Antibiotics for Patients With a Planned Re-Laparotomy for Intra-Abdominal Infection

Background: Appropriate antimicrobial therapy for the management of intra-abdominal infection (IAI) continues to evolve based on available literature. The Study to Optimize Peritoneal Infection Therapy (STOP-IT) trial provided evidence to support four days of antibiotic agents in IAI post-source control but excluded patients with a planned re-laparotomy. This study aimed to determine the short- and long-term recurrent infection risk in this population. Patients and Methods: This is a single-center, retrospective, observational study of adult patients admitted to a quaternary medical center between January 1, 2016, and August 1, 2022, with IAI requiring planned laparotomy. Patients were designated as receiving five or less days of antibiotic agents (short course) or more than five days (long course) after source control. The primary outcome was IAI recurrence within 30 days. Results: Of the 104 patients who met inclusion criteria, 78 were included in analysis. Average age was 57 ± 13.3 years, 56% were male, 94% Caucasian, with a mean Acute Physiology and Chronic Health Evaluation (APACHE) II score of 17 ± 7.09. All other baseline characteristics and clinical severity markers were similar between the two groups. Regarding the primary outcome of IAI recurrence, there was no difference when comparing those who received short course versus those who received long course therapy (41.2% vs. 44.4%; p = 0.781). No differences were found between groups with respect to secondary outcomes. Conclusions: In patients admitted with IAI managed with planned re-laparotomy those who received short course antimicrobial therapy were not found to have an increase in IAI recurrence compared to those with longer courses of therapy.

Farnesol remodels the peritoneal cavity immune environment influencing Candida albicans pathogenesis during intra-abdominal infection

Candida albicans is a lifelong member of the mycobiome causing mucosal candidiasis and life-threatening, systemic, and intra-abdominal disease in immunocompromised and transplant patients. Despite the clinical importance of intra-abdominal candidiasis with mortality rates between 40% and 70%, the contribution of fungal virulence factors and host immune responses to disease has not been extensively studied. Secretion of the quorum-sensing molecule, farnesol, acts as a virulence factor for C. albicans during systemic infection, while inducing local, protective innate immune responses in oral models of infection. Previously, we reported that farnesol recruits macrophages to the peritoneal cavity in mice, suggesting a role for farnesol in innate immune responses. Here, we expand on our initial findings, showing that farnesol profoundly alters the peritoneal cavity microenvironment promoting innate inflammation. Intra-peritoneal injection of farnesol stimulates rapid local death of resident peritoneal cells followed by recruitment of neutrophils and inflammatory macrophages into the peritoneal cavity and peritoneal mesothelium associated with an early increase in chemokines followed by proinflammatory cytokines. These rapid inflammatory responses to farnesol significantly increase morbidity and mortality of mice with intra-abdominal candidiasis associated with increased formation of peritoneal adhesions, despite similar rates of fungal clearance from the peritoneal cavity and retro-peritoneal organs. C. albicans ddp3Δ/ddp3Δ knockout and reconstituted strains recapitulate these findings. This indicates that farnesol may be detrimental to the host during intra-abdominal infections. Importantly, our results highlight a need to understand how C. albicans virulence factors modulate the host immune response within the peritoneum, an exceedingly common site of Candida infection.

Protection against lethal sepsis following immunization with Candida species varies by isolate and inversely correlates with bone marrow tissue damage

Protection against lethal Candida albicans (Ca)/Staphylococcus aureus (Sa) intra-abdominal infection (IAI)-mediated sepsis can be achieved by a novel form of trained innate immunity (TII) involving Gr-1+ myeloid-derived suppressor cells (MDSCs) that are induced by inoculation (immunization) with low virulence Candida species [i.e., Candida dubliniensis (Cd)] that infiltrate the bone marrow (BM). In contrast, more virulent Candida species (i.e., C. albicans), even at sub-lethal inocula, fail to induce similar levels of protection. The purpose of the present study was to test the hypothesis that the level of TII-mediated protection induced by Ca strains inversely correlates with damage in the BM as a reflection of virulence. Mice were immunized by intraperitoneal inoculation with several parental and mutant strains of C. albicans deficient in virulence factors (hyphal formation and candidalysin production), followed by an intraperitoneal Ca/Sa challenge 14 d later and monitored for sepsis and mortality. Whole femur bones were collected 24 h and 13 d after immunization and assessed for BM tissue/cellular damage via ferroptosis and histology. While immunization with standard but not sub-lethal inocula of most wild-type C. albicans strains resulted in considerable mortality, protection against lethal Ca/Sa IAI challenge varied by strain was usually less than that for C. dubliniensis, with no differences observed between parental and corresponding mutants. Finally, levels of protection afforded by the Ca strains were inversely correlated with BM tissue damage (R 2 = -0.773). TII-mediated protection against lethal Ca/Sa sepsis induced by Candida strain immunization inversely correlates with BM tissue/cellular damage as a reflection of localized virulence.

Application of metagenomic sequencing of drainage fluid in rapid and accurate diagnosis of postoperative intra-abdominal infection: a diagnostic study

BACKGROUND

Postoperative intra-abdominal infection (PIAI) is one of the most serious complications of abdominal surgery, increasing the risk of postoperative morbidity and mortality and prolonging hospital stay. Rapid diagnosis of PIAI is of great clinical value. Unfortunately, the current diagnostic methods of PIAI are not fast and accurate enough.

METHODS

The authors performed an exploratory study to establish a rapid and accurate diagnostic method of PIAI. The authors explored the turnaround time and accuracy of metagenomic next-generation sequencing (mNGS) in diagnosing PIAI. Patients who underwent elective abdominal surgery and routine abdominal drainage with suspected PIAI were enroled in the study. The fresh midstream abdominal drainage fluid was collected for mNGS and culturing.

RESULTS

The authors found that the median sample-to-answer turnaround time of mNGS was dramatically decreased than that of culture-based methods (<24 h vs. 59.5-111 h). The detection coverage of mNGS was much broader than culture-based methods. The authors found 26 species from 15 genera could only be detected by mNGS. The accuracy of mNGS was not inferior to culture-based methods in the 8 most common pathogens detected from abdominal drainage fluid (sensitivity ranged from 75 to 100%, specificity ranged from 83.3 to 100%, and kappa values were higher than 0.5). Moreover, the composition of the microbial spectrum established by mNGS varied between upper and lower gastrointestinal surgery, enhancing the understanding of PIAI pathogenesis.

CONCLUSION

This study preliminarily revealed the clinical value of mNGS in the rapid diagnosis of PIAI and provided a rationale for further research.

Corrigendum: Acute gastrointestinal injury and altered gut microbiota are related to sepsis-induced cholestasis in patients with intra-abdominal infection: a retrospective and prospective observational study

[This corrects the article DOI: 10.3389/fmed.2023.1144786.].

coli Isolates from Intra-Abdominal Infections in the Asia-Pacific Region: Trends in Ciprofloxacin, Ceftriaxone, Cefepime, and Piperacillin/Tazobactam Susceptibility

Purpose

To investigate the antibiotic susceptibility of Escherichia coli isolates in patients diagnosed with intra-abdominal infections (IAIs) in the Asia-Pacific region.

Patients and Methods

This study was conducted at 50 medical hospitals across 9 countries/regions as part of the Study for Monitoring Antimicrobial Resistance Trends (SMART) surveillance program from 2014 to 2018. Nonduplicate isolates of aerobic and facultative gram-negative bacilli were collected and processed for further antimicrobial susceptibility testing.

Results

A total of 10,709 isolates were collected, with E. coli (n=4737, 44.2%) being the leading pathogen causing IAIs, followed by Klebsiella pneumoniae (n=2429, 22.7%) and Pseudomonas aeruginosa (n=931, 8.7%). Community-associated (CA) E. coli isolates generally exhibited higher susceptibility rates for most antibiotics than hospital-associated (HA) isolates. In countries/regions other than Hong Kong, South Korea, and Singapore, HA isolates displayed lower susceptibility rates for multiple classes (≥4) of antibiotics. Among the commonly used antibiotics in IAIs, the overall susceptibility rate for ciprofloxacin was low, with an average of 41.3%. Ceftriaxone susceptibility rates in all selected countries were below 80% starting in 2018, ranging from 23.3% to 75.8%. The cefepime susceptibility rates varied across regions, with consistently reduced susceptibility ranging from 45.5% to 57.8% in India, Thailand, and Vietnam. Piperacillin/tazobactam demonstrated effectiveness against E. coli isolates in almost all countries except India, with a downward trend observed in the Philippines and Taiwan. Carbapenems remained effective against more than 90% of E. coli isolates, except in India.

Conclusion

Prudent use of fluoroquinolones and ceftriaxone is advised when treating both CA and HA IAIs in the Asia-Pacific region. The low susceptibility rate of cefepime in India, Thailand, and Vietnam needs careful consideration in its administration. Moreover, the increase in nonsusceptibility to piperacillin/tazobactam in the Philippines and Taiwan poses a potential risk that should be closely monitored.

Exploration of a Potential Desirability of Outcome Ranking Endpoint for Complicated Intra-Abdominal Infections Using 9 Registrational Trials for Antibacterial Drugs

BACKGROUND

Desirability of outcome ranking (DOOR) is a novel approach to clinical trial design that incorporates safety and efficacy assessments into an ordinal ranking system to evaluate overall outcomes of clinical trial participants. Here, we derived and applied a disease-specific DOOR endpoint to registrational trials for complicated intra-abdominal infection (cIAI).

METHODS

Initially, we applied an a priori DOOR prototype to electronic patient-level data from 9 phase 3 noninferiority trials for cIAI submitted to the US Food and Drug Administration between 2005 and 2019. We derived a cIAI-specific DOOR endpoint based on clinically meaningful events that trial participants experienced. Next, we applied the cIAI-specific DOOR endpoint to the same datasets and, for each trial, estimated the probability that a participant assigned to the study treatment would have a more desirable DOOR or component outcome than if assigned to the comparator.

