Efficacy and safety of tedizolid for the treatment of ventilated gram-positive hospital-acquired or ventilator-associated bacterial pneumonia in Japanese patients: Results from a subgroup analysis of a phase 3, randomized, double-blind study comparing tedizolid and linezolid

INTRODUCTION

The results from the phase 3 study that evaluated the efficacy and safety of tedizolid phosphate, an oxazolidinone drug, for the treatment of gram-positive ventilated hospital-acquired bacterial pneumonia (vHABP)/ventilator-associated bacterial pneumonia (VABP) compared with linezolid (VITAL study), have been previously reported. We conducted a subgroup analysis to report the data obtained from Japanese patients enrolled in this study.

METHODS

Patients aged ≥18 years with vHABP/VABP likely to be caused by gram-positive cocci were randomized 1:1 to tedizolid phosphate 200 mg once daily for 7 days or linezolid 600 mg twice daily for 10 days. In both treatment groups, patients with concurrent gram-positive bacteremia were treated for 14 days. Primary efficacy endpoints were day 28 all-cause mortality (ACM) and investigator-assessed clinical response at test-of-cure (TOC) in the intention-to-treat population. Safety outcomes included assessment of treatment-emergent adverse events.

RESULTS

Fifty-three Japanese patients were randomized at received study drug (tedizolid, n = 28; linezolid, n = 25). Demographics and characteristics were generally similar between treatment groups. Rates of day 28 ACM were 10.7% and 20.0% with tedizolid and linezolid, respectively (difference, 9.3%; 95% CI, -10.1 to 28.7). Rates of investigator-assessed clinical cure at TOC were 78.6% and 72.0% with tedizolid and linezolid, respectively (difference, 6.6%; 95% CI, -16.7 to 29.8). Tedizolid phosphate was generally well tolerated and no new safety concerns were observed in the Japanese subgroup.

CONCLUSION

The results from this subgroup analysis suggest generally favorable efficacy and safety of tedizolid in adult Japanese patients with vHABP/VABP. (ClinicalTrials.gov identifier: NCT02019420).

Comprehensive Genomic Survey of Antimicrobial-Resistance Bacteria in the Sewage Tank Replacement with Hospital Relocation

Background

Excrement containing antimicrobial-resistant bacteria (ARB) is discharged from the hospital sewage through wastewater treatment plants (WWTP) into rivers, increasing the antimicrobial resistance (AMR) burden on the environment.

Purpose

We illustrate the contamination of hospital sewage tanks with ARB harboring antimicrobial resistance genes (ARGs) using comprehensive metagenomic sequencing. During the study period, we moved to a new hospital building constructed for renovation. Therefore, we investigated the difference in bacterial flora in the sewage tanks for each building with different departments, and the change in bacterial flora over time in new sewage tanks. Furthermore, we performed a comparative genome analysis of extended spectrum β-lactamase (ESBL)-producing organisms (EPOs) from hospital sewage and clinical samples. Residual antibiotics in the sewage tank were also measured.

Methods

Metagenomic analysis was performed on the hospital sewage samples, followed by whole genome sequencing of EPOs.

Results

The bacterial composition of new sewage tanks was comparable with that of old tanks within 1 month after relocation and was instantly affected by excrement. The bacterial composition of sewage tanks in the old and new buildings, containing rooms where seriously ill patients were treated, was similar. Selection on CHROMagar ESBL allowed detection of EPOs harboring bla_CTX-M and carbapenemase genes in all sewage tanks. One of the sewage Escherichia coli strain comprising ST393 harboring bla_CTX-M-27 corresponded to the clinical isolates based on core genome analysis. Moreover, the levels of levofloxacin and clarithromycin in the hospital sewage were 0.0325 and 0.0135 µg/mL, respectively.

Conclusion

Hospital sewage was contaminated with many ARB species, ARGs and residual antibiotics, which can cause a burden on WWTP sewage treatment. The bacterial flora in the sewage tank was rapidly affected, especially by the ward with seriously ill patients. AMR monitoring of hospital sewage may help detect carriers prior to nosocomial ARB-associated outbreaks and control the outbreaks.

Change in antimicrobial susceptibility of pathogens isolated from surgical site infections over the past decade in Japanese nation-wide surveillance study

Inappropriate antimicrobial therapy for surgical site infections (SSIs) can lead to poor outcomes and an increased risk of antibiotic resistance. A nationwide survey was conducted in Japan from 2018 to 2019 to investigate the antimicrobial susceptibility of pathogens isolated from SSIs. The data were compared with those obtained in 2010 and 2014-2015 surveillance studies. Although the rate of detection of extended-spectrum β-lactamase producing strains of Escherichia coli was increased from 9.5% in 2010 to 23% in 2014-2015, the incidence decreased to 8.7% in 2018-2019. Although high susceptibility rates were detected to piperacillin/tazobactam (TAZ), the geometric mean MICs were substantially higher than to meropenem (2.67 vs 0.08 μg/mL). By contrast, relatively low geometric mean MICs (0.397 μg/mL) were demonstrated for ceftolozane/TAZ. Although the MRSA incidence rate decreased from 72% in the first surveillance to 53% in the second, no further decrease was detected in 2018-2019. For the Bacteroides fragilis group species, low levels of susceptibility were observed for moxifloxacin (65.3%), cefoxitin (65.3%), and clindamycin (CLDM) (38.9%). In particular, low susceptibility against cefoxitin was demonstrated in non-fragilis Bacteroides, especially B. thetaiotaomicron. By contrast, low susceptibility rates against CLDM were demonstrated in both B. fragilis and non-fragilis Bacteroides species, and a steady decrease in susceptibility throughout was observed (59.3% in 2010, 46.9% in 2014-2015, and 38.9% in 2018-2019). In conclusion, Japanese surveillance data revealed no significant lowering of antibiotic susceptibility over the past decade in organisms commonly associated from SSIs, with the exception of the B. fragilis group.

878. Antimicrobial Susceptibility of Pathogens Isolated from Surgical Site Infections in Japan: Comparison of Data from Nationwide Surveillance Studies Conducted in 2010, 2014–2015 and 2018-2019

Background

A nationwide survey was conducted in Japan from 2018–2019 to investigate the antimicrobial susceptibility of pathogens isolated from surgical site infections (SSI).

Methods

The resulting data were compared with that obtained in earlier surveys, conducted in 2010, 2014–2015, and 2018-2019.

