The harmful effects of overlooking acute bacterial prostatitis.

Prostatitis is a major urological disease affecting 25%-50% of men over their lifetime. However, prostatitis is often overlooked in nonurologic departments due to its sometimes indeterminate symptoms. In this review, we describe how to recognize and treat acute bacterial prostatitis, which manifests as a clinical problem in other departments as well as urology, to help prevent this disease from being overlooked. There are several possible negative effects of not recognizing acute bacterial prostatitis (ABP). First, initial treatment can fail. In the hyperacute phase, common antibiotics are often effective, but in rare cases, such antibiotics may not be effective. In addition, once ABP progresses to form a prostate abscess, potentially avoidable surgical interventions are often needed. A second issue is the transition to chronic prostatitis. If chronic bacterial prostatitis progresses, treatment requires long-term antibiotic administration and the response rate is not high. Some patients may have to deal with urinary tract infections for the rest of their lives. Finally, there is the problem of overlooking the underlying disease. ABP is rare in healthy adult men without underlying disease, including sexually transmitted diseases as well as benign prostatic hyperplasia, urinary stones, and malignant tumors, and may not be obvious. When examining patients with fever of unknown origin, it is necessary to exclude not only infectious diseases but also collagen diseases and malignant tumors. If there are any doubts, we recommend a rectal exam and consultation with a urologist.

Intralesional Chemotherapy for Prostate Cancer: In vivo Proof of Principle.

INTRODUCTION: Prostate cancer (PCA) is one of the most common cancers in the world, and current therapies are debilitating to patients. To develop a novel modality for the treatment of PCA, we evaluated the efficacy of intralesional administration of the Sirt3 activator Honokiol (HK) and the NADPH oxidase inhibitor Dibenzolium (DIB). METHODS: We used a well-established transgenic adenocarcinoma mouse prostate (TRAMP-C2) model of hormone-independent PCA. MTS assay, apoptosis assay, wound healing assay, transwell invasion assay, RT-qPCR, and Western blotting were conducted in vitro, and HK and DIB were intratumorally administered to mice bearing TRAMP-C2 tumors. Tumor size and weight were observed over time. After removing tumors, H-E staining and immunohistochemistry (IHC) staining were conducted. RESULTS: Treatment by HK or DIB showed an inhibitory effect on cell proliferation and migration in PCA cells. Poor ability to induce apoptosis in vitro, insufficient expression of caspase-3 on IHC staining, and increased necrotic areas on H-E staining indicated that necrosis plays an important role in cell death in treating groups by HK or DIB. RT-PCR, Western blotting, and IHC staining for epithelial mesenchymal transition (EMT) markers suggested that EMT was suppressed by HK and DIB individually. In addition, HK induced activation of CD3. Mouse experiments showed safe antitumor effects in vivo. CONCLUSIONS: HK and DIB suppressed PCA proliferation and migration. Further research will explore the effects of HK and DIB at the molecular level to reveal new mechanisms that can be exploited as therapeutic modalities.

Molecular characteristics and genetic analysis of the genes related to carbapenemase, efflux pump, and outer membrane proteins in carbapenem-resistant Klebsiella pneumoniae.

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is a life-threatening pathogen that has not been fully investigated on a molecular basis. Therefore, the molecular mechanisms of carbapenem resistance in CRKP collected from medical institutions in Hyogo Prefecture has been analyzed. Antimicrobial susceptibilities and the presence of carbapenemase along with epidemiological analyzes using multilocus sequence typing (MLST) have been investigated. The relative expression of efflux pump genes and mutations of ompK35 and ompK36, encoding the outer membrane porin, were also assessed for their relationship with carbapenem resistance. Most of the collected 22 CRKP isolates were non-susceptible to imipenem (68.2%), meropenem (90.9%), and ertapenem (81.8%), but all 22 strains were susceptible to colistin. Twelve strains (54.5%) were detected for carbapenemase genes such as blaIMP-6. Sequence type 37 was detected by MLST in 10 strains (45.5%). Non-carbapenemase-producing strains had high resistance rates for three carbapenems, and the main cause of resistance was ompK35 mutation. In conclusion, the main cause of resistance was imipenemase metallo-ß-lactamase (IMP-6) production in carbapenemase-producing strains, and ompK35 mutation in non-carbapenemase-producing strains. Susceptibility to carbapenem did not differ in CRKP regardless of carbapenemase production, except for imipenem susceptibility. This result contributes to a more insightful understanding of the mechanisms of CRKP in Japan.

