01). Microorganisms isolated in group NP included Enterobacterales (10.7%) and Enterococcus spp. (7.1%) with no Candida detected. In group P: Enterobacterales (51.2%), Enterococcus spp. (48.8%), and Candida (16.3%) were higher (p < 0.01%). No differences in morbidity and mortality were observed between the groups. SSI rate was 17.8% in group NP and 23.2% in group P (ns).

CONCLUSION

Bacterobilia differs in patients with biliary drainage, showing a higher presence of Enterobacterales, Enterococcus spp., and Candida. There were no differences in SSI incidence after applying perioperative antibiotic treatment tailored to the expected microorganisms in each group. This raises the need to reconsider conventional surgical prophylaxis in patients with biliary stent.

Relationship between Intraoperative Bile Culture Outcomes and Subsequent Postoperative Infectious Complications: A Retrospective Cohort Study

The presence of positive bile culture during intraoperative procedures has been associated with elevated morbidity and mortality rates in hepatobiliopancreatic surgeries, contributing to increased healthcare expenditures. However, the precise impact of bactobilia on the development of postoperative complications remains uncertain due to existing disparities in the published literature. In this retrospective cohort study, we assessed 137 patients who underwent major hepatobiliopancreatic surgery to examine the relationship between intraoperative bile culture outcomes and subsequent postoperative infectious complications. Among patients with bactobilia, a significant 35.1% exhibited systemic or local infectious complications, whereas only 11.1% of those with negative culture results experienced any infectious complications (p = 0.002). Similarly, a notable difference was observed in the incidence of surgical site infections, with 24.3% in the bactobilia group compared to 7.9% in the negative culture group (p = 0.01). A total of 74 monomicrobial cultures with microbiological growth were isolated, predominantly featuring Gram-negative microorganisms, primarily Enterobacteriaceae in 49 cultures. Escherichia coli was identified in 37.8% of positive cultures, while Klebsiella pneumoniae was evident in 21.6%. Gram-positive microorganisms were present in 10 cultures, with Enterococcus emerging as the prevailing species. The logistic regression model identified a positive bile culture as an independent factor significantly associated with infection development (OR: 2.26; 95% confidence interval: 1.23-11; p = 0.02). Considering the limitations of the study, these findings underscore the critical importance of conducting bile cultures during the intraoperative phase to enable vigilant monitoring and prompt management of infectious complications.

Prolonged antibiotics after pancreatoduodenectomy reduce abdominal infections in patients with positive bile cultures: a dual-center cohort study

BACKGROUND

Abdominal infections account for substantial morbidity after pancreatoduodenectomy. Contaminated bile is the presumed main risk factor, and prolonged antibiotic prophylaxis might prevent these complications. This study compared organ/space infection (OSIs) rates in patients receiving perioperative versus prolonged antibiotic prophylaxis after pancreatoduodenectomy.

METHODS

Patients undergoing pancreatoduodenectomy in two Dutch centers between 2016 and 2019 were included. Perioperative prophylaxis was compared prolonged prophylaxis (cefuroxime and metronidazole for five days). The primary outcome was an isolated OSI: an abdominal infection without concurrent anastomotic leakage. Odds ratios (OR) were adjusted for surgical approach and pancreatic duct diameter.

RESULTS

OSIs occurred in 137 out of 362 patients (37.8%): 93 patients with perioperative and 44 patients with prolonged prophylaxis (42.5% versus 30.8%, P = 0.025). Isolated OSIs occurred in 38 patients (10.5%): 28 patients with perioperative and 10 patients with prolonged prophylaxis (12.8% versus 7.0%, P = 0.079). Bile cultures were obtained in 198 patients (54.7%). Patients with positive bile cultures showed higher isolated OSI rates with perioperative compared to prolonged prophylaxis (18.2% versus 6.6%, OR 5.7, 95% CI: 1.3-23.9).

CONCLUSION

Prolonged antibiotics after pancreatoduodenectomy are associated with fewer isolated OSIs in patients with contaminated bile and warrant confirmation in a randomised controlled trial (Clinicaltrials.gov NCT0578431).

Broad vs Narrow Spectrum Antibiotics in Common Bile Duct Stones: A Post Hoc Analysis of an Eastern Association for the Surgery of Trauma Multicenter Study

BACKGROUND

Antimicrobial guidance for common bile duct stones during the perioperative period is limited. We sought to examine the effect of broad-spectrum (BS) vs narrow-spectrum (NS) antibiotics on surgical site infections (SSIs) in patients with common bile duct stones undergoing same-admission cholecystectomy.

