Correlation Analysis between Antibiotic Resistance Gene Profile and Susceptibility to Gentamicin, Clindamycin, and Minocycline in Clinically Isolated Methicillin-resistant Staphylococcus aureus

This study aimed to elucidate retrospectively the correlations between the genome and phenotype in clinical methicillin-resistant Staphylococcus aureus (MRSA) gentamicin (GEN), clindamycin (CLI), and minocycline (MIN) susceptibility using next-generation sequencing (NGS) technology. Ninety two MRSA strains were isolated from individual inpatients treated in Hiroshima University Hospital, Hiroshima, Japan, extracted for their genomic DNA, and sequenced using an Illumina® MiSeq sequencer to obtain their de novo whole-genome assembly. An in silico analysis using ResFinder was performed to obtain the genomic antimicrobial susceptibility profile which was analyzed together with GEN, CLI, and MIN minimum inhibitory concentration (MIC) levels. This study found aac(6’)aph(2”)+, spc+, ermA+, tetM+ MRSA strains were predominant (42/92) and were shown to exhibit >16 mg/L GEN (40/42), >4 mg/L CLI (26/42), and >8 mg/L MIN MIC levels (30/42). Associations between aac(6’)aph(2”) detections and GEN MIC levels (p <0.001), ermA detections and CLI MIC levels (p <0.001), and tetM detections and MIN MIC levels (p <0.001) were revealed in this study. Correlations between simultaneous detections of aac(6’) aph(2”)-spc-ermA-tetM and GEN MIC levels (φc= 0.398, p <0.001), CLI MIC levels (φc= 0.448, p <0.001), and MIN MIC levels (φc= 0.515, p <0.001) were revealed in this study. The genomicphenotypic correlation analyses in this study provided an insight of a rapid antimicrobial detection in MRSA using in silico genomic antimicrobial susceptibility profiling.This research was partially supported by a Grant-in-Aid for Scientific Research (A) (No.15H02567) from the Ministry of Education, Culture, Sports, Science, and Technology and those from Ministry of Health, Labor, and Welfare of the Government of Japan

Effects of Different Types of Dietary Fibers on Fermentation by Intestinal Flora

Purpose: A treatment for chronic constipation is dietary fiber intake. This study aimed to determine the effects of different types of dietary fibers on the microbiota in the large intestine. Methods: Nine healthy volunteers participated in this study. Breath hydrogen test was used to determine the dietary fiber fermentations. The presence of hydrogen in the breath indicates intestinal bacterial activities. Participants fasted overnight and ate white bread (200 g) with 10 g of each type of dietary fiber: (1) cellulose, (2) soy fiber, (3) guar gum, and (4) control (without any dietary fiber). Samples were collected before and every 1 hour after eating, for 8 h. Another test compared the effects between cellulose and guar gum with a loaded food, which activates intestinal fermentation, and samples were collected using the same methods. Results: During 8 h of measurements, breath hydrogen concentration in the soy fiber group were higher than that of the control, but were not significantly different. Changes in the guar gum group were similar to those in the control. However, breath hydrogen concentrations in the cellulose group did not increase even after eating white bread that caused large intestinal fermentation 2.9 ± 0.7 ppm, which was significantly lower than that of the guar gum group (7.4 ± 1.7 ppm, p < 0.01). In the study with a well-fermented food intake, cellulose reduced breath hydrogen concentrations, but its difference with that of the guar gum group was statistically non-significant. Conclusion: Cellulose might have a suppressive effect on large intestinal fermentation. Therefore, this compound may be beneficial in treating chronic constipation

Accuracy management survey of nucleic acid amplification tests using inactivated SARS-CoV-2 in Hiroshima Prefecture

At the beginning of 2020, the number of laboratories performing SARS-CoV-2 testing increased with the rapid expansion of COVID-19 in Hiroshima Prefecture. Thus, it is necessary to compare and verify the validity of the test results among local laboratories. In this study, we distributed the same standard samples to laboratories that performed COVID-19 testing using the nucleic acid amplification method and confirmed the accuracy of the tests. The SARS-CoV-2 strain distributed by the National Institute of Infectious Diseases (NIID), Japan, was used for testing. As measured by RT-qPCR, a specific amount of the virus was inactivated by ethanol and dried as specimens for distribution. This study included 27 tests performed at 15 laboratories conducting or planning to conduct nucleic acid amplification tests (RT-qPCR and LAMP methods) for SARSCoV-2. The detection limit of each test method was set at the value provided by the NIID. The accuracy of the tests was examined to determine whether they met the required accuracy criteria. SARS-CoV-2 genomic RNA was reliably detected in all 27 tests. The inactivated specimens used in this study were safe to distribute and could be used as positive controls for all methods.This study was supported by a grant from the Government-Academia Collaboration of Hiroshima Prefecture and by a research grant for COVID-19 from AMED, Japan under Grant Number 20he0622011h0001(to J. T.)