RESULTS

Three key findings informed the cIAI-specific DOOR endpoint: (1) a significant proportion of participants underwent additional surgical procedures related to their baseline infection; (2) infectious complications of cIAI were diverse; and (3) participants with worse outcomes experienced more infectious complications, more serious adverse events, and underwent more procedures. DOOR distributions between treatment arms were similar in all trials. DOOR probability estimates ranged from 47.4% to 50.3% and were not significantly different. Component analyses depicted risk-benefit assessments of study treatment versus comparator.

CONCLUSIONS

We designed and evaluated a potential DOOR endpoint for cIAI trials to further characterize overall clinical experiences of participants. Similar data-driven approaches can be utilized to create other infectious disease-specific DOOR endpoints.

Acute gastrointestinal injury and altered gut microbiota are related to sepsis-induced cholestasis in patients with intra-abdominal infection: a retrospective and prospective observational study

Background

Sepsis-associated liver dysfunction (SALD) has high incidence and mortality in patients with intra-abdominal infection (IAI). The associations between acute gastrointestinal injury (AGI), gut microbiota, and SALD were evaluated in patients with IAI.

Methods

A retrospective study was conducted to assess the relationship between AGI and SALD in patients with IAI. Patients were divided into non-SALD and sepsis-induced cholestasis (SIC) groups, which is a subtype of SALD. SIC was defined as total bilirubin >2 mg/dL. AGI incidences between the two groups were compared using Chi-square test. Subsequently, a prospective study was conducted to investigate the gut microbiota differences between patients without SALD and those with SIC. Fecal samples were collected on days 1, 3, and 7 after admission to analyze changes in gut microbiota using 16S ribosomal ribonucleic acid sequencing.

Results

One hundred thirty-four patients with IAI were included retrospectively, with 77 SALD and 57 non-SALD cases. Among patients with SALD, 71 were diagnosed with SIC. Patients with SIC had a higher incidence of AGI compared to those without SALD (28.07% vs. 56.34%, p < 0.05), and a severity-dependent relationship was found between AGI grade and SIC occurrence. Subsequently, 20 patients with IAI were recruited prospectively, with 10 patients each assigned to the non-SALD and SIC groups. Patients with SIC had a more severe gut microbiota disorder on day 7 than those without SALD, including lower microbiota diversities, decreased abundance of Firmicutes and Bacteroidetes, and increased abundance of Proteobacteria and Actinobacteria at the phylum level. Furthermore, Burkholderia - Caballeronia - Paraburkholderia and Delftia, the two most abundant genera, were significantly higher in the SIC group than in the non-SALD group. Functional prediction analysis showed that the top three KEGG pathways were ribosome, pyrimidine metabolism, and the two-component system. During the first week, the abundance of Proteobacteria decreased significantly, whereas Cyanobacteria increased in the non-SALD group; however, the phyla taxa did not change significantly in the SIC group.

Conclusion

There exists a severity-dependent relationship between AGI grade and SIC occurrence in adult patients with IAI. A severe gut microbiota disorder was discovered in SIC during the first week of the intensive care unit stay.

Portal-Mesenteric Suppurative Emphysematous Pylephlebitis: A Case Report

Suppurative thrombophlebitis of the portal-mesenteric venous system occurring in the setting of abdominal inflammatory and infectious processes is a serious condition that can lead to septic shock, bowel ischemia, hepatic abscess, and death if unrecognized. Diagnosis is often delayed because symptoms are aspecific and pain at the primary site of infection may be mild. Contrast-enhanced CT scans can diagnose both portal thrombosis and a primary infection site. Treatment may include early resective surgery in case of appendicitis or diverticulitis, in association with large-spectrum antibiotics and possibly anticoagulation. A characteristic of suppurative thrombophlebitis, whether splanchnic or systemic, is the latency before the effects of antibiotic therapy are seen. Anticoagulation can be administered to avoid extension to the superior mesenteric vein. We presented a critically ill 53-year-old man with chronic colonic diverticulitis complicated by suppurative emphysematous portal-mesenteric thrombophlebitis with only a slow response to large-spectrum antibiotics.

Antibiotic Practice in Patients With Acute Abdomen Admitted to a Danish Regional Hospital: A Clinical Qualitative Assurance Study

Background Acute abdomen is often complicated by intra-abdominal infection requiring antibiotic therapy. Danish regional antibiotic guidelines emphasize the restricted use of broad-spectrum antibiotics such as cephalosporins. In this study, we aimed to evaluate antibiotic practices in relation to hospitalized patients with acute abdomen. Methodology This retrospective quality assurance study was conducted among patients admitted to the surgical emergency department at the North Denmark Regional Hospital during a four-month observation period. Data were extracted from electronic patient journals and entered in the Research Electronic Data Capture data management system for further analytical work. Results Of 331 patients, 174 (53%) were treated with antibiotics, of whom 98 (56%) had been treated with cephalosporin, 47 (27%) with benzylpenicillin and gentamicin, 22 (13%) with piperacillin/tazobactam, and seven (4%) with ciprofloxacin. Use of a cephalosporin-based antibiotic regimen was significantly more common in patients with acute appendicitis (75%) compared to other diagnostic groups, such as acute cholecystitis (57%), incarcerated hernia with strangulation (56%), acute pancreatitis (50%), and acute diverticulitis (30%). However, patients with uncomplicated diverticulitis (53%) were significantly more often treated with benzylpenicillin and gentamicin, whereas patients with complicated diverticulitis Hinchey stage 3-4 were significantly more often treated with piperacillin/tazobactam. In addition, as the severity of acute cholecystitis increased, it was more frequently treated with piperacillin/tazobactam. Conclusions The study revealed that cephalosporins are frequently used in patients hospitalized with acute abdomen. This finding conflicts with current regional antibiotic guidelines. Reinforcement of the guidelines is required as an essential measure against the development of antibiotic resistance associated with the use of cephalosporins.

Reduction of Surgical Site Infection After Trauma Laparotomy Through Use of a Specific Protocol for Antibiotic Prophylaxis

Background: Emergency laparotomy for abdominal trauma is associated with high rates of surgical site infection (SSI). A protocol for antimicrobial prophylaxis (AMP) for trauma laparotomy was implemented to determine whether SSI could be reduced by adhering to established principles of AMP. Patients and Methods: A protocol utilizing ertapenem administered immediately before initiation of trauma laparotomy was adopted. Compliance with measures of adequate AMP were determined before and after protocol implementation, as were rates of SSI and other infections related to abdominal trauma. Univariable and multivariable analyses were performed to determine risk factors for development of infection related to trauma laparotomy. Results: Over a four-year period, 320 patient operations were reviewed. Ertapenem use for prophylaxis increased to 54% in the post-intervention cohort. Compliance with individual measures of appropriate AMP improved modestly. Overall, infections related to trauma laparotomy decreased by 46% (absolute decrease of 13%) in the post-intervention cohort. Multivariable analysis confirmed that treatment during the post-intervention phase was associated with this decrease, with a separate analysis suggesting that ertapenem use was an important factor in this decrease. Conclusions: Development of a standardized protocol for AMP in trauma laparotomy led to decreases in infectious complications after that procedure.

[Clostridium tertium bacteremia in patient with liver cirrhosis]

Clostridium tertium is a bacterium of the Clostridiaceae family which can be found colonizing the gastrointestinal tract. Unlike other members of its family, it does not produce exotoxins. It was described for the first time in 1917 and in 1963 it was established as a pathogen in humans. Since then, cases have been reported mainly in immunosuppressed hosts, predominantly with primary focus at the abdominal level. The case of a 48-year-old man with a history of cirrhosis and hepatitis C virus infection is described. He presented an obstructed umbilical hernia that required intestinal resection and anastomosis, with positive blood and abdominal fluid cultures for Clostridium tertium. This case is of clinical importance due to the low prevalence of this germ, the possibility of resistance to usual antibiotic regimens and its sub diagnostic given the morphological and growth similarities with Bacillus or Lactobacillus.

Outcomes of Beta-Lactam Allergic and Non-Beta-Lactam Allergic Patients with Intra-Abdominal Infection: A Case-Control Study

Background: In the case of intra-abdominal infections (IAI) in beta-lactam (BL) allergic patients, empiric antimicrobial therapy without BL is recommended; however, data regarding the outcome with alternative regimens are scarce. This study aimed to compare the outcomes of BL allergic (BLA) patients with IAI to those who were non-BLA (NBLA). Method: We conducted a case−control study in a French teaching hospital, between 1 January 2016 and 31 August 2021. BLA patients with IAI treated with fluoroquinolone or aztreonam and metronidazole were matched with controls treated with BL, on age, sex, disease severity, IAI localization, and healthcare-associated infection (HAI) status. We compared rates of therapeutic failures, adverse events, and HAI, and then assessed factors associated with therapeutic failure using a logistic regression model. Results: The therapeutic failure rate was 14% (p > 0.99) in both groups of 43 patients, and there was no significant difference in the adverse events rate (p > 0.99) and HAI rate (p = 0.154). Factors independently associated with therapeutic failure were higher BMI (OR 1.16; 95%CI [1.00−1.36]; p = 0.041), longer hospital length of stay (OR 1,20; 95%CI [1.08−1.41]; p = 0.006), and inadequate empiric antimicrobial therapy (OR 11.71; 95%CI [1.43−132.46]; p = 0.025). Conclusion: The outcomes of BLA patients with IAI treated without BL were the same as those for NBLA patients treated with BL.

