[Research progress in the application of necrotic cavity lavage in the treatment of infected pancreatic necrosis].

Lavage has been used in the treatment of infected pancreatic necrosis(IPN) for a long time.It can be divided into peritoneal lavage and necrotic cavity lavage according to different parts of lavage.At present,peritoneal lavage is rarely used,while necrotic cavity lavage is widely used in laparotomy,minimally invasive surgery and endoscopic debridement and drainage for IPN patients.However,there is no unified standard for the type,method,duration and indication of stopping lavage.The application of lavage is controversial: proponents think that necrotic cavity lavage can dilute and remove residual or new necrotic tissue,remove inflammatory mediators and reduce the times of debridement,etc.While opponents think that lavage can not significantly reduce the concentration of phospholipase A2 and other bioactive substances,and is easy to form abscess and peripancreatic sepsis and cause infection to spread into the abdominal cavity and form peritonitis.In conclusion,necrotic cavity lavage can benefit some patients,especially those with smaller drainage diameter who underwent endoscopic debridement and percutaneous catheter drainage.However,whether it is necessary for patients with larger drainage diameter who underwent laparotomy or video-assisted debridement still needs to be further studied by randomized controlled trials.

A Novel Presentation of Tuberculosis with Intestinal Perforation in a Free-Ranging Australian Sea Lion (Neophoca cinerea).

We detail a novel presentation of tuberculosis associated with intestinal perforation in an endangered Australian sea lion (Neophoca cinerea) from South Australian waters and confirm the presence of this disease in the region of highest pup production. In February 2017, a 3-yr-old juvenile male died shortly after hauling out at the Kingscote beach on Kangaroo Island. On postmortem examination, we found a mid-jejunal intestinal perforation and partial obstruction (from a strangulating fibrous and granulomatous mesenteric mass), a marked multicentric abdominal fibrosing granulomatous lymphadenitis, and a large volume serosanguinous peritoneal effusion. Acid-fast bacteria were detected postmortem in cytologic preparations of the mesenteric lymph node and in histologic sections of jejunum and the encircling mass. Mycobacterial infection was confirmed by positive culture after 3 wk. Molecular typing using mycobacterial interspersed repetitive-unit-variable-number tandem-repeat typing with 12-locus analysis identified Mycobacterium pinnipedii. This case highlights the need for vigilance of zoonotic disease risk when handling pinnipeds, including in the absence of specific respiratory signs or grossly apparent pulmonary pathology. Increased serologic population surveillance is recommended to assess the species' risk from this and other endemic diseases, especially given its endangered status.

Diagnostic accuracy of 18F-FDG-PET in abdominal sepsis in rats.

PURPOSE: The objective of this study was to investigate the accuracy of 18F-FDG-PET in the diagnosis of multibacterial abdominal sepsis by cecum ligation and puncture (CLP) in rats. METHODS: Adult Wistar rats ( Rattus norvegicus ), weighing 227±35g, were allocated into a sepsis group by CLP (n=10) and sham group (n=10). 18F-FDG-PET using microPET was performed on all rats after 24 hours. RESULTS: All animals survived for postoperative 24h. The abdomen/liver ratio of the standardized uptake value (SUV) percentage was significantly higher in the sepsis group than in the sham (p=0.004). The ROC curve showed an accuracy of 18F-FDG-PET to detect abdominal sepsis of 88.9% (p=0.001), sensitivity of 90% and specificity of 88.9%. When a cut-off point of 79% of the ratio between the SUV on the abdominal region and liver was established, the sensitivity was 90%, specificity of 88.9%; positive and negative predictive values of 90.0% and 88.9%, respectively. CONCLUSIONS: The diagnostic accuracy of 18F-FDG-PET in rats with abdominal sepsis was significantly high. It was also demonstrated the predictive ability of the abdomen/liver SUV ratio to diagnose abdominal sepsis. These findings may have implications for the clinical setting, locating septic foci with PETscan.

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.

