Genetic characterization of methicillin-resistant / susceptible Staphylococcus aureus (MRSA/MSSA) and Staphylococcus argenteus clinical isolates in Bangladesh: Dominance of ST6-MRSA-IV/t304 and detection of cfr/fexA in ST8-MSSA/t008.

Objectives: Coagulase-positive staphylococcus (CoPS), represented by Staphylococcus aureus, is a major cause of infections in humans. This study aimed to investigate molecular epidemiological characteristics, antimicrobial resistance, and their trends of CoPS in Bangladesh. Methods: Clinical isolates of CoPS were collected from two medical institutions in Bangladesh for a 2-year period and analyzed for their species, genotypes, virulence factors, antimicrobial susceptibility, and resistance determinants. Results: 172 CoPS isolates collected were identified as S. aureus or S. argenteus (170 and two, respectively). Methicillin-resistant S. aureus (MRSA) accounted for 36% (n = 61), having Staphylococcal cassette chromosome mec (SCCmec)-IV (82%) or V (18%). Panton-Valentine leukocidin (PVL) genes were detected at higher rate in methicillin-susceptible S. aureus (MSSA) (62%) than MRSA (26%). MRSA comprised 11 STs, including a dominant type ST6 (46%) associated with mostly SCCmec-IVa/spa-t304, and one isolate had genetic features of the USA300 clone (ST8/SCCmec-IVa/coa-IIIa/spa-t008/ACME-I/ΦSa2USA). STs of CC1, CC88, and CC398 were common in MSSA, with CC88 showing the highest PVL-positive rate. One MSSA isolate (ST8/spa-t008) harbored fexA and cfr showing susceptibility to linezolid. S. argenteus was methicillin-susceptible and belonged to ST2250/coa-XId. Conclusions: Genetic characteristics of current MRSA/MSSA in Bangladesh were revealed, with first identification of S. argenteus at low prevalence.

Molecular Epidemiological Characterization of Methicillin-Resistant Staphylococcus aureus from Bloodstream Infections in Northern Japan: Increasing Trend of CC1 and Identification of ST8-SCCmec IVa USA300-Like Isolate Lacking Arginine Catabolic Mobile Element.

Methicillin-resistant Staphylococcus aureus (MRSA) is a major infectious disease pathogen, and its molecular epidemiological profile has been changing. In this study, a total of 279 MRSA isolates were collected from patients with bloodstream infection (BSI) in Hokkaido, northern main island of Japan, for a 2-year period from August 2019 to July 2021. CC5 (ST5/ST764)-MRSA-IIa (SCCmec-IIa) (47%, n = 132) and CC1 (ST1/ST2725/ST2764)-MRSA-IVa (42%, n = 116) were found to be major lineages, with CC8-MRSA-IVa being lower prevalence (5%, n = 13). CC1-MRSA-IVa showed a relatively increased proportion compared with our previous study (22%, 2017-2019). Seven isolates with SCCmec IVa (2.5%) were positive for Panton-Valentine leukocidin genes on ΦSa2usa and belonged to ST8/spa-t008/agr-I/coa-IIIa, showing genetic features of the USA300 clone. Among these isolates, six isolates harbored arginine catabolic mobile element (ACME) type I typical to the USA300 clone, while it was not detected in an isolate (strain R3-8). Whole genomic analysis of strain R3-8 revealed that its chromosome was highly similar to the USA300 strain TCH1516, but lacked ACME, carrying a plasmid genetically close to that of USA300 strains. The present study revealed increasing trend of CC1-MRSA-IV and occurrence of a novel variant of the USA300 clone among MRSA from BSI in northern Japan.

Prevalence, clonal diversity, and antimicrobial resistance of hypervirulent Klebsiella pneumoniae and Klebsiella variicola clinical isolates in northern Japan.