Results

Seven main organisms were collected, and in total 2081 isolates were studied. Although a significant increase of extended-spectrum β-lactamase (ESBL) producing organisms among Enterobacteriaceae was demonstrated in 2014–15 (13.5%) compared with 2010 (5.3%), the incidence remained 6.6% in 2018–19. Only one carbapenemase-producing Enterobacteriaceae isolates were identified in the 2018–2019 study. The geometric mean (GM) MICs for ESBL producing isolates in 2018–2019 were 0.08 µg/mL for meropenem, 2.67 µg/mL for tazobactam/piperacillin, 0.40 µg/mL for tazobactam/ceftolozane, 6.35 µg/mL for cefoxitin, and 1.12 µg/mL for gentamycin. Antibiotic susceptible rate in Pseudomonas aeruginosa was 95.5% in meropenem, 93.9% in piperacillin/tazobactam, 100% in tazobactam/ceftolozane, 97.0% in cefepime, 90.9% in ciprofloxacin, and 86.4% in gentamycin. There was no significant difference in methicillin resistance rate of Staphylococcus aureus isolates among 3 study periods (72.0% in 2010, 53.4% in 2014–2015, and 63% in 2018-19). MRSA isolates with a vancomycin MIC of 2μg/mL accounted for 9.7% in 2010, 1.2% in 2014–2015, and 3.1% in 2018-19. GM MICs for MRSA isolates were 2.09 µg/mL for linezolid, 0.32 µg/mL for tedizolid, and 0.61 µg/mL for daptomycin. GM MICs in linezolid and daptomycin for the isolates in 2018–19 tended to be increased compared with isolates in 2010 (1.74 to 2.09 and 0.35 to 0.61 µg/mL, respectively). More than 90% of isolates belonging to the Bacteroides fragilis group remained susceptible to tazobactam/piperacillin, meropenem, and metronidazole. In contrast, lower levels of susceptibility were observed for moxifloxacin (65.3%), cefmetazole (47.2%) and clindamycin (38.9%). In cefoxitin, non-fragilis Bacteroides isolates had lower rates of antibiotic susceptibility compared with B. fragilis. (51.3% vs. 81.8%).

Conclusion

Overall, the surveillance data clarified trends in antimicrobial susceptibility for organisms commonly associated with SSI.

Disclosures

Yoshio Takesue, M.D, Ph.D, Astellas Pharma Inc (Speaker’s Bureau)MSD Japan (Speaker’s Bureau)Sumitomo Dainippon Pharma Co. Ltd. (Grant/Research Support) Hiroshige Mikamo, M.D, Ph.D, Astellas Pharma Inc. (Grant/Research Support, Speaker’s Bureau)MSD Japan (Grant/Research Support, Speaker’s Bureau)Pfizer Japan Inc. (Grant/Research Support)Sumitomo Dainippon Pharma Co., Ltd (Grant/Research Support, Speaker’s Bureau)

Association of Respiratory Tract Infection after Gastroenterological Surgery with Postoperative Duration of Hospitalization and Medical Expenses: Subanalysis of Data from a Multicenter Study

BACKGROUND

Postoperative infections can be classified as surgical site infections and remote infections. Postoperative respiratory tract infections (PRTI) are a type of remote infection and may be associated with prolonged hospitalization and increased medical expenses. This study compared postoperative duration of hospitalization and medical expenses between patients with and without PRTI after gastrointestinal surgery.

METHODS

We retrospectively analyzed data from a multicenter study of centers affiliated with the Japan Society for Surgical Infection and used 1-to-1 matching analysis to evaluate 86 patients who underwent gastrointestinal surgery during the period from March 1, 2014 through February 29, 2016.

RESULTS

Duration of postoperative hospitalization was significantly longer for patients with PRTI (38.6 days) than for those without PRTI (16.1 days), and postoperative medical expenses were significantly higher for patients with PRTI (1388.2 USD) than for those without PRTI (629.4 USD).

CONCLUSIONS

Duration of hospitalization is longer and medical expenses are higher for patients that develop surgical site infections. This study found that this was also the case for patients with PRTI after gastrointestinal surgery. However, further studies are needed in order to confirm these results.

Impact of postoperative remote infection on length of stay and medical costs in hospitals in Japan

PURPOSE

To analyze the impact of postoperative remote infections (PRIs) on medical expenditure.

METHODS

The subjects of this retrospective study were 338 patients who had undergone gastroenterological surgery at one of the 20 Japanese institutions within the Japan Society for Surgical Infection (JSSI) and mainly authorized as educational institutions. The patients were allocated to 169 pairs of those with a PRI (PRI (+) group) matched with those without a PRI (PRI (-) group). PRIs included pneumonia, urinary tract infection (UTI), catheter-associated blood stream infection (CA-BSI), and antibiotic-associated enteritis.

RESULTS

SSI developed in 74 of the 338 patients (22 without PRI and 52 with PRI). The SSI incidence was significantly higher in the PRI (+) group (p < 0.001). The difference in the median postoperative length of hospital stay was 15 days, indicating a significant prolongation in the PRI (+) group (p < 0.001). The PRI (+) group also had a higher rate of inter-hospital transfer (p < 0.01) and mortality (p < 0.001). Similarly, the difference in median postoperative medical fees was $6832.3, representing a significant increase in the PRI (+) group (p < 0.001).

CONCLUSIONS

The postoperative length of hospital stay is longer and the postoperative medical expenditure is higher for patients with a PRI than for those without a PRI.

Superior outcomes (but at higher costs) of non-operative management with interval appendectomy over immediate surgery in appendicitis with abscess: Results from a large adult population cohort

INTRODUCTION

The aim of this study was to compare surgical outcomes and hospitalization costs between immediate surgery and non-operative management followed by interval appendectomy in adults presenting with appendicitis with abscess.

METHODS

From 2003 to 2015, 3316 patients presented with appendicitis, including 101 who presented with appendicular abscess. Between 2003 and 2006, 33 patients with appendicular abscess were managed with emergency operations (emergency group). Non-operative management followed by interval appendectomy was implemented in 2007 and offered to 68 patients during the study period. Of these patients, 64 patients underwent the procedure (interval group), and 4 patients refused.

RESULTS

Non-operative management was successful in 76.6% of cases (49/64 patients) in the interval group. Operative time and length of hospital stay were similar between the emergency and interval groups. In the interval group, blood loss, the need for extended resection, and overall postoperative morbidity were significantly lower than in the emergency group (P < 0.01, respectively). Medical costs for surgery in the interval group were lower than in the emergency group ($4512 vs $6888, P = 0.002), but this group's total medical costs were higher ($9591 vs $6888, P < 0.01).

CONCLUSION

The interval strategy is associated with a reduced need for extended resection, lower postoperative morbidity, and a shorter length of hospital stay. However, total medical costs for the interval strategy are higher than those for emergency operations in cases of appendicular abscess in adults.

Postoperative Infection after Colorectal Surgery: Subanalysis of Data from the 2015 Japan Postoperative Infectious Complications Survey

BACKGROUND

Most surveillance programs for postoperative infection focus on surgical site infections (SSI). However, postoperative remote infections are of emerging clinical importance. Using data from a multicenter survey administered to patients who underwent gastrointestinal surgery, we investigated the incidence of SSI and remote infection after colorectal surgery.