Diagnostic accuracy of 18F-FDG-PET in abdominal sepsis in rats

Abstract Purpose The objective of this study was to investigate the accuracy of 18F-FDG-PET in the diagnosis of multibacterial abdominal sepsis by cecum ligation and puncture (CLP) in rats. Methods Adult Wistar rats ( Rattus norvegicus ), weighing 227±35g, were allocated into a sepsis group by CLP (n=10) and sham group (n=10). 18F-FDG-PET using microPET was performed on all rats after 24 hours. Results All animals survived for postoperative 24h. The abdomen/liver ratio of the standardized uptake value (SUV) percentage was significantly higher in the sepsis group than in the sham (p=0.004). The ROC curve showed an accuracy of 18F-FDG-PET to detect abdominal sepsis of 88.9% (p=0.001), sensitivity of 90% and specificity of 88.9%. When a cut-off point of 79% of the ratio between the SUV on the abdominal region and liver was established, the sensitivity was 90%, specificity of 88.9%; positive and negative predictive values of 90.0% and 88.9%, respectively. Conclusions The diagnostic accuracy of 18F-FDG-PET in rats with abdominal sepsis was significantly high. It was also demonstrated the predictive ability of the abdomen/liver SUV ratio to diagnose abdominal sepsis. These findings may have implications for the clinical setting, locating septic foci with PETscan.

Comparison of Short-Course and Prolonged Antimicrobial Therapy in the Management of Intra-Abdominal Infections.

Background: Guidelines recommend an antimicrobial therapy duration of four to seven days for intra-abdominal infections (IAIs). Despite evidence that shorter treatments are appropriate for this disease state, longer durations frequently are utilized in clinical practice. This study compared the clinical outcomes of short course (SC) and prolonged course (PC) antimicrobial therapy for IAI. Methods: This was a noninterventional, retrospective, single-center study. Adults admitted with documented IAI who received antimicrobial treatment for ≥48 hours were included. Results: A total of 175 patients were enrolled, 73 patients receiving SC (≤7 days) and 102 patients receiving PC (>7 days) therapy. No significant differences were observed in the primary outcome of clinical cure (74% versus 67.6%; p = 0.367). Secondary outcomes including hospital length of stay (LOS) (5.5 versus 5.8 days; p = 0.372), intensive care unit (ICU) LOS (3 versus 5 days; p = 0.117), 28-day all-cause mortality rate (4.1% versus 2%; p = 0.651), and 30-day re-admission rate (19.2% versus 20.6%; p = 0.818) also were not significantly different. Conclusions: There was no significant difference in the rate of clinical cure between SC and PC antimicrobial therapy. These results further support guideline recommendations for a shorter duration of antimicrobial therapy in IAI.

Complicated intra-abdominal infections: a prospective validation study of the WSES Sepsis Severity Score.

INTRODUCTION: The World Society of Emergency Surgery (WSES) recently developed and validated a sepsis severity score for complicated intra-abdominal infections (cIAIs). We aimed to prospectively study the validity of this score in our local setting and compare it with global findings. METHODS: In a prospective study of 100 consecutive adult patients with cIAIs treated at Al-Ain Hospital, United Arab Emirates, from October 2014 to January 2016, we studied patients' demographics, disease, risk factors, WSES Sepsis Severity Score, management, hospital stay and mortality. Our findings were compared with those from a recent global multicentre prospective study from 53 countries (n = 4,496). RESULTS: Compared with global data, our patients were more likely to be male (p < 0.0001) and younger (p < 0.0001), with more appendicitis and perforated peptic ulcers (p < 0.0001), significantly lower sepsis severity score (p < 0.0001) and more delays in surgical intervention (p = 0.001). Nevertheless, they had similar adequate source control (p = 0.54) and surgical reinterventions (p = 0.63). Overall, our patients had a significantly lower mortality rate (1.0% vs. 9.3% in global data; p = 0.001). A direct logistic regression model showed that the WSES Sepsis Severity Score significantly predicted mortality (p < 0.0001), but our hospital's setting was not predictive of mortality compared with other hospitals (p = 0.18). CONCLUSION: Although our patient demographics and hospital's setting significantly differed from those of other international hospitals, the WSES Sepsis Severity Score was very accurate in predicting mortality among our patients, which supports its generalisability for all patient populations worldwide.