STUDY DESIGN

We performed a post hoc analysis of a prospective, observational, multicenter study of patients undergoing same-admission cholecystectomy for choledocholithiasis and/or acute biliary pancreatitis between 2016 and 2019. We excluded patients with cholangitis, perforated cholecystitis, and nonbiliary infections on admission. Patients were divided based on receipt of BS or NS antibiotics. Our primary outcome was the incidence of SSIs, and secondary outcomes included hospital length of stay, acute kidney injury (AKI), and 30-day readmission for SSI.

RESULTS

The cohort had 891 patients: 51.7% (n= 461) received BS antibiotics and 48.3% (n = 430) received NS antibiotics. Overall antibiotic duration was longer in the BS group than in the NS group (6 vs 4 d, p = 0.01); however, there was no difference in rates of SSI (0.9% vs 0.5%, p = 0.7) or 30-day readmission for SSI (1.1% vs 1.2%, p = 1.0). Hospital length of stay was significantly longer in the BS group (p < 0.001) as were rates of AKI (5% vs 1.4%, p = 0.001). On multivariable regression, BS antibiotic use was a risk factor for AKI (adjusted odds ratio 2.8, 95% CI 1.16 to 7.82, p = 0.02).

CONCLUSION

The incidence of SSI and 30-day readmission for SSI was similar between antibiotic groups. However, BS antibiotic use was associated with a longer hospitalization and greater likelihood of AKI.

Intraoperative gram staining of bile for the prevention of infectious complications in pancreaticoduodenectomy

INTRODUCTION

Infectious complications play a prominent role in pancreaticoduodenectomy. Their incidence increases in cases with preoperative biliary drainage (PBD), due to the higher risk of bacterobilia. The aim of this study is to evaluate an antibiotherapy protocol based on intraoperative gram staining of bile and its impact on postoperative infectious complications.

METHODS

A retrospective study analysing the incidence of infectious complications between two groups of 25 consecutive patients undergoing pancreaticoduodenectomy. In group 1, cefazolin prophylaxis was administered to patients without PBD. In cases with PBD a five days antibiotherapy with piperacillin-tazobactam was administered. In group 2, intraoperative gram staining of bile was routinely performed. If no microorganisms were detected, antibiotherapy was limited to cefazolin prophylaxis. If bacterobilia was detected, targeted antibiotherapy was administered for five days.

RESULTS

The incidence of sepsis and organ/space infection in group 2 was 4% compared to 32% and 24% in group 1 respectively (p < 0.05). No differences were observed in the remaining morbimortality variables. The most prevalent microorganisms in bile were Enterococcus spp. and Klebsiella spp. In postoperative samples, they only appeared in 4% of cases in group 2 (p < 0.05), in favour of S. epidermidis, although they were also prevalent in group 1 (28 and 24% respectively).

CONCLUSION

Intraoperative gram staining of bile fluid could be a useful tool to conduct personalised antibiotic therapy in pancreaticoduodenectomy and contribute to the control of infectious complications.

The clinical impact of preoperative biliary drainage on isolated infectious complications (iiC) after pancreatic head resection—a retrospective study

Background

The perioperative morbidity after pancreatoduodenectomy (PD) is mostly influenced by intraabdominal complications which are often associated with infections. In patients with preoperative biliary drainage (PBD), the risk for postoperative infections may be even elevated. The aim of this study is to explore if isolated infectious complications without intraabdominal focus (iiC) can be observed after PD and if they are associated to PBD and antibiotic prophylaxis with potential conclusions for their treatment.

Methods

During a 10-year period from 2009 to 2019, all consecutive PD were enrolled prospectively in a database and analyzed retrospectively. Bacteriobilia (BB) and Fungibilia (FB) were examined by intraoperatively acquired smears. A perioperative antibiotic prophylaxis was performed by Ampicillin/Sulbactam. For this study, iiC were defined as postoperative infections like surgical site infection (SSI), pneumonia, unknown origin etc. Statistics were performed by Fisher’s exact test and Mann Whitney U test.