A comparison of the impact of the COVID-19 pandemic on urological surgeries in Japan and Taiwan.

OBJECTIVE: We report the impact of the COVID-19 pandemic on urological surgeries and hospital policies at two hospitals in Japan and Taiwan. METHODS: We retrospectively surveyed the number of surgeries every 3 months in the Urology Department of Kobe University Hospital (KUH), Kobe, Japan before (January 2019-March 2020) and after (April 2020-September 2021) the COVID-19 outbreak, and in the Urology Department of Shuang Ho Hospital, Taipei Medical University (SHH-TMU), Taiwan before (January 2021-March 2021) and after (April 2021-September 2021) the outbreak, and compared the averages and types of surgery. RESULTS: In Kobe, COVID-19 patients were stratified such that other regional hospitals gave priority to treating COVID-19 while KUH gave priority to treating non-COVID-19 patients. In KUH, the number of surgeries did not change significantly, 237.2 ± 29.6 versus 246.3 ± 20.8 (p = 0.453). In Taiwan COVID-19 patients increased sharply in May 2021, and teaching hospitals in Taiwan were obliged to provide 20% of their total beds for COVID-19 patients. At SHH-TMU, there was a 33.3% drop in the number of surgeries during April-June 2021 compared to the pre-pandemic average. However, no significant changes were observed, 423.4 ± 68.4 versus 373 ± 91.0 (p = 0.298), because of the subsequent success in controlling the COVID-19 infection. CONCLUSIONS: The comparison of infection control measures between the two countries revealed that while both KUH and SHH-TMU successfully maintained the number of surgeries, the reasons for this were different for each.

Retrospective Observational Study of Risk Factors for Febrile Infectious Complications after Urodynamic Studies in Patients with Suspected Neurogenic Lower Urinary Tract Disturbance.

INTRODUCTION: We retrospectively investigated the risk factors for post-urodynamic study (UDS) infectious complications in long-term hospitalized inpatients with suspected neurogenic lower urinary tract disturbance (NLUTD) in a monocenter study, to accurately assess post-UDS urinary tract infections (UTI). METHODS: We retrospectively analyzed data including background information, UDS-related data, and potential risk factors for infection from 489 NLUTD-suspected inpatients who underwent UDS from 2015 to 2019 and examined the risk factors for post-UDS infectious complications using univariate and multivariate statistical analyses. RESULTS: Symptomatic post-UDS UTI occurred in 20 out of 489 (4.1%) patients, including 3 (15%) with recurrent UTI. During follow-up prior to UDS for 1 year, 220 cases were investigated by urine culture revealing Escherichia coli (n = 77), Klebsiella pneumoniae (n = 29), Enterococcus faecalis (n = 18), extended-spectrum beta-lactamase-producing E. coli (n = 17), and Pseudomonas aeruginosa (n = 9). As risk factors for post-UDS infectious complications, American Spinal Injury Association impairment scale (AIS): AIS ≧ C (A or B or C) (hazard ratio: 4.29, p = 0.0076), management method of urination (hazard ratio: 4.30, p = 0.048), and age (hazard ratio: 1.04, p = 0.025) were significantly correlated with the occurrence of post-UDS infection. CONCLUSIONS: The significant risk factors for post-UDS UTI were AIS ≧ C, management method of urination, and age in the suspected NLUTD patient context. This study was originally started with the goal of reducing unnecessary antibiotics and may contribute to the proper use of antibiotics based on antimicrobial stewardship.