Effectiveness of Five Antibiotic Regimens for the Treatment of Intra-Abdominal Infection in Bogotá

Background: Intra-abdominal infection (IAI) results in prolonged in-hospital length-of-stay, critical care unit requirements, and multiple surgical procedures. Several antimicrobial agents are available for treatment of IAI. In Colombia, there are no data on the comparative effectiveness of the different regimens used. Patients and Methods: A multicenter retrospective cohort study was completed in four third-level hospitals by comparing treatment effectiveness of five different antibiotic protocols (ampicillin-sulbactam, clindamycin-amikacin, piperacillin-tazobactam, amikacin-metronidazole, and cefuroxime-metronidazole) in patients with a diagnosis of IAI. Analysis was based on a composed outcome of therapeutic failure (change of antibiotic because of no clinical improvement, requirement of surgical re-intervention, post-operative infection, change of antibiotic because of antimicrobial resistance, and in-hospital mortality). Association of each antibiotic protocol to therapeutic failure was assessed through logistic regression analysis. Results: Five hundred ninety-three individuals were included. Two hundred twenty-nine were prescribed ampicillin-sulbactam; 170, clindamycin-amikacin; 77, amikacin-metronidazole; 83, piperacillin-tazobactam; and 34, cefuroxime-metronidazole. Therapeutic failure rate was 22%. Multivariable analysis showed none of the evaluated antibiotic protocols had an association with the primary outcome. Variables having an association for higher risk were age >70 years old (odds ratio [OR], 2.08; 95% confidence interval [CI], 1.04-4.18); complicated IAI (OR, 3.36; 95% CI, 1.4-8.07); and World Society of Emergency Surgery (WSES) Sepsis Severity Score (OR, 1.31; 95% CI, 1.18-1.45). Adequate source control (OR, 0.16; 95% CI, 0.05-0.45) and hospitalization at Health Center 2 (OR, 0.30; 95% CI, 0.14-0.63) were identified as protective factors. Conclusions: There are no differences between the rate of therapeutic failure among the different antibiotic protocols evaluated. This outcome depends heavily on risk factors related to disease severity when surgical intervention occurs.

Early detection of anastomotic leak with C-reactive protein increases the chances of anastomotic salvage

AIM

Anastomotic leak results in increased morbidity and affects functional and oncological outcomes after colectomy. Measurement of C-reactive protein (CRP) allows early detection of anastomotic leaks. The aim of this study was to evaluate the benefit to the patient of earlier diagnosis and management of anastomotic leaks, namely avoiding takedown of the anastomosis.

METHOD

Patients with an anastomotic fistula after elective colorectal surgery from 2010 to 2020 were included. Three periods were defined according to progressive adherence to the CRP protocol in our department. A comparison was made between the periods 'before' (2010-2013) and 'after' (2016-2020) in terms of morbidity, mortality, anastomotic salvage, days spent in hospital within the first postoperative month, timely adjuvant chemotherapy and anastomotic stenosis.

RESULTS

Out of 2655 elective colorectal operations, 171 patients presented with an anastomotic leak and 123 patients were included in the study. In univariate analysis, patients in the 'after' group had fewer severe complications (Clavien-Dindo Grade III to IV, 66.7% vs. 56.9; p = 0.017); the difference did not reach significance regarding timely postoperative chemotherapy (p = 0.058) and anastomotic stenosis (p = 0.682). In both, univariate and multivariate analysis, the 'after' period increased the chances of preserving the anastomosis (OR = 2.37 [1.08-5.17]) and increased the number of days out of hospital (p = 0.0002).

CONCLUSION

A CRP-based protocol for the screening of anastomotic leaks after colorectal surgery was related to increased anastomotic conservation, a decreased impact and severity of the leak and a shorter length of hospital stay.

Pylephlebitis: A Rare Complication of Acute Appendicitis

Pylephlebitis is defined as an infective suppurative thrombosis of the portal vein and its tributaries - a rare complication of intra-abdominal infections. It is most commonly seen in patients with diverticulitis and appendicitis. Prompt diagnosis with abdominal ultrasound and computerized tomography (CT) scan along with early and aggressive treatment with broad-spectrum antibiotics is crucial because of its high mortality rates. However, this diagnosis is often missed due to the nature of its nonspecific clinical symptoms. We discuss a case of a 22-year-old male who presented with pylephlebitis as a complication of acute gangrenous appendicitis. The patient was treated successfully with appropriate surgical intervention, antibiotics, and anticoagulation.

Population Pharmacokinetics of Temocillin Administered by Continuous Infusion in Patients with Septic Shock Associated with Intra-Abdominal Infection and Ascitic Fluid Effusion

Temocillin is active against Gram-negative bacteria, including many extended-spectrum β-lactamase (ESBL)-producing Enterobacterales. We studied its pharmacokinetics in plasma and ascitic fluid after intravenous administration of a loading dose of 2 g over 30 min, followed by continuous infusion of 6 g/24 h, to 19 critically-ill patients with septic shock associated with complicated intra-abdominal infection. We established a pharmacokinetic model describing unbound temocillin concentrations in plasma and ascitic fluid and performed Monte-Carlo simulations to evaluate the probability of target attainment (PTA) of unbound concentrations (100% fT > MIC, i.e., unbound concentrations remaining above the MIC during 100% of the time) for the applied and hypothetical dosing regimens. The temocillin AUC in ascitic fluid was 46% of the plasma AUC. Plasma unbound concentrations were best described by a two-compartment model, and an additional compartment was added to describe unbound concentration in ascitic fluid, with renal clearance as a covariate. Dosing simulations showed that 90% PTA was achieved in the plasma with the current dosing regimen for MIC ≤ 16 mg/L (EUCAST susceptibility breakpoint) but not in the ascitic fluid if renal clearance was ≥40 mL/min. Hypothetical dosing with a higher (a) loading dose or (b) infused dose allowed to reach target concentrations in ascitic fluid (a) more rapidly or (b) sustainably, but these simulations need to be evaluated in the clinics for safety and efficacy.

Epidemiology and Age-Related Mortality in Critically Ill Patients With Intra-Abdominal Infection or Sepsis: An International Cohort Study

BACKGROUND

The objective of this study is to describe the epidemiology and age-related mortality in older critically ill adults with intra-abdominal infections.

METHODS

This is a secondary analysis of a prospective, multinational, observational study (AbSeS, ClinicalTrials.gov #NCT03270345) including patients with intra-abdominal infection from 309 ICUs in 42 countries (January-December, 2016). Mortality was considered as ICU mortality with a minimum of 28 days of observation when patients were discharged earlier. Relationships with mortality were assessed by logistic regression analysis.

RESULTS

The cohort included 2337 patients. Four age groups were defined: middle-aged patients as reference category (40-59 years; n=659 [28.2%]), young-old (60-69 years; n=622 [26.6%]), middle-old (70-79 years; n=667 [28.5%]) and very-old patients (≥80 years; n=389 [16.6%]). Secondary peritonitis was the predominant infection (68.7%) and equally prevalent across age groups. Mortality increased with age: 20.9% in middle-aged patients, 30.5% in young-old, 31.2% in middle-old, and 44.7% in very-old patients (p<0.001). Compared to middle-aged patients, young-old age (OR 1.62, 95% CI 1.21-2.17), middle-old age (OR 1.80, 95% CI 1.35-2.41), and very-old age (OR 3.69, 95% CI 2.66-5.12) were independently associated with mortality. Other independent risk factors for mortality included late-onset hospital-acquired intra-abdominal infection, diffuse peritonitis, sepsis/septic shock, source control failure, liver disease, congestive heart failure, diabetes, and malnutrition.

CONCLUSIONS

For ICU patients with intra-abdominal infections, age above 60 years was associated with mortality while patients above 80 years had the worst prognosis. Comorbidities and overall disease severity further compromised survival. As all these factors are non-modifiable it remains unclear how to improve outcomes.

Characteristics of pathogenic bacteria in intra-abdominal infection and risk factors for septic shock in patients with liver cirrhosis

OBJECTIVE

To explore the characteristics of pathogenic bacteria in intra-abdominal infection and the risk factors for septic shock in patients with liver cirrhosis.

METHODS

This retrospective study analyzed the clinical data of patients with cirrhosis admitted to the Department of Infectious Diseases of the 910^th Hospital of Chinese People's Liberation Army, who were divided into an intra-abdominal infection group (n=145) and non-infection group (n=100). We analyzed the risk factors for intra-abdominal infection in patients with liver cirrhosis, and further conducted bacterial culture for patients with intra-abdominal infection to investigate the distribution of pathogenic bacteria and analyzed the risk factors for septic shock.

RESULTS

Multivariate regression analysis found that age (P=0.005), length of hospital stay (P=0.024), invasive operation (P=0.002), and hypoproteinemia (P=0.026) were risk factors for intra-abdominal infection in patients with cirrhosis. 65 of the 145 patients with intra-abdominal infection were tested to be pathogen-positive, with a positivity rate of 44.83%. A total of 118 strains were isolated from the samples of 65 patients with positive test results. Among the 118 strains, 74 of them were gram-negative bacteria (62.71%), 41 were gram-positive bacteria (34.75%), and 3 were fungus (2.54%). Multivariate regression analysis found that age (P=0.003), length of stay (P=0.001), invasive operations (P=0.024) and hypoproteinemia (P=0.001) were all risk factors for septic shock in patients with liver cirrhosis combined with intra-abdominal infection.

CONCLUSION

Age, length of hospital stay, invasive operation, and hypoproteinemia are risk factors for intra-abdominal infection and septic shock in patients with cirrhosis, and gram-negative bacteria are the main pathogens in associated intra-abdominal infection.

Intra-abdominal Streptococcus agalactiae infection associated with myelofibrosis treated with ruxolitinib: a case report of an atypical clinical presentation

BACKGROUND

Post-essential thrombocythemia myelofibrosis (post-ET MF) is a type of Philadelphia chromosome-negative MF. Patients with MF treated with ruxolitinib are immunosuppressed, and therefore more at risk of infection. Several opportunistic infections can occur in the first 6 months of ruxolitinib treatment. However, cases of MF complicated by intra-abdominal Streptococcus agalactiae infection during treatment with ruxolitinib are rare.

CASE REPORT

We report the case of a 42-year-old female patient who had resumed ruxolitinib at 20 mg twice daily on 28 February 2020 and was referred for management of JAK2^V617F-positive post-ET MF on 24 April 2020. She complained of progressive abdominal distention 1 week before admission. During hospitalization, she experienced an abrupt episode of middle-grade fever without chills or peritoneal irritation. Subsequently, S. agalactiae (Group B Streptococcus, GBS) was isolated twice from ascites cultures, and an intra-abdominal infection was diagnosed. The infection was successfully treated using meropenem.