A pharmacokinetic case study of intravenous posaconazole in a critically ill patient with hypoalbuminaemia receiving continuous venovenous haemodiafiltration.

This article reports a pharmacokinetic case study of intravenous posaconazole in a 49-year-old male patient with intra-abdominal sepsis and hypoalbuminaemia receiving continuous venovenous haemodiafiltration. Concentration-time data following 300 mg intravenous posaconazole was analysed using a population pharmacokinetics approach. The 300-mg intravenous dose appears to be adequate for the treatment of yeast infections; however, for the treatment of invasive aspergillosis in isolated cases of critically ill patients with hypoalbuminaemia, the current dosing may not achieve desired exposure, although steady state exposure data are needed.

Progression into sepsis: an individualized process varying by the interaction of comorbidities with the underlying infection.

BACKGROUND: Development of sepsis is a process with significant variation among individuals. The precise elements of this variation need to be defined. This study was designed to define the way in which comorbidities contribute to sepsis development. METHODS: Three thousand five hundred nine patients with acute pyelonephritis (AP), community-acquired pneumonia (CAP), intraabdominal infections (IAI) or primary bacteremia (BSI) and at least two signs of the systemic inflammatory response syndrome were analyzed. The study primary endpoint was to define how comorbidities as expressed in the Charlson's comorbidity index (CCI) and the underlying type of infection contribute to development of organ dysfunction. The precise comorbidities that mediate sepsis development and risk for death among 18 comorbidities recorded were the secondary study endpoints. RESULTS: CCI more than 2 had an odds ratio of 5.67 for sepsis progression in patients with IAI between significantly higher than AP and BSI. Forward logistic regression analysis indicated seven comorbidities that determine transition into sepsis in patients with AP, four comorbidities in CAP, six comorbidities in IAI and one in BSI. The odds ratio both for progression to sepsis and death with one comorbidity or with two and more comorbidities was greater than in the absence of comorbidities. CONCLUSIONS: The study described how different kinds of infection vary in the degree to which they lead to sepsis. The number of comorbidities that enhances the risk of sepsis and death varies depending on the underlying infections.

Intra-abdominal infection combined with intra-abdominal hypertension aggravates the intestinal mucosal barrier dysfunction.

Some patients with intra-abdominal infection (IAI) may develop intra-abdominal hypertension (IAH) during treatment. The present study investigated the impact of IAI combined with IAH on the intestinal mucosal barrier in a rabbit model. Forty-eight New Zealand white rabbits were randomly divided into four groups: (i) IAI and IAH; (ii) IAI alone; (iii) IAH alone; and (iv) Control group. IAI model: cecal ligation and puncture for 48 h; IAH model: raised intra-abdominal pressure (IAP) of 20 mmHg for 4 h. Pathological changes in intestinal mucosa were confirmed by light and scanning electron microscopy. FITC-conjugated dextran (FITC-dextran) by gavage was used to measure intestinal mucosal permeability in plasma. Endotoxin, d-Lactate, and diamine oxidase (DAO) in plasma were measured to determine intestinal mucosal damage. Malonaldehyde (MDA), superoxide dismutase (SOD), and GSH in ileum tissues were measured to evaluate intestinal mucosal oxidation and reducing state. Histopathologic scores were significantly higher in the IAI and IAH group, followed by IAI alone, IAH alone, and the control group. FITC-dextran, d-Lactate, DAO, and endotoxin in plasma and MDA in ileum tissues had similar trends. GSH and SOD were significantly lowest the in IAI and IAH group. Occludin levels were lowest in the ileums of the IAI and IAH group. All differences were statistically significant (P-values <0.001). IAI combined with IAH aggravates damage of the intestinal mucosal barrier in a rabbit model. The combined effects were significantly more severe compared with a single factor. IAI combined with IAH should be prevented and treated effectively.

