Hospital-acquired Intra-abdominal Infections Research Articles

Clinical and Microbiological Study of Intra-Abdominal Infections in a Tertiary Care Hospital

Intra-abdominal infections (IAIs) are one of the important contributors to sepsis in intensive care units. The emergence of antibiotic resistance and the diversification of etiological agents make it challenging to determine the optimal empirical therapy. This study attempts to know the etiological agents, their antibiotic susceptibility patterns, and the risk factors associated with IAIs in different settings. This prospective cross-sectional study was conducted in a tertiary care facility from January 2023 to June 2023. Adult and paediatric patients having primary IAI or developed infections during their hospital stay were included in this study. Specimen like peritoneal swabs or fluid from intra-abdominal drains placed for more than 24 hours were excluded. Matrix-assisted Laser Desorption/Ionization Time-Of-Flight was used to identify the etiological agents. Vitek®2 system was used to perform the antimicrobial susceptibility. Associated risk factors were documented. A total of 86 cases were analysed. The majority of the patients had complicated IAIs (95.3%), and 65.12 % acquired the infection in the community (CA-IAI). The vast number of cases presented with intra-abdominal abscesses (46.5%). Diabetes and hepatic disorders were the frequent underlying comorbid conditions associated with CA-IAIs. Prolonged hospital stay and the presence of concomitant conditions like malignancy and chronic renal failure significantly influenced the occurrence of hospital-acquired infections (HA-IAIs). E. coli was the frequently isolated Gram-negative pathogen both in the community and hospital settings. Whereas among Gram-positives, Enterococcus predominated and was commonly isolated from HA-IAIs. Enterobacterales were highly susceptible to meropenem and piperacillin-tazobactam. E. coli and Klebsiella were the frequent extended-spectrum beta-lactamase producers and showed the least susceptibility towards cephalosporins and fluoroquinolones. Multidrug-resistant organisms (MDROs) (p=.013), including carbapenem-resistant strains (p=.048), were significantly isolated from hospital-acquired IAIs. The high prevalence of IAIs with MDROs in hospital settings emphasizes the importance of developing hospital-based antibiotic policy, infection control measures, and judicious use of antibiotics.

Next-generation microbiological testing in intraabdominal infections with PCR technology

PurposeIntraabdominal infections (IAI) are increasing worldwide and are a major contributor to morbidity and mortality. Among IAI, the number of multi-drug resistant organisms (MDRO) is increasing globally. We tested the Unyvero A50® for intraabdominal infections, compared the detected microorganisms and antibiotic resistance, and compared the results with those of routine microbiology.MethodsWe prospectively compared samples obtained from surgical patients using PCR-based Unyvero IAI cartridges against routine microbiology for the detection of microorganisms. Additionally, we identified clinical parameters that correlated with the microbiological findings. Data were analyzed using the t-test and Mann–Whitney U test.ResultsSixty-two samples were analyzed. The PCR system identified more microorganisms, mostly Bacteroides species, Escherichia coli, and Enterococcus spp. For bacterial resistance, the PCR system results were fully concordant with those of routine microbiology, resulting in a sensitivity, specificity, and positive and negative predictive value (PPV, NPV) of 100%. The sensitivity, specificity, PPV, and NPV for the detection of microorganisms were 74%, 58%, 60%, and 72%, respectively. CRP levels were significantly higher in patients with detectable microorganisms. We identified more microorganisms and bacterial resistance in hospital-acquired intra-abdominal infections by using the PCR system.DiscussionIAI warrants early identification of the microorganisms involved and their resistance to allow for adequate antibiotic therapy. PCR systems enable physicians to rapidly adjust their antibiotic treatment. Conventional microbiological culture and testing remain essential for determining the minimal growth inhibition concentrations for antibiotic therapy.

Comparative phenotypic and genotypic analysis of community-acquired and hospital-acquired intra-abdominal infections among liver transplanted patients.