Results

A total of 426 PD were performed at the Vivantes Humboldt-hospital. The morbidity was 56% (n = 238). iiC occurred in 93 patients (22%) and accounted for 38% in the subgroup of patients with postoperative complications. They were not significantly related to BB and PBD but to FB. The subgroup of SSI, however, had a significant relationship to BB and FB with a poly microbial profile and an accumulation of E. faecalis, E. faecium, Enterobacter, and Candida. BB was significantly more frequent in longer lay of PBD. Resistance to standard PAP and co-existing resistance to broad spectrum antibiotics is frequently found in patients with iiC. The clinical severity of iiC was mostly low and non-invasive therapy was adequate. Their treatment led to a significant prolongation of the hospital stay.

Conclusions

iiC are a frequent problem after PD, but only in SSI a significant association to BB and FB can be found in our data. Therefore, the higher resistance of the bacterial species to routine PAP, does not justify broad spectrum prophylaxis. However, the identification of high-risk patients with BB and PBD (length of lay) is recommended. In case of postoperative infections, an early application of broad-spectrum antibiotics and adaption to microbiological findings from intraoperatively smears may be advantageous.

Antibiotic-Resistant Bacteria Colonizing the Bile Duct Are Associated with Increased Morbidity and Mortality after Resection of Extrahepatic Cholangiocarcinoma

Background: Patients with extrahepatic cholangiocarcinoma (CCA) face considerable morbidity including septic complications after surgery. The aim of this study was to characterize the bacterial spectrum of the common hepatic duct (CHD) and its clinical relevance regarding morbidity and mortality after resection of extrahepatic CCA. Methods: We retrospectively analyzed data from 205 patients undergoing surgery for extrahepatic CCA in our department between January 2000 and March 2015. Patients were reviewed for pre-operative medical conditions, biliary bacterial flora obtained from intra-operative swabs, different septic complications, and post-operative outcome. Results: Bacterial colonization of the CHD was observed in 84.9% of the patients, with Enterococcus faecalis being detected most frequently (28.3%). Wound infections occurred in 30.7% of patients. Bacterial flora of the CHD and of the post-operatively colonized wounds coincided in 51.5% and of intra-abdominal swabs obtained during surgical revisions in 40.0%. Ciprofloxacin-resistant bacteria in the CHD were identified as independent risk factor for wound infections (odds ratio [OR], 3.330; 95% confidence interval [CI], 1.771-6.263; p < 0.001) and for complications requiring surgical revision (OR, 2.417; 95% CI, 1.288-4.539; p = 0.006). Most important independent risk factors for intra-hospital mortality were ampicillin-sulbactam-resistant bacteria in the CHD (OR, 3.969; 95% CI, 1.515-10.399; p = 0.005) and American Society of Anesthesiologists (ASA) grading >2 (OR, 2.936; 95% CI, 1.337-6.451; p = 0.007). Conclusions: Antibiotic-resistant bacteria from the CHD are associated with increased morbidity and mortality in patients undergoing resection for extrahepatic CCA.

The Role of Targeted Versus Standard Antibiotic Prophylaxis in Pancreatoduodenectomy in Reducing Postoperative Infectious Complications: A Systematic Review and Meta-analysis

INTRODUCTION

Infectious complications are common after pancreatoduodenectomy, which in turn are associated with preoperative biliary drainage. Current guidelines recommend a first-generation cephalosporin as perioperative antibiotic prophylaxis. However, some studies support the use of targeted antibiotics. The aim of this systematic review and meta-analysis is to evaluate the role of prophylactic targeted antibiotics compared to standard antibiotics in reducing postoperative infections after pancreatoduodenectomy.

METHODS

A search from MEDLINE, EMBASE, and Cochrane library from 1946 to July 2020 was conducted. Studies were included if they compared targeted antibiotics with standard perioperative antibiotics while including outcome data on surgical site infections (SSI). Targeted therapy was defined as perioperative antibiotics targeting organisms prevalent in bile instrumentation or by culture data obtained from the patient or institution. Outcomes assessed were the rate of SSIs and their microbiology profile. Analyses included demographic data, perioperative antibiotics, postoperative outcomes including microbiology data, and meta-analysis was performed where applicable.

RESULTS

Seven studies were included, with a total of 849 patients undergoing pancreatoduodenectomy. Targeted antibiotics were associated with a significantly lower rate of postoperative SSI compared to standard antibiotic therapy [21.1% vs 41.9%; risk ratios (RR) 0.55, 95% confidence interval 0.37-0.81]. Wound/incisional site infections and organ space infections were lower in patients receiving targeted antibiotic prophylaxis (RR 0.33, P = 0.0002 and RR 0.54, P = 0.0004, respectively). Enterococcus species were the most common bacteria reported.