CONCLUSIONS

Our case indicates that ruxolitinib is a risk factor for GBS infection in MF patients. Accurate pathogen identification is critical for effective antimicrobial treatment and improved patient outcomes.

Metagenomic Next-Generation Sequencing for the Microbiological Diagnosis of Abdominal Sepsis Patients

Objectives

For patients with intra-abdominal infection (IAI), the rapid and accurate identification of pathogens remains a challenge. Metagenomic next-generation sequencing (mNGS) is a novel technique for infectious diseases, but its application in IAI is limited. In this study, we compared the microbiological diagnostic ability of plasma mNGS with that of conventional peritoneal drainage (PD) culture in critical care settings.

Methods

From January 2018 to December 2020, a prospective observational study was performed at a tertiary teaching hospital in China and data on 109 abdominal sepsis patients were collected. The pathogen detection performance of plasma mNGS and PD culture method were compared.

Measurements and Results

Ninety-two positive cases detected on PD culture, while plasma mNGS detected 61 positive cases. Forty-five patients (44.0%) had at least one matched pair of plasma mNGS and PD culture results. Compared with PD culture, the plasma mNGS was more rapid (27.1 ± 4.0 vs. 68.9 ± 22.3 h, p < 0.05). The patients received initial antibiotic treatment matched with mNGS detection showed better clinical outcomes.

Conclusion

For abdominal sepsis patients, plasma mNGS can provide early, noninvasive, and rapid microbiological diagnosis. Compared with conventional PD smear, culture, and blood culture methods, plasma mNGS promote the rapid detection of pathogenic bacteria.

Ceftazidime-Avibactam as Salvage Treatment for Infections Due to Carbapenem-Resistant Klebsiella pneumoniae in Liver Transplantation Recipients

Background

Ceftazidime-avibactam (CZA) has been approved in vitro activity against carbapenem-resistant K. pneumoniae (CRKP), but the experience for the treatment of CRKP in liver transplantation (LT) recipients was limited, and previous data on its efficacy in this setting are lacking.

Methods

LT recipients with CRKP infection who received CZA treatment were reviewed retrospectively, microbiological and clinical response, adverse events were also assessed. The primary outcome was 30-day mortality after CZA administration.

Results

CZA was used in 21 LT recipients (including 4 pediatric patients) with CRKP infections after failure with other antimicrobials. CZA was administered as monotherapy in 4 patients. Median time from the onset of CRKP infection until the initiation of CZA treatment was 2 days (IQR, 1–6.5), and the median treatment duration was 12 days (IQR, 8.5–18.5). The mortality at 14 days, 30 days and all-cause was 28.6%, 38.1% and 42.9%, respectively. In adult patients, clinical response of 14 days and 30 days was 70.6% (12/17) and 58.8% (10/17), respectively, while in pediatric patients the 14-day and 30-day clinical response were both 75%, respectively. The relapse rate during the treatment developed in 3 patients after 30 days with the cessation of CZA monotherapy. CZA resistance was not detected in any case and 3 (3/21, 14.3%) patients developed acute kidney injury related to uncontrolled infection.

Conclusion

CZA shows promising results, even in monotherapy, for the treatment of patients with severe infections due to carbapenem-resistant K. pneumoniae among LT recipients. The emergence of resistance to CZA was not observed.

Composite Inflammatory Indicators as Early Predictor of Intra-abdominal Infections after General Surgery

Objective

To identify rapid and accurate early diagnostic indicators for intra-abdominal infection (IAI) after general surgery.

Methods

We conducted a retrospective analysis of 3,810 general surgical patients in our hospital from August 2017 to July 2018. The predictive value of PCT, CRP, TNFα, and IL6 on postoperative days (PODs) 1 and 3 and composite indicators for complicated IAIs among surgical patients was clarified.

Results

There were 271 patients in the infected group and 614 patients in the uninfected group using IAI diagnostic criteria in this study. CRP, PCT, TNFα, and IL6 in the infected group were significantly higher than the uninfected group on POD1 and POD3. In the infected group, the composition of the four indicators on POD1 (AUC 0.819) and POD3 (AUC 0.848) showed higher predictive efficiency than the individual indicators (AUC 0.670-0.805).

Conclusion

The composite of CRP, PCT, TNFα, and IL6 can be used as a predictor of postoperative abdominal infectious complications with high sensitivity and specificity on POD1 and POD3, which can provide a basis for early diagnosis of postoperative abdominal infectious complications.

Development and Validation of a Predictive Scoring System for In-hospital Death in Patients With Intra-Abdominal Infection: A Single-Center 10-Year Retrospective Study

Objective: To develop and validate a scoring system to predict the risk of in-hospital death in patients with intra-abdominal infection (IAI).

Materials and Methods: Patients with IAI (n = 417) treated at our hospital between June 2010 and May 2020 were retrospectively reviewed. Risk factors for in-hospital death were identified by logistic regression analysis. The regression coefficients of each risk factor were re-assigned using the mathematical transformation principle to establish a convenient predictive scoring system. The scoring system was internally validated by bootstrapping sample method.

Results: Fifty-three (53/417, 12.7%) patients died during hospitalization. On logistic regression analysis, high APACHE II score (P = 0.012), pneumonia (P = 0.002), abdominal surgery (P = 0.001), hypoproteinemia (P = 0.025), and chronic renal insufficiency (P = 0.001) were independent risk factors for in-hospital death. On receiver operating characteristic curve analysis, the composite index combining these five risk factors showed a 62.3% sensitivity and 80.2% specificity for predicting in-hospital death (area under the curve: 0.778; 95% confidence interval: 0.711–0.845, P < 0.001). The predictive ability of the composite index was better than that of each independent risk factor. A scoring system (0–14 points) was established by re-assigning each risk factor based on the logistic regression coefficient: APACHE II score (10–15 score, 1 point; >15 score, 4 points); pneumonia (2 points), abdominal surgery (2 points), hypoproteinemia (2 points), and chronic renal insufficiency (4 points). Internal validation by 1,000 bootstrapping sample showed relatively high discriminative ability of the scoring system (C-index = 0.756, 95% confidence interval: 0.753–0.758).

Conclusions: The predictive scoring system based on APACHE II score, pneumonia, abdominal surgery, hypoproteinemia, and chronic renal insufficiency can help predict the risk of in-hospital death in patients with IAI.

Peritoneal Tuberculosis in a Young Healthy Male Resembling Intra-Abdominal Malignancy

Intra-peritoneal tuberculosis is a rare disease, accounting for 1-2% of all tuberculosis cases. The absence of characteristic clinical picture of intra-peritoneal tuberculosis makes the diagnosis rarely easy for clinicians as it mimics malignancy. We present a case of a young male patient who presented with peritoneal tuberculosis, aiming to contribute to a better understanding of peritoneal tuberculosis in the literature.

Impact of the COVID-19 Pandemic on Survival in the Patients With the Intra-Abdominal Infections

Objective: To analyze the availability and access to the hospital for the patients with intra-abdominal infections (IAIs) by Escherichia coli (E. coli) as a result of the coronavirus disease 2019 (COVID-19) pandemic and the impact of these changes in the diagnosis and their effects on the death of these patients.

Methods: Two prospective observational cohorts of the patients with IAI by E. coli were conducted in 2016 (the pre-COVID-19, n = 108) and in 2020 (during the COVID-19, n = 96) at the University Hospital of Seville, Spain. The demographic and clinical variables of the patients were collected and analyzed. The patients were followed-up for 120 days, until the hospital discharge or death. The bivariate and multivariate analyses were performed.

Results: Both the cohorts were homogeneous according to age, sex, emergency surgery cause, immunosuppression, neutropenia, acquisition type, and previous intervention. The patients attended during the COVID-19 had significantly higher Charlson comorbidity index and the more McCabe score, required more emergency surgery, had more severe infections with the higher rates of septic shock and sepsis, and the presence of additional care support such as a nasogastric tube. They were diagnosed later; the time intervals between the symptoms onset (SO) to the first medical contact or surgical intervention (SI) and between the first medical contact to the admission or SI were significantly higher. The death rates during the COVID-19 and the pre-COVID-19 were 16.7 and 6.5%, respectively (p = 0.02). Finally, the multivariate analysis in both the cohorts together identified the patients diagnosed during the COVID-19, the longer period from SO to SI, septic shock, and the Charlson comorbidity index as the independent factors associated with death.

Conclusion: This study showed the impact of the COVID-19 pandemic on the clinical outcome and death due to IAI with an extension of the time between SO and SI.

Uterine Dehiscence: A Rare Cause of Postpartum Puerperal Sepsis

Uterine dehiscence (partial or complete) is a rare complication of lower segment cesarean section (LSCS). Puerperal sepsis with intra-abdominal abscess following this event has been rarely reported. The delay in diagnosis and management of the condition can result in significant morbidity and mortality. We herein report three cases of puerperal sepsis along with intra-abdominal abscess associated with uterine dehiscence following LSCS. These patients in the current case series presented with complaints of fever and abdominal pain. Early recognition and prompt treatment with diagnostic laparoscopy and or laparotomy with drainage were effective in the management of these patients.

Factors Influencing the Prognosis of Patients with Intra-Abdominal Infection and Its Value in Assessing Prognosis

Purpose

To explore the distribution of pathogenic bacteria in patients with intra-abdominal infection, to clarify the independent factors that affect the prognosis of patients with intra-abdominal infection and its evaluation value for prognosis.

Patients and Methods

The pathogens, underlying diseases, and related clinical data of patients with intra-abdominal infection from January 2012 to December 2019 in our hospital were retrospectively collected and the APACHE II score was calculated. The patients were divided into survival group and death group according to the prognosis, and the index between the two groups was compared. Spearman correlation analysis was used to evaluate the correlation between each index and prognosis, multivariate logistic regression analysis was used to screen the independent prognostic factors.