Historical change of El Niño properties sheds light on future changes of extreme El Niño.

El Niño's intensity change under anthropogenic warming is of great importance to society, yet current climate models' projections remain largely uncertain. The current classification of El Niño does not distinguish the strong from the moderate El Niño events, making it difficult to project future change of El Niño's intensity. Here we classify 33 El Niño events from 1901 to 2017 by cluster analysis of the onset and amplification processes, and the resultant 4 types of El Niño distinguish the strong from the moderate events and the onset from successive events. The 3 categories of El Niño onset exhibit distinct development mechanisms. We find El Niño onset regime has changed from eastern Pacific origin to western Pacific origin with more frequent occurrence of extreme events since the 1970s. This regime change is hypothesized to arise from a background warming in the western Pacific and the associated increased zonal and vertical sea-surface temperature (SST) gradients in the equatorial central Pacific, which reveals a controlling factor that could lead to increased extreme El Niño events in the future. The Coupled Model Intercomparison Project phase 5 (CMIP5) models' projections demonstrate that both the frequency and intensity of the strong El Niño events will increase significantly if the projected central Pacific zonal SST gradients become enhanced. If the currently observed background changes continue under future anthropogenic forcing, more frequent strong El Niño events are anticipated. The models' uncertainty in the projected equatorial zonal SST gradients, however, remains a major roadblock for faithful prediction of El Niño's future changes.

Differential effects of chromosome and plasmid blaCTX-M-15 genes on antibiotic susceptibilities in extended-spectrum beta-lactamase-producing Escherichia coli isolates from patients with urinary tract infection.

OBJECTIVES: To compare antibiotic susceptibilities between chromosomal and plasmid blaCTX-M-15 locations in urinary tract infection-causing extended-spectrum ß-lactamases-producing Escherichia coli blaCTX-M-15 isolated in Indonesia. METHODS: A total of 84 strains identified as extended-spectrum ß-lactamases-producing E. coli were isolated from patients with urinary tract infection in Indonesia in 2015. Antimicrobial susceptibility tests were performed on these strains using 18 antibiotics, and extended-spectrum ß-lactamase bla genes were detected by polymerase chain reaction. Gene localization of blaCTX-M-15 -positive strains was confirmed by Southern blot hybridization, and epidemiological typing was conducted using multilocus sequence typing. RESULTS: Of 54 strains harboring the blaCTX-M-15 gene, 27 showed localization on chromosome, 20 on plasmid, and seven on chromosome and plasmid. Most multilocus sequence typing sequence types of the 27 strains with chromosomal blaCTX-M-15 were ST405 (25.9%) and ST131 (22.2%) strains, whereas the 20 strains with plasmid-blaCTX-M-15 were mostly ST410 (55.0%). CONCLUSIONS: Extended-spectrum ß-lactamases-producing E. coli blaCTX-M-15 with plasmid genes show significantly higher resistant rates against piperacillin-tazobactam but lower resistant rates against chloramphenicol compared to chromosomal strains in Indonesian patients with urinary tract infection. Mechanistic investigations will be necessary to advance our knowledge of antimicrobial resistance in urinary tract infection.

Establishment of an artificial urine model in vitro and rat or pig model in vivo to evaluate urinary crystal adherence.

The current study aimed to establish an experimental model in vitro and in vivo of urinary crystal deposition on the surface of ureteral stents, to evaluate the ability to prevent crystal adhesion. Non-treated ureteral stents were placed in artificial urine under various conditions in vitro. In vivo, ethylene glycol and hydroxyproline were administered orally to rats and pigs, and urinary crystals and urinary Ca were investigated by Inductively Coupled Plasma-Optical Emission Spectrometer. in vitro, during the 3- and 4-week immersion periods, more crystals adhered to the ureteral stent in artificial urine model 1 than the other artificial urine models (p < 0.01). Comparing the presence or absence of urea in the composition of the artificial urine, the artificial urine without urea showed less variability in pH change and more crystal adhesion (p < 0.05). Starting the experiment at pH 6.3 resulted in the highest amount of crystal adhesion to the ureteral stent (p < 0.05). In vivo, urinary crystals and urinary Ca increased in rat and pig experimental models. This experimental model in vitro and in vivo can be used to evaluate the ability to prevent crystal adhesion and deposition in the development of new ureteral stents to reduce ureteral stent-related side effects in patients.