METHODS

From September 2015 through March 2016, 1,724 patients underwent colorectal surgery in 28 affiliated centers in Japan. We retrospectively recorded patient age, sex, surgical site, surgical approach, wound classification, performance status at discharge, and postoperative infection status.

RESULTS

Postoperative infection was noted in 236 (13.7%) patients; 150 and 86 patients underwent colon and rectal surgeries, respectively (incidence of postoperative infection: 13.7% and 14.8%). The incidence of postoperative infection was significantly lower after laparoscopic surgery than after open surgery, in colon and rectal surgery (p < 0.001). Among patients with postoperative infections, 211 (89.4%) had a single infection and 25 (10.6%) had multiple infections. Among patients with a single postoperative infection, SSI and remote infection occurred in 143 (60.6%) and 68 (28.8%) patients, respectively. The most common multiple postoperative infections were "incisional and organ/space SSIs" and "organ/space SSI and bacteremia of unknown origin" (n = 3 each).

CONCLUSIONS

This study revealed the prevalence distributions for postoperative SSI and remote infections. Because of the substantial effect of remote infections on patient quality of life and the associated social burden, prospective periodic surveillance for SSI and remote infection is necessary for careful evaluation and prevention.

Successful perioperative infection control measures after gastroenterological surgery reduced the number of cases of methicillin-resistant Staphylococcus aureus or Clostridioides (Clostridium) difficile infection to almost zero over a 30-year period: a single-department experience

PURPOSE

To investigate changes in the incidence of postoperative infections in the surgical department of a teaching hospital.

METHODS

During the 30-year period from September 1987 to August 2017, 11,568 gastroenterological surgical procedures were performed in our surgical department. This 30-year period was divided into seven periods (A-G), ranging from 2 to 7 years each and based on the infection control methods used in each period. We then compared the rates of incisional surgical site infection (SSI) and organ/space SSI; remote infection (RI) including respiratory tract infection (RTI), intravascular catheter-related infection, and urinary tract infection (UTI); and antibiotic-associated colitis caused by methicillin-resistant Staphylococcus aureus (MRSA) enteritis or Clostridioides (Clostridium) difficile-associated disease (CDAD) among the seven periods.

RESULTS

In periods B (September 1990-August 1997) and E (November 2004-July 2007), when a unique antibiotic therapy devised in our department was in use, MRSA was isolated from only 0.3% and 0.4% of surgical patients, respectively, and these rates were significantly lower than those in the other periods (p < 0.05). The rate of CDAD increased during period F (August 2007-July 2014), but in period G (August 2014-August 2017), restrictions were placed on the use of antibiotics with a strong anti-anaerobic action and, in this period, the rate of CDAD was only 0.04%, which was significantly lower than that in period F (p < 0.05).

CONCLUSIONS

Limiting the use of antibiotics that tend to disrupt the intestinal flora may reduce the rates of MRSA infection and CDAD after gastroenterological surgery.

Current status of post-operative infections due to antimicrobial-resistant bacteria after digestive tract surgery in Japan: Japan Postoperative Infectious Complications Survey in 2015 (JPICS'15)

PURPOSE

We herein report the findings of the Japan Postoperative Infectious Complication Survey in 2015 (JPICS'15), which evaluated the rate of post-operative infections and colonization due to antimicrobial-resistant (AMR) bacteria after digestive tract surgery.

METHODS

This survey by the Japan Society of Surgical Infection included patients undergoing digestive tract surgery at 28 centers between September 2015 and March 2016. Data included patient background characteristics, type of surgery, contamination status, and type of post-operative infections, including surgical site infections (SSIs), remote infections (RIs), and colonization.

RESULTS

During the study period, 7,565 surgeries (of 896 types) were performed; among them, 905 cases demonstrated bacteria after digestive tract surgery. The survey revealed that post-operative infections or colonization by AMR bacteria occurred in 0.9% of the patient cohort, constituting 7.5% of post-operative infections, including 5.6% of SSIs and 1.8% of RIs. Extended-spectrum β-lactamase-producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus were the predominant AMR bacteria isolated from patients after digestive tract surgery. Patients infected with AMR bacteria had a poor prognosis.

CONCLUSION

Our results reveal that 7.5% of the post-operative infections were due to AMR bacteria, indicating the need for antibacterial coverage against AMR bacteria in patients with critical post-operative infections.

Current status of postoperative infections after digestive surgery in Japan: The Japan Postoperative Infectious Complications Survey in 2015

AIM

To survey postoperative infections (PI) after digestive surgery.

METHODS

This survey, conducted by the Japan Society of Surgical Infection, included patients undergoing digestive surgery at 28 centers between September 2015 and March 2016. Data collected included patient background characteristics, type of surgery, contamination status, and type of PI, including surgical site infection (SSI), remote infection (RI), and antimicrobial-resistant (AMR) bacterial infections and colonization.

RESULTS

Postoperative infections occurred in 10.7% of 6582 patients who underwent digestive surgery (6.8% for endoscopic surgery and 18.7% for open surgery). SSI and RI, including respiratory tract infection, urinary tract infection, antibiotic-associated diarrhea, drain infection, and catheter-related bloodstream infection, occurred in 8.9% and 3.7% of patients, respectively. Among all PI, 13.2% were overlapping infections. The most common overlapping infections were incisional and organ/space SSI, which occurred in 4.2% of patients. AMR bacterial infections occurred in 1.2% of patients after digestive surgery and comprised 11.5% of all PI. Rate of AMR bacterial colonization after digestive surgery was only 0.3%.

CONCLUSION

Periodic surveillance of PI, including AMR bacteria, is necessary for a detailed evaluation of nosocomial infections.

Prospective short-term feasibility study of perioperative suprapubic catheters in laparoscopic colectomy

INTRODUCTION

Here we report a prospective study on whether a temporary suprapubic catheter (SPC) can be safely inserted as a substitute for transurethral balloon catheterization during laparoscopy-assisted colectomy.

METHODS

Our subjects included 52 cases who gave informed consent to have an SPC inserted. These subjects were selected from cases who underwent laparoscopy-assisted surgery for primary colorectal cancer from October 2014 to August 2015.

RESULTS

An SPC was inserted into 45 of the original 52 cases. The median surgical duration was 220 min (range, 11-438 min), and the SPC insertion was performed at a median of 133 min (range, 9-384 min) after the start of surgery. Insertion required a median duration of 116 s. In one case (2.2%), the bladder was perforated by the paracentesis needle, and in two cases (4.4%), hematuria was observed at the time of insertion; however, surgery was completed without any incident in these three cases. Six of the remaining 42 cases (13.3%) demonstrated neither micturition desire nor independent urination on the day the catheter was clamped. In these cases, the clamp was released two to four times, and draining of an average of 586-mL urine, micturition desire, and independent urination were confirmed 2-4 days later.