Results

Spearman correlation analysis showed that ALB level was negatively correlated with prognosis, age and APACHE II score were positively correlated with prognosis. Logistic regression analysis showed that age, ALB level, and APACHE II score were independent prognostic factors. The formula of age combined ALB level and APACHE II score was Y = X1-3.6X2 + 6.5X3 (X1 was the age, X2 was the ALB level and X3 was the APACHE II score), Y was positively correlated with poor prognosis, and the optimal cutoff value was Y = 40.96.

Conclusion

Age, ALB level, and APACHE II score are independent factors that influencing the prognosis of patients with intra-abdominal infection, and the combination of age, ALB level, and APACHE II score can better assess the prognosis of patients with intra-abdominal infection.

The PCT to Albumin Ratio Predicts Mortality in Patients With Acute Kidney Injury Caused by Abdominal Infection-Evoked Sepsis

Purpose: Considerable evidence suggests that inflammation and malnutrition are common in patients with acute kidney injury (AKI) and correlated with mortality of various diseases. Despite this, few studies have reported the underlying predictive effects of inflammatory and nutritional markers in combination on the mortality of AKI patients. Herein, we aimed to explore the values of PCT and CRP as well as the ratios of PCT/Alb and CRP/Alb in the poor prognosis of patients with sepsis-induced AKI.

Patients and Methods: A total of 171 patients with AKI, caused by abdominal infection-evoked sepsis, were retrospectively studied and divided into a survival group (107 cases) and a non-survival group (64 cases). Univariate analysis was used to compare the clinical data of the two groups. Multivariate logistic regression analysis was used to analyze the independent risk factors of poor prognosis in patients with sepsis-induced AKI. The ROC curve was used to evaluate the diagnostic value of PCT, CRP, PCT/Alb, and CRP/Alb in the poor prognosis of patients with sepsis-induced AKI.

Results: Univariate analysis revealed that the values of PCT, CRP, CRP/Alb, and PCT/Alb were significantly different between AKI survival and non-survival groups, and further analysis found that PCT and PCT/Alb were independent risk factors for poor prognosis in patients with sepsis-induced AKI after adjusting with age and gender. Of note, the predictive accuracy (0.864 vs. 0.807), specificity (83.2 vs. 69.2), and sensitivity (79.7 vs. 76.6) of PCT/Alb were all higher than that of the simple PCT.

Conclusions: The ratio of PCT to Alb is an independent risk factor possessing a robust and accurate risk assessment for the poor prognosis of patients with sepsis-induced AKI, and it offers the potential to improve the management of this type of disease and a lower resultant mortality.

Lawsonella clevelandensis is a rare cause of infected chronic contained rupture of abdominal aortic aneurysm

Lawsonella clevelandensis is an anaerobic, partially acid-fast, Gram-positive bacillus associated with abscess formation. We present the case of a 70-year-old male with chronic contained rupture of abdominal aortic aneurysm (CCR-AAA) complicated by intra-abdominal abscess formation. An abdominal computed tomography scan revealed a rim-enhancing retroperitoneal collection tracking into the subcutaneous layer of the left flank and buttock, suggestive of CCR-AAA with infected haematoma. He underwent ultrasound-guided needle aspiration of the intra-abdominal collection. Conventional culture techniques failed to isolate L. clevelandensis, and the diagnosis was only confirmed by means of 16S rRNA PCR. The patient underwent branched endovascular repair of his aneurysm, and was commenced on treatment with co-amoxiclav, resulting in significant reduction in the size of the infected collection. This is only the second reported case of infection with L. clevelandensis in the UK, and the first reported case of this organism causing infected CCR-AAA.

Penetration of Isavuconazole in Ascites Fluid of Critically Ill Patients

Fungal peritonitis is a life-threatening condition which is not only difficult to diagnose, but also to treat. Following recent guidelines, echinocandins and azoles are the recommended antimycotics for the management of intra-abdominal Candida spp. infections, with a favor for echinocandins in critically ill patients. However, the new extended spectrum triazole isavuconazole also has a broad spectrum against Candida spp. Data on its target-site penetration are sparse. Therefore, we assessed isavuconazole concentrations and penetration ratios in ascites fluid of critically ill patients. Obtaining of Isavuconazole plasma and ascites fluid levels as well penetration ratios using paracentesis in critically ill patients. Isavuconazole concentrations were quantified in human plasma and ascites by a liquid chromatography/tandem mass spectrometry (LC-MS/MS) method. Isavuconazole concentrations in plasma and ascites fluid were measured in sixteen critically ill patients. Isavuconazol levels in ascites fluid (1.06 µg/mL) were lower than plasma levels (3.08 µg/mL). Penetration ratio was 36%. In two out of sixteen patients, Candida spp., in detail C. glabrata and C. tropicalis, could be isolated. Cmax/MIC Ratio in plasma of 560 for C. glabrata and 2166 for C. tropicalis could be observed. Following our results, isavuconazole penetrates into ascites. Successful treatment in Candida spp. peritonitis depends on pathogen susceptibility.

Consecutive antibiotic shortages highlight discrepancies between microbiology and prescribing practices for intra-abdominal infections

Piperacillin-tazobactam (TZP) is frequently used for intra-abdominal infection (IAI). Our institution experienced consecutive shortages of TZP and cefepime, providing an opportunity to review prescribing patterns and microbiology for IAI. Hospitalized adult patients treated for IAI, based on provider selection of IAI as the indication within the antibiotic order, between March 2014 and February 2018 were identified from the University of Virginia Clinical Data Repository and Infection Prevention and Control Database. Antimicrobial utilization, microbiologic data, and clinical outcomes were compared across four year-long periods: pre-shortage, TZP shortage, cefepime shortage, and post-shortage. There were 7,668 episodes of antimicrobial prescribing for an indication of IAI during the study period. Cefepime use for IAI increased 190% during the TZP shortage; meanwhile ceftriaxone use increased by only 57%. There was no increase in in-house mortality, colonization with resistant organisms, or Clostridiodes difficile infection among patients treated with IAI during the shortage periods. Among a subset of cases randomly selected for review, Pseudomonas sp. was a rare cause of IAI, but anti-pseudomonal antibiotics were commonly prescribed empirically. We observed a large increase in cefepime utilization for IAI during a TZP shortage that was not warranted based on the observed frequency of identification of Pseudomonas sp. as the causative organism in IAI, suggesting a need to revisit national guideline recommendations.

Intra-abdominal infection in acute pancreatitis in eastern China: microbiological features and a prediction model

Background

This study aimed to investigate the microbiol distribution of intra-abdominal infection in patients with acute pancreatitis, and to develop a reliable prediction model to guide the use of antibiotics.

Methods

Inpatient with acute pancreatitis between January 2015 and June 2020 were enrolled in the study. Participants were divided into the intra-abdominal infection group and non-infection group. Isolated pathogens and antibiotic susceptibility were documented. Characteristics parameters, laboratory results, and outcomes were also compared. Least absolute shrinkage and selection operator (LASSO) regression model was used to select the risk factors associated with intra-abdominal infection in patients with acute pancreatitis. Logistic regression analysis, random forest model, and artificial neural network were also used to validate the performance of the selected predictors in intra-abdominal infection prediction. A novel nomogram based on selected predictors was established to provide individualized risk of developing intra-abdominal infection in patients with acute pancreatitis.

Results

A total amount of 711 participants were enrolled in the study, and of these, 182 (25.6%) had intra-abdominal infection. Of the 247 isolated pathogens, 45 (18.2%) were multidrug-resistant bacteria, and antibiotic susceptibility was lower than that of China Antimicrobial Surveillance Network 2020. The LASSO method identified 5 independent predictors [intra-abdominal pressure (IAP), acute physiology and chronic health evaluation II (APACHE II), computed tomography severity index (CTSI), the severity of pancreatitis, and intensive care unit (ICU) admission] of intra-abdominal infection, which were validated by three different models. The area under the curve was >0.95 for all 5 predictors. A clinically useful nomogram based on these predictors was successfully established.

Conclusions

Multidrug-resistant bacteria were quite common in intra-abdominal infection. IAP, APACHE II, CTSI, the severity of pancreatitis, and ICU admission were identified as risk factors and the new nomogram based on these could help clinicians estimate the risk of intra-abdominal infection and optimize antimicrobial prescription for acute pancreatitis patients.

Clinical Efficacy and Safety of Cefoperazone-Sulbactam in Treatment of Intra-Abdominal Infections: A Systematic Review and Meta-Analysis

Background: In this systematic review and meta-analysis, we aimed to assess the clinical efficacy and safety of cefoperazone-sulbactam against alternative antibiotics in the treatment of intra-abdominal infections. Methods: The PubMed, Cochrane, Web of Science, Ovid Medline, and CKNI databases were searched for relevant articles up to November 25, 2020. The primary outcome was clinical efficacy rate, and the secondary outcomes were microbiologic eradication rate, mortality rate, and adverse event (AE) risk. Results: Twelve studies involving 1,674 patients were included. Overall, the clinical efficacy rate of cefoperazone-sulbactam and comparators was 87.7% and 81.7%, respectively, and cefoperazone-sulbactam was associated with a higher clinical efficacy rate than that the comparator (odds ratio [OR] 1.98; 95% confidence interval [CI] 1.31-3.00; I² = 36%). Additionally, cefoperazone-sulbactam was associated with a lower clinical failure rate (OR 0.40; 95% CI 0.28-0.57; I² = 0) and a higher clinical cure rate (OR 1.54; 95% CI 1.17-2.03; I² = 0) than the comparators. Cefoperazone-sulbactam was associated with a higher microbiologic eradication rate than the comparator (OR 2.54; 95% CI 1.72-3.76; I² = 0). Finally, there was no significant difference between cefoperazone-sulbactam and the comparators in terms of mortality rate (OR 090; 95% CI 0.38-2.16; I² = 0) and AE risk (OR 1.07; 95% CI 0.74-1.55; I² = 0). Conclusions: The clinical efficacy and safety of cefoperazone-sulbactam were similar to those of alternative antibiotics in the treatment of intra-abdominal infections. Therefore, cefoperazone-sulbactam could be recommended as an effective and safe antibiotic for treating intra-abdominal infections.