OBJECTIVES: Hypervirulent Klebsiella pneumoniae (hvKp) and Klebsiella variicola (hvKv) cause hospital/community-acquired infections, often associated with antimicrobial resistance (AMR). This study aimed to investigate the molecular epidemiology of hvKp and hvKv in northern Japan. METHODS: A total of 500 K. pneumoniae and 421 K. variicola clinical isolates collected from August to December 2021 were studied. Prevalence of virulence factor-encoding genes, wzi sequence and associated K/KL type, sequence type (ST), and beta-lactamases and their types were characterized. RESULTS: Any virulence gene (rmpA, rmpA2, peg-344, iucA, iutA, and iroB) and/or magA was detected in 25% (n = 125) of K. pneumoniae and 1% (n = 5) of K. variicola. Among these hvKp/hvKv, 22 wzi types (18 and 4 types, respectively) and 24 STs (20 and 4 STs, respectively) were identified. Sequence types of hvKp were classified into some clonal groups (CGs), among which CG35, including six STs, was the most common (n = 59; 47%), followed by CG23, and CG65. ST268 (CG35) associated with wzi95-K20 or wzi720 was the dominant lineage (n = 43, 34%), while K1:ST23/ST249 and K2:ST65/ST86 accounted for 26% and 13% of hvKp, respectively. Extended-spectrum beta-lactamase (ESBL) genes (blaCTX-M-2, blaCTX-M-3, blaCTX-M-15, and blaCTX-M-27) were detected in only ST23 and CG35 (ST268 and ST412) hvKp. No isolate was resistant to carbapenems, without detection of the ESBL gene in K. variicola. Phylogenetically, wzi was differentiated into two main clusters of K. pneumoniae and K. variicola. A major clonal group CG347 was identified in K. variicola. CONCLUSION: Clonal structures were revealed for hvKp and hvKv clinical isolates with their AMR status in northern Japan.

Spread of multidrug resistance in non-PCV13/PCV20 serotypes of Streptococcus pneumoniae: A cross-sectional study ten years after the introduction of pneumococcal conjugate vaccine in Japan.

Ten years after the introduction of the pneumococcal conjugate vaccine (PCV) in Japan, the prevalence rates of non-PCV13 and non-PCV20 serotypes among pediatric pneumococcal isolates were 94.0% and 73.7%, respectively. The predominant non-PCV13/PCV20 serotypes (15A, 35B, and 23A) were mostly multidrug-resistant (≥80.5%), exhibiting non-susceptibility to penicillin.

Antimicrobial Resistance, Virulence Factors, and Genotypes of Enterococcus faecalis and Enterococcus faecium Clinical Isolates in Northern Japan: Identification of optrA in ST480 E. faecalis.

Enterococcus faecalis and E. faecium are the major pathogens causing community- and healthcare-associated infections, with an ability to acquire resistance to multiple antimicrobials. The present study was conducted to determine the prevalence of virulence factors, drug resistance and its genetic determinants, and clonal lineages of E. faecalis and E. faecium clinical isolates in northern Japan. A total of 480 (426 E. faecalis and 54 E. faecium) isolates collected over a four-month period were analyzed. Three virulence factors promoting bacterial colonization (asa1, efaA, and ace) were more prevalent among E. faecalis (46-59%) than E. faecium, while a similar prevalence of enterococcal surface protein gene (esp) was found in these species. Between E. faecalis and E. faecium, an evident difference was noted for resistance to erythromycin, gentamicin, and levofloxacin and its responsible resistance determinants. Oxazolidinone resistance gene optrA and phenicol exporter gene fexA were identified in an isolate of E. faecalis belonging to ST480 and revealed to be located on a cluster similar to those of isolates reported in other Asian countries. The E. faecalis isolates analyzed were differentiated into 12 STs, among which ST179 and ST16 of clonal complex (CC) 16 were the major lineage. Nearly all the E. faecium isolates were assigned into CC17, which consisted of 10 different sequence types (STs), including a dominant ST17 containing multidrug resistant isolates and ST78 with isolates harboring the hyaluronidase gene (hyl). The present study revealed the genetic profiles of E. faecalis and E. faecium clinical isolates, with the first identification of optrA in ST480 E. faecalis in Japan.

Accurate estimation of skeletal muscle mass by comparison of computed tomographic images of the third lumbar and third cervical vertebrae in Japanese patients with oral squamous cell carcinoma.

OBJECTIVES: We evaluated the accuracy of estimating the cross-sectional area (CSA) at the third lumbar vertebra (L3) based on the CSA at the third cervical vertebra (C3) using computed tomographic images, and we identified the sources of error and bias using the evaluation of absolute reliability in 89 Japanese patients with oral squamous cell carcinoma. METHODS: Skeletal muscle CSA was measured at the C3 and L3 on pretreatment computed tomographic images. We used the CSA at the C3 to estimate CSA at the L3 in an existing prediction formula. Correlation coefficients were used to evaluate the relative reliability of the estimate, and Bland-Altman analysis and minimum detectable change (MDC) were used to evaluate its absolute reliability. RESULTS: Estimated and actual CSAs at L3 were strongly correlated (r = 0.885, p < 0.001). The mean difference between the estimated and actual CSAs was - 1.0887 cm2, the 95% confidence interval was - 4.09 to 1.91 cm2 (p = 0.472), and the 95% limits of agreement were - 29.0 and 26.8 cm2. The MDC at the 95% level of confidence in estimated and actual CSAs was 27.9 cm2. CONCLUSIONS: The estimation of CSA at the L3 from the existing prediction formula with the CSA at the C3 had no systematic biases, but it did have random errors. Random errors resulted from measurement errors and biological variation. Usefulness of the existing formula is limited by physical differences in populations.