During liver transplantation, both hospital-acquired (HA) and community-acquired (CA) intra-abdominal infections (IAIs) are involved causing life-threatening diseases. Therefore, comparative studies of aerobic and facultative anaerobic HA-IAIs and CA-IAIs after liver transplantation surgery are necessary. The species of detected isolates (310) from intra-abdominal fluid were identified and classified into hospital-acquired intra-abdominal infections (HA-IAIs) and community-acquired intra-abdominal infections (CA-IAIs). Klebsiella pneumoniae, Escherichia coli, Pseudomonas aeruginosa, and Acinetobacter baumannii were the most commonly detected species. The resistant phenotypes were commonly detected among the HA-IAIs; however, the virulent phenotypes were the predominant strains of CA-IAIs. Regrettably, the resistance profiles were shocking, indicating the inefficacy of monotherapy in treating these isolates. Therefore, we confirmed the use of empirical combination therapies of amikacin and meropenem for treating all IAIs (FICI≤0.5). Unfortunately, the high diversity and low clonality of all identified HA and CA-IAIs were announced with D-value in the range of 0.992-1. This diversity proves that there are infinite numbers of infection sources inside and outside healthcare centers.

Risk factors of acute respiratory distress syndrome in sepsis caused by intra-abdominal infections: A retrospective study

BackgroundIntra-abdominal infections are frequently associated with acute respiratory distress syndrome, which significantly affects patient prognosis. However, little is known about the specific risk factors of acute respiratory distress syndrome in sepsis caused by intra-abdominal infections. MethodsThis retrospective study included adult patients with intra-abdominal sepsis admitted to the intensive care unit of a tertiary teaching hospital in China between June 2017 and June 2022. Patients were categorized based on the presence or absence of acute respiratory distress syndrome. Data, including vital signs, laboratory values, and severity scores collected within 24 hours of sepsis diagnosis, as well as outcomes within 90 days, were analyzed. Multivariable logistic regression was used to identify independent risk factors associated with acute respiratory distress syndrome. ResultsA total of 738 patients were included, of whom 218 (29.5%) developed acute respiratory distress syndrome. Patients with acute respiratory distress syndrome were younger, had a higher body mass index and disease severity scores, and exhibited higher proportions of septic shock and hospital-acquired intra-abdominal infections. The mortalities in the intensive care unit and at 28 and 90 days were higher in the acute respiratory distress syndrome group. In the multivariate logistic regression model, age under 65 years (odds ratio [95% confidence interval]: 1.571 [1.093–2.259]), elevated body mass index (2.070 [1.382–3.101] for overweight, 6.994 [3.207–15.255]) for obesity, septic shock (2.043 [1.400–2.980]), procalcitonin (1.009 [1.004–1.015]), hospital-acquired intra-abdominal infections (2.528[1.373–4.657]), and source of intra-abdominal infections (2.170 [1.140–4.128] for biliary tract infection, 0.443 [0.217–0.904] for gastroduodenal perforation) were independently associated with acute respiratory distress syndrome. ConclusionIn patients with intra-abdominal sepsis, age under 65 years, higher body mass index and procalcitonin, septic shock, hospital-acquired intra-abdominal infections, and biliary tract infection were risk factors for acute respiratory distress syndrome.

Outcome of community- versus hospital-acquired intra-abdominal infections in intensive care unit: a retrospective study

BackgroundTo compare patients hospitalised in the intensive care unit (ICU) after surgery for community-acquired intra-abdominal infection (CA-IAI) and hospital-acquired intra-abdominal infection (HA-IAI) in terms of mortality, severity and complications.MethodsRetrospective study including all patients admitted to 2 ICUs within 48 h of undergoing surgery for peritonitis.ResultsTwo hundred twenty-six patients were enrolled during the study period. Patients with CA-IAI had an increased 28-day mortality rate compared to those with HA-IAI (30% vs 15%, respectively (p = 0.009)). At 90 days, the mortality rates were 36.7 and 37.5% in the CA-IAI group and HA-IAI group, respectively, with a similar APACHE II score on admission (median: 21 [15–25] vs. 21 [15–24] respectively, p = 0.63). The patients with HA-IAI had prolonged ICU and hospital stays (median: 17 [7–36] vs. 6[3–12] days, p < 0.001 and 41 [24–66] vs. 17 [7–32] days, p = 0.001), and experienced more complications (reoperation and reintubation) than those with CA-IAI.ConclusionCA-IAI group had higher 28-day mortality rate than HA-IAI group. Mortality was similar at 90 days but those with HA-IAI had a prolonged ICU and hospital stay. In addition, they developed more complications.

