Analysis of the Spectrum of Common Pathogens and the Resistance of Mycoplasma in Sialidase-Positive Bacterial Vaginosis.

BACKGROUND: The objective of this study is to understand the characteristics of the common spectrum of pathogen and the resistance of Mycoplasma in Sialidase-positive bacterial vaginosis. METHODS: The vaginal secretion specimens collected from August 2018 to October 2018 for the analysis of bacterial vaginosis (BV) were subjected to various techniques. These included routine leukorrhea examination, bacterial vaginosis sialidase testing, routine culture for common pathogens, mass spectrometry identification, and Mycoplasma resistance testing. RESULTS: A total of 238 patients with BV were identified. The cleanliness grading was mostly clean (+) and clean (2+), accounting for 38.24% and 30.67%, respectively. The bacterial vaginosis test for vaginal secretions showed leukocyte esterase positivity in 220 cases, resulting in a positivity rate of 92.44%. The spectrum of routine culture was analyzed and divided into four groups: A, B, C, and D. Group A consisted of Candidal vaginitis (13.45%); group B consisted of Gardnerella vaginalis vaginitis (32.77%); group C consisted of gram-negative bacillus vaginitis (46.22%); and group D consisted of Streptococcus agalactiae vaginitis (7.56%). The identification and antimicrobial susceptibility testing results for Mycoplasma showed a high detection rate of BV, with a positivity rate of 86.13%. There was a high sensitivity to tetracyclines for Ureaplasma urealyticum and Mycoplasma hominis, but a high resistance to macrolides and quinolones. CONCLUSIONS: Bacterial vaginosis existed in various complex forms, including Candida, Gardnerella vaginalis, Gram-negative bacillus, and Streptococcus agalactiae types. Moreover, there was an increasing trend of multi-drug resistance in Mycoplasma hominis. Therefore, it is crucial to pay attention to this condition and make accurate judgments based on the etiological characteristics and common antimicrobial susceptibility tests. This will enable the implementation of effective therapeutic interventions.

Microbiology and Clinical Outcome of Bloodstream Infections in Patients After Hematopoietic Stem Cell Transplantation.

Purpose: Patients after hematopoietic stem cell transplantation (HSCT) are often followed by bloodstream infections (BSIs). BSI is an important cause of non-relapse mortality (NRM) in HSCT patients. Methods: We conducted a retrospective cohort study of patients (aged >14 years) who underwent HSCT at our hospital from 2017 to 2021. Population characteristics, BSI microbiology, resistance to common antibiotics, and 30-day all-cause mortality were analyzed. Results: Of 3054 patients, 169 (5.5%) had BSIs after HSCT. Male, not in complete remission at transplantation and longer duration of neutropenia were risk factors for the development of BSI after HSCT. These BSIs were Gram-negative bacterial (n=123, 69.49%), Gram-positive bacterial (n=27, 15.25%), fungal (n=11, 6.36%), and polymicrobial (n=16, 9.25%). Among the Gram-negative bacteria, the proportions of isolates resistant to ceftazidime, cefepime, and piperacillin-tazobactam were similar (72.93%, 74.80%, and 77.42%, respectively). The overall drug resistance rates of amikacin and imipenem were 16.13% and 43.90%, respectively. Staphylococcus isolates were methicillin-resistant. In Enterococcus isolates, the penicillin resistance rate was 84.62%. Eleven isolates of Candida tropicalis were resistant to fluconazole and were sensitive to amphotericin B and flucytosine. The 30-day all-cause mortality rate of the 169 patients with BSIs was 8.88%. The 30-day all-cause mortality of patients with Gram-negative bacterial BSIs was 7.32%, 25.00% for polymicrobial BSIs, and 36.36% for fungal BSIs. The 30-day all-cause mortality of patients with fungal BSIs was significantly higher than that of patients with Gram-negative (P=0.0023) and Gram-positive bacteria (P=0.0023). Fungal BSI and non-Hodgkin's lymphoma (NHL) were associated with higher 30-day mortality. Conclusion: Our study reveals the microbiological characteristics and 30-day all-cause mortality in patients with bloodstream infections after HSCT. Our data provides strong support for empirical antimicrobial therapy and infection prevention strategies for patients with BSIs after HSCT.