Duration of post-operative antibiotic treatment in acute complicated appendicitis: systematic review and meta-analysis

BACKGROUND

Appendicitis is the most frequent aetiology of acute abdominal pain requiring surgical treatment, with an estimated lifetime risk between 7% and 8%. Antibiotics play a substantial role in treatment, and there is considerable debate regarding the duration of antibiotics in treating appendicitis.

METHODS

We searched multiple databases from inception until June 2019 for peer-reviewed studies that compared different durations of antibiotic treatment after appendicectomy for acute complicated appendicitis in adults. We dichotomized reported data into short- and extended-term antibiotic use and controlled for different definitional thresholds in the meta-analysis. We generated risk ratios using restricted maximum likelihood methods and mixed effects modelling for each outcome of interest.

RESULTS

Four observational studies involving 847 participants were included in the meta-analysis. For the primary outcomes of intra-abdominal infection, we did not find a statistically significant difference between extended- and short-term antibiotic strategies for intra-abdominal infection (Risk ratio 0.92, 95% confidence interval (CI) 0.49-1.74). Three randomized controlled trials involving 291 participants were included in a separate meta-analysis. We found that extended antibiotic usage was not associated with a statistically significant reduced risk for intra-abdominal infection (RR 0.52, 95% CI 0.21-1.29) or surgical site skin infection (RR 1.44, 95% CI 0.43-4.81).

CONCLUSION

This systematic review and meta-analysis found that extended post-operative antibiotic treatment may not be associated with a reduced risk of intra-abdominal infection; however, meta-analysis was significantly limited by heterogeneity between studies and underpowered trials. Further large randomized controlled trials are needed to confirm these findings.

Early Procalcitonin Assessment in the Emergency Department in Patients with Intra-Abdominal Infection: An Excess or a Need?

Background: Intra-abdominal infection (IAI) is a wide range of intra-abdominal disease. Management involves empirical therapy and source control. Procalcitonin (PCT) has been suggested to assist in defining individual infection status and delivering individualized therapy. The aim of this study was to investigate the effects on patient outcomes of an early procalcitonin (PCT) assessment (in the emergency department [ED]) in patients with IAI. Methods: This was a retrospective, mono-centric study evaluating consecutive patients admitted to the ED from 2015 to 2019 with diagnosis of IAI. According to whether there had been PCT determination in the ED, patients were divided into no ePCT determination (no-ePCT) and early PCT determination in the ED (ePCT). The primary endpoint was the intra-hospital mortality rate. Secondary endpoints were occurrence of major complications and length of hospital stay (LOS). The propensity score match (PSM) was generated using a logistic regression model on the baseline covariates considered to be potentially influencing the decision to determine PCT in the ED and confounding factors identified as significant at a preliminary statistical analysis with respect to in-hospital death. Results: A series of 3,429 patients were included. The ePCT group consisted to 768 (22.4%), whereas the no-ePCT group contained 2,661 patients (77.6%). When the PSM was matched to the two groups, no significant difference was observed. Considering patients with uncomplicated infections, the PCT determination was associated with a higher mortality rate. We found no significant differences regarding outcomes with the exception of LOS, which was slightly longer in the ePCT group. However, we observed a tendency toward a minor difference in the number of complications in the ePCT group, in particular a reduced rate of progression to sepsis. Conclusion: Early PCT determination could be irrelevant in IAIs. The PCT value may be cost-effective and possibly improve the prognosis in cIAIs. Further research is needed to understand the optimal use of PCT, including in combination with other emerging diagnostic tests.

Effects of a Paediatric Antimicrobial Stewardship Program on Antimicrobial Use and Quality of Prescriptions in Patients with Appendix-Related Intraabdominal Infections

The effectiveness of antimicrobial stewardship programs (ASP) in reducing antimicrobial use (AU) in children has been proved. Many interventions have been described suitable for different institution sizes, priorities, and patients, with surgical wards being one of the areas that may benefit the most. We aimed to describe the results on AU and length of stay (LOS) in a pre-post study during the three years before (2014–2016) and the three years after (2017–2019) implementation of an ASP based on postprescription review with feedback in children and adolescents admitted for appendix-related intraabdominal infections (AR-IAI) in a European Referral Paediatric University Hospital. In the postintervention period, the quality of prescriptions (QP) was also evaluated. Overall, 2021 AR-IAIs admissions were included. Global AU, measured both as days of therapy/100 patient days (DOT/100PD) and length of therapy (LOT), and global LOS remained unchanged in the postintervention period. Phlegmonous appendicitis LOS (p = 0.003) and LOT (p < 0.001) significantly decreased, but not those of other AR-IAI diagnoses. The use of piperacillin–tazobactam decreased by 96% (p = 0.044), with no rebound in the use of other Gram-negative broad-spectrum antimicrobials. A quasisignificant (p = 0.052) increase in QP was observed upon ASP implementation. Readmission and case fatality rates remained stable. ASP interventions were safe, and they reduced LOS and LOT of phlegmonous appendicitis and the use of selected broad-spectrum antimicrobials, while increasing QP in children with AR-IAI.

Is the Isolation of Pseudomonas aeruginosa Associated with Outcomes from Intra-Abdominal Infection? No, But the Receipt of an Empiric Anti-Pseudomonal Agent Is

Background: Pseudomonas aeruginosa is isolated at variable rates from intra-abdominal infections (IAI). Not all recommended empiric regimens for IAI include anti-Pseudomonas aeruginosa activity, for example, ceftriaxone and metronidazole. We hypothesized that within an adult population, Pseudomonas aeruginosa is a relatively rare isolate and has no association with mortality, and thus, empiric therapy with anti-Pseudomonas aeruginosa activity is not warranted. Patients and Methods: All IAI with positive cultures treated between 1997 and 2017 at a single institution were analyzed. This data set was divided into two cohorts, namely, those with cultures positive for Pseudomonas aeruginosa and those without. Demographics and in-hospital mortality were compared by Student t-test and χ² analysis. Predictors of isolation of Pseudomonas aeruginosa and in-hospital mortality were done by logistic regression (LR) analysis. Results: In total, 2,420 IAIs were identified, 104 (4.3%) with Pseudomonas aeruginosa and 2,316 (95.7%) without. Major demographic differences between patients with Pseudomonas aeruginosa and those without included a higher rate of health-care-associated infections (87/104, 83.7% vs. 621/2316, 26.8%; p = 0.02), a higher rate of intensive care unit (ICU)-acquired infections (23/104, 22.1% vs. 329/2316, 14.2%; p = 0.04) and a higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (17.7 ± 0.8 vs. 14.5 ± 0.2; p < 0.0001). There was an increased rate of Pseudomonas aeruginosa isolation with increasing APACHE II score. Independent predictors of isolation of Pseudomonas aeruginosa by LR included APACHE II score and days of hospitalization prior to diagnosis. Crude in-hospital mortality was similar between groups: Pseudomonas aeruginosa 14/104 (13.5%) and 276/2316 (11.9%), p = 0.79. After controlling for age, gender, APACHE II, prior transfusion, immunosuppression status, solid organ transplant status, healthcare-association, and days of hospitalization prior to diagnosis, the isolation of Pseudomonas aeruginosa was not associated with mortality. Conclusion: Pseudomonas aeruginosa is infrequently isolated and overall not associated with mortality. Nonetheless, there may be a population that merits empiric anti-Pseudomonas aeruginosa therapy: those with APACHE II ≥20 or a significant length of hospitalization prior to diagnosis.

Deresuscitation in Patients with Abdominal Sepsis Carries a Lower Mortality Rate and Less Organ Dysfunction than Conservative Fluid Management

Background: The relation between deresuscitative fluid management after the resuscitation phase and clinical outcome in patients with abdominal sepsis is not completely clear. The aim of this study was to assess the contribution of deresuscitative management to death and organ dysfunction in abdominal sepsis. Methods: Consecutive patients with abdominal sepsis requiring fluid resuscitation were included in this study. According to the fluid management given in the later stage of resuscitation, a conservative group and a deresuscitative fluid management group were compared. The primary outcome was in-hospital death, whereas secondary outcomes were categorized as organ dysfunction and other adverse events. Results: A total of 138 patients were enrolled in this study. Conservative fluid management was given to 47.8% of patients, whereas deresuscitative fluid management occurred in 52.2%. The deresuscitative strategy was associated with a markedly lower prevalence of new-onset acute kidney injury and a decrease in the duration of continuous renal replacement therapy (CRRT). There was a greater risk of needing new-onset intubation and the mechanical ventilation duration in the conservative group than in the deresuscitative group. However, the deresuscitative group did not differ from the conservative group with respect to open abdomen and intra-abdominal hypertension or new-onset abdominal compartment syndrome. The conservative treatment was associated with prolonged stays as well as a higher in-hospital mortality rate. A multivariable logistic regression model showed that deresuscitative fluid management imparts a protective effect against in-hospital death (odds ratio 4.343; 95% confidence interva1 1.466-12.866; p = 0.008), whereas septic shock, source control failure, and CRRT duration were associated with a higher mortality rate. Conclusions: Fluid balance achieved using deresuscitative treatment is correlated with better outcomes in patients with abdominal sepsis, indicating that this treatment may be useful as a therapeutic strategy.