Antimicrobial susceptibilities of specific syndromes created with organ-specific weighted incidence antibiograms (OSWIA) in patients with intra-abdominal infections

BackgroundThe aim was to evaluate the value of organ-specific weighted incidence antibiogram (OSWIA) percentages for bacterial susceptibilities of Gram-negative bacteria (GNB) collected from intra-abdominal infections (IAIs) during SMART 2010–2014.MethodsWe retrospectively calculated the OSWIA percentages that would have been adequately covered by 12 common antimicrobials based on the bacterial compositions found in the appendix, peritoneum, colon, liver, gall bladder and pancreas.ResultsThe ESBL positive rates were 65.7% for Escherichia coli, 36.2% for Klebsiella pneumoniae, 42.9% for Proteus mirabilis and 33.1% for Klebsiella oxytoca. Escherichia coli were mainly found in the appendix (76.8%), but less so in the liver (32.4%). Klebsiella pneumoniae constituted 45.2% of the total liver pathogenic bacteria and 15.2–20.8% were found in 4 other organs, except the colon and appendix (< 10%). The percentages of Pseudomonas aeruginosa infections were higher in the gall bladder, intra-abdominal abscesses, pancreas and colon (10.2–13.2%) and least (5.4%) in the appendix. The susceptibilities of hospital acquired (HA) and community acquired (CA) IAI isolates from appendix, gall bladder and liver showed ≥80% susceptibilities to amikacin (AMK), imipenem (IPM), piperacillin-tazobactam (TZP) and ertapenem (ETP), while the susceptibility of isolates in abscesses and peritoneal fluid showed ≥80% susceptibility only to amikacin (AMK) and imipenem (IPM). In colon CA IAI isolates susceptibilities did not reach 80% for AMK and ETP, and in pancreatic IAIs susceptibilities of HA GNBs did not reach 80% to AMK, TZP and ETP, and CA GNBs to IMP and ETP. In addition, besides circa 80% susceptibility of HA and CA IAI isolates from appendix to cefoxitin (FOX), IAI isolates from all other organs had susceptibilities between 7.6 and 67.9% to all cephalosporins tested, 28.3–75.2% to fluoroquinolones and 7.6–51.0% to ampicillin-sulbactam (SAM), whether they were obtained from CA or HA infections.ConclusionThe calculated OSWIA susceptibilities were specific for different organs in abdominal infections.

Does microbial resistance profile change in community-based intra-abdominal infections? Evaluation of the culture results of patients with appendicitis.

Tartar T, Sağmak-Tartar A, Saraç M, Bakal Ü, Akbulut A, Kazez A. Does microbial resistance profile change in community-based intra-abdominal infections? Evaluation of the culture results of patients with appendicitis. Turk J Pediatr 2018; 60: 520-526. Most common origin of intra-abdominal infections in children is appendicitis. Microorganisms responsible for community-based and hospital-acquired intra-abdominal infections vary. The aim of this study was to evaluate microbial culture outcomes and antibiotic susceptibilities of these microorganisms in samples obtained intraoperatively from pediatric patients with appendicitis, and to define the infectious microorganisms responsible for the community-based intra-abdominal infections in our region, and their antibiotic susceptibilities. This study included 231 patients between 0 and 16 years of age, operated on due to appendicitis between 2014 and 2017. Appendicular tissues were sampled intraoperatively. Antibiogram was studied in case of reproduction in tissue culture. Forms included information on the age and gender of the patients, intra-abdominal event, bacterial growth in microbial culture and antibiogram, antibiotic switch during follow-up, duration of the treatment, complications and outcomes were recorded. No microbial growth was observed following inoculation of the samples obtained from appendiceal tissue of 24.7% patients, whereas growth was positive in 75.3%. Gram negative bacteria were isolated in 94.3% of the patients, whereas gram positive bacteria was isolated in 5.7%. Polymicrobial growth was observed in 2.2% of the patients. E. coli in 79.9%, P. aeruginosa in 5.2%, Enterobacter cloacae in 3.4%, Coagulase-negative staphylococci in 3.4%, Klebsiella spp. in 1.7%, Citrobacter spp. in 1.7%, Enterococcus spp. in 1.7%, Comamonas testosteroni in 1.2% of patients produced. ESBL positivity is present in 51 (36.7%) of 139 E. coli strains reproducing in appendiceal tissue culture. ESBL was positivity detected in one of the reproduced 3 Klebsiella spp. strains. In E. coli, ciprofloxacin resistance as 20.86%, ampicillin-sulbactam resistance as 83.45%, and co-trimoxazole resistance as 41% were found. Our study clearly demonstrates that the resistance profile varies in community-based intra-abdominal infections. Empirical treatment protocols should be revised in especially the patients admitted with septic presentation and where the source control is not possible.