Use of the Hydrogen Breath Test to Determine the Influence of Antibiotic Prophylaxis on Intestinal Flora

Purpose: This experimental study was designed to use the hydrogen (H2) breath test to investigate changes in the intestinal flora of patients that were administered prophylactic antibiotics for 48 hours after surgery. Methods: Altogether, 22 patients were divided into two groups and the antimicrobial prophylactics, cefazolin (3.0 g/day) or sulbactam/ampicillin (4.5 g/day), were administered on induction of anaesthesia for 48 hours after surgery. End expiratory breath samples were collected on the morning of the day of surgery and every morning for 1-6 days after surgery. Results: H2 breath concentration significantly decreased in each group on day 1 (cefazolin: 1.20 ± 0.39 ppm vs. sulbactam/ampicillin: 1.17 ± 0.34 ppm). On day 2, the H2 concentration in the sulbactam/ampicillin group was significantly lower than the cefazolin group (cefazolin: 6.4 ± 2.2 ppm vs. sulbactam/ampicillin: 1.0 ± 0.4 ppm, p < 0.05). H2 concentration was still lower in the sulbactam/ampicillin group (1.3 ± 0.3 ppm vs. 3.3 ± 1.0 ppm, p = 0.10) on day 3. On days 4-6, H2 concentration was essentially the same for both groups. Discussion: Colonic anaerobes are thought to be a reservoir of resistant organisms and prolonged antimicrobial treatment is a major cause for the development of resistance. Surgical prophylaxis is basically recommended for use within 24 hours after surgery. The breath H2 concentration in both groups significantly decreased 24 hours after administration. These results suggest that both antibiotics influence the activity of colonic anaerobes and the duration of surgical antibiotic prophylaxis should be as short as possible

Pouchitis disease activity index (PDAI) does not predict patients with symptoms of pouchitis who will respond to antibiotics

To evaluate whether the pouchitis disease activity index (PDAI) alone is sufficient to select appropriate treatment plans for ulcerative colitis patients with bowel movement problems following ileal pouch-anal anastomosis (IPAA). The study included 70 patients undergoing an IPAA. For these patients, an evaluation by PDAI was performed prospectively at 1-2 years after the ileostomy closure. When the symptoms relevant to bowel movement appeared, PDAI was evaluated and metronidazole or ciprofloxacin was administered. Pouchitis was diagnosed in patients with PDAI scores of 7 or higher. The patients whose PDAI score was less than 7 and who responded to antibiotic therapy were defined as treatment responders having disease not diagnosed by PDAI (TR-NDPDAI). Pouchitis was diagnosed in 16 of the 70 enrolled patients (22.9%) using the PDAI scoring system. Of these 16 patients, 11 had acute pouchitis and 5 had chronic pouchitis. Twenty-one patients whose PDAI score was less than 7 were symptomatic. Among them, 12 were TR-NDPDAI. In patients with TR-NDPDAI, antibiotic treatment resulted in significant improvements in the PDAI score (P < 0.001) and in clinical symptoms (P < 0.001) after treatment. Antibiotic treatment was effective in a considerable number of ulcerative colitis patients whose PDAI score was less than 7 after IPAA

Viable SARS-CoV-2 detected in the air of hospital rooms of patients with COVID-19 with an early infection

Objectives: This study assessed the concentration of SARS-CoV-2 in the air of hospital rooms occupied by patients with COVID-19 who had viable SARS-CoV-2 in nasopharyngeal (NP) samples in early infection. Methods: Between July and October 2021, NP swabs were collected from 20 patients with early SARS-CoV-2 infection admitted to a tertiary hospital in Japan. Air samples were collected from their rooms, tested for SARS-CoV-2 RNA, and cultured to determine potential infectivity. Results: The NP swab samples of 18 patients were positive for viable SARS-CoV-2 (median concentration: 4.0 × 105 tissue culture infectious dose 50/ml). In the air samples, viral RNA (median concentration: 1.1 × 105 copies/m3) was detected in 12/18 (67%) patients, and viable virus (median concentration: 8.9 × 102 tissue culture infectious dose 50/m3) was detected in 5/18 (28%) patients. The median time between illness onset and sampling was 3 days. The RNA concentration was significantly higher in samples wherein viable SARS-CoV-2 was detected than in samples in which viable virus was not detected (P-value = 0.027). Conclusion: Viable SARS-CoV-2 can be detected in the air surrounding patients with early SARS-CoV-2 infection. Health care workers should pay attention to infection control when caring for patients with early SARS-CoV-2 infection

High Vaccination Coverage among Children during Influenza A(H1N1)pdm09 as a Potential Factor of Herd Immunity

