Nosocomial Intra-abdominal Infections Research Articles

A multicenter epidemiology study on the risk factors and clinical outcomes of nosocomial intra-abdominal infections in China: results from the Chinese Antimicrobial Resistance Surveillance of Nosocomial Infections (CARES) 2007-2016.

ObjectiveThis study aimed to determine the risk factors for intra-abdominal infections (IAIs), assess the clinical outcomes of IAIs, and investigate the spectrum and antimicrobial resistance of major pathogens causing IAIs.Patients and methodsThis prospective observational study enrolled patients from the Chinese Antimicrobial Resistance Surveillance of Nosocomial Infections (CARES) program between 2007 and 2016. Data on the clinicopathological factors and causative pathogens were collected. The results of antimicrobial susceptibility tests were interpreted according to the minimum inhibitory concentration (MIC) interpretive breakpoints recommended by the Clinical and Laboratory Standards Institute in 2017.ResultsA total of 2,756 patients were included. The 30-day all-cause mortality was 9.5% (262/2,756). Multivariable analysis showed that the following independent risk factors were associated with the 30-day mortality: age >60 years, pulmonary disease, tracheal cannula, infection occurring in intensive care unit (ICU), prior admission within 3 months, antibiotic use before infection, recent use of immunosuppressants, and multidrug-resistant organisms. In addition, 2,913 clinical isolates were collected. The Gram-negative and Gram-positive bacteria accounted for 70.8% and 29.2% of all isolates, respectively. The most common pathogens were Escherichia coli (33.4%), Klebsiella pneumoniae (10.8%), and Enterococcus faecium (10.7%). Pseudomonas aeruginosa and Acinetobacter baumannii were the most common non-Enterobacteriaceae Gram-negative pathogens. E. faecium, Enterococcus faecalis, and Staphylococcus aureus were the most common Gram-positive pathogens. E. coli, A. baumannii, and Enterobacter cloacae were more commonly found in ICU patients than in non-ICU patients. Overall, the antibiotics tested in the CARES exhibited diminished susceptibility to pathogens over the study period, especially extended spectrum β-lactamase producing isolates.ConclusionConsidering the current data set and high-level resistance of intra-abdominal pathogens to various antibiotics, further monitoring of the epidemiology of IAIs and their susceptibility to antibiotics through the CARES is warranted.

Use of aztreonam in association with cefepime for the treatment of nosocomial infections due to multidrug-resistant strains of Pseudomonas aeruginosa to β-lactams in ICU patients: A pilot study

ObjectivesResistance to all β-lactams is emerging among Pseudomonas aeruginosa (PA) clinical isolates. Aztreonam and cefepime act synergistically in vitro against AmpC overproducing PA isolates. The objective of this study was to evaluate the clinical efficacy of this treatment in ICU patients infected with multidrug-resistant PA. Material and methodsRetrospective study (2 years, 2 ICUs) in a tertiary university hospital. Inclusion criteria were proven infection with evidence of a bacterial strain of PA resistant to all β-lactams and treated with the association of at least aztreonam plus cefepime. Treatment was considered effective for pneumonia using CPIS scores at the end of treatment and for other infections, using the SOFA score and signs of infection improvement at the end of treatment. Infectious episodes were classified as cure or failure. ResultsThirteen patients were included (10 nosocomial pneumonia, 3 nosocomial intra-abdominal infections). The median [25th–75th percentiles] admission SAPS2 score was 54 [51–69] and the median SOFA score at the beginning of infection was 7 [4–8]. The median CPIS scores for pneumonia at the beginning and end of treatment were 9 [7–10.5] and 2 [0.75–5.5]. The duration of treatment with the combination of aztreonam plus cefepime was 14 days [9.5–16]. Nine episodes were classified as cures and 4 as failures, indicating a clinical efficacy of 69.2%. Overall mortality was 38.5%. DiscussionThese data suggest that the association of cefepime plus aztreonam could be an attractive alternative in the treatment of infections with multidrug-resistant PA to all β-lactams with a clinical efficacy rate of 69%.