Simple bio-inspired coating of ureteral stent for protein and bacterial fouling and calcium encrustation control.

Encrustation, caused by deposition of calcium and magnesium salts present in urine, is a common problem of indwelling urinary devices, such as ureteral stent. Encrustation was also found to be related to urinary tract infections; thus, it is necessary to prepare ureteral stents with antibacterial and antifouling surfaces to mitigate the occurrence of encrustation. In this study, commercial ureteral stent was coated with polydopamine (PDA), formed from self-polymerization of dopamine. The PDA coating was optimized in terms of dopamine concentration, pH, and coating time using response surface methodology. The chosen response parameters for optimization were calcium oxalate (CaC2 O4 ) encrustation and protein adsorption. Optimized PDA coating conditions were determined to be the following: pH 9.0, 2 mg/mL DA, and 3 days coating. The optimized PDA-coated ureteral stent exhibited outstanding resistance against CaC2 O4 encrustation, protein fouling, and bacterial adhesion due to its hydrophilic and functional coating layer. In comparison with the pristine ureteral stent, PDA coating was able to suppress approximately 97% and 87% of CaC2 O4 and protein adsorption, respectively. The PDA-coated ureteral stent was compared against those of commercially available ureteral stents and found to have superior encrustation and protein fouling mitigation performance. Finally, PDA coating was found to be highly stable for a storage period of 90 days, whether stored in wet or dry conditions.

Ocean fronts as decadal thermostats modulating continental warming hiatus.

Over the past decade, an unexpected cooling trend has been observed in East Asia and North America during winter. Climate model simulations suggest that this pattern of stalled warming, besides accelerated warming, will repeat throughout the course of global warming, influenced by the natural decade-long variations in the climate system. However, understanding the exact factors affecting the pace of warming remains a challenge. Here we show that a pause in warming over continental areas-namely, local warming hiatus-can be accompanied by excessive heat accumulation north of the ocean fronts. This oceanic condition, often manifesting in the form of marine heatwaves, constrains the subseasonal growth of atmospheric planetary waves, significantly increasing the likelihood of cold extremes in downstream continents. Our results underscore the importance of closely monitoring changing ocean fronts in response to human-induced warming, which can potentially reshape the inherent decade-long fluctuations within regional climates over the long term.

Growth and Migration Blocking Effect of Nanaomycin K, a Compound Produced by Streptomyces sp., on Prostate Cancer Cell Lines In Vitro and In Vivo.

Since castration-resistant prostate cancer (CRPC) acquires resistance to molecularly targeted drugs, discovering a class of drugs with different mechanisms of action is needed for more efficient treatment. In this study, we investigated the anti-tumor effects of nanaomycin K, derived from "Streptomyces rosa subsp. notoensis" OS-3966. The cell lines used were LNCaP (non-CRPC), PC-3 (CRPC), and TRAMP-C2 (CRPC). Experiments included cell proliferation analysis, wound healing analysis, and Western blotting. In addition, nanaomycin K was administered intratumorally to TRAMP-C2 carcinoma-bearing mice to assess effects on tumor growth. Furthermore, immuno-histochemistry staining was performed on excised tissues. Nanaomycin K suppressed cell proliferation in all cell lines (p < 0.001) and suppressed wound healing in TRAMP-C2 (p = 0.008). Nanaomycin K suppressed or showed a tendency to suppress the expression of N-cadherin, Vimentin, Slug, and Ras in all cell lines, and suppressed the phosphorylation of p38, SAPK/JNK, and Erk1/2 in LNCaP and TRAMP-C2. In vivo, nanaomycin K safely inhibited tumor growth (p = 0.001). In addition, suppression of phospho-Erk1/2 and increased expression of E-cadherin and cleaved-Caspase3 were observed in excised tumors. Nanaomycin K inhibits tumor growth and suppresses migration by inhibiting epithelial-mesenchymal transition in prostate cancer. Its mechanism of action is related to the inhibition of phosphorylation of the MAPK signaling pathway.