CONCLUSION

There was a significant reduction in overall SSI rates when targeted antibiotics was used. Current standard antibiotic prophylaxis is inadequate in covering microbes prevalent in postoperative infections developing after pancreatoduodenectomy.

"Answers in hours": A prospective clinical study using nanopore sequencing for bile duct cultures

BACKGROUND

Surgical site infection is a major source of morbidity in patients undergoing pancreatic head resection and is often from organisms in intraoperative bile duct cultures. As such, many institutions use prolonged prophylactic antibiotics and tailor based on bile duct cultures. However, standard cultures take days, leaving many patients unnecessarily on prolonged antibiotics. Nanopore sequencing can provide data in hours and, thus, has the potential to improve antibiotic stewardship. The present study investigates the feasibility of nanopore sequencing in intraoperative bile samples.

METHODS

Patients undergoing pancreatic head resection were included. Intra-operative bile microbial profiles were determined with standard cultures and nanopore sequencing. Antibiotic recommendations were generated, and time-to-results determined for both methods. Organism yields, resistance patterns, antibiotic recommendations, and costs were compared.

RESULTS

Out of 42 patients, 22 (52%) had samples resulting in positive standard cultures. All positive standard cultures had microbes detected using nanopore sequencing. All 20 patients with negative standard cultures had negative nanopore sequencing. Nanopore sequencing detected more bacterial species compared to standard cultures (10.5 vs 4.4, p < 0.05) and more resistance genotypes (10.3 vs 2.7, p < 0.05). Antimicrobial recommendations based on nanopore sequencing provided coverage for standard cultures in 27 out of 44 (61%) samples, with broader coverage recommended by nanopore sequencing in 13 out of 27 (48%) of these samples. Nanopore sequencing results were faster (8 vs 98 hours) than standard cultures but had higher associated costs ($165 vs $38.49).

CONCLUSION

Rapid microbial profiling with nanopore sequencing is feasible with broader organism and resistance profiling compared to standard cultures. Nanopore sequencing has perfect negative predictive value and can potentially improve antibiotic stewardship; thus, a randomized control trial is under development.

Clinical implications of bile cultures obtained during pancreatoduodenectomy: a cohort study and meta-analysis

BACKGROUND

The association between intraoperative bile cultures and infectious complications after pancreatoduodenectomy remains unclear. This cohort study and meta-analysis aimed to determine the predictive role of intraoperative bile cultures in abdominal infectious complications after pancreatoduodenectomy.

METHODS

The cohort study included 114 patients undergoing pancreatoduodenectomy. Regression analyses were used to estimate the odds to develop an organ space infection (OSI) or isolated OSI (OSIs without a simultaneous complication potentially contaminating the intraabdominal space) after a positive bile culture. A systematic review and meta-analysis was performed on abdominal infectious complications (Mantel-Haenszel fixed-effect model).

RESULTS

The positive bile culture rate was 61%, predominantly in patients after preoperative biliary drainage (98% vs 26%, p < 0.001). OSIs occurred in 35 patients (31%) and isolated OSIs in nine patients (8%) and were not associated with positive bile cultures (OSIs: odds ratio = 0.6, 95% CI = 0.25-1.23, isolated OSIs: odds ratio = 0.77, 95% CI = 0.20-3.04). In the meta-analysis, 15 studies reporting on 2047 patients showed no association between positive bile cultures and abdominal infectious complications (pooled odds ratio = 1.3, 95% CI = 0.98-1.65).

CONCLUSION

Given the rare occurrence of isolated OSIs and similar odds for patients with positive and negative bile cultures to develop abdominal infectious complications, routine performance of bile cultures should be reconsidered.

Intraoperative gram staining of bile for the prevention of infectious complications in pancreaticoduodenectomy

INTRODUCTION

Infectious complications play a prominent role in pancreaticoduodenectomy. Their incidence increases in cases with preoperative biliary drainage (PBD), due to the higher risk of bacterobilia. The aim of this study is to evaluate an antibiotherapy protocol based on intraoperative gram staining of bile and its impact on postoperative infectious complications.

METHODS

A retrospective study analysing the incidence of infectious complications between two groups of 25 consecutive patients undergoing pancreaticoduodenectomy. In group 1, cefazolin prophylaxis was administered to patients without PBD. In cases with PBD a five days antibiotherapy with piperacillin-tazobactam was administered. In group 2, intraoperative gram staining of bile was routinely performed. If no microorganisms were detected, antibiotherapy was limited to cefazolin prophylaxis. If bacterobilia was detected, targeted antibiotherapy was administered for five days.