Clinical and histopathologic effects of neoadjuvant intra-arterial chemoradiotherapy with cisplatin in combination with oral S-1 on stage III and IV oral cancer.

OBJECTIVE: The aim of this study was to examine the clinical and histopathologic effects of neoadjuvant intra-arterial chemoradiotherapy (IACRT) using cisplatin in combination with oral S-1 (tegafur/gimeracil/oteracil potassium) on stage III and IV oral squamous cell carcinoma. STUDY DESIGN: Thirty patients received infusions of superselective intra-arterial cisplatin 60 mg/m2 by the Seldinger method and conventional external beam radiotherapy (total 40 Gy) combined with oral S-1 on the day of irradiation. Curative surgery and neck dissection were performed 4 to 6 weeks after IACRT. The clinical response of the primary lesion was evaluated approximately 4 weeks after IACRT. The surgically resected specimens were examined for histologic features according to the grading system for histologic evaluation and for residual tumor grade (RGrades). RESULTS: Histopathologic evaluation of the therapeutic effect was grade 2 in 10 patients and grade 3 in 16 patients. According to the distribution of RGrades, the remaining tumor cells were mostly in the central area of the primary lesion, as seen in 24 patients. CONCLUSIONS: These findings indicate that neoadjuvant IACRT with cisplatin and oral S-1 was an effective treatment, suggesting the possibility of reducing the extent of curative surgery based on RGrades.

Prevalence and Antimicrobial Resistance of Staphylococcus aureus and Coagulase-Negative Staphylococcus/Mammaliicoccus from Retail Ground Meat: Identification of Broad Genetic Diversity in Fosfomycin Resistance Gene fosB.

Staphylococcus is a major bacterial species that contaminates retail meat products. The objective of this study was to clarify the prevalence, antimicrobial resistance and genetic determinants of Staphylococcus/Mammaliicoccus species in retail ground meat in Japan. From a total of 146 retail ground meat samples (chicken, pork, mixed beef/pork) purchased during a 5-month period, 10 S. aureus and 112 isolates of coagulase-negative staphylococcus (CoNS)/Mammaliicoccus comprising 20 species were recovered. S. aureus isolates were classified into five genetic types, i.e., coa-IIa/ST5, coa-VIc/ST352 (CC97), coa-VIIb/ST398, coa-Xa/ST15, and coa-XIc/ST9, which were all related to those of livestock-associated clones. All the staphylococcal isolates were mecA-negative and mostly susceptible to all the antimicrobials tested, except for ampicillin among S. aureus (resistance proportion; 50%). Among CoNS, the fosfomycin resistance gene fosB was prevalent (30/112; 26.8%), primarily in S. capitis, S. warneri, and S. saprophyticus. Phylogenetic analysis of fosB revealed the presence of seven clusters, showing broad diversity with 65-81% identity among different clusters. In the CoNS isolates from ground meat samples, fosB was assigned into three clusters, and S. saprophyticus harbored the most divergent fosB with three genetic groups. These findings suggested the circulation of multiple fosB-carrying plasmids among some CoNS species.

Clonal diversity of Clostridium perfringens human clinical isolates with various toxin gene profiles based on multilocus sequence typing and alpha-toxin (PLC) typing.

OBJECTIVES: Clostridium perfringens is a common anaerobic pathogen causing enteritis/enterocolitis and wound infections in humans. We analyzed clonal diversity and toxin gene prevalence in C. perfringens clinical isolates from humans in northern Japan. METHODS: Prevalence of nine toxin genes was analyzed for 585 C. perfringens isolates from patients collected for 20-month period between May 2019 and December 2020 by molecular methods. Sequence type (ST) based on multilocus sequence typing (Xiao's scheme) and alpha-toxin (PLC) sequence type were determined for a total of 124 isolates selected in the present study along with those in our previous study (2017-2018). RESULTS: Toxinotypes A (68.2%) was the most frequent, followed by F (31.6%), and G (0.2%), while additional toxin genes encoding binary enterotoxin (BEC/CPILE) and beta2 toxin were identified in one and six isolates, respectively. Among the 124 isolates with various toxin gene profiles, 62 STs including 53 novel types were identified, revealing the presence of six clonal complexes (CCs) consisting of 27 STs. Most of enterotoxin gene (cpe)-positive isolates belonged to CC36, CC41, and CC117. Based on 22 key amino acids in alpha toxin sequence, four PLC types (I-IV) including 21 subtypes were classified, and their relation to individual STs/CCs was clarified. Two isolates harboring bec/cpile belonged to different STs (ST95, ST131) and PLC types (If, IVb), indicating distribution of this toxin gene to distinct lineages. CONCLUSIONS: The present study revealed the diversity in C. perfringens clones of human origin with various toxin gene profiles represented by ST/CC and PLC type.