CONCLUSION

Transurethral balloon catheterization is a simple procedure that is commonly used on surgical patients, but it can cause pain, discomfort, and infection. In contrast, SPC insertion is a procedure that avoids crossing the urethra and its associated disadvantages. Here we were able to demonstrate that the procedure can be safely used in laparoscopic surgery patients.

[Carcinosarcoma of the Esophagus That Presented as Esophageal Stenosis]

Esophageal carcinosarcoma is a rare malignant tumor. A 76-year-old man consulted near hospital about dysphagia. A gastrointestinal fiberscopy showed a stricture of the thoracic esophagus at approximately 34 cm from the incisor, and the macroscopic type of the tumor was 0-Ip. Biopsy results indicated carcinosarcoma. The patient underwent esophagectomy and regional lymphadenectomy with gastric tube reconstruction by laparoscopy-assisted surgery and thoracotomy. Pathological examination of the surgical specimen revealed that the majority of the tumor was composed of spindle-shaped atypical cells, but because a very small transitional area between squamous cell carcinoma and sarcoma was noted, a diagnosis of carcinosarcoma was made. The depth of invasion was small, and no region lymph node metastasis was detected. We classified the tumor as pT1b(SM)N0M0, pStage I. Immunohistochemically, the spindle-shaped sarcomatous cells displayed a posi- tive reaction to vimentin and cytokeratin AE1/AE3. Ki -67(MIB-1)labeling index was high. The patient was discharged after an uneventful postoperative course and remains well as an outpatient at his 6-month follow-up. We report this case with a review of the literature.

[A Case of Advanced Gastric Cancer with Ptosis Caused by Orbital Metastasis]

Orbital metastasis of gastric cancer occurs very rarely.A 76-year-old woman, who consulted another doctor with the chief complaints of palpitation, shortness of breath, and anorexia 1 month previously, was referred to our clinic for workup and treatment.Workup revealed type III advanced gastric cancer at the lesser curvature of the gastric antrum.Biopsy revealed a diagnosis of poorly differentiated adenocarcinoma.As computed tomography suggested periaortic lymph node metastasis, a diagnosis of T4a(SE)N3aM1(LYM), cStage IV was made.Two weeks later, ptosis was observed in the right eye, and positron emission tomography-computed tomography(PET-CT)revealed metastasis to the right superior rectus muscle.No intracranial tumor progression was observed.The Cyberknife system(20 Gy/1 Fr)was used for treating the orbital tumor. Increased LYM was observed even after 2 courses of S-1 plus oxaliplatin(SOX)therapy.Therefore, weekly combination therapy of paclitaxel and ramucirumab(wPTX plus Rmab)was administered as second-line therapy.No new distal metastasis has been detected in the 10 months since the orbital metastasis development, and the patient is still alive.

Efficacy and safety of fidaxomicin for the treatment of Clostridioides (Clostridium) difficile infection in a randomized, double-blind, comparative Phase III study in Japan

We assessed the efficacy and safety of fidaxomicin, a narrow-spectrum macrocyclic antibiotic, for treating inpatients with Clostridioides (Clostridium) difficile infection (CDI) in Japan. The objective was to demonstrate the non-inferior efficacy of fidaxomicin versus vancomycin. This Phase III, vancomycin-controlled, double-blind, parallel-group study enrolled adults with CDI. Patients were randomly assigned to receive fidaxomicin (200 mg twice daily, orally) or vancomycin (125 mg four-times daily, orally) for 10 days. The primary endpoint was global cure rate of CDI (proportion of patients cured at end of treatment with no recurrence during 28-day follow-up). Non-inferiority margin of 10% was pre-specified. Two-hundred and twelve patients were randomized and received treatment at 82 hospitals. Global cure rate was 67.3% (70/104) with fidaxomicin and 65.7% (71/108) with vancomycin: difference 1.2% [95% confidence interval (CI) -11.3-13.7]. Non-inferiority was not demonstrated. Post-hoc analysis in full analysis set patients who received at least 3 days' treatment revealed a higher global cure rate for fidaxomicin [70/97 (72.2%)] than vancomycin [71/106 (67.0%)]: difference 4.6% (95% CI -7.9-17.1). Recurrence rate in the full analysis set for recurrence was lower in fidaxomicin- [17/87 (19.5%)] than vancomycin-treated [24/95 (25.3%)] patients. Adverse event incidences and profiles were similar for both treatments. Though non-inferiority was not demonstrated for fidaxomicin versus vancomycin, global cure rate was numerically higher and recurrence rate lower for fidaxomicin than vancomycin. Fidaxomicin could be an option for the treatment of CDI in an era of reduced antibiotic susceptibility, and to reduce the incidence of recurrence in Japanese patients. CLINICALTRIALS.

GOV IDENTIFIER

NCT02179658.

Antimicrobial susceptibility of common pathogens isolated from postoperative intra-abdominal infections in Japan

The principle of empirical therapy for patients with intra-abdominal infections (IAI) should include antibiotics with activity against Enterobacteriaceae and Bacteroides fragilis group species. Coverage of Pseudomonas aeruginosa, Enterobacter cloacae, and Enterococcus faecalis is also recommended for hospital-associated IAI. A nationwide survey was conducted to investigate the antimicrobial susceptibility of pathogens isolated from postoperative IAI. All 504 isolates were collected at 26 institutions and referred to a central laboratory for susceptibility testing. Lower susceptibility rates to ciprofloxacin and cefepime were demonstrated in Escherichia coli. Among E. coli, 24.1% of strains produced extended-spectrum β-lactamase (ESBL). Carbapenems, piperacillin/tazobactam, cephamycins/oxacephem, aminoglycosides, and tigecycline had high activity against E. coli, including ESBL-producing isolates. Among E. cloacae, low susceptibility rates to ceftazidime were demonstrated, whereas cefepime retained its activity. P. aeruginosa revealed high susceptibility rates to all antimicrobials tested except for imipenem. Among B. fragilis group species, low levels of susceptibility were observed for cefoxitin, moxifloxacin, and clindamycin, and high susceptibility rates were observed for piperacillin/tazobactam, meropenem, and metronidazole. Ampicillin, piperacillin, and glycopeptides had good activity against E. faecalis. Imipenem had the highest activity against E. faecalis among carbapenems. In conclusion, we suggested the empirical use of antimicrobials with the specific intent of covering the main organisms isolated from postoperative IAI. Piperacillin/tazobactam, meropenem, or doripenem, are appropriate in critically ill patients. Combination therapy of cefepime (aztreonam in patients with β-lactam allergy) plus metronidazole plus glycopeptides, imipenem/cilastatin or cephamycins/oxacephem plus ciprofloxacin plus metronidazole are potential therapeutic options.

Evaluating the timing of laparoscopic cholecystectomy for acute cholecystitis in an experienced center based on propensity score matching

INTRODUCTION

This study evaluates the therapeutic outcomes for laparoscopic cholecystectomy for acute cholecystitis based on the time from symptom onset to surgery.