RESULTS

The incidence of sepsis and organ/space infection in group 2 was 4% compared to 32% and 24% in group 1 respectively (p<0.05). No differences were observed in the remaining morbimortality variables. The most prevalent microorganisms in bile were Enterococcus spp and Klebsiella spp. In postoperative samples, they only appeared in 4% of cases in group 2 (p<0.05), in favour of S. epidermidis, although they were also prevalent in group 1 (28 and 24% respectively).

CONCLUSION

Intraoperative gram staining of bile fluid could be a useful tool to conduct personalised antibiotic therapy in pancreaticoduodenectomy and contribute to the control of infectious complications.

Achieving 'Marginal Gains' to Optimise Outcomes in Resectable Pancreatic Cancer

Simple Summary

Improving outcomes in pancreatic cancer is achievable through the accumulation of marginal gains. There exists evidence of variation and undertreatment in many areas of the care pathway. By fully realising the existing opportunities, there is the potential for immediate improvements in outcomes and quality of life.

Abstract

Improving outcomes among patients with resectable pancreatic cancer is one of the greatest challenges of modern medicine. Major improvements in survival will result from the development of novel therapies. However, optimising existing pathways, so that patients realise benefits of already proven treatments, presents a clear opportunity to improve outcomes in the short term. This narrative review will focus on treatments and interventions where there is a clear evidence base to improve outcomes in pancreatic cancer, and where there is also evidence of variation and under-treatment. Avoidance of preoperative biliary drainage, treatment of pancreatic exocrine insufficiency, prehabiliation and enhanced recovery after surgery, reducing perioperative complications, optimising opportunities for elderly patients to receive therapy, optimising adjuvant chemotherapy and regular surveillance after surgery are some of the strategies discussed. Each treatment or pathway change represents an opportunity for marginal gain. Accumulation of marginal gains can result in considerable benefit to patients. Given that these interventions already have evidence base, they can be realised quickly and economically.

High incidence of postoperative infections after pancreaticoduodenectomy: A need for perioperative anti-infectious strategies

OBJECTIVES

Postoperative infections occur frequently after pancreaticoduodenectomy, especially in patients with bile colonization. Recommendations for perioperative anti-infectious treatment are lacking, and clinical practice is heterogenous. We have analyzed the effects of bile colonization and antibiotic prophylaxis on postoperative infection rates, types and therapeutic consequences.

METHODS

Retrospective observational study in patients undergoing pancreaticoduodenectomy with intraoperative bile culture. Data on postoperative infections and non-infectious complications, bile cultures and antibiotic prophylaxis adequacy to biliary bacteria were collected.

RESULTS

Among 129 patients, 53% had a positive bile culture and 23% had received appropriate antibiotic prophylaxis. Postoperative documented infection rate was over 40% in patients with or without bile colonization, but antibiotic therapy was more frequent in positive bile culture patients (77% vs. 57%, P=0,008). The median duration of antibiotic therapy was 11 days and included a broad-spectrum molecule in 42% of cases. Two-thirds of documented postoperative infections involved one or more bacteria isolated in bile cultures, which was associated with a higher complication rate. While bile culture yielded Gram-negative bacilli (57%) and Gram-positive cocci (43%), fungal microorganisms were scarce. Adequate preoperative antibiotic prophylaxis according to bile culture was not associated with reduced infectious or non-infectious complication rates.

CONCLUSION

Patients undergoing pancreaticoduodenectomy experience a high rate of postoperative infections, often involving bacteria from perioperative bile culture when positive, with no preventive effect of an adequate preoperative antibiotic prophylaxis. Increased postoperative complications in patients with bile colonization may render necessary a perioperative antibiotic treatment targeting bile microorganisms. Further prospective studies are needed to improve the anti-infectious strategy in these patients.

Escherichia coli Bacterobilia Is Associated with Severe Postoperative Pancreatic Fistula After Pancreaticoduodenectomy

BACKGROUND

The benefit of preoperative biliary stenting in the treatment of pancreatic ductal adenocarcinoma is controversially debated. Data from recent meta-analyses favor primary surgery for the majority of resectable pancreatic cancers. Regardless of this evidence, preoperative biliary stenting via endoscopy (EBS) is commonly performed, often before involvement of a surgeon. The goal of this study was to elucidate the association of bile duct stenting, microbiological dislocation of gut flora to the biliary compartment, and major postoperative complications.