Epidemiological study of community- and hospital-acquired intraabdominal infections

PurposeTo investigate and analyze the clinical and etiological characteristics of community-acquired intraabdominal infections (CIAIs) and hospital-acquired or nosocomial intraabdominal infections (NIAIs) in a comprehensive hospital, to understand the characteristics, pathogen composition, and drug resistance of CIAIs as well as NIAIs, and to provide a reference for clinical treatment. MethodsWe collected the clinical data of patients with intraabdominal infections admitted to our hospital from June 2013 to June 2014. In vitro drug sensitivity tests were conducted to separate pathogens, and the data were analyzed using the WHONET 5.4 software and SPSS 13.0 software. ResultsA total of 221 patients were enrolled in the study, including 144 with CIAIs (55 mild-moderate and 89 severe) and 77 with NIAIs. We isolated 322 pathogenic strains, including 234 strains of gram-negative bacteria, 82 strains of gram-positive bacteria, and 6 strains of fungi. Based on clinical features, NIAIs and severe CIAIs presented significantly higher values in age, length of hospital stay, mortality, and the incidence of severe intra-abdominal infection than mild-moderate CIAIs (p < 0.05). There was no significant difference in the prognosis between NIAIs and severe CIAIs. Primary diseases leading to CIAIs and NIAIs mostly were hepatobiliary diseases and gastrointestinal diseases respectively. Bacteria isolated from various types of IAIs mainly were Enterobacteriaceae; mild-moderate CIAIs mostly were mono-infection of gram-negative bacteria; NIAIs mostly were mixed infections of gram-negative and gram-positive bacteria; and severe CIAIs were from either type of infection. The rate of Extended Spectrum β-Lactamase-producing Escherichia coli and Klebsiella pneumoniae was much higher in NIAIs than in CIAIs (p < 0.05). The antimicrobial drug sensitivity of gram-negative bacteria isolated from NIAIs was significantly lower than that of CIAIs. ConclusionCIAIs and NIAIs have their own unique clinical features and epidemiological features of pathogens which should be considered during the initial empiric therapy for the rational use of antimicrobial drugs. Regional IAIs pathogenic bacteria have their own features in drug resistance, slightly different from some recommendations of 2010 Infectious Diseases Society of America guidelines.

Antimicrobial susceptibility of pathogens isolated from patients with complicated intra-abdominal infections at five medical centers in Taiwan that continuously participated in the Study for Monitoring Antimicrobial Resistance Trends (SMART) from 2006 to 2010

The Study for Monitoring Antimicrobial Resistance Trends (SMART) is a worldwide surveillance program designed to longitudinally monitor the in vitro activity of antimicrobial agents against pathogens that cause intra-abdominal infections (IAIs). In this study, trends in antimicrobial resistance during the period 2006 to 2010 were analyzed at five tertiary-care hospitals in Taiwan. Enterobacteriaceae accounted for the majority (80.9%) of the 2417 Gram-negative isolates, and the two most common species were Escherichia coli (38.8%) and Klebsiella pneumoniae (23.5%). The rates of susceptibility of Enterobacteriaceae isolates to cephalosporins decreased during the study period. Although carbapenems, fluoroquinolones, piperacillin-tazobactam, and amikacin were active in vitro against more than 80% of the Enterobacteriaceae isolates, the activity of carbapenems declined during the study period. Extended-spectrum β-lactamase (ESBL) production in E. coli was steady, but that in K. pneumoniae decreased during the study period. The rate of ESBL-producing species was three-fold higher among patients with nosocomial IAIs than among patients with community-acquired IAIs. The majority of isolates from liver were K. pneumoniae (69%) and very few of those isolates were ESBL producers (0.9%). Pseudomonas aeruginosa (9.3%) and Acinetobacter baumannii (3.8%) were the two most common non-Enterobacteriaceae. P. aeruginosa showed improved susceptibility, whereas A. baumannii showed a rapid development of resistance during the study period. There was marked geographic variation in resistance patterns of the isolates obtained during the study period. Northern Taiwan had the highest rate of ESBL producers and the highest rate of ceftazidime resistance among P. aeruginosa isolates. Central Taiwan had the lowest rate of ESBL producers but the highest rates of carbapenem resistance among P. aeruginosa and A. baumannii isolates. Continuous monitoring and regular updates of epidemiological data are needed to guide appropriate empiric antimicrobial therapy.