Anatomo-radiological correlation using 18-FDG-PET in abdominal sepsis model in rats. A preliminary study.

PURPOSE:: To examine a correlation of micro-PET images with photographic images of the digestive organs in abdominal sepsis model. METHODS:: Male Wistar rats weighing 265±18g were used. Abdominal sepsis was induced by ligature and cecal puncture. Micro-PET Images from abdominal cavity septic foci were obtained using 18-Fluoro-deoxyglucose, looking for a correlation with photographic images of abdominal cavity organs. Pearson's correlation test was used. RESULTS:: The mean standard uptake values (SUV) and lesion areas were 2.58±0.63SUVbwg/ml and 546.87±300.95mm2, respectively. There was a strong positive correlation between the two variables (r=0.863, p=0.137), which resulted in a coefficient of determination r2?0.75, meaning that 75% of SUV variation is explained by the lesion areas of digestive organs. CONCLUSION:: Micro-PET allows high throughput assessment of lesion count and volume in pre-clinical rat model of CPL abdominal sepsis.

Anatomo-radiological correlation using 18-FDG-PET in abdominal sepsis model in rats. A preliminary study

Abstract Purpose: To examine a correlation of micro-PET images with photographic images of the digestive organs in abdominal sepsis model. Methods: Male Wistar rats weighing 265±18g were used. Abdominal sepsis was induced by ligature and cecal puncture. Micro-PET Images from abdominal cavity septic foci were obtained using 18-Fluoro-deoxyglucose, looking for a correlation with photographic images of abdominal cavity organs. Pearson's correlation test was used. Results: The mean standard uptake values (SUV) and lesion areas were 2.58±0.63SUVbwg/ml and 546.87±300.95mm2, respectively. There was a strong positive correlation between the two variables (r=0.863, p=0.137), which resulted in a coefficient of determination r2?0.75, meaning that 75% of SUV variation is explained by the lesion areas of digestive organs. Conclusion: Micro-PET allows high throughput assessment of lesion count and volume in pre-clinical rat model of CPL abdominal sepsis.

Clinical Experience of Patients Receiving Doripenem-Containing Regimens for the Treatment of Healthcare-Associated Infections.

In this study, we retrospectively reviewed the clinical experience of patients receiving doripenem-containing regimens for the treatment of healthcare-associated infections (HCAIs) in a tertiary care center and assessed the clinical usefulness of doripenem therapy in this clinical setting. In this retrospective study, the medical records of all adult patients who had ever received doripenem-containing therapy for the treatment of HCAIs were reviewed between September 1, 2012 and August 31, 2014, and the following data were extracted: age, gender, type of infection, disease severity, underlying comorbidities or conditions, and laboratory results. Additionally, we also extracted data regarding the rates of mortality and clinical and microbiological response. A total of 184 adult patients with HCAIs who had received doripenem-containing therapy were included in this study. Respiratory tract infections (n = 91, 49.5%) were the most common type of infection, followed by urinary tract infections, intra-abdominal infections and skin and soft tissue infections. The mean APACHE II score was 14.5. The rate of clinical success was 78.2%, and the overall in-hospital mortality rate was only 13.0%. Among patients, in-hospital mortality was independently and significantly associated with APACHE II score (odds ratio (OR), 1.2825; 95% CI, 1.1123-1.4788) and achieving clinical success (OR, 0.003; 95% CI, 0.0003-0.409). In conclusion, the overall in-hospital mortality rate was low and the clinical success rate was high among HCAI patients receiving doripenem treatment. These results suggest that doripenem may be judiciously used for the treatment of patients with HCAIs.

Ventral abdominal wall defect correction in rats with contaminated meshes.

