Abstract
The 37th meeting of the Japanese Society of Surgical Infection was held in Tokyo on November 8 and 9, 2024. The meeting was very well organized and run, with, by my estimate, more than 500 attendees. The sheer number of presentations was impressive, resulting in 5 day-long parallel sessions along with ongoing poster exhibits. The quality of data, analysis, and presentation was first-rate. Sessions all had specific themes, many of which were similar to those seen outside of Western meetings, such as surgical site infection (SSI) prevention, antimicrobial resistance, and critical care. Novel topics for symposia were also presented, including many subspecialties (transplantation, neurosurgery, cardiac surgery, and orthopedics) and those related to larger systems’ issues (medical safety, infection control, medical ethics, and multidisciplinary cooperation). One very unusual session was devoted to the International Space Station and Space Medicine. Overall, the meeting was highly educational and led to an appreciation of how surgical infections are similarly and dissimilarly approached between Japan and the United States.
Highlights from six of the excellent sessions are below:
Dr. Keita Morikane (my host and incoming president of the Japanese Society of Surgical Infection) and Dr. Fujita moderated a session on surveillance data from Japan in many areas of concern to US surgeons. Of course, comparing their results to those from the United States was very interesting. I found the following points remarkable:
Data from the 2010 to 2014 era comparing SSI rates between Japan, the United States, Holland, Germany, and the United Kingdom all implied the United States has the lowest SSI rates by far. However, data for the United States was not consistent with my personal observations; for example, an SSI rate after colorectal surgery of 2.1%–2.4%, calls into question its accuracy. Data related to pathogens causing SSI in Japan in some instances were noticeably different from what I would expect in the United States. The most common pathogen isolated from SSI after appendectomy in Japan is Pseudomonas aeruginosa, which is not routinely covered by standard prophylaxis in many hospitals in the United States. The most common pathogen causing SSI after hepatobiliary, gastric, and colorectal procedures is Enterococcus faecalis, followed by P. aeruginosa for gastric and colorectal procedures. This finding, if reproduced in the United States, would suggest a different prophylaxis strategy for US surgeons. Although pathogens may differ, an outstanding multivariable analysis of risk factors for SSI in Japan detected many of the same factors we see in the United States, including age, wound class, duration of surgery, American Society of Anesthesiologists (ASA) score, and emergency procedures. A consistent increased risk among men, however, was somewhat surprising and has only inconsistently been observed in the United States. One excellent observation among Japanese patients was a substantial decrease in the rate of ventilator-associated pneumonia (VAP). Between 2009 and 2010, VAP rates were 4–6 events/1000 ventilator days. Those numbers have declined steadily to around 2 in 2022 and 2023.
An excellent session moderated by Drs. Maruyama and Mizuuchi addressed the difficult problem of postoperative infections related to colorectal surgery.
A very thoughtful discussion about the history of preoperative oral antibiotic bowel preparation (OABP) was given. The major findings of the ORALEV study of oral antibiotics prior to colorectal surgery (Lancet Gastroenterol Hepatol 2020) were given, showing a 6% reduction in SSI rates. One recent network meta-analysis (BJS Open 2023) and one recent meta-analysis (J Glob Antimicrob Resist 2023) were also presented, confirming the benefit of OABP. An additional talk discussed the uptake of OABP in the USA versus Japan. After the original landmark publication by Nichols in 1997, oral antibiotics were adopted by over 80% of American surgeons and 70% of Japanese surgeons. However, usage declined significantly by 2010. However, more recent information implies a re-adoption of the practice in the USA to >80%, though data from 2014 suggested fewer than 10% of Japanese surgeons were using OABP. However, results from a recent survey of 456 Japanese surgeons noted primarily kanamycin and metronidazole.
Drs. Mayumi and Oge led a session focusing on novel methods to prevent SSI. Several interventions that are not commonly used in the United States were described and supported. These were presented as Core Questions used for the formulation of Japanese SSI prevention guidelines.
A meta-analysis of studies of probiotics and synbiotics demonstrated striking effects related to the prevention of SSI. Probiotics were associated with an RR of 0.69 and synbiotics with a risk of 0.63, both highly significant. Nonetheless, this is an unused strategy in the United States. The impact of good oral hygiene was discussed, an area that in the United States is not frequently considered outside of the ICU. Data from a Japanese propensity-score matched multivariable analysis (Surgery 2022) demonstrated that lack of perioperative oral care was associated with both incisional and organ/space SSI with a remarkable odds ratio of around 2. Brilliantly, they related these findings to the Alverdy Trojan Horse hypothesis that pathogens can travel from the mouth to the wound inside leukocytes, ultimately causing an SSI. The ongoing controversy regarding skin preparation before operation was discussed. Data from both the PREP-IT study (Lancet 2022) and the PICASSo study (JAMA 2024) were presented, each demonstrating similar outcomes in terms of SSI between the chlorhexidine-based and iodine-based comparators. Conclusion: Choice of skin preparation agent should depend on local factors.