METHODS

This study enrolled 224 patients. Patients' characteristics and operative outcomes were compared between patient groups based on the timing of laparoscopic cholecystectomy from symptom onset: ≤72 h versus >72 h, and ≤7 days versus ≥8 days. Then, we performed propensity score matching of 13 relevant variables, including patient demographics, examination findings, and therapeutic factors.

RESULTS

The early surgery groups (≤72 h and ≤7 days) had significantly younger patients with fewer comorbidities and a shorter duration from symptom onset to presentation before performed propensity score matching. These groups also had shorter surgery, postoperative hospital stay, and total length of stay. Other operative outcomes, including blood loss, conversion to open surgery, bile duct injury, and postoperative complications, did not significantly differ among the groups. After propensity score matching, all therapeutic outcomes, including duration of surgery, showed no significant differences in either analysis.

CONCLUSIONS

In a center with sufficient experience, performing laparoscopic cholecystectomy at the earliest possible time after presentation was a safe therapeutic strategy for each patient with acute cholecystitis, regardless of the time from symptom onset.

Comprehensive Diagnosis of Bacterial Infection Associated with Acute Cholecystitis Using Metagenomic Approach

Acute cholecystitis (AC), which is strongly associated with retrograde bacterial infection, is an inflammatory disease that can be fatal if inappropriately treated. Currently, bacterial culture testing, which is basically recommended to detect the etiological agent, is a time-consuming (4–6 days), non-comprehensive approach. To rapidly detect a potential pathogen and predict its antimicrobial susceptibility, we undertook a metagenomic approach to characterize the bacterial infection associated with AC. Six patients (P1–P6) who underwent cholecystectomy for AC were enrolled in this study. Metagenome analysis demonstrated possible single or multiple bacterial infections in four patients (P1, P2, P3, and P4) with 24-h experimental procedures; in addition, the CTX-M extended-spectrum ß-lactamase (ESBL) gene was identified in two bile samples (P1 and P4). Further whole genome sequencing of Escherichia coli isolates suggested that CTX-M-27-producing ST131 and CTX-M-14-producing novel-ST were identified in P1 and P4, respectively. Metagenome analysis of feces and saliva also suggested some imbalance in the microbiota for more comprehensive assessment of patients with AC. In conclusion, metagenome analysis was useful for rapid bacterial diagnostics, including assessing potential antimicrobial susceptibility, in patients with AC.

Antimicrobial susceptibility of pathogens isolated from surgical site infections in Japan: Comparison of data from nationwide surveillance studies conducted in 2010 and 2014-2015

A nationwide survey was conducted in Japan from 2014 to 2015 to investigate the antimicrobial susceptibility of pathogens isolated from surgical site infections (SSI). The resulting data were compared with that obtained in an earlier survey, conducted in 2010. Seven main organisms were collected, and 883 isolates were studied. A significant reduction in methicillin resistance was observed among Staphylococcus aureus isolates, dropping from 72.5% in 2010 to 53.8% in 2014-2015 (p < 0.001). MRSA isolates with a vancomycin minimum inhibitory concentration (MIC) of 2 μg/mL accounted for 1.2% of all MRSA isolates, which was significantly lower than in 2010 (9.7%, p = 0.029). Of the Escherichia coli isolates, 23.0% produced an extended spectrum β-lactamase (ESBL) in the 2014-2015 survey, which was a significant increase from 9.5% in 2010 (p = 0.011). The geometric mean MICs for ESBL-producing isolates were 0.07 μg/mL for meropenem, 9.51 μg/mL for tazobactam/piperacillin, 0.15 μg/mL for flomoxef, and 1.56 μg/mL for gentamycin. There was a significant increase in the isolation rate of non-fragilis Bacteroides among Bacteroides fragilis group species between the two study periods (35.2% vs. 53.1%, p = 0.007). More than 90% of isolates belonging to the B. fragilis group remained susceptible to tazobactam/piperacillin, meropenem, and metronidazole. In contrast, lower levels of susceptibility were observed for cefmetazole (49.6%), moxifloxacin (61.9%), and clindamycin (46.9%). Non-fragilis Bacteroides isolates had lower rates of antibiotic susceptibility compared with B. fragilis. Overall, the surveillance data clarified trends in antimicrobial susceptibility for organisms commonly associated with SSI.

Neutrophil/lymphocyte ratio has a prognostic value for patients with terminal cancer

Background

Determining prognosis in advanced cancer is of key importance. Various prognostic scores have been developed. However, they are often very complex. In this study, we evaluated the feasibility of neutrophil/lymphocyte ratio (NLR) as an index to estimate survival in terminal cancer patients.

Methods

NLR was calculated retrospectively based on blood tests performed at 3 months, 2 months, 4 weeks, 3 weeks, 2 weeks, 1 week, and within 3 days before death in 160 cancer patients (82 men, 78 women; age range, 33–99 years; mean age, 69.8 years).

Results

NLR increased significantly with time (P < 0.0001). Mean NLR was significantly higher in patients who died within 4 weeks (29.82) than in those who lived more than 4 weeks (6.15). The NLR cutoff point was set at 9.21 according to receiver operating characteristic curve analysis (area under the curve, 0.82; 95 % confidence interval, 0.79–0.85). We inferred that life expectancy would be <4 weeks when NLR >9.21. The sensitivity, specificity, positive predictive value, and negative predictive value were 65.6, 84.1, 90.6, and 51.1 %, respectively. The positive and negative likelihood ratios were 4.125 and 0.409, respectively.

Conclusions

NLR appears to be a useful and simple parameter to predict the clinical outcomes of patients with terminal cancer.

[SURVEILLANCE OF PERIOPERATIVE INFECTIONS AND INFECTION CONTROL]

Postoperative infections are classified into surgical site infections and remote infections. The risk factors associated with postoperative infections are related to medical practice, the patient, and bacteria. Postoperative infections not only prolong hospitalizations and increase patient burden but also affect prognosis. It is therefore important to conduct surveillance of postoperative complications at each facility to elucidate the risk factors for infection and to implement and evaluate infection control measures. Moreover, with the aging of the population, more surgeries are being performed in elderly individuals. However, the elderly tend to have age-related declines in the function of major organs as well as comorbidities, and surgeries in them carry a high risk despite advances in operative techniques and perioperative management. It is therefore important to determine surgical indications carefully by sufficiently assessing the risk preoperatively and performing appropriate perioperative management.

Open surgery versus laparoscopic surgery after stent insertion for obstructive colorectal cancer

PURPOSE

To compare the outcomes of laparoscopic surgery vs. open surgery after insertion of a colonic stent for obstructive colorectal cancer.

METHODS

Between April 2005 and August 2013, 58 patients underwent surgery after the insertion of a colonic stent for obstructive colorectal cancer. We analyzed the outcomes of the patients who underwent laparoscopic surgery vs. those who underwent open surgery.