Risk factors and molecular epidemiology of bloodstream infections due to carbapenem-resistant Klebsiella pneumoniae.

PURPOSE: Carbapenem-resistant Klebsiella pneumoniae (CRKP) is emerging as a worldwide public health concern; however, molecular epidemiological surveillance of clinical CRKP bloodstream infection (BSI) in China is limited. We conducted a retrospective observational study to assess risk factors and the molecular epidemiology of CRKP BSI. METHODS: We reviewed the medical records of enrolled patients to assess risk factors of CRKP BSI. Characteristics of CRKP isolates were analyzed by whole genome sequencing and Kleborate. Evolutionary diversification in CRKP isolates was described through Single Nucleotide Polymorphisms analysis and phylogenetic tree construction. RESULTS: We found that prior ICU hospitalization and use of carbapenems were independent risk factors for CRKP BSI. The main CRKP sequence type (ST) and capsular serotype were ST11 and KL64, and KPC-2 was the most prevalent enzyme type of carbapenemase-carrying Klebsiella pneumoniae. The most prevalent aerobactin and yersiniabactin of ST11-CRKP were iuc-1 and ybt9 ICEKp3, as for KL64-CRKP. Phylogenomic analysis showed that the antibacterial resistance genes on plasmids were highly consistent, but the genetic background of the chromosomes was still different. CONCLUSIONS: Our findings are important for hospitals, allowing them to limit dissemination of CRKP and optimize antibiotic administration.

Polymyxin B resistance rates in carbapenem-resistant Pseudomonas aeruginosa isolates and a comparison between Etest® and broth microdilution methods of antimicrobial susceptibility testing.

Polymyxin B has been considered to be the last line of defense for life-threatening infections caused by multiple drug resistant gram-negative pathogens, including carbapenem-resistant Pseudomonas aeruginosa (CRPA). The present study analyzed CRPA resistance to polymyxin B in the Suzhou district of China. Additionally, polymyxin B resistance rates were compared in different parts of the world to determine global trends. The present study also assessed the reliability and effectiveness of the Etest® in a clinical setting, as laboratories lack a reliable and efficient susceptibility test for polymyxin B. The susceptibility rate of polymyxin B reached 96.0%, which is in accordance with results obtained from the United States of America, Europe, Africa and the majority of Asian countries. However, the rate of polymyxin B non-susceptibility (resistant or intermediate) in Singapore is 0.53 (95% confidence interval, 0.12-0.93). In addition, the susceptibility rate of polymyxin B determined via Etest® was not significantly increased compared with that determined via broth microdilution (98.0 vs. 96.0%; P=0.558). Essential and categorical agreement rates reached 98.0%. In conclusion, the polymyxin B resistance rate of CRPA isolates is relatively low in the majority of countries, with the exception of Singapore. Furthermore, Etest® may be a reliable clinical method for the measurement of polymyxin B resistance in CRPA isolates.

Supine versus semi-Fowler's positions for tracheal extubation in abdominal surgery-a randomized clinical trial.