An update symposium was moderated by Drs. Oge and Obara, highlighting recent surgical infectious diseases publications of interest. These important papers included
From the Annals of Surgery in 2024, a large Japanese observational esophagectomy study showing a relationship between receiving ampicillin/sulbactam prophylaxis (vs. cefazolin) and reductions in rates of SSI, anastomotic leak, and respiratory failure. Naturally, a randomized, controlled trial to confirm these findings would be ideal. From JAMA in 2023, the National Surgical Quality Improvement Program (NSQIP)-based study of piperacillin/tazobactam versus cefoxitin for the prevention of SSI following pancreaticoduodenectomy. This trial showed a lower rate in patients receiving piperacillin/tazobactam, driven primarily by patients with a preoperatively placed stent. From JAMA Surgery in 2024, a well-conducted Korean RCT comparing a plastic wound protector to surgical gauze on subcutaneous tissue to prevent SSI after open abdominal procedures. The wound protector was associated with an overall reduction in SSI rates, from 21% to 11%. From Annals of Surgery in 2023, a well-conducted Japanese RCT of 941 gastroenterological surgery patients compared incisional irrigation with saline versus povidone-iodine. No difference in SSI rates was noted, in contrast to some recent meta-analyses and guidelines. From JAMA in 2024, the BLING III trial of continuous infusion β-lactam antimicrobials in sepsis was reviewed. Although a decrease in all-cause mortality was not seen (numerically but not statistically lower), an accompanying meta-analysis implied improved outcomes with continuous infusion.
A symposium focusing on the challenges of resistant bacteria in surgical infections was moderated by Drs. Oge and Mizuguchi. Not surprisingly, concerns in Japan mirror those in the United States, with perhaps slightly more concern about extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales.
A fascinating review of patients with appendicitis and their associated microbiology was presented. Data from 673 patients, including cultures from 570, were reviewed. Cefmetazole followed by flomoxef were the most frequently used antibiotics. 114 (20%) had antimicrobial-resistant organisms cultured, including 9 with ESBL-producing E. coli. Unfortunately, no risk factor associated with resistant pathogens could be determined, and, similar to the United States, the need to change standard treatment regimens still remains unclear.
In the afternoon of the second day of the meeting, an “Asian Symposium” was held, moderated by Dr. Yoshida and Dr. Lee (from Korea). Three talks were given and gave an interesting picture of surgical efforts throughout the region.
Dr. Nakagawa from the Departments of Emergency and General Internal Medicine spoke about recent changes in the Japanese Health Care Systems intended to improve work conditions and job satisfaction. She spoke admirably, using her own professional training and work history to illustrate the difficult conditions Japanese physicians have faced in the past related to the volume and intensity of work. Survey data was presented that two areas that could be improved in physicians’ lives were “Activities outside of medicine” and “Rest,” as well as showing that the most time for residents was spent on documentation. Finally, novel solutions related to increasing the responsibilities and scope of practice of nurses, similar to our Advanced Practice Providers, were proposed. Dr. Park from Korea discussed Korean Surgical Infection Society guidelines related to SSI prevention. These guidelines are structured around 12 Core Questions, many of which are similar to those found in US guidelines. Two areas that I especially appreciated, however, included an emphasis on intensive prehabilitation, including nutrition support and specific recommendations related to early drain removal and non-application of antibiotics solely because of the presence of a drain. She also addressed the difficulty of conducting accurate surveillance for SSI, noting how trends in the use of ERAS protocols and earlier patient discharge have made these efforts more problematic. In addition, since postoperative care may be delivered away from the hospital where the operation was performed, relying on the operative surgeon alone to report SSI was not effective. Dr. Saguil from the Philippines and the founding president of the Philippines Surgical Infection Society described the nationwide efforts made in her country to address the problem of SSI. The amount of work in the past decade in this area has been admirable, and she noted a key moment was in 2015 when the Philippines’ Department of Health required inclusion of surgeons in antimicrobial stewardship efforts. The inclusion of surgeons in the formulation of local and national guidelines has led to more consistent adoption. In addition, the Philippine government is in the process of providing resources to improve hospital staffing and infrastructure, allowing more robust SSI prevention and surveillance efforts.