RESULTS

We compared blood loss, operative time, hospital stay, and complications in 26 patients who underwent laparoscopic surgery and 32 patients who underwent open surgery. Blood loss was significantly less in the laparoscopic surgery group, but operative time was significantly shorter in the open surgery group. The length of hospital stay was shorter in the laparoscopic surgery group than in the open surgery group, but the difference was not significant. There was no significant difference in postoperative surgical complications between the groups.

CONCLUSION

The patients who underwent laparoscopic resection had less blood loss, although no significant difference was found in postoperative morbidity or mortality. Thus, laparoscopic resection after stent insertion is a feasible and safe option for patients with obstructive colorectal cancer.

Long-term and perioperative outcomes of laparoscopic versus open liver resection for colorectal liver metastases with propensity score matching: a multi-institutional Japanese study

BACKGROUND

The aim of the present study was to clarify the surgical outcome and long-term prognosis of laparoscopic liver resection (LLR) compared with conventional open liver resection (OLR) in patients with colorectal liver metastases (CRLM).

METHODS

A one-to-two propensity score matching (PSM) analysis was applied. Covariates (P < 0.2) used for PSM estimation included preoperative levels of CEA and CA19-9; primary tumor differentiation; primary pathological lymph node metastasis; number, size, location, and distribution of CRLM; existence of extrahepatic metastasis; extent of hepatic resection; total bilirubin and prothrombin activity levels; and preoperative chemotherapy. Perioperative data and long-term survival were compared.

RESULTS

From 2005 to 2010, 1,331 patients with hepatic resection for CRLM were enrolled. By PSM, 171 LLR and 342 OLR patients showed similar preoperative clinical characteristics. Median estimated blood loss (163 g vs 415 g, P < 0.001) and median postoperative hospital stay (12 days vs 14 days; P < 0.001) were significantly reduced in the LLR group. Morbidity and mortality were similar. Five-year rates of recurrence-free, overall, and disease-specific survival did not differ significantly. The R0 resection rate was similar.

CONCLUSIONS

In selected CRLM patients, LLR is strongly associated with lower blood loss and shorter hospital stay and has equivalent long-term survival comparable with OLR.

The treatment for unresectable advanced gastric cancer with pyloric stenosis

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Background: Inability of oral intake due to advanced gastric cancer with pyloric stenosis (AGCPS) should be avoided, because the key drug of chemotherapy for gastric cancer is S-1 in Japan. We have performed palliative gastrectomy (PG), gastrojejunostomy (GJ) or stent placement (SP) for unresectable AGCPS. We investigated therapeutic outcomes (gastric outlet obstruction scoring system: GOOSS, chemotherapy introduction rate: CIR and median survival time: MST) of each therapy retrospectively. Methods: Between April 1999 and April 2013, 42 patients with unresectable AGCPS were included in this study (PG/GJ/SP, 13/10/19). We compared therapeutic outcomes (GOOSS, CIR and MST) between the 3 groups. Results: The demographic characteristics of patients were similar across the three groups. We evaluated the Glasgow Prognostic Score (GPS) of all cases before treatment. GPS tended to be 1 in the PG group, 0 in the GJ group and 2 in the SP group. The proportion of GPS 2 in the SP group was higher than in PG or GJ group significantly (p=0.0056 for SP vs. PG, p=0.0191 for SP vs. GJ and p=0.007 for SP vs. Surgery). GOOSS scores of all patients were improved. GOOSS score 3 of PG/GJ/SP groups after treatment were 84.6 / 90 / 68.4% respectively. CIR, MST and post-operative complication rate of PG/GJ/SP groups were 53.8 / 90 / 42.1%, 222.5 / 435.5 / 74 days and 46.2 / 10 / 0%, respectively. The proportion of patients receiving chemotherapy was higher in the GJ group than in the PG group, and survival was longer in the GJ group than in the PG group. Post-operative complication rate was lower in GJ group than in PG group. Conclusions: GJ is well tolerated and offers improved survival compared with PG and SP in the patients with AGCPS. High CIR improved MST. Success of chemotherapy introduction might improve survival. Enabling oral intake is important for chemotherapy. However, it is very difficult to select a treatment method that suits the patient individually. GPS might be an important predictor in the selection of the treatment method for unresectable AGCPS.

Antibiotic susceptibility survey of blood-borne MRSA isolates in Japan from 2008 through 2011

We conducted an antibiotic susceptibility survey of 830 blood-borne methicillin resistant Staphylococcus aureus collected from nationwide hospitals in Japan over a three-year period from January 2008 through May 2011. Antibiotic susceptibility was judged according to the criteria recommended by the Clinical Laboratory Standard Institute. Over 99% of the MRSA showed to be susceptible to teicoplanin, linezolid, sulfamethoxazole/trimethoprim and vancomycin, and over 97% of them were susceptible to daptomycin, arbekacin and rifampin. The majority of the MRSA strains showed resistant to minocycline, meropenem, imipenem, clindamycin, ciprofloxacin, cefoxitin, and oxacillin in the rates of 56.6, 72.9, 73.7, 78.7, 89.0, 99.5, and 99.9%, respectively. Among the MRSA strains, 72 showed reduced susceptibility to vancomycin, including 8 strains (0.96%) of vancomycin-intermediate S. aureus (VISA), 54 (6.51%) of heterogeneous vancomycin-intermediate S. aureus (hVISA), and 55 (5.63%) of β-lactam antibiotics-induced vancomycin resistant S. aureus (BIVR). Unexpectedly, among the 54 hVISA and 55 BIVR, 45 isolates (83.3% and 81.8%, respectively) showed both hVISA and BIVR phenotypes. A new trend of vancomycin resistance found in this study was that VISA strains were still prevalent among the bacteremic specimens. The high rates of the hVISA/BIVR two-phenotypic vancomycin resistance, and the prevalence of VISA in the bloodborne MRSA call attention in the MRSA epidemiology in Japan.