Antimicrobial Susceptibilities of Aerobic and Facultative Gram-Negative Bacilli from Intra-abdominal Infections in Patients from Seven Regions in China in 2012 and 2013.

To evaluate the antimicrobial susceptibility of Gram-negative bacilli that caused hospital-acquired and community-acquired intra-abdominal infections (IAIs) in China between 2012 and 2013, we determined the susceptibilities to 12 antimicrobials and the extended-spectrum β-lactamase (ESBL) statuses of 3,540 IAI isolates from seven geographic areas in China in a central laboratory using CLSI broth microdilution and interpretive standards. Most infections were caused by Escherichia coli (46.3%) and Klebsiella pneumoniae (19.7%). Rates of ESBL-producing E. coli (P = 0.031), K. pneumoniae (P = 0.017), and Proteus mirabilis (P = 0.004) were higher in hospital-acquired IAIs than in community-acquired IAIs. Susceptibilities of enterobacteriaceae to ertapenem, amikacin, piperacillin-tazobactam, and imipenem were 71.3% to 100%, 81.3% to 100%, 64.7% to 100%, and 83.1% to 100%, respectively, but imipenem was ineffective against P. mirabilis (<20%). Although most ESBL-positive hospital-acquired isolates were resistant to third- and fourth-generation cephalosporins, the majority were susceptible to cefoxitin (47.9% to 83.9%). Susceptibilities of ESBL-positive isolates to ampicillin-sulbactam (<10%) were low, whereas susceptibilities to ciprofloxacin (0% to 54.6%) and levofloxacin (0% to 63.6%) varied substantially. The prevalences of cephalosporin-susceptible E. coli and K. pneumoniae were higher in the northeastern and southern regions than in the central and eastern regions, reflecting the ESBL-positive rates in these areas, and were lowest in the Jiangsu-Zhejiang (Jiang-Zhe) area where the rates of carbapenem resistance were also highest. Ertapenem, amikacin, piperacillin-tazobactam, and imipenem are the most efficacious antibiotics for treating IAIs in China, especially those caused by E. coli or K. pneumoniae. Resistance to cephalosporins and carbapenems is more common in the Jiang-Zhe area than in other regions in China.

A practical look at the clinical usefulness of the beta-lactam/beta-lactamase inhibitor combinations.

To aid clinicians in developing an approach to the use of intravenous beta-lactam/beta-lactamase inhibitors on a patient-specific basis. To achieve this, the pharmacology, in vitro activity, and clinical use of the intravenous beta-lactam/beta-lactamase inhibitor combinations in the treatment of selected infections seen in hospitalized patients are discussed. An English-language literature search using MEDLINE (1987-1995); Index Medicus (1987-1995); program and abstracts of the 32nd (1992), 33rd (1993), 34th (1994), and 35th (1995) Interscience Conference on Antimicrobial Agents and Chemotherapy; bibliographic reviews of review articles; and package inserts. In vitro and in vivo studies on the pharmacokinetics, microbiology, pharmacology, and clinical effectiveness of ampicillin/sulbactam, ticarcillin/clavulanate, and piperacillin/tazobactam were evaluated. Many properties of the beta-lactam/beta-lactamase inhibitor combinations are similar. Differences in dosing, susceptibilities, and clinical applications are important considerations for clinicians. Potential roles for these agents in the clinical setting include pneumonia, intraabdominal infections, and soft tissue infections. A short discussion on susceptibility data interpretation is also presented. There are important differences among the available beta-lactam/beta-lactamase inhibitor combinations, such as spectra of activity, which need to be considered in choosing an agent for a patient-specific case. These products can be useful alternatives to conventional two- to three-drug regimens in mixed infections such as foot infections in patients with diabetes and hospital-acquired intraabdominal infections.

Cefoxitin in the Prevention And Treatment of Infections

A review of the literature indicates that cefoxitin is an effective single-agent therapy for community-acquired intra-abdominal infections, pelvic infections, and surgical prophylaxis. Hospital-acquired intra-abdominal infections may require the addition of an aminoglycoside.