Mortality for intra-abdominal infection is associated with intrinsic risk factors rather than the source of infection

Intra-abdominal infections (IAIs) are an important cause of mortality and morbidity. Nosocomial IAIs (NIAIs) have been associated with higher mortality than community-acquired IAIs (CIAIs). We hypothesized that intrinsic risk factors were a better predictor of mortality than the type of infection. Patients with IAI treated at a single urban academic hospital over 8 years (June 1999-June 2007) were retrospectively reviewed. Data collected included demographics, comorbidities, source of infection, type of infection (community vs nosocomial), type of intervention (operation versus percutaneous drainage), and postoperative complications. Charlson Comorbidity Index and multiple organ dysfunction (MOD) scores were evaluated at admission and on postoperative day 7 (POD-7). There were 452 patients; 234 (51.8%) had CIAI and 218 (48.2%) had NIAI. The mean age was 51.3 +/- 0.8. The most common source of CIAI was the appendix (n = 129, 28.5%); 137 patients with NIAI had postoperative infections (30.3%). When patients with appendicitis were excluded, there was no difference in mortality or complications between patients with CIAI and NIAI. Logistic regression analysis demonstrated catheter-related bloodstream infection (P < .001; OR 7.3, 95% CI, 2.5-22.2), cardiac event (P < .001; OR 6.0, 95% CI, 2.3-16.1), and age > or = 65 (P = .009; OR 3.8, 95% CI, 1.4-8.8) to be independent risk factors for mortality. Among patients who failed initial therapy, a non-appendiceal source of infection (P < .001; OR 4.7, 95% CI, 2.3-9.8) and a Charlson score > or =2 (P = .033; OR 1.6, 95% CI, 1.0-2.6) were determined to be independent risk factors. Non-appendiceal source of infection (P = .001, OR 3.3, 95% CI, 1.6-7.0) and POD-7 MOD score > or =4 (P < .001; OR 3.4, 95% CI, 1.9-6.0) were found to be independent predictors for re-intervention. These results suggest mortality from IAI is strongly related to age and organ dysfunction; however, catheter-related bloodstream infection and postoperative cardiac events have a greater effect on outcome.

Intra-abdominal Infections: Etiology, Epidemiology, Microbiological Diagnosis and Antibiotic Resistance

Intra-abdominal infections (IAIs) are commonly encountered in clinical practice. The etiology of these infections, often polymicrobial in nature, can be variable and usually includes organisms derived from the gut microbiota. In community-acquired IAIs enterobacteria predominate (mostly Escherichia coli) in combination with anaerobes (mostly Bacteroides fragilis). In nosocomial IAIs, which can complicate abdominal surgery, other pathogens can also play a role, such as Pseudomonas aeruginosa, Acinetobacter baumannii, Staphylococcus aureus, Enterococcus spp. and Candida spp. Diagnostic microbiology of IAIs is complex and plays a relevant role, especially in some situations (e.g. presence of foreign bodies, potential presence of resistant or uncommon pathogens, nosocomial infections in subjects with risk factors). Antibiotic resistance issues are currently encountered in most pathogenic species causing IAIs. Resistance affects all major classes of antimicrobial agents, often involving multiple classes and resulting in complex resistance phenotypes for which only a very limited number of drugs remain active.