METHODS

Patient data was derived from a prospectively maintained database including all pancreatic resections between January 2006 and December 2014. Patients receiving pancreaticoduodenectomy for malignant disease in the head of the pancreas with prior EBS were included. Microbiological data were obtained through conventional culture from intraoperative bile duct swabs.

RESULTS

Two hundred ninety-eight patients were enrolled in this study. Severe postoperative complications were associated with stent colonization: Postoperative pancreatic fistula type C occurred more frequently in E. coli-colonized patients (sample estimated odds ratio (OR) = 4.07), and the rate of lymphatic fistula was elevated in Enterococcus-colonized patients (OR = 3.25). Longer stenting duration (> 16 days) was associated with the prevalence of these bacteria.

CONCLUSION

Major surgical complications following pancreaticoduodenectomy, including severe pancreatic fistula, are associated with bacterobilia after EBS. The indication for bile duct stenting should be evaluated in a multidisciplinary setting.

Effect of bile duct clamping versus no clamping on surgical site infections in patients undergoing pancreaticoduodenectomy: a randomized controlled study

BACKGROUND

Infectious complications cause significant morbidity after pancreatoduodenectomy (PD). The impact of uncontrolled spillage of bile during PD has not been systematically studied.

METHODS

Patients undergoing PD for malignant lesions between March 2017 and May 2019 were considered for inclusion. All patients underwent standard pre-operative preparation and antibiotic prophylaxis. After confirmation of resectability, the patients were randomized into one of the two groups: common hepatic duct clamping using atraumatic bulldog clamp after biliary division (Group I) or no clamping (Group II). Post-operative outcomes including surgical site infection (SSI) were compared.

RESULTS

Fifty-two patients were assessed for eligibility and eventually 40 were randomized (median age: 53.5 years, 28 (70%) males). Twenty patients were randomized into each group and 14 in each group had undergone pre-operative biliary drainage. Incidence of co-morbidities, operative time and blood loss were comparable between the two groups. SSI was significantly lower in Group I (4 (20%) versus 11 (55%), P = 0.02). Number needed to treat to prevent one SSI was 3. Incidence of intra-abdominal collections was higher in Group II, though, not statistically significant (2 (10%) versus 6 (30%), P = 0.23). The duration of post-operative antibiotics was significantly higher in Group II (7 IQR 4 versus 11 IQR 7 days, P = 0.04). Among the risk factor evaluated in the entire population, higher incidence of SSI was seen in patients with positive bile culture (13 (65%) versus 2 (10%), P = 0.04).

CONCLUSION

Bile duct clamping during PD reduces risk of superficial SSI.

Microbiology of pancreatoduodenectomy and recommendations for antimicrobial prophylaxis

BACKGROUND

The microbiology of pancreatoduodenectomy is challenging and published guidelines regarding perioperative antimicrobial prophylaxis are variable with poor adherence.

METHODS

A retrospective analysis of the microbiological results of 294 consecutive patients who underwent pancreatoduodenectomy was performed. Intraoperative specimen culture results were available for 50 patients and their medical records were reviewed to determine the following demographics and factors; age; sex; tumour location, histopathology, grade and stage; neoadjuvant chemotherapy and radiotherapy; preoperative biliary stenting; surgeon; surgery type and antimicrobial prophylaxis coverage. Outcomes assessed included; post-operative infections, mortality (all and 90-day), and intensive care unit and hospital admission durations. Univariate analysis with chi-squared testing was performed.

RESULTS

Intraoperative specimen cultures were positive in 48 (96%) patients and polymicrobial in 45 (90%) patients with a predominance of Enterobacteriaceae (38/76%), Enterococcus species (27/54%), and Candida species (25/50%). Isolates were potentially susceptible to the current perioperative antimicrobial prophylaxis regimen of ceftriaxone with or without metronidazole in only six patients. However, only neoadjuvant radiotherapy was associated with statistically significant increased intensive care unit and hospital admission durations.

CONCLUSION

Although this study was probably underpowered to detect any statistically significant associations, perioperative antimicrobial prophylaxis coverage of the operative field microbiological milieu of pancreatoduodenectomy is logical and current guidelines may be inadequate.

Bacterobilia in pancreatic surgery-conclusions for perioperative antibiotic prophylaxis

BACKGROUND

Jaundice or preoperative cholestasis (PC) are typical symptoms of pancreatic masses. Approximately 50% of patients undergo preoperative biliary drainage (PBD) placement. PBD is a common cause of bacterobilia (BB) and is a known surgical site infection risk factor. An adjustment of preoperative antibiotic prophylaxis (PAP) may be reasonable according to the profile of BB. For this, we examined the microbiological findings in routine series of patients.