The objective of this study was to identify factors related to the expansion of infection and prevention of influenza A(H1N1)pdm09. A retrospective non-randomized cohort study (from June 2009 to May 2010) on influenza A(H1N1)pdm09 was conducted in a sample of residents from Hiroshima Prefecture, Japan. The cumulative incidence of the influenza A(H1N1)pdm09 and the pandemic vaccine effectiveness (VE) were estimated. The response rate was 53.5% (178,669/333,892). Overall, the odds ratio of non-vaccinated group to vaccinated group for cumulative incidence of influenza A(H1N1)pdm09 was 2.18 (95% confidence interval (CI): 2.13–2.23) and the VE was 43.9% (CI: 42.8–44.9). The expansion of infection, indicating the power of transmission from infected person to susceptible person, was high in the 7–15 years age groups in each area. In conclusion, results from this survey suggested that schoolchildren-based vaccination rate participates in determining the level of herd immunity to influenza and children might be the drivers of influenza transmission. For future pandemic preparedness, vaccination of schoolchildren may help to prevent disease transmission during influenza outbreak

Specific antibiotic prophylaxis based on bile cultures is required to prevent postoperative infectious complications in pancreatoduodenectomy patients who have undergone preoperative biliary drainage

Background Preoperative biliary drainage (PBD) is associated with bacterial contamination of bile, but the effects of PBD on morbidity after pancreatoduodenectomy remain controversial. The aim of this study was to characterize bile contamination to develop successful specific antibiotic prophylactic strategies for pancreatoduodenectomy. Methods Ninety-one consecutive patients who underwent pancreatoduodenectomy for periampullary tumor were prospectively evaluated. Prophylactic antibiotics were selected based on preoperative bile cultures. Bile cultures and postoperative complications were compared in 46 patients who underwent PBD (drainage group) versus 45 patients who did not (nondrainage group). Results The incidence of positive bile cultures was higher in the drainage group (78%) than in the nondrainage group (36%) (P < 0.001). In the drainage group, positive bile cultures were frequently polymicrobial (61%) and demonstrated resistance to several antibiotics, including cefazolin (83%), cefmetazole (72%), and cefpirome (64%). Overall morbidity (30-0x1.fd580000008p+0nd 22%) and infectious morbidity (13 0x1.f72676b636142p+855nd 11%) did not differ significantly between the drainage and nondrainage groups, respectively. Conclusions PBD had a notable influence on bile microbial contamination, including a higher rate of antibiotic resistance. Therefore, specific antibiotic prophylaxis based on bile culture is required for preventing infectious complications in pancreatoduodenectomy patients who undergo PBD

Prognostic impact of perineural invasion following pancreatoduodenectomy with lymphadenectomy for ampullary carcinoma

Purpose: The aim of this study was to identify prognostic factors in patients undergoing pancreatoduodenectomy with lymphadenectomy for ampullary carcinoma. Methods: The records of 46 consecutive patients with ampullary carcinoma who underwent pancreatoduodenectomy from 1988 through 2006 were retrospectively reviewed. Results: A 98% rate of potentially curative (R0) resection was achieved. There was no 30-day mortality. Overall 5-year survival rate was 64%.0 Univariate analysis revealed that T3 and T4 tumor (ie, pancreatic parenchymal invasion) (P<0.001), lymph node metastasis (P=0.01), and perineural invasion (P<0.001) were significant predictors of poor prognosis. Furthermore, perineural invasion was found to be a significant independent predictor of poor prognosis by multivariate analysis (P=0.024). Conclusions: Pancreatoduodenectomy with lymphadenectomy for ampullary carcinoma is a safe surgical procedure with an acceptable cure rate. The presence of perineural invasion may be useful for predicting poor prognosis in patients with ampullary carcinoma who undergo potentially curative resection

Prediction for the Development of Postoperative Infections in the Operation of Esophageal Cancer Compared with Gastric Surgery

The purpose of this study was to assess the point at which the postoperative infection has occurred in order to decide upon the proper duration of prophylactic antibiotic use. Another goal of this study was to determine whether prediction for the development of postoperative infections in major surgery such as esophagectomy should be the same as that in routine gastroenterological surgery. Twenty-five patients who underwent transthoracic esophagectomy and 127 patients who underwent gastrectomy were studied.　　 On the third day after gastric surgery, the body temperature of patients who developed an infection was higher than that of the patients who did not develop an infection. The relative changes in peripheral white blood count (WBC), and C-reactive protein (CRP) concentration on the third and fourth days were more predictive of the development of infection than the absolute values. Almost all patients with systemic inflammatory response syndrome (SIRS) on the third day after gastric surgery developed an infection. On the other hand, the incidence of SIRS in patients who did not develop an infection was high on both the third and fourth days after esophageal surgery. It was nearly impossible to predict who would develop an infection in esophageal surgery. The high incidence of postoperative infections, and their significant consequences justify planned successive postoperative antibiotic use in esophageal surgery