Clinical and microbiological profiles of community-acquired and nosocomial intra-abdominal infections: results of the French prospective, observational EBIIA study

The EBIIA (Etude épidémiologique Bactério-clinique des Infections Intra-Abdominales) study was designed to describe the clinical, microbiological and resistance profiles of community-acquired and nosocomial intra-abdominal infections (IAIs). From January to July 2005, patients undergoing surgery/interventional drainage for IAIs with a positive microbiological culture were included by 25 French centres. The primary endpoint was the epidemiology of the microorganisms and their resistance to antibiotics. Multivariate analysis was carried out using stepwise logistic regression to assess the factors predictive of death during hospitalization. Three hundred and thirty-one patients (234 community-acquired and 97 nosocomial) were included. The distribution of the microorganisms differed according to the type of infection. Carbapenems and amikacin were the most active agents in vitro against Enterobacteriaceae in both community-acquired and nosocomial infections. Against Pseudomonas aeruginosa, amikacin, imipenem, ceftazidime and ciprofloxacin were the most active agents in community-acquired infections, while imipenem, cefepime and amikacin were the most active in nosocomial cases. Against the Gram-positive bacteria, vancomycin and teicoplanin were the most active in both infections. Against anaerobic bacteria, the most active agents were metronidazole and carbapenems in both groups. Empirical antibiotic therapy adequately targeted the pathogens for 63% of community-acquired and 64% of nosocomial peritonitis. The presence of one or more co-morbidities [odds ratio (OR) = 3.17; P = 0.007], one or more severity criteria (OR = 4.90; P < 0.001) and generalized peritonitis (OR = 3.17; P = 0.006) were predictive of death. The principal results of EBIIA are a higher diversity of microorganisms isolated in nosocomial infections and decreased susceptibility among these strains. Despite this, the adequacy of treatment is comparable in the two groups.

The empiric treatment of nosocomial intra-abdominal infections

The treatment of complicated intra-abdominal infections continues to challenge physicians, primarily because of the polymicrobial nature of these infections coupled with the high risk of complications and even death among the more severe patients. The initial selection of antimicrobial therapy for treatment of nosocomial intraabdominal infections is extremely important because an association has been shown between inappropriate empiric antimicrobial therapy and delayed clinical resolution, increased length of hospital stay, and an increased risk of mortality. Moreover, it is becoming more frequent for isolates recovered from patients to possess multiple resistance factors (e.g., extended-spectrum beta-lactamases [ESBLs], vancomycin-resistant enterococci [VRE]). Therefore, when selecting empiric antimicrobial therapy, the physician must consider the likelihood of encountering one of these difficult-to-treat isolates and select an agent or agents with anticipated activity against such organisms. Here, we discuss the merits and limitations of empiric therapy for nosocomial intra-abdominal infections, review the current guidelines for treatment, and discuss the therapeutic options currently available.

Infectiological diagnostic problems in tertiary peritonitis

The tertiary peritonitis causes the highest mortality in intraabdominal infections. Surgical interventions and antibiotic therapy may only provide an incomplete impact on nosocomial infections acquired at an intensive care unit (ICU) [Nathens et al., World J Surg 22:158-163, 28]. To open up new resources in the management, in particular, in the previous infectious diagnostic, the aim was to investigate the infectious course as well as the diagnostic value of laboratory parameters and microbiological monitoring. In this retrospective patient cohort study from the Surgical ICU of a University Hospital (capacity, n=12), overall, 60 patients with a tertiary peritonitis were enrolled. Approximately 20% of the patients with an intraabdominal infection developed a tertiary peritonitis. A tertiary peritonitis can more frequently develop in nosocomial intraabdominal infections, in particular, in case of necrotizing pancreatitis. The device-associated infection rate in the spectrum of nosocomial infections is sevenfold higher than in all ICU patients. Compared with the secondary peritonitis, its mortality is double as high: 35%. In the diagnostic characterizing the course of the nosocomial, prognosis-relevant infections, usual inflammatory parameters show a considerable loss of their sensitivity with a range from 35-57%. By the mean of a routine microbiological monitoring, 47.3% of the analysed subsequent infections could be identified at an early stage. In patients with a severe infection, an early diagnostic and treatment of infectious "second hits" can improve the complication rate and prognosis. During the prolonged and complicated septic course of tertiary peritonitis, an additional routine microbiological monitoring contributed effectively to early detection and diagnostic of nosocomial infections. Further studies to investigate the value and efficacy of such monitoring, which have been abandoned, should be undertaken in infectious high-risk patients.