Oral candidiasis caused by ciclesonide in a patient with COVID-19 pneumonia: A case report and literature review.

Steroid has recently been reported as a treatment for new coronavirus disease (COVID-19). The incidence of oropharyngeal candidiasis due to the inhaled steroid ciclesonide is lower than that due to other inhaled steroids. We report the first case of oral candidiasis with COVID-19 pneumonia using ciclesonide. A 75-year-old man was hospitalized for COVID-19 pneumonia. After admission, an oral combination of lopinavir/ritonavir was administered, and ciclesonide was inhaled for 7 days. On the 14th day of hospitalization, white plaque was found in his oral mucosa. Candida albicans was identified by oral bacterial tests, and amphotericin B was initiated. On the 35th hospital day, negative result for C. albicans was confirmed. Intraoral monitoring and intervention by dental care workers are considered important for the prevention of infectious complications induced by corticosteroids.

Endoscopically-assisted intraoral resection of osteochondroma of the mandibular condyle with a piezoelectric surgical device.

Background: Osteochondromas of the mandibular condyle show facial asymmetry and malocclusion. Because condylar osteochondromas are generally resected in a preauricular approach with risks of facial nerve injury and visible scar, the authors report endoscopically assisted intraoral resection of osteochondroma of the mandibular condyle with a piezoelectric surgical device.Case presentation: A 38-year-old woman presented with malocclusion and facial asymmetry caused by deviation of the chin to the left. Computed tomography showed a hyperdense, well-circumscribed mass arising from the medial aspect of the right mandibular condyle with resorption of the skull base. The patient underwent an endoscopically-assisted intraoral condylectomy with a piezoelectric surgical device. The postoperative course was uneventful without trismus, malocclusion, or facial asymmetry, and there was no recurrence 4 years after surgery.Conclusion:Endoscopically assisted intraoral resection of osteochondroma of the mandibular condyle with a piezoelectric surgical device is a minimally invasive and safe surgery.

Actinomycotic osteomyelitis with proliferative periostitis arising in the mandibular ramus: an unusual case with spontaneous bone regeneration after coronoidectomy.

Actinomycotic osteomyelitis is an aggressive and persistent disease capable of invading and destroying bone, and chronic osteomyelitis with proliferative periostitis represents new bone formation with periosteal reaction. We report a rare case of actinomycotic osteomyelitis with proliferative periostitis arising in the mandibular ramus and spontaneous bone regeneration after coronoidectomy. A 14-year-old girl was referred for swelling in the right parotid-masseteric region and severe trismus. Contrast-enhanced CT revealed that heterogenous enhancement of the right masseter muscle, and a reactive bone formation over the lateral cortex of the right mandibular ramus and osteolysis of the condyle were seen in plain CT. MRI showed that the mandibular ramus was a low-signal intensity and the reactive bone on the ramus was signal intensity similar to muscle on T1-weighted images. The lesion was clinically and radiologically diagnosed as chronic osteomyelitis of the mandibular ramus. However, a biopsy was performed intraorally under general anesthesia to rule out a malignant bone tumor, and pathological examination showed fibrous bone and Actinomyces druses. Finally, the lesion was diagnosed as actinomycotic osteomyelitis with proliferative periostitis. She underwent image-guided intraoral removal of impacted right third molar and reactive proliferative bone on the right mandibular ramus under general anesthesia. To improve trismus, coronoidectomy also was performed. After the discharge, AMPC was administrated intraorally for 7.5 months. Postoperative panoramic radiograph and CT showed the right mandibular angle resorption and coronoid process regeneration. There was no recurrence of mandibular osteomyelitis 7 years after surgery.

Prognostic factors and treatment outcomes of advanced maxillary gingival squamous cell carcinoma treated by intra-arterial infusion chemotherapy concurrent with radiotherapy.