The uroS and yifB Genes Conserved among Tetrapyrrole Synthesizing-Deficient Bacteroidales Are Involved in Bacteroides fragilis Heme Assimilation and Survival in Experimental Intra-abdominal Infection and Intestinal Colonization

The human intestinal anaerobic commensal and opportunistic pathogen Bacteroides fragilis does not synthesize the tetrapyrrole protoporphyrin IX in order to form heme that is required for growth stimulation and survival in vivo Consequently, B. fragilis acquires essential heme from host tissues during extraintestinal infection. The absence of several genes necessary for de novo heme biosynthesis is a common characteristic of many anaerobic bacteria; however, the uroS gene, encoding a uroporphyrinogen III synthase for an early step of heme biosynthesis, is conserved among the heme-requiring Bacteroidales that inhabit the mammalian gastrointestinal tract. In this study, we show that the ability of B. fragilis to utilize heme or protoporphyrin IX for growth was greatly reduced in a ΔuroS mutant. This growth defect appears to be linked to the suppression of reverse chelatase and ferrochelatase activities in the absence of uroS In addition, this ΔuroS suppressive effect was enhanced by the deletion of the yifB gene, which encodes an Mg²⁺-chelatase protein belonging to the ATPases associated with various cellular activities (AAA⁺) superfamily of proteins. Furthermore, the ΔuroS mutant and the ΔuroS ΔyifB double mutant had a severe survival defect compared to the parent strain in competitive infection assays using animal models of intra-abdominal infection and intestinal colonization. This shows that the presence of the uroS and yifB genes in B. fragilis seems to be linked to pathophysiological and nutritional competitive fitness for survival in host tissues. Genetic complementation studies and enzyme kinetics assays indicate that B. fragilis UroS is functionally different from canonical bacterial UroS proteins. Taken together, these findings show that heme assimilation and metabolism in the anaerobe B. fragilis have diverged from those of aerobic and facultative anaerobic pathogenic bacteria.

Analysis of Susceptibilities of Carbapenem Resistant Enterobacterales to Colistin in Intra-Abdominal, Respiratory and Urinary Tract Infections from 2015 to 2017

Purpose

To evaluate the susceptibility rates of carbapenem-resistant (CR)-Enterobacterales strains from Chinese intra-abdominal infections (IAI), respiratory tract infections (RTI) and urinary tract infections (UTI) between 2015 and 2017 to colistin.

Methods

In total, 7138 Enterobacterales including 1074 CR-Enterobacterales strains were isolated from IAI+UTI+RTI samples and collected in 21 hospitals across 7 regions of China. Antimicrobial susceptibilities were determined at a central laboratory using CLSI broth microdilution and interpretive standards.

Results

From 2015 to 2017, E. coli (51.4%) and K. pneumoniae (30.0%) accounted for the majority of Enterobacterales isolated from IAIs, UTIs and RTIs. The percentage of CR strains within the species was highest for S. marcescens (27.9%), followed by K. pneumoniae (24.8%), P. mirabilis (22.6), K. oxytoca (19.5%), E. cloacae (17.7%), C. freundii (12.5%), K. aerogenes (11.0%) and lowest for E. coli (6.9%). Colistin susceptibilities were generally higher in CS than in CR isolates and were 83.5% for CR-E. coli, 88.6% for CR-K. pneumoniae, 79.2% for CR-E. cloacae and 87.5% for CR-K. aerogenes. For IAI and UTI isolates in particular, CR-E. coli and CR-K. pneumoniae showed a trend of decreasing susceptibility, which was especially noted for CR-E. coli in UTI isolates, and for both organisms in IAI isolates susceptibility dropped markedly in 2017.

Conclusion

Colistin was a last resort antibiotics for empirical CR-Enterobacterales treatments, since especially the percentage of CR-K. pneumoniae was 30.0% of all IAI, UTI and RTI isolates, with an incidence of 24.8% CR strains, of which 88.6% were susceptible to colistin. Also other analyzed CR-Enterobacterales showed colistin susceptibilities of ≥80.0%. However, resistance rates of IAI derived CR-K. pneumoniae and CR-E. coli, and CR-K. pneumoniae UTI isolates to colistin increased between 2015 and 2017, which should further be closely monitored.

Global Perspectives in Controversies Related to the Management of Intra-Abdominal Infections

Background: Intra-abdominal infections (IAI) remain a substantial cause of worldwide morbidity, mortality, and healthcare cost burden. The World Surgical Infection Society (WSIS) was organized to help improve global outcomes from surgical infections. An initial project for the WSIS was to assess how surgeons treat common IAI in their regions. Methods: A 10-item questionnaire was distributed to members of four surgical societies dedicated to the study of surgical infections. Questions were related to common treatment decisions in the management of IAI, with the intention of identifying differences and potential controversies in patient care. Responses were analyzed by comparing percentages with 95% confidence intervals. Results: Globally, management was relatively similar for peritoneal irrigation (most commonly with saline or other crystalloid: China, 83.2% ± 5.8%; North America, 93.2% ± 6.4%; Europe, 85.7% ± 25.9%; and Latin America, 71.8% ± 6.9%). More varied responses were seen for the management of specific disease states; for instance, for cholangitis, endoscopic retrograde cholangiopancreatic interventions were more common in North America (83.1% ± 9.6%) and less common in China (28.1% ± 7.0%). For appendiceal abscesses, percutaneous drainage and antibiotic treatment was most common in North America (93.2% ± 6.4%) and least common in Latin America (19.6% ± 6.1%). Additionally, the management of fascial and wound closures were different by region. Vacuum-assisted wound closure after fascial closure was utilized commonly in North America (32.2% ± 11.9%), Europe (28.6% ± 33.5%), and Latin America (27.6% ± 6.9%), however, was less commonly utilized in China (9.9% ± 4.4%), where there was higher rate of primary skin closure (85.7% ± 5.4%). Conclusion: Through its partnership with other surgical infection societies, the WSIS aims to develop evidence-based guidelines for more consistent pattern of IAI management globally. Delving further into why their practices differ may help improve worldwide outcomes.

Systematic Review and Meta-Analysis of the Efficacy of Appropriate Empiric Anti-Enterococcal Therapy for Intra-Abdominal Infection

Background: Delayed treatment of seriously infected patients results in increased mortality. However, antimicrobial therapy for the initial 24 to 48 hours is mostly empirically provided, without evidence regarding the causative pathogen. Whether empiric anti-enterococcal therapy should be administered to treat intra-abdominal infection (IAI) before obtaining culture results remains unknown. We performed a meta-analysis to explore the effects of empiric enterococci covered antibiotic therapy in IAI and the risk factors for enterococcal infection in IAI. Methods: We searched multiple databases systematically and included 23 randomized controlled trials (RCTs) and 13 observational studies. The quality of included studies was assessed, and the reporting bias was evaluated. Meta-analysis was performed using random effects or fixed effects models according to the heterogeneity. The risk ratio (RR), odds ratio (OR), and 95% confidence interval (CI) were calculated. Results: Enterococci-covered antibiotic regimens provided no improvement in treatment success compared with control regimens (RR, 0.99; 95% CI, 0.97-1.00; p = 0.15), with similar mortality and adverse effects in both arms. Basic characteristic analysis revealed that most of the enrolled patients with IAI in RCTs were young, lower risk community-acquired intra-abdominal infection (CA-IAI) patients with a relatively low APACHE II score. Interestingly, risk factor screening revealed that malignancy, corticosteroid use, operation, any antibiotic treatment, admission to intensive care unit (ICU), and indwelling urinary catheter could predispose the patients with IAI to a substantially higher risk of enterococcal infection. "Hospital acquired" itself was a risk factor (OR, 2.81; 95% CI, 2.34-3.39; p < 0.001). Conclusion: It is unnecessary to use additional agents empirically to specifically provide anti-enterococcal coverage for the management of CA-IAI in lower risk patients without evidence of causative pathogen, and risk factors can increase the risk of enterococcal infection. Thus, there is a rationale for providing empiric anti-enterococcal coverage for severely ill patients with CA-IAI with high risk factors and patients with hospital-acquired intra-abdominal infection (HA-IAI).

Temporary Abdominal Closure Is Associated with Increased Risk for Fungal Intra-Abdominal Infections in Trauma Patients

Background: Fungal infections are associated with increased morbidity and death. Few studies have examined risk factors associated with post-operative fungal intra-abdominal infections (FIAIs) in trauma patients after exploratory laparotomy. In this study, we evaluated potential risk factors for acquiring post-operative FIAIs and their impact on clinical outcomes. Methods: This was a retrospective analysis of trauma patients admitted from 2005 to 2018 who underwent exploratory laparotomy and subsequently had development of intra-abdominal infection (IAI). Demographics, comorbidities, culture data, antimicrobial usage, Injury Severity Scores (ISS), and clinical outcomes were abstracted. All post-operative IAIs were evaluated and stratified as either bacterial, fungal, combined, and with or without colonization. All groups were compared. Risk factors for the development of post-operative IAI and clinical outcomes were analyzed by Student t test and chi-square test. Multi-variable logistic regression was used to determine independent predictors of post-operative FIAIs. Results: There were 1675 patients identified as having undergone exploratory laparotomy in the setting of traumatic injury, 161 of whom were suspected of having IAI. A total of 105 (6.2%) patients had a diagnosis of IAI. Of these patients, 40 (38%) received a diagnosis of FIAI. The most common fungal pathogens were unspeciated yeast (48.3%), followed by Candida albicans (42.7%), C. glabrata (4.5%), C. dubliniensis (2.25%), and C. tropicalis (2.25%). There were no significant differences in demographics, comorbidities, and percentage of gastric perforations between FIAI and bacterial IAI (BIAI) groups. Patients with FIAIs, however, had a 75% temporary abdominal closure (TAC) rate compared with 51% in BIAIs (p = 0.01). The FIAI group had higher ISS (27 vs. 22, p = 0.03), longer hospital days (34 vs. 25, p = 0.02), and longer intensive care unit (ICU) days (17 vs. 9, p = 0.006) when compared with BIAI. The FIAI group also had a five-fold greater mortality rate. Logistic regression identified TAC as an independent risk factor for the development of post-operative FIAIs (odds ratio [OR] 6.16, confidence interval [CI] 1.14-28.0, p = 0.02). Conclusions: An FIAI after exploratory laparotomy was associated with greater morbidity and death. A TAC was associated independently with increased risk of FIAI after exploratory laparotomy in the setting of traumatic injury. Clinicians should suspect fungal infections in trauma patients in whom post-operative IAI develops after undergoing exploratory laparotomy using TAC techniques.