TG13 guidelines for diagnosis and severity grading of acute cholangitis (with videos)

Since the publication of the Tokyo Guidelines for the management of acute cholangitis and cholecystitis (TG07), diagnostic criteria and severity assessment criteria for acute cholangitis have been presented and extensively used as the primary standard all over the world. However, it has been found that there are crucial limitations in these criteria. The diagnostic criteria of TG07 do not have enough sensitivity and specificity, and its severity assessment criteria are unsuitable for clinical use. A working team for the revision of TG07 was organized in June, 2010, and these criteria have been updated through clinical implementation and its assessment by means of multi-center analysis. The diagnostic criteria of acute cholangitis have been revised as criteria to establish the diagnosis where cholestasis and inflammation demonstrated by clinical signs or blood test in addition to biliary manifestations demonstrated by imaging are present. The diagnostic criteria of the updated Tokyo Guidelines (TG13) have high sensitivity (87.6 %) and high specificity (77.7 %). TG13 has better diagnostic capacity than TG07. Severity assessment is classified as follows: Grade III: associated with organ failure; Grade II: early biliary drainage should be conducted; Grade1: others. As for the severity assessment criteria of TG07, separating Grade II and Grade I at the time of diagnosis was impossible, so they were unsuitable for clinical practice. Therefore, the severity assessment criteria of TG13 have been revised so as not to lose the timing of biliary drainage or treatment for etiology. Based on evidence, five predictive factors for poor prognosis in acute cholangitis--hyperbilirubinemia, high fever, leukocytosis, elderly patient and hypoalbuminemia--have been extracted. Grade II can be diagnosed if two of these five factors are present. Free full-text articles and a mobile application of TG13 are available via http://www.jshbps.jp/en/guideline/tg13.html.

TG13 indications and techniques for gallbladder drainage in acute cholecystitis (with videos)

Percutaneous transhepatic gallbladder drainage (PTGBD) is considered a safe alternative to early cholecystectomy, especially in surgically high-risk patients with acute cholecystitis. Although randomized prospective controlled trials are lacking, data from most retrospective studies demonstrate that PTGBD is the most common gallbladder drainage method. There are several alternatives to PTGBD. Percutaneous transhepatic gallbladder aspiration is a simple alternative drainage method with fewer complications; however, its clinical usefulness has been shown only by case-series studies. Endoscopic naso-gallbladder drainage and gallbladder stenting via a transpapillary endoscopic approach are also alternative methods in acute cholecystitis, but both of them have technical difficulties resulting in lower success rates than that of PTGBD. Recently, endoscopic ultrasonography-guided transmural gallbladder drainage has been reported as a special technique for gallbladder drainage. However, it is not yet an established technique. Therefore, it should be performed in high-volume institutes by skilled endoscopists. Further prospective evaluations of the feasibility, safety, and efficacy of these various approaches are needed. This article describes indications and techniques of drainage for acute cholecystitis.Free full-text articles and a mobile application of TG13 are available via http://www.jshbps.jp/en/guideline/tg13.html.

TG13 guidelines for diagnosis and severity grading of acute cholangitis (with videos)

Since the publication of the Tokyo Guidelines for the management of acute cholangitis and cholecystitis (TG07), diagnostic criteria and severity assessment criteria for acute cholangitis have been presented and extensively used as the primary standard all over the world. However, it has been found that there are crucial limitations in these criteria. The diagnostic criteria of TG07 do not have enough sensitivity and specificity, and its severity assessment criteria are unsuitable for clinical use. A working team for the revision of TG07 was organized in June, 2010, and these criteria have been updated through clinical implementation and its assessment by means of multi-center analysis. The diagnostic criteria of acute cholangitis have been revised as criteria to establish the diagnosis where cholestasis and inflammation demonstrated by clinical signs or blood test in addition to biliary manifestations demonstrated by imaging are present. The diagnostic criteria of the updated Tokyo Guidelines (TG13) have high sensitivity (87.6 %) and high specificity (77.7 %). TG13 has better diagnostic capacity than TG07. Severity assessment is classified as follows: Grade III: associated with organ failure; Grade II: early biliary drainage should be conducted; Grade1: others. As for the severity assessment criteria of TG07, separating Grade II and Grade I at the time of diagnosis was impossible, so they were unsuitable for clinical practice. Therefore, the severity assessment criteria of TG13 have been revised so as not to lose the timing of biliary drainage or treatment for etiology. Based on evidence, five predictive factors for poor prognosis in acute cholangitis--hyperbilirubinemia, high fever, leukocytosis, elderly patient and hypoalbuminemia--have been extracted. Grade II can be diagnosed if two of these five factors are present. Free full-text articles and a mobile application of TG13 are available via http://www.jshbps.jp/en/guideline/tg13.html.

New diagnostic criteria and severity assessment of acute cholecystitis in revised Tokyo Guidelines

Background

The Tokyo Guidelines for the management of acute cholangitis and cholecystitis (TG07) were published in 2007 as the world’s first guidelines for acute cholangitis and cholecystitis. The diagnostic criteria and severity assessment of acute cholecystitis have since been widely used all over the world. A validation study of TG07 has shown that the diagnostic criteria for acute cholecystitis are highly reliable but that the definition of definite diagnosis is ambiguous. In addition, considerable new evidence referring to acute cholecystitis as well as evaluations of TG07 have been published. Consequently, we organized the Tokyo Guidelines Revision Committee to evaluate TG07, recognize new evidence, and conduct a multi-center analysis to revise the guidelines (TG13).

Methods and materials

We retrospectively analyzed 451 patients with acute cholecystitis from multiple tertiary care centers in Japan. All 451 patients were first evaluated using the criteria in TG07. The “gold standard” for acute cholecystitis in this study was a diagnosis by pathology. The validity of TG07 diagnostic criteria was investigated by comparing clinical with pathological diagnosis.

Results

Of 451 patients evaluated, a total of 227 patients were given a diagnosis of acute cholecystitis by pathological examination (prevalence 50.3 %). TG07 criteria provided a definite diagnosis of acute cholecystitis in 224 patients. The sensitivity of TG07 diagnostic criteria for acute cholecystitis was 92.1 %, and the specificity was 93.3 %. Based on the preliminary results, new diagnostic criteria for acute cholecystitis were proposed. Using the new criteria, the sensitivity of definite diagnosis was 91.2 %, and the specificity was 96.9 %. The accuracy rate was improved from 92.7 to 94.0 %. In regard to severity grading among 227 patients, 111 patients were classified as Mild (Grade I), 104 as Moderate (Grade II), and 12 as Severe (Grade III).

Conclusion

The proposed new diagnostic criteria achieved better performance than the diagnostic criteria in TG07. Therefore, the proposed criteria have been adopted as new diagnostic criteria for acute cholecystitis and are referred to as the 2013 Tokyo Guidelines (TG13). Regarding severity assessment, no new evidence was found to suggest that the criteria in TG07 needed major adjustment. As a result, TG07 severity assessment criteria have been adopted in TG13 with minor changes.