PURPOSE:: To investigate whether there is a difference between Marlex(r) and Dynamesh PP-light Marlex(r) meshes, in the abdominal wall defect correction, on rats in contaminated surgical site. METHODS:: Twenty-eight Wistar rats were divided into two groups of 14, and four subgroups of seven animals. All subgroups underwent similar surgical procedure. One group received the mesh Marlex(r) and the other Dynamesh PP-light(r) for correction of the defect. Before implanting, the meshes went through a contamination process, on which was used standard solution containing 10 UFC of Escherichia coli. Fragments of the animal's abdominal wall received macroscopic, microscopic and microbiological analysis. RESULTS:: There was no statistical significance in the analysis of macroscopic variables. Accentuated inflammatory process was shown in all subgroups. The foreign body type reaction was mild in all subgroups, except Dynamesh(r)-14, which was moderate with no statistical significance. The microbiological analysis of the meshes was also similar between the subgroups. CONCLUSION:: There was no difference between the meshes of Marlex(r) and Dynamesh PP-light(r) in the ventral abdominal wall defect correction on rats in contaminated surgical site.

Ventral abdominal wall defect correction in rats with contaminated meshes

ABSTRACT PURPOSE: To investigate whether there is a difference between Marlex(r) and Dynamesh PP-light Marlex(r) meshes, in the abdominal wall defect correction, on rats in contaminated surgical site. METHODS: Twenty-eight Wistar rats were divided into two groups of 14, and four subgroups of seven animals. All subgroups underwent similar surgical procedure. One group received the mesh Marlex(r) and the other Dynamesh PP-light(r) for correction of the defect. Before implanting, the meshes went through a contamination process, on which was used standard solution containing 10 UFC of Escherichia coli. Fragments of the animal's abdominal wall received macroscopic, microscopic and microbiological analysis. RESULTS: There was no statistical significance in the analysis of macroscopic variables. Accentuated inflammatory process was shown in all subgroups. The foreign body type reaction was mild in all subgroups, except Dynamesh(r)-14, which was moderate with no statistical significance. The microbiological analysis of the meshes was also similar between the subgroups. CONCLUSION: There was no difference between the meshes of Marlex(r) and Dynamesh PP-light(r) in the ventral abdominal wall defect correction on rats in contaminated surgical site.

High Prevalence of Hypervirulent Klebsiella pneumoniae Infection in China: Geographic Distribution, Clinical Characteristics, and Antimicrobial Resistance.

Hypervirulent Klebsiella pneumoniae (hvKP) is traditionally defined by hypermucoviscosity, but data based on genetic background are limited. Antimicrobial-resistant hvKP has been increasingly reported but has not yet been systematically studied. K. pneumoniae isolates from bloodstream infections, hospital-acquired pneumonia, and intra-abdominal infections were collected from 10 cities in China during February to July 2013. Clinical data were collected from medical records. All K. pneumoniae isolates were investigated by antimicrobial susceptibility testing, string test, extended-spectrum ß-lactamase (ESBL) gene detection, capsular serotypes, virulence gene profiles, and multilocus sequence typing. hvKP was defined by aerobactin detection. Of 230 K. pneumoniae isolates, 37.8% were hvKP. The prevalence of hvKP varied among different cities, with the highest rate in Wuhan (73.9%) and the lowest in Zhejiang (8.3%). Hypermucoviscosity and the presence of K1, K2, K20, and rmpA genes were strongly associated with hvKP (P < 0.001). A significantly higher incidence of liver abscess (P = 0.026), sepsis (P = 0.038), and invasive infections (P = 0.043) was caused by hvKP. Cancer (odds ratio [OR], 2.285) and diabetes mellitus (OR, 2.256) appeared to be independent variables associated with hvKP infections by multivariate analysis. Importantly, 12.6% of hvKP isolates produced ESBLs, and most of them carried blaCTX-M genes. Patients with neutropenia (37.5% versus 5.6%; P = 0.020), history of systemic steroid therapy (37.5% versus 5.6%; P = 0.020), and combination therapy (62.5% versus 16.7%; P = 0.009) were more likely to be infected with ESBL-producing hvKP. The prevalence of hvKP is high in China and has a varied geographic distribution. ESBL-producing hvKP is emerging, suggesting an urgent need to enhance clinical awareness, especially for immunocompromised patients receiving combination therapy.