Carbapenem Treatment and Outcomes Among Patients With Culture-Positive Complicated Intra-abdominal Infections in US Hospitals: A Retrospective Cohort Study

Background

Carbapenems are a frequent firstline therapy in complicated intra-abdominal infections (cIAIs). We examined the microbiology, epidemiology, and outcomes among patients hospitalized in the United States with culture-positive cIAIs in the context of their exposure to empiric carbapenem treatment (ECT).

Methods

We performed a multicenter retrospective cohort study of Premier database of ~180 hospitals, 2013–2017. Using an International Classification of Diseases (ICD)-9/10-based algorithm, we identified all culture-positive adult patients hospitalized with cIAI and examined their microbiology, epidemiology, and outcomes.

Results

Among 4453 patients with cIAIs, 3771 (84.7%) had a gram-negative (GN) and 1782 (40.0%) a gram-positive organism; 1185 (26.6%) received ECT. Compared with those on non-ECT, patients on ECT were less frequently admitted from home (82.5% vs 86.0%) or emergently (76.0% vs 81.4%; P < .05 for each); E. coli were less frequent, whereas P. aeruginosa and Enterococcus spp. were more prevalent and resistance to third-generation cephalosporins (C3R; 10.1% vs 5.1%; P < .001) and carbapenems (CR; 3.6% vs 1.2%; P < .001) was more common. In adjusted analyses, ECT was associated with no rise in mortality, shorter postinfection length of stay (–0.59 days; 95% confidence interval [CI], –1.15 to –0.03), but higher postinfection costs ($3844; 95% CI, $1921 to $5767) and risk of Clostridioides difficile (odds ratio, 2.15; 95% CI, 1.02 to 4.50).

Conclusions

Among patients hospitalized with cIAI, the majority were gram-negative. Despite a 10% prevalence of C3R, fully one-quarter of all empiric regimens contained a carbapenem. ECT was a marker for slightly lower postinfection length of stay, but higher costs and risk of hospital complications.

Is fixed short-course antimicrobial therapy justified for patients who are critically ill with intra-abdominal infections?

A long-course antibiotic therapy increases the risk of antibiotic resistance. A 7- to 14-day duration of therapy has been traditionally adopted in patients with intra-abdominal infections (IAIs). Prophylactic antibiotic use is warranted in uncomplicated IAIs, in which the infection involves a single organ, and the source of the infection is completely eradicated by a surgical procedure. A large, randomized clinical trial of the treatment of complicated IAIs recently demonstrated that a fixed 4-day course of antibiotic therapy was as effective as a long-course therapy in patients who underwent adequate source control. Considering the poor prognosis and lack of clear evidence available for shortening the duration of antibiotic therapy in patients who are critically ill or those with ongoing signs of sepsis, the duration of therapy for complicated IAIs should be individually determined according to the clinical course. Limiting therapy to no more than 7 days seems to be warranted in patients who are critically ill with a good clinical response.

Coagulative biomarkers on admission to the ICU predict acute kidney injury and mortality in patients with septic shock caused by intra-abdominal infection

Purpose

Sepsis-associated coagulopathy (SAC) contributes to the development of multiple organ failure (MOF) and increasing mortality. The present study was conducted to investigate whether coagulative biomarkers on admission to the intensive care unit (ICU) can predict acute kidney injury (AKI) and mortality in patients with septic shock caused by intra-abdominal infection (IAI).

Patients and methods

An observational retrospective study was conducted in the surgical ICU. We studied patients who met the criteria of septic shock (Sepsis-3) caused by IAI between January 1, 2013, and December 31, 2016. By adjusting for baseline characteristics, multivariate regression analyses were employed to identify independent risk factors for predicting AKI and mortality.

Results

Of the 138 enrolled patients, 65 patients developed AKI. The patients who developed AKI exhibited a dramatically higher Sequential Organ Failure Assessment (SOFA) score (median, 12), Acute Physiology and Chronic Health Evaluation (APACHE) II score (median, 27.5) and mortality rate. In both models, we found that activated partial thromboplastin time (APTT) (odds ratio (OR)=1.074, 95% confidence interval (CI) 1.030-1.120, p=0.001), prothrombin time (PT) (OR=1.162, 95% CI 1.037-1.302, p=0.010) and D-dimer level (OR=1.098, 95% CI 1.002-1.202, p=0.045) on admission to the ICU were significant risk factors for AKI. Moreover, Cox regression analysis showed that prolonged APTT (OR=1.065, 95% CI 1.025-1.107, p=0.001) was independently associated with high mortality.

Conclusion

In patients with septic shock caused by IAI, APTT, PT and D-dimer level on admission to the ICU were significantly associated with AKI. Furthermore, APTT was an independent predictor of 30-day mortality.

Artificial neural networks accurately predict intra-abdominal infection in moderately severe and severe acute pancreatitis

OBJECTIVE

The aim of this study was to evaluate the efficacy of artificial neural networks (ANN) in predicting intra-abdominal infection in moderately severe (MASP) and severe acute pancreatitis (SAP) compared with that of a logistic regression model (LRM).

METHODS

Patients suffering from MSAP or SAP from July 2014 to June 2017 in three affiliated hospitals of the Army Medical University in Chongqing, China, were enrolled in this study. A univariate analysis was used to determine the different parameters between patients with and without intra-abdominal infection. Subsequently, these parameters were used to build LRM and ANN.

RESULTS

Altogether 263 patients with MSAP or SAP were enrolled in this retrospective study. A total of 16 parameters that differed between patients with and without intra-abdominal infection were used to construct both models. The sensitivity of ANN and LRM was 80.99% (95% confidence interval [CI] 72.63-87.33) and 70.25% (95% CI 61.15-78.04), respectively (P > 0.05), whereas the specificity was 89.44% (95% CI 82.89-93.77) and 77.46% (95% CI 69.54-83.87), respectively (P < 0.05). ANN predicted the risk of intra-abdominal infection better than LRM (area under the receiver operating characteristic curve: 0.923 [0.883-0.952] vs 0.802 [0.749-0.849], P < 0.001).

CONCLUSIONS

ANN accurately predicted intra-abdominal infection in MSAP and SAP and is an ideal tool for predicting intra-abdominal infection in such patients. Coagulation parameters played an important role in such prediction.

Antibiotic Resistance in Community-Acquired Intra-Abdominal Infections: Diabetes Mellitus as a Risk Factor

Background: Antimicrobial drug resistance in community-acquired (CA) infections is a growing problem. Knowing the local epidemiology is essential to design empirical antibiotic therapy. Therefore, we conducted this study to evaluate the resistance patterns of microorganisms isolated from surgical samples of community-acquired intra-abdominal infections (IAIs) and to determine the factors associated with resistance. Methods: We analyzed retrospectively the records of patients treated from January 2015 to June 2017 who had IAIs with positives aerobic cultures performed in the first 72 hours after admission. Surgical site infections, abdominal wall procedures, peritoneal dialysis catheters, and patients with admissions in the prior month were excluded. To identify the factors associated with resistance, we considered the resistance to the regimen recommended at our institution, ampicillin/sulbactam (AMS) plus ciprofloxacin (CIP). Results: There were 119 patients with 133 isolates, 59% women, and mean age 54 years. The main sources of infection were appendicitis (38%) and cholecystitis (20%), with 64 patients presenting a complicated IAI (cIAI), defined by the presence of peritonitis (55%). Resistance in Enterobacteriaceae was AMS 32% (6.4% intermediate resistance), CIP 31%, cefotaxime 9%, piperacillin/tazobactam (PTZ) 3%, trimethoprim/sulfamethoxazole 32%, gentamicin 9.5%, and amikacin 2%. Considering all patients, resistance to AMS + CIP was 16.8%. Factors associated with resistant to this regimen was, by univariable and multivariable analysis, the presence of diabetes mellitus (odds ratio [OR] 3.6; 95% confidence interval [CI] 1.1-11.6; p = 0.03). Female gender (OR 2.7; CI 0.9-8.4; p = 0.08) and complicated IAI (OR 2.0; CI 0.7-5.4; p = 0.17) were associated with resistance but did not reach statistical significance. Conclusion: High resistance to CIP and AMS was observed. Although the combination of AMS + CIP offers coverage for 84% of patients, PTZ should be considered as an option for patients with severe infections or diabetes mellitus. Finding factors associated with antibiotic resistance could help to select empirical therapy for CA IAIs better.

Antimicrobial susceptibility changes of Escherichia coli and Klebsiella pneumoniae intra-abdominal infection isolate-derived pathogens from Chinese intra-abdominal infections from 2011 to 2015

Background

To explore the susceptibility trends of antimicrobials and resistance increase to antibiotics of Enterobacteriaceae isolated from patients in China with intra-abdominal infections (IAI) from 2011 to 2015.

Methods

MIC₉₀ and MIC₅₀ values of 12 commonly used antibiotics from Escherichia coli and Klebsiella pneumoniae isolated from IAI samples were determined.

Results

A total of 8,477 Gram-negative bacterial pathogens were collected from 21 medical centers in China. The majority of IAI isolate-derived pathogens were E. coli (3,854, 45.5%) and K. pneumoniae (1,670, 19.7%) of which 1,990 (23.5%) were consecutively collected from community acquired (CA) and 6,186 (73.0%) from hospital acquired (HA) IAIs. The drugs with the highest efficacy against E. coli and K. pneumoniae isolates derived from IAI samples were imipenem, ertapenem, amikacin and piperacillin-tazobactam. MIC₉₀ values for piperacillin-tazobactam were 64 µg/mL in 2015 with fluctuations from 16–64 µg/mL through the years for E. coli, but were stable at ≥64 µg/mL from 2011 to 2015 for K. pneumoniae isolates. Susceptibilities to ertapenem, imipenem and amikacin were high for E. coli isolates throughout the study, but K. pneumoniae isolated from abscesses, colon and peritoneal fluid collected from medical and surgical ICUs showed an increasing trend of carbapenem resistance in 2015.

Conclusion

In 2015 there was a trend of enhanced carbapenem resistance, particularly for K. pneumoniae isolated from IAI samples obtained from patients in ICUs.