Guideline for the management of nosocomial infections in South Africa.

To write a guideline for the management and prevention of nosocomial infections in South Africa in view of the following: Nosocomial infections are a common and increasing problem globally, including South Africa. Widely varying standards of prevention and management of these important infections. Increasing and emerging antimicrobial resistance among commonly isolated pathogens. The significant economic burden of these infections on the health care system as well as their impact on patient morbidity and mortality. The main aims of the guideline are to provide recommendations for the initial choice of antimicrobial agents and the appropriate management of these infections encompassing the following conditions: (i) nosocomial pneumonia, health care-associated pneumonia and ventilator-associated pneumonia; (ii) nosocomial bloodstream infections; (iii) nosocomial intravascular infections; (iv) nosocomial urinary tract infections; (v) nosocomial intra-abdominal infections; and (vi) nosocomial surgical skin and soft-tissue infections. Working group of clinicians from relevant disciplines, following detailed literature review. These include details of the likely pathogens, an appropriate diagnostic approach, antibiotic treatment options and appropriate preventive strategies. The guideline document was endorsed by the South African Thoracic Society, the Critical Care Society of Southern Africa and the Federation of Infectious Diseases Societies of Southern Africa.

Guideline for the management of nosocomial infections in South Africa

Objective: To write a guideline for the management and prevention of nosocomial infections in South Africa in view of the following: i) nosocomial infections are a common and increasing problem globally, including South Africa; ii) widely varying standards of prevention and management of these important infections; iii) increasing and emerging antimicrobial resistance among commonly isolated pathogens, and iv) the significant economic burden of these infections on the healthcare system as well as their impact on patient morbidity and mortality. The main aims of the guideline are to provide recommendations for the initial choice of antimicrobial agents and the appropriate management of these infections encompassing the following conditions: i) nosocomial pneumonia, healthcare-associated pneumonia and ventilator-associated pneumonia; (ii) nosocomial bloodstream infections; (iii) nosocomial intravascular infections; (iv) nosocomial urinary tract infections; (v) nosocomial intra-abdominal infections; and (vi)...

Empiric Treatment of Nosocomial Intra-Abdominal Infections: A Focus on the Carbapenems

Serious nosocomial intra-abdominal infections are associated with high morbidity and mortality and represent a substantial drain on healthcare resources. Effective management of this type of infection requires the early use of appropriate, broad-spectrum empiric antimicrobial therapy. The consequences of delayed or inappropriate antimicrobial treatment can be severe-leading to an increased risk of death, re-operation, or prolonged hospitalization. Therefore, it is necessary to begin treatment as soon as possible with the most appropriate regimen, in terms of spectrum, timing, and duration. Review of pertinent English-language literature. Serious nosocomial intra-abdominal infections require broad-spectrum coverage because of the wide range of possible pathogens, which include difficult-to-treat organisms such as Pseudomonas aeruginosa and Bacteroides spp., and resistant strains of Klebsiella spp., Escherichia coli, and methicillin-resistant Staphylococcus aureus acquired from the hospital flora. The early use of appropriate, broad-spectrum empiric antimicrobial therapy for treating high-risk patients with intra-abdominal infections is considered, and appropriate use of the carbapenems, meropenem, and imipenem/cilastatin, is described. The carbapenems meropenem and imipenem/cilastatin have a spectrum of antimicrobial activity that covers the majority of expected pathogens, including anaerobes, as well as difficult-to-treat and resistant gram-negative strains. Early and appropriate use can reduce mortality and morbidity. Data from published clinical trials support the clinical effectiveness of these two carbapenems in intra-abdominal infections.