Nationwide surveillance of antimicrobial susceptibility patterns of pathogens isolated from surgical site infections (SSI) in Japan

To investigate the trends of antimicrobial resistance in pathogens isolated from surgical site infections (SSI), a Japanese surveillance committee conducted the first nationwide survey. Seven main organisms were collected from SSI at 27 medical centers in 2010 and were shipped to a central laboratory for antimicrobial susceptibility testing. A total of 702 isolates from 586 patients with SSI were included. Staphylococcus aureus (20.4 %) and Enterococcus faecalis (19.5 %) were the most common isolates, followed by Pseudomonas aeruginosa (15.4 %) and Bacteroides fragilis group (15.4 %). Methicillin-resistant S. aureus among S. aureus was 72.0 %. Vancomycin MIC 2 μg/ml strains accounted for 9.7 %. In Escherichia coli, 11 of 95 strains produced extended-spectrum β-lactamase (Klebsiella pneumoniae, 0/53 strains). Of E. coli strains, 8.4 % were resistant to ceftazidime (CAZ) and 26.3 % to ciprofloxacin (CPFX). No P. aeruginosa strains produced metallo-β-lactamase. In P. aeruginosa, the resistance rates were 7.4 % to tazobactam/piperacillin (TAZ/PIPC), 10.2 % to imipenem (IPM), 2.8 % to meropenem, cefepime, and CPFX, and 0 % to gentamicin. In the B. fragilis group, the rates were 28.6 % to clindamycin, 5.7 % to cefmetazole, 2.9 % to TAZ/PIPC and IPM, and 0 % to metronidazole (Bacteroides thetaiotaomicron; 59.1, 36.4, 0, 0, 0 %). MIC₉₀ of P. aeruginosa isolated 15 days or later after surgery rose in TAZ/PIPC, CAZ, IPM, and CPFX. In patients with American Society of Anesthesiologists (ASA) score ≥3, the resistance rates of P. aeruginosa to TAZ/PIPC and CAZ were higher than in patients with ASA ≤2. The data obtained in this study revealed the trend of the spread of resistance among common species that cause SSI. Timing of isolation from surgery and the patient's physical status affected the selection of resistant organisms.

Efficacy and safety of intravenous daptomycin in Japanese patients with skin and soft tissue infections

Daptomycin is a lipopeptide antibiotic active against gram-positive organisms and recently approved for marketing in Japan. This study investigates the efficacy and safety of daptomycin in Japanese patients with skin and soft tissue infections (SSTIs) caused by methicillin-resistant Staphylococcus aureus (MRSA) for regulatory filing in Japan. Overall, 111 Japanese patients with SSTI were randomized in this open-label, randomized, active-comparator controlled, parallel-group, multicenter, phase III study. Patients received intravenous daptomycin 4 mg/kg once daily or vancomycin 1 g twice daily for 7–14 days. Efficacy was determined by a blinded Efficacy Adjudication Committee. Among patients with SSTIs caused by MRSA, 81.8 % (95 % CI, 69.1–90.9) of daptomycin recipients and 84.2 % (95 % CI, 60.4–96.6) of vancomycin recipients achieved a successful clinical response at the test-of-cure (TOC) visit. The microbiological success rate against MRSA at the TOC visit was 56.4 % (95 % CI, 42.3–69.7) with daptomycin and 47.4 % (95 % CI, 24.4–71.1) with vancomycin. Daptomycin was generally well tolerated; most adverse events were of mild to moderate severity. The measurement of daptomycin concentration in plasma revealed that patients with mild or moderate impaired renal function showed similar pharmacokinetics profiles to patients with normal renal function. Clinical and microbiological responses, stratified by baseline MRSA susceptibility, suggested that patients infected with MRSA of higher daptomycin MIC showed a trend of lower clinical success with a P value of 0.052 by Cochran–Armitage test. Daptomycin was clinically and microbiologically effective for the treatment of MRSA-associated SSTIs in Japanese patients.

100 μA-100 kV Photon-counting X-ray Computed Tomography System Using an LSO-MPPC Detector and a High-Speed Comparator and its Application to Gadolinium Imaging

A high-sensitive x-ray computed tomography (CT) system is useful for decreasing absorbed dose for patients, and we performed preliminary experiments for first-generation photon-counting CT using a high-sensitive single detector. X-ray photons are detected using an LSO [Lu₂(SiO₄)O] single crystal scintillator and a multipixel photon counter (MPPC). The photocurrent from the MPPC is amplified by a current-voltage amplifier and an integrator, and the event pulse is sent to a high-speed comparator. Logical pulses are then produced by the comparator and are counted by a counter card. Tomography is accomplished by repeated linear scans and rotations of an object, and projection curves of the object are obtained by the linear scan. The count rate decreased with increase in lower level voltage of the comparator V_l, and the maximum count rate was 265 kcps at a V_l of 0.4 V. The exposure time for obtaining a tomogram was 10 minutes at a scan step of 0.5 mm and a rotation step of 1.0°. The image contrast of gadolinium medium slightly varied with change in V_l. We carried out low-dose-rate photon-counting CT at a tube current of 100 μA and a tube voltage of 100 kV. The energy-dispersive effect of the CT image was confirmed by selecting V_l. The absorbed dose for objects can be reduced using the linear detector consisting of plural LSO-MPPC detectors.

Successful treatment of a common hepatic artery pseudoaneurysm using a coronary covered stent following pancreatoduodenectomy: report of a case

This report presents the case of a common hepatic artery (CHA) pseudoaneurysm secondary to postoperative pancreatic fistula (POPF) after pancreatoduodenectomy (PD), which was successfully treated using a coronary covered stent. A 70-year-old female underwent subtotal stomach-preserving PD for middle cholangiocarcinoma. POPF was identified on postoperative day (POD) 7, and the patient suddenly lost 500 ml of blood via the abdominal drain on POD 19. Urgent celiac arteriography revealed a CHA pseudoaneurysm. A coronary covered stent was placed to prevent rupture of the pseudoaneurysm and to maintain hepatic arterial flow, instead of performing transarterial embolization. No vascular adverse events were encountered during or after the procedure. Computed tomography and angiography showed a patent stent graft and good hepatic arterial flow 9 months after placement of the stent. Endovascular stent-graft placement not only treated the pseudoaneurysm, but also preserved the arterial blood flow. This report describes the placement of a covered stent graft for delayed hemorrhage after PD.

Demonstration of enhanced iodine K-edge imaging using an energy-dispersive X-ray computed tomography system with a 25 mm/s-scan linear cadmium telluride detector and a single comparator

An energy-dispersive (ED) X-ray computed tomography (CT) system is useful for carrying out monochromatic imaging. To perform enhanced iodine K-edge CT, we developed an oscillation linear cadmium telluride (CdTe) detector with a scan velocity of 25 mm/s and an energy resolution of 1.2 keV. CT is performed by repeated linear scans and rotations of an object. Penetrating X-ray photons from the object are detected by the CdTe detector, and event signals of X-ray photons are produced using charge-sensitive and shaping amplifiers. The lower photon energy is determined by a comparator device, and the maximum photon energy of 60 keV corresponds to the tube voltage. Rectangular-shaped comparator outputs are counted by a counter card. In the ED-CT, tube voltage and current were 60 kV and 0.30 mA, respectively, and X-ray intensity was 14.8 μGy/s at 1.0m from the source at a tube voltage of 60 kV. Demonstration of enhanced iodine K-edge X-ray CT for cancer diagnosis was carried out by selecting photons with energies ranging from 34 to 60 keV.