BACKGROUND: Tracheal extubation is commonly performed in the supine position. However, in patients undergoing abdominal surgery, the supine position increases abdominal wall tension, especially during coughing and deep breathing, which may aggravate pain and lead to abdominal wound dehiscence. The semi-Fowler's position may reduce abdominal wall tension, but its safety and comfort in tracheal extubation have not been reported. We aimed to evaluate the safety and comfort of different extubation positions in patients undergoing abdominal surgery. METHODS: We enrolled 141 patients with an American Society of Anesthesiologists grade of I-III who underwent abdominal surgery. All patients were anesthetized with propofol, fentanyl, cisatracurium, and sevoflurane. After surgery, all patients were transferred to the post-anesthesia care unit (PACU). Patients were then randomly put into the semi-Fowler's (n = 70) or supine (n = 71) position while 100% oxygen was administered. The endotracheal tube was removed after the patients opened their eyes and regained consciousness. Vital signs, coughing, and pain and comfort scores before and/or after extubation were recorded until the patients left the PACU. RESULTS: In comparison with the supine position, the semi-Fowler's position significantly decreased the wound pain scores at all intervals after extubation (3.51 ± 2.50 vs. 4.58 ± 2.26, 2.23 ± 1.68 vs. 3.11 ± 2.00, 1.81 ± 1.32 vs. 2.59 ± 1.88, P = 0.009, 0.005 and 0.005, respectively), reduced severe coughing (8[11.43%] vs. 21[29.58%], P = 0.008) and bucking after extubation (3[4.29%] vs. 18[25.35%], P < 0.001), and improved the comfort scores 5 min after extubation (6.11 ± 2.30 vs. 5.17 ± 1.78, P = 0.007) and when leaving from post-anesthesia care unit (7.17 ± 2.27 vs. 6.44 ± 1.79, P = 0.034). The incidences of vomiting, emergence agitation, and respiratory complications were of no significant difference. CONCLUSION: Tracheal extubation in the semi-Fowler's position is associated with less coughing, sputum suction, and pain, and more comfort, without specific adverse effects when compared to the conventional supine position. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR1900025566 . Registered on 1st September 2019.

In Vivo Evaluation of the Ameliorating Effects of Small-Volume Resuscitation with Four Different Fluids on Endotoxemia-Induced Kidney Injury.

Acute kidney injury associated with renal hypoperfusion is a frequent and severe complication during sepsis. Fluid resuscitation is the main therapy. However, heart failure is usually lethal for those patients receiving large volumes of fluids. We compared the effects of small-volume resuscitation using four different treatment regimens, involving saline, hypertonic saline (HTS), hydroxyethyl starch (HES), or hypertonic saline hydroxyethyl starch (HSH), on the kidneys of rats treated with lipopolysaccharide (LPS) to induce endotoxemia. LPS injection caused reduced and progressively deteriorated systemic (arterial blood pressure) and renal hemodynamics (renal blood flow and renal vascular resistance index) over time. This deterioration was accompanied by marked renal functional and pathological injury, as well as an oxidative and inflammatory response, manifesting as increased levels of tumor necrosis factor-α, nitric oxide, and malondialdehyde and decreased activity of superoxide dismutase. Small-volume perfusion with saline failed to improve renal and systemic circulation. However, small-volume perfusion with HES and HSH greatly improved the above parameters, while HTS only transiently improved systemic and renal hemodynamics with obvious renal injury. Therefore, single small-volume resuscitation with HES and HSH could be valid therapeutic approaches to ameliorate kidney injury induced by endotoxemia, while HTS transiently delays injury and saline shows no protective effects.

Dual Effects of Bilirubin on the Proliferation of Rat Renal NRK52E Cells and ITS Association with Gap Junctions.

OBJECTIVE: The effect of bilirubin on renal pathophysiology is controversial. This study aimed to observe the effects of bilirubin on the proliferation of normal rat renal tubular epithelial cell line (NRK52E) and its potential interplay with gap junction function. METHODS: Cultured NRK52E cells, seeded respectively at high- or low- densities, were treated with varying concentrations of bilirubin for 24 hours. Cell injury was assessed by measuring cell viability and proliferation, and gap junction function was assessed by Parachute dye-coupling assay. Connexin 43 protein was assessed by Western blotting. RESULTS: At doses from 17.1 to 513µmol/L, bilirubin dose-dependently enhanced cell viability and colony-formation rates when cells were seeded at either high- or low- densities (all p<0.05 vs. solvent group) accompanied with enhanced intercellular fluorescence transmission and increased Cx43 protein expression in high-density cells. However, the above effects of BR were gradually reversed when its concentration increased from 684 to 1026µmol/L. In high-density cells, gap junction inhibitor 12-O-tetradecanoylphorbol 13-acetate attenuated bilirubin-induced enhancement of colony-formation and fluorescence transmission. However, in the presence of high concentration bilirubin (1026µmol/L), activation of gap junction with retinoid acid decreased colony-formation rates. CONCLUSION: Bilirubin can confer biphasic effects on renal NRK52E cell proliferation potentially by differentially affecting gap junction functions.