AIM

To investigate the incidence and profile of biliary bacterial colonization in patients undergoing pancreatic head resections.

METHODS

In the period from January 2009 to December 2015, 285 consecutive pancreatic head resections were performed. Indications for surgery were malignancy (71%), chronic pancreatitis (18%), and others (11%). A PBD was in 51% and PC was in 42%. The standard PAP was ampicillin/sulbactam. Intraoperatively, a smear was taken from the hepatic duct. An analysis of the isolated species and resistograms was performed. Patients were categorized according to the presence or absence of PC (PC+/PC-) and PBD (PBD+/PBD-) into four groups. Antibiotic efficiency was analyzed for standard PAP and possible alternatives.

RESULTS

BB was present in 150 patients (53%). BB was significantly more frequent in PBD+ (n =120) than in PBD- (n = 30), P < 0.01. BB was present both in patients with PC and without PC: (PBD-/PC-: 18%, PBD-/PC+: 30%, PBD+/PC-: 88%, PBD+/PC+: 80%). BB was more frequent in malignancy (56%) than in chronic pancreatitis (45%). PBD, however, was the only independent risk factor in multivariate analysis. In total, 357 pathogens (342 bacteria and 15 fungi) were detected. The five most common groups (n = 256, 74.8%) were Enterococcus spp. (28.4%), Streptococcus spp. (16.9%), Klebsiella spp. (12.6%), Escherichia coli (10.5%), and Enterobacter spp. (6.4%). A polymicrobial BB (PBD+: 77% vs PBD-: 40%, P < 0.01) and a more frequent detection of Enterococcus (P < 0.05) was significantly associated with PBD+. In PBD+, the efficiency of imipenem and piperacillin/tazobactam was significantly higher than that of the standard PAP (P < 0.01).

CONCLUSION

PBD-/PC- and PBD-/PC+ were associated with a low rate of BB, while PBD+ was always associated with a high rate of BB. In PBD+ patients, BB was polymicrobial and more often associated with Enterococcus. In PBD+, the spectrum of potential bacteria may not be covered by standard PAP. A more potent alternative for prophylactic application, however, was not found.

The Critical Role of Biliary Candidiasis in Development of Surgical Site Infections after Pancreatoduodenectomy: Results of Prospective Study Using a Selective Culture Medium for Candida Species

In accordance with previous reports, the incidence of biliary candidiasis (BC) after pancreaticoduodenectomy (PD) was reported to be 0 to 5%, and the clinical significance of BC still has been elusive. In this study, we prospectively evaluated the precise incidence of BC after PD using the CHROMagar Candida plate in an attempt to elucidate whether BC has a significant impact on the clinical outcomes after PD. Patients and Method. From November 2014 to March 2016, the consecutive 51 patients who underwent PD were enrolled for this study. The bile juice was prospectively collected through the biliary stent tube on postoperative days (POD) 3, 7, and 14 and directly incubated onto the CHROMagar Candida plate for the cultivation of various Candida species. In the presence or absence of BC, we compared the incidence of SSIs. Results. The incidence of postoperative BC was 15% on POD 3, 24% on POD 7, and 39% on POD 14, respectively. Taken together, 22 patients out of 51 (43.1%) developed BC after PD. Moreover, the incidence of SSIs was significantly higher in patients with BC than in those without it (71% versus 7%, p=0.005). BC was selected as the only significant risk factor of SSIs after PD among the various risk factors. Even though a cause of BC is unknown, high level of alkaline phosphatase (cut-off line >300 IU/L) was selected as the only preoperative risk factor of the development of BC. Conclusion. We elucidated new evidence in which BC could be the independent cause of SSIs after PD and should not be recognized as just contamination artifacts. Preoperative assessment for identifying carriers of Candida species might be essential for reducing the incidence of SSIs after PD.

Efficacy of Pre-Operative Antimicrobial Prophylaxis in Patients Undergoing Pancreatoduodenectomy: A Multi-Center Retrospective Analysis

BACKGROUND

The most common complications after pancreaticoduodenectomy (PD) are infectious, despite the standard use of cefazolin and metronidazole prophylaxis. Pre-operative biliary drainage (PBD) is a well-known risk factor for infectious complications. The objective was to identify the pathogens in intra-operative bile cultures in patients undergoing PD-with and without PBD-to determine the optimal antimicrobial prophylaxis regimen.