Fatal Clostridium perfringens sepsis due to emphysematous gastritis and literature review.

A 76-year-old female patient was admitted to the Level I Emergency Department of University of Szeged with severe abdominal pain and vomiting. The clinical assessment with laboratory tests and radiological investigations confirmed severe sepsis associated with intravascular hemolysis and multiorgan failure and acute pancreatitis. On the abdominal CT, besides of other abnormalities, the presence of gas bubbles in the stomach, small intestines and liver were seen. The gastric alterations pointed to emphysematous gastritis. Despite of the medical treatment, the patient's condition quickly deteriorated and eight hours after admission the patient died. The autopsy evaluation revealed systemic infection of abdominal origin caused by gas-producing Gram-positive bacteria, and the post-mortem microbiological cultures confirmed the presence of Cloctridium perfringens in many abdominal organs. Emphysematous gastritis seemed to be the primary infectious focus.

Multicenter Prospective Cohort Study of Renal Failure in Patients Treated with Colistin versus Polymyxin B.

Nephrotoxicity is the main adverse effect of colistin and polymyxin B (PMB). It is not clear whether these two antibiotics are associated with different nephrotoxicity rates. We compared the incidences of renal failure (RF) in patients treated with colistimethate sodium (CMS) or PMB for ≥48 h. A multicenter prospective cohort study was performed that included patients aged ≥18 years. The primary outcome was renal failure (RF) according to Risk, Injury, Failure, Loss, and End-stage renal disease (RIFLE) criteria. Multivariate analysis with a Cox regression model was performed. A total of 491 patients were included: 81 in the CMS group and 410 in the PMB group. The mean daily doses in milligrams per kilogram of body weight were 4.2 ± 1.3 and 2.4 ± 0.73 of colistin base activity and PMB, respectively. The overall incidence of RF was 16.9% (83 patients): 38.3% and 12.7% in the CMS and PMB groups, respectively (P< 0.001). In multivariate analysis, CMS therapy was an independent risk factor for RF (hazard ratio, 3.35; 95% confidence interval, 2.05 to 5.48;P< 0.001) along with intensive care unit admission, higher weight, older age, and bloodstream and intraabdominal infections. CMS was also independently associated with a higher risk of RF in various subgroup analyses. The incidence of RF was higher in the CMS group regardless of the patient baseline creatinine clearance. The development of RF during therapy was not associated with 30-day mortality in multivariate analysis. CMS was associated with significantly higher rates of RF than those of PMB. Further studies are required to confirm our findings in other patient populations.

Sub-Inhibitory Concentration of Piperacillin-Tazobactam May be Related to Virulence Properties of Filamentous Escherichia coli.

Sub-inhibitory concentrations of antibiotics are always generated as a consequence of antimicrobial therapy and the effects of such residual products in bacterial morphology are well documented, especially the filamentation generated by beta-lactams. The aim of this study was to investigate some morphological and pathological aspects (virulence factors) of Escherichia coli cultivated under half-minimum inhibitory concentration (1.0 µg/mL) of piperacillin-tazobactam (PTZ sub-MIC). PTZ sub-MIC promoted noticeable changes in the bacterial cells which reach the peak of morphological alterations (filamentation) and complexity at 16 h of antimicrobial exposure. Thereafter the filamentous cells and a control one, not treated with PTZ, were comparatively tested for growth curve; biochemical profile; oxidative stress tolerance; biofilm production and cell hydrophobicity; motility and pathogenicity in vivo. PTZ sub-MIC attenuated the E. coli growth rate, but without changes in carbohydrate fermentation or in traditional biochemical tests. Overall, the treatment of E. coli with sub-MIC of PTZ generated filamentous forms which were accompanied by the inhibition of virulence factors such as the oxidative stress response, biofilm formation, cell surface hydrophobicity, and motility. These results are consistent with the reduced pathogenicity observed for the filamentous E. coli in the murine model of intra-abdominal infection. In other words, the treatment of E. coli with sub-MIC of PTZ suggests a decrease in their virulence.