Increased Indian Ocean-North Atlantic Ocean warming chain under greenhouse warming.

Over the past half a century, both the Indian Ocean (IO) and the North Atlantic Ocean (NA) exhibit strong warming trends like a global mean surface temperature (SST). Here, we show that not only simply as a result of increased greenhouse gases, but the IO-NA interaction through atmospheric teleconnection boosts up their warming trends. Climate model simulations demonstrate that the IO warming increases the NA SST by enhancing the longwave radiation through atmospheric teleconnection, subsequently, the warmer NA SST-induced atmospheric teleconnection leads to IO warming by reducing evaporative cooling with weakened surface winds. This two-way interaction (i.e., IO-NA warming chain) acts as positive feedback that reinforces warming over both ocean basins. The Pacific Ocean is partly involved in this warming chain as a modulator in an interdecadal timescale. These results highlight the importance of understanding ocean-basin interactions that may provide a more accurate future projection of warming.

General circulation and global heat transport in a quadrupling CO2 pulse experiment.

To investigate the response of the general circulation and global transport of heat through both atmosphere and ocean to two-types of carbon dioxide removal scenario, we performed an earth system model experiment in which we imposed a pulse-type quadrupling of CO2 forcing for 50 years and a gradual peak-and-decline of four-time CO2 forcing. We found that the results from two experiments are qualitatively similar to each other. During the forcing-on period, a dominant warming in the upper troposphere over the tropics and on the surface at high latitudes led to a slowdown in the Hadley circulation, but the poleward atmospheric energy transport was enhanced due to an increase in specific humidity. This counteracted the reduction in poleward oceanic energy transport owing to the suppression of the meridional overturning circulation in both Hemispheres. After returning the original CO2 level, the hemispheric thermal contrast was reversed, causing a southward shift of the intertropical convergence zone. To reduce the hemispheric thermal contrast, the northward energy transports in the atmosphere and ocean surface were enhanced while further weakening of the global-scale Atlantic meridional overturning circulation led to southward energy transport in the deep ocean.

Correlation Between Changes in Syphilis Treatment and Jarisch-Herxheimer Reaction.

The number of syphilis patients has significantly increased recently in Japan and worldwide. Previous reports, even in large institutions, may not accurately reflect the current situation in urological clinics. We therefore collected data from 11 urological clinics in Hyogo Prefecture, Japan over a 2-year period subdivided into 1) August 2016 to July 2017 and 2) August 2017 to July 2018 to compare changes in syphilis consults. We analyzed the patient data including a rapid plasma reagin test (RPR), Treponema pallidum (TP) antibody, clinical stage, therapy, and presence of Jarisch-Herxheimer reaction. In total, 45 patients presented for a first consultation, 22 in the first year and 23 in the second year. Almost all patients were male. Initial consolidation and hard chancre were the major symptoms. RPR values and TP antibody values did not change. The treatment period with amoxicillin was significantly longer in the first year (p = 0.006). A Jarisch-Herxheimer reaction was seen in 13.6% in the first year and 60.9% in the second year (p = 0.001). The duration of antibiotic treatments was more likely to be based on the guidelines for antibiotic use in the second year, but Jarisch-Herxheimer reactions increased. Further follow-up including recurrent patients is necessary to draw definitive conclusions.

Comparison between antimicrobial stewardship program and intervention by infection control team for managing antibiotic use in neurogenic bladder-related urinary tract infection patients: A retrospective chart audit.