PATIENTS AND METHODS

Patients who underwent PD between 2009 and 2016 were identified retrospectively in three major teaching hospitals in The Netherlands. Organisms isolated from intra-operative bile cultures were studied. If pathogen coverage by standard prophylaxis was incomplete, the most appropriate alternative regimen was determined.

RESULTS

Of this large cohort of 352 patients, 56% underwent PBD and 44% did not. Positive bile cultures were found in 87.9% in the PBD group, compared with 31.8% in the non-PBD group. The micro-organisms isolated most commonly were Enterococcus, Streptococcus, and Klebsiella species. Cefazolin and metronidazole were appropriate in only 71% of patients. Adding gentamicin would provide complete coverage in 99% of PBD and 100% of non-PBD patients.

CONCLUSIONS

Our data confirm that PBD prior to PD leads to microbial colonization and antibiotic resistance. To potentially prevent infectious complications, gentamicin may be added to the standard antimicrobial prophylaxis.

Effect of preoperative biliary drainage on bacterial flora in bile of patients with periampullary cancer

BACKGROUND

Patients with obstructive jaundice due to periampullary tumours may undergo preoperative biliary drainage (PBD). The effect of PBD on the microbiome of the biliary system and on postoperative outcome remains unclear.

METHODS

A single-centre retrospective study of patients with obstructive jaundice due to periampullary cancer, treated between July 2007 and July 2015, was undertaken. Intraoperative bile samples were obtained for microbiological analysis after transection of the common bile duct. Postoperative complications were registered.

RESULTS

Of 290 patients treated, intraoperative bile samples were present for 172 patients (59·3 per cent) who had PBD and 118 (40·7 per cent) who did not. Contamination of bile was increased significantly in patients who underwent stenting (97·1 per cent versus 18·6 per cent in those without stenting; P < 0·001). PBD resulted in a shift in the biliary microbiome from Escherichia coli in non-stented patients (45 per cent versus 19·2 per cent in stented patients; P = 0·009) towards increased contamination with Enterococcus faecalis (9 versus 37·7 per cent respectively; P = 0·008) and Enterobacter cloacae (0 versus 20·4 per cent; P = 0·033). This shift was associated with a high incidence of bacterial resistance against ampicillin-sulbactam (63·6 per cent versus 18 per cent in patients with no PBD; P < 0·001), piperacillin-tazobactam (30·1 versus 0 per cent respectively; P = 0·003), ciprofloxacin (28·5 versus 5 per cent; P = 0·047) and imipenem (26·6 versus 0 per cent; P = 0·011). The rate of wound infection was higher in patients with a positive bile culture (21·0 per cent versus 6 per cent in patients with sterile bile; P = 0·002). Regression analysis revealed the presence of Enterococcus faecium (odds ratio 2·83, 95 per cent c.i. 1·17 to 6·84; P = 0·021) and Citrobacter species (odds ratio 5·09, 1·65 to 15·71; P = 0·005) as independent risk factors for postoperative wound infection.

CONCLUSION

There are fundamental differences in the biliary microbiome of patients with periampullary cancer who undergo PBD and those who do not. PBD induces a shift of the biliary microbiome towards a more aggressive and resistant spectrum, which requires a differentiated perioperative antibiotic treatment strategy.

Influence of the Biliary System on Biliary Bacteria Revealed by Bacterial Communities of the Human Biliary and Upper Digestive Tracts

Biliary bacteria have been implicated in gallstone pathogenesis, though a clear understanding of their composition and source is lacking. Moreover, the effects of the biliary environment, which is known to be generally hostile to most bacteria, on biliary bacteria are unclear. Here, we investigated the bacterial communities of the biliary tract, duodenum, stomach, and oral cavity from six gallstone patients by using 16S rRNA amplicon sequencing. We found that all observed biliary bacteria were detectable in the upper digestive tract. The biliary microbiota had a comparatively higher similarity with the duodenal microbiota, versus those of the other regions, but with a reduced diversity. Although the majority of identified bacteria were greatly diminished in bile samples, three Enterobacteriaceae genera (Escherichia, Klebsiella, and an unclassified genus) and Pyramidobacter were abundant in bile. Predictive functional analysis indicated enhanced abilities of environmental information processing and cell motility of biliary bacteria. Our study provides evidence for the potential source of biliary bacteria, and illustrates the influence of the biliary system on biliary bacterial communities.