The Role of β-Lactam Antimicrobials as Single Agents in Treatment of Intra-Abdominal Infection

Broad-spectrum beta-lactam antibiotics have several advantages in the treatment of intra-abdominal infections. These agents are effective against gram-negative rods and anaerobes, reach therapeutic levels rapidly after parenteral administration, and, in the absence of penicillin allergy, generally exhibit low toxicity. The second-generation cephalosporins (e.g., cefoxitin, cefotetan) are used widely in surgical prophylaxis, trauma, and treatment of mild-to-moderate community-acquired infections, but limitations in their spectra and microbial resistance restrict their utility in more serious infections. Extended-spectrum penicillin/beta-lactamase-inhibitor combinations are effective in the treatment of intra-abdominal infections and include enterococci in their spectrum. Gram-negative aerobe resistance has developed to ampicillin/sulbactam. Piperacillin/tazobactam, a ureidopenicillin with increased gram-negative coverage and enhanced antipseudomonal activity, has proved to be effective in clinical trial therapy for intra-abdominal infections. The very broad spectrum carbapenems--imipenem/cilastatin and meropenem--are effective for serious infections or resistant organisms and are often used in the intensive care unit or for nosocomial intra-abdominal infection. These classes of beta-lactams comprise a range of antimicrobials that can be targeted effectively as single agents to both prevention and treatment of intra-abdominal infection.

Metal injection moulding (MIM) of course iron powders

Intra-abdominal infections (IAIs) are an important cause of mortality and morbidity. Nosocomial IAIs (NIAIs) have been associated with higher mortality than community-acquired IAIs (CIAIs). We hypothesized that intrinsic risk factors were a better predictor of mortality than the type of infection.Patients with IAI treated at a single urban academic hospital over 8 years (June 1999–June 2007) were retrospectively reviewed. Data collected included demographics, comorbidities, source of infection, type of infection (community vs nosocomial), type of intervention (operation versus percutaneous drainage), and postoperative complications. Charlson Comorbidity Index and multiple organ dysfunction (MOD) scores were evaluated at admission and on postoperative day 7 (POD-7).There were 452 patients; 234 (51.8%) had CIAI and 218 (48.2%) had NIAI. The mean age was 51.3 ± 0.8. The most common source of CIAI was the appendix (n = 129, 28.5%); 137 patients with NIAI had postoperative infections (30.3%). When patients with appendicitis were excluded, there was no difference in mortality or complications between patients with CIAI and NIAI. Logistic regression analysis demonstrated catheter-related bloodstream infection (P < .001; OR 7.3, 95% CI, 2.5–22.2), cardiac event (P < .001; OR 6.0, 95% CI, 2.3–16.1), and age ≥ 65 (P = .009; OR 3.8, 95% CI, 1.4–8.8) to be independent risk factors for mortality. Among patients who failed initial therapy, a non-appendiceal source of infection (P < .001; OR 4.7, 95% CI, 2.3–9.8) and a Charlson score ≥2 (P = .033; OR 1.6, 95% CI, 1.0–2.6) were determined to be independent risk factors. Non-appendiceal source of infection (P = .001, OR 3.3, 95% CI, 1.6–7.0) and POD-7 MOD score ≥4 (P < .001; OR 3.4, 95% CI, 1.9–6.0) were found to be independent predictors for re-intervention.These results suggest mortality from IAI is strongly related to age and organ dysfunction; however, catheter-related bloodstream infection and postoperative cardiac events have a greater effect on outcome.