BACKGROUND: Antimicrobial prescriptions are relatively common in urologic outpatients. Therefore, it is necessary to investigate the impact of antimicrobial stewardship program (ASP) interventions. METHODS: In urology outpatients, antimicrobial use density (AUD), antimicrobial agent costs, isolation of urinary tract infection (UTI)-causing organisms and their antimicrobial susceptibilities were compared between intervention by infection control team (ICT) era (pre-2014) and ASP era (post-2014) in 2739 patients with lower urinary tract symptoms, including neurogenic bladder patients with UTI or suspected UTI, from 2011 to 2020. RESULTS: In the ASP, overall AUD (P<.001), cefotiam (CTM) (P=.0013), 2nd-generation cephalosporins (P=.026), cefdinir (CFDN) (P<.001), levofloxacin (LVFX) (P<.001), sitafloxacin (STFX) (P=.0016), and tosufloxacin (TFLX) (P=.0044) showed a significant decrease, but cefaclor (P=.019) showed a significant increase. Regarding antimicrobial agent costs, overall (P=.016), CTM (P=.021), 2nd-generation cephalosporins (P=.033), CFDN (P=.016), LVFX (P=.016), STFX (P=.033), and TFLX (P=.033) showed a significant decrease in the ASP. UTI-causing antimicrobial susceptibilities, CTM (P=.035), LVFX (P=.026) and sulfamethoxazole/trimethoprim (P=.048) in E. coli, and minocycline (P=.026) in K. pneumoniae showed a significant improve in the ASP. CONCLUSION: ASP contributed to decrease AUD and antimicrobial agent costs, and to improve antimicrobial susceptibilities of E. coli and K. pneumoniae to several antibiotics, compared to ICT. Further prospective studies are necessary for definitive conclusions.

Relevance of A Disintegrin and Metalloproteinase Domain-Containing (ADAM)9 Protein Expression to Bladder Cancer Malignancy.

We evaluated the effect of A Disintegrin and Metalloproteinase Domain-Containing (ADAM)9 protein on exacerbation in bladder cancer KK47 and T24. First, we knocked down ADAM9 and investigated cell proliferation, migration, cell cycle, and the epithelial-mesenchymal transition (EMT)-related proteins expression in vitro. We then investigated the expression level of ADAM9 in clinical urine cytology samples and the Cancer Genome Atlas (TCGA) data. Cell proliferation was significantly reduced in both cell lines after ADAM9 knockdown. In the cell-cycle assay, the percentage of G0/G1 cells was significantly increased in ADAM9 knockdown T24. Migration of T24 was more strongly suppressed than KK47. The expression level of EMT-related proteins suggested that EMT was suppressed in ADAM9 knockdown T24. TCGA analysis revealed that ADAM9 mRNA expression was significantly higher in stage IV and high-grade cancer than in other stages and low-grade cancer. Moreover, in the gene expression omnibus (GEO) study, bladder cancer with surrounding carcinoma and invasive carcinoma showed significantly high ADAM9 mRNA expression. We found that ADAM9 knockdown suppressed cell proliferation and migration in bladder cancer and that high-grade bladder cancer is correlated with higher expression of ADAM9.

Impact on quinolone resistance of plasmid-mediated quinolone resistance gene and mutations in quinolone resistance-determining regions in extended spectrum beta lactamase-producing Klebsiella pneumoniae isolated from urinary tract infection patients.

Klebsiella pneumoniae is a typical pathogen in urinary tract infections (UTI), and the emergence of extended spectrum beta-lactamase (ESBL)-producing strains has been frequently reported, accompanied by higher quinolone resistance rates. There are two major mechanisms of quinolone resistance, mutations in quinolone resistance-determining regions (QRDR) and the presence of the plasmid-mediated quinolone resistance (PMQR) genes. This study aimed to investigate quinolone resistance among 105 ESBL-producing K. pneumoniae specimens isolated from UTI patients in Indonesia. These were characterized for antimicrobial resistance to nalidixic acid, ciprofloxacin, and levofloxacin, QRDR mutations in gyrA and parC and the presence of PMQR genes. We found that 84.8% of the collected isolates were resistant to at least one of the quinolones. QRDR mutation in gyrA was observed in 49.5% of these strains and parC mutations in 61.0%. PMQR genes were identified in 84.8% of strains. The QRDR mutations clearly had a greater effect on resistance than the PMQR genes. In conclusion, we found high quinolone resistance rates in Indonesian ESBL-producing K. pneumoniae, in which QRDR mutation played a major role.