BACKGROUND: The aim of this study was to evaluate the prognostic factors and treatment outcomes of advanced maxillary gingival squamous cell carcinoma (SCC) treated with intra-arterial infusion chemotherapy concurrent with radiotherapy. METHODS: A total of 46 patients were reviewed retrospectively in this study. The treatment schedule comprised intra-arterial chemotherapy (total, 60 mg/m2 docetaxel and 150 mg/m2 cisplatin) and three-dimensional computed tomography based, daily conventional radiotherapy (total, 60 Gy/30 fr) for 6 weeks. RESULTS: The median follow-up period was 40 months (range, 3-110 months). The 3-year overall survival and locoregional control rates for all patients were 64.3% and 84.3%, respectively. The OS rate of the patients with N0-1 was significantly higher than that of the patients with N ≥ 2 (P < .05). No grade 5 toxicities were observed. CONCLUSIONS: Intra-arterial infusion chemotherapy concurrent with radiotherapy was effective for advanced maxillary gingival SCC.

Swallowing function in advanced tongue cancer patients before and after bilateral neck dissection following superselective intra-arterial chemoradiotherapy for organ preservation: a case-control study.

OBJECTIVE: This study aimed to evaluate swallowing function in advanced tongue cancer patients before and after bilateral neck dissection following superselective intra-arterial chemoradiotherapy (CRT). METHODS: A videofluoroscopic swallowing study (VFSS) was used to evaluate swallowing function in 10 patients with advanced tongue cancer before and after bilateral neck dissection. RESULTS: Laryngeal penetration increased in the postoperative VFSS. Temporal analysis comparing two time points revealed that, after surgery, oral transit time increased significantly, but there was no difference in pharyngeal delay time or pharyngeal transit time. Spatial analysis revealed significant decreases after surgery in the maximum distance of upper esophageal sphincter (UES) opening, the maximum distance of hyoid bone movement in both the anterior and superior direction, and the maximum velocity of hyoid bone movement. CONCLUSIONS: Laryngeal penetration and aspiration increased as a result of limited hyoid movement and diminished UES opening after bilateral neck dissection following superselective intra-arterial CRT for advanced tongue cancer.

Airway obstruction caused by pharyngolaryngeal swelling after intraoral removal of a submandibular gland stone.

Intraoral removal of a submandibular gland stone is less invasive than submandibulectomy, with no life-threatening airway complications reported until now. We report a case involving airway obstruction caused by pharyngolaryngeal swelling after intraoral removal of a submandibular gland stone. A 31-year-old man with a left submandibular gland stone underwent intraoral removal of the stone under general anesthesia and was discharged 1 day after surgery. That night, he was transported back to our hospital by ambulance for dyspnea. Because computed tomography showed pharyngolaryngeal swelling, he was intubated and managed by a ventilator. Four days later, the pharyngolaryngeal swelling had mostly resolved and he was extubated and discharged. Surgeons should be vigilant of the potential risk of airway complications following an intraoral approach for submandibular gland stone removal.

Chemoradiotherapy using retrograde superselective intra-arterial infusion for tongue cancer: Analysis of therapeutic results in 118 cases.

OBJECTIVES: To evaluate the therapeutic results and rate of organ preservation in patients with squamous cell carcinoma of the tongue treated with retrograde superselective intra-arterial chemoradiotherapy. MATERIALS AND METHODS: Between June 2006 and June 2015, 118 patients with tongue cancer were treated with intra-arterial chemoradiotherapy. Treatment consisted of radiotherapy (total 50-70 Gy) and daily concurrent intra-arterial chemotherapy (docetaxel, total 50-70 mg/m2; cisplatin, total 125-175 mg/m2) for 5-7 weeks. Locoregional control and overall survival rates were calculated by the Kaplan-Meier method. Cox's proportional hazards model was used for both univariate and multivariate analyses. RESULTS: The median follow-up for all patients was 38.5 months (range, 3-129 months). After intra-arterial chemoradiotherapy, primary site complete response was achieved in 113 (95.8%) of 118 cases. Three-year locoregional control and overall survival rates were 80.3% and 81.5%, respectively. Grade 3 or 4 toxicities included neutropenia in 16.1% and mucositis in 87.3%. Grade 3 toxicities included anemia in 12.7%, thrombocytopenia in 3.4%, nausea/vomiting in 3.4%, dermatitis in 45.7%, dysphagia in 74.6%, and fever in 2.5% of patients. Late toxicity consisting of grade 3 osteoradionecrosis of the jaw occurred in 4.2% of patients. On univariate analysis, T stage and overall stage were significantly associated with locoregional control, and N stage and overall stage were significantly associated with overall survival. On multivariate analysis, the only significant predictor of overall survival was overall stage classification. CONCLUSION: Retrograde superselective intra-arterial chemoradiotherapy for tongue cancer provided good overall survival and locoregional control.