Mean sea surface temperature changes influence ENSO-related precipitation changes in the mid-latitudes.

El Niño profoundly impacts precipitation in high-population regions. This demands an advanced understanding of the changes in El Niño-induced precipitation under the future global warming scenario. However, thus far, consensus is lacking regarding future changes in mid-latitude precipitation influenced by El Niño. Here, by analyzing the Coupled Model Intercomparison Project simulations, we show that future precipitation changes are tightly linked to the response of each type of El Niño to the tropical Pacific mean sea surface temperature (SST) change. A La Niña-like mean SST change intensifies basin-wide El Niño events causing approximately 20% more precipitation over East Asia and North America via enhancing moisture transport. Meanwhile, an El Niño-like mean SST change generates more frequent eastern Pacific El Niño events, enhancing precipitation in North American. Our findings highlight the importance of the mean SST projection in selectively influencing the types of El Niño and their remote impact on precipitation.

Polymicrobial Solitary Retroperitoneal Abscess Due to Sigmoid Colon Perforation.

We treated an 85-year-old man with an abscess perforating into the retroperitoneal space from the sigmoid colon, with retroperitoneal drainage combined with antibiotics. CT showed no abscess formation in the intraperitoneal space. The patient consulted a doctor with a chief complaint of left-side low back pain and fever. He was first diagnosed with bacteremia due to Escherichia coli and close examination by CT revealed a retroperitoneal abscess. On referral to our hospital, we determined by CT that the cause of abscess formation was perforation of the intestine into the retroperitoneal space and spreading into the psoas muscle compartment. We then performed colostomy and abscess drainage through the retroperitoneal space to prevent the abscess disseminating into the intraperitoneal space. The abscess and necrotic tissue cultures were polymicrobial, including Enterobacteriaceae and Bacteroides spp. The abscess almost disappeared after drainage, and the patient's general condition gradually improved. The retroperitoneal abscess did not relapse by follow-up CT. In conclusion, this rare case presented with perforation of the intestine (Sigmoid colon) disseminated only to the retroperitoneal space without no intraperitoneal space abscess formation. We performed drainage only by a retroperitoneal approach without entering the intraperitoneal space.

The Antimicrobial Resistance Characteristics of Imipenem-Non-Susceptible, Imipenemase-6-Producing Escherichia coli.

Imipenemase-6 (IMP-6) type carbapenemase-producing Enterobacteriaceae is regarded as dangerous due to its unique lack of antimicrobial susceptibility. It is resistant to meropenem (MEPM) but susceptible to imipenem (IPM). In addition to carbapenemase, outer membrane porins and efflux pumps also play roles in carbapenem resistance by reducing the antimicrobial concentration inside cells. Extended-spectrum ß-lactamase (ESBL) is transmitted with IMP-6 by the plasmid and broadens the spectrum of antimicrobial resistance. We collected 42 strains of IMP-6-producing Escherichia coli and conducted a molecular analysis of carbapenemase, ESBL, porin, efflux, and epidemiological characteristics using plasmid replicon typing. Among the 42 isolates, 21 strains were susceptible to IPM (50.0%) and 1 (2.4%) to MEPM. Seventeen strains (40.5%) co-produced CTX-M-2 type ESBL. We found that the relative expression of ompC and ompF significantly correlated with the MIC of IPM (p = 0.01 and p = 0.03, respectively). Sixty-eight% of CTX-M-2-non-producing strains had IncI1, which was significantly different from CTX-M-2-producing strains (p < 0.001). In conclusion, 50.0% of our IMP-6-producing strains were non-susceptible to IPM, which is different from the typical pattern and can be attributed to decreased porin expression. Further studies investigating other types of carbapenemase are warranted.