Successful Treatment of Postneurosurgical Ventriculitis Caused by Extensively Drug-resistant Acinetobacter baumannii in a Child: Case Report

Introduction: The incidence of postneurosurgical Acinetobacter baumannii ventriculitis/meningitis, primarily due to drug-resistant strains, has increased considerably in recent years. However, limited therapeutic options are available because most antibiotics poorly penetrate the blood-brain barrier, especially in pediatric patients. Case Presentation: A five-year-old boy developed ventriculitis due to extensively drug-resistant A. baumannii (XDRAB) after bilateral frontal external ventricular drainage for spontaneous intraventricular hemorrhage. The boy was safely and successfully treated with intraventricular (IVT)/intrathecal (ITH) polymyxin B together with intravenous tigecycline plus cefoperazone/sulbactam. Conclusions: In the present case, postneurosurgical XDRAB ventriculitis was closely associated with intraventricular hemorrhage and the placement of external ventricular drainage. IVT/ITH polymyxin B combined with intravenous tigecycline and cefoperazone sulbactam could be a therapeutic option against XDRAB ventriculitis in children.

Changing Trends of Candida Species and Antifungal Susceptibility Profile of Candida Bloodstream Isolates: A 5-Year Retrospective Survey

Background: Candida species have emerged as one of the most common causes of bloodstream infections (BSIs). There are limited data on the distribution of Candida spp. and susceptibility by year. Objectives: In this study, we analyzed changes in the distribution of Candida spp. and their antifungal susceptibility profiles from blood cultures. Methods: Records from January 2016 to December 2020 were obtained from the microbiology laboratory in Istanbul. Antifungal susceptibility tests were performed using the VITEK 2 compact system and evaluated according to EUCAST breakpoints. A total of 241 unique candidemia episodes were included in this study. Results: Candida albicans was the predominant pathogen (n = 95, 39.42%), followed by C. parapsilosis (n = 82, 34.02%), C. glabrata (n = 18, 7.47%), C. tropicalis (n = 17, 7.05%), C. krusei (n = 15, 6.22%), and other Candida spp. (n = 14, 5.79%). There was no statistically significant difference in the percentage of episodes of Candida spp. After data analysis, a tendency to shift from C. albicans to C. parapsilosis was observed in the period analyzed in this study. Candida albicans was the most common species in intensive care units (ICUs), hematology and hemopoietic stem cell transplantation units, and surgical clinics, with C. parapsilosis predominant in medical clinics. In general, micafungin susceptibility was the highest, and fluconazole was the lowest. There was reduced sensitivity to fluconazole and voriconazole for C. albicans and C. parapsilosis over 5 years. Conclusions: Detecting changes in the distribution of Candida spp. and antifungal susceptibility over time will lead to the selection of appropriate empirical therapy and monitor phenomena of antifungal resistance. Empirical treatment with antifungal agents is associated with high costs, toxicities, and risk of antifungal resistance. Therefore, it is mandatory to determine and monitor Candida spp. and antifungal susceptibility testing to select appropriate antifungal agents.

A New Colorimetric Method for Rapid Detection of Antibiotic Resistance in Escherichia coli Isolates

Background: The quick diagnosis and early initiation of antibiotic therapy in bacteria-induced infections is of paramount importance. Accordingly, the rapid identification of the causative agent, the short-term results of antibiotic sensitivity, the selection and use of right antibiotics for treatment further highlights the significance of this issue. Objectives: This study aimed to develop a new susceptibility testing method to provide rapid results in Escherichia coli clinical isolates and report the antibiotic susceptibility test results to clinicians in a short period. Methods: In the study, one hundred and ten E. coli clinical isolates were tested. In this regard, antibiotics recommended by the "Clinical and Laboratory Standards Institute (CLSI)" for testing the sensitivity of E. coli isolates, including amoxicillin-clavulanate, cefixime, ceftriaxone, ertapenem, ciprofloxacin, gentamicin, trimethoprim-sulfamethoxazole, and nitrofurantoin were tested. For quality control, E. coli ATCC25922, E. coli ATCC35218, Staphylococcus aureus ATCC29213, and E. coli 13846NTCC strains were used. The broth microdilution method recommended by CLSI was used as the reference method. Minimum inhibitory concentration values were determined, and antimicrobial susceptibilities were then determined according to the “European Committee on Antimicrobial Susceptibility Testing (EUCAST)” criteria. In the next phase, the results of the resazurin microplate method (RMM) were compared. Results: The comparison of the RMM developed in the present study with the reference method revealed that the calculated essential agreement ratios for eight antibiotics varied from 82.72 to 100%, and the categorical agreement values ranged from 95.45 to100%. Conclusions: According to the findings, the RMM results were highly in agreement with the results of the reference method. RMM allows the detection of antibiotic susceptibility quickly (e.g., within 5 hours) as such it is preferred, especially for laboratories with limited facilities. However, further multi-center studies are recommended to use this method in routine laboratories.

Reverse Transcription Loop-Mediated Isothermal Amplification Assay with High Sensitivity to Rapid Detection of Viable Salmonella in Foods

Background: Salmonella is one of the main foodborne bacterial pathogens, causing diseases and death. The study used reverse transcription loop-mediated isothermal amplification (RT-LAMP) to detect Salmonella. Objectives: To design six primers and detect Salmonella using RT-LAMP to facilitate the rapid detection of pathogenic bacteria in food. Methods: We designed six primers based on the gene coding sequences of inv A, specific to Salmonella. Each reaction solution contained 6.0 mM MgSO4, 1 M betaine, 1.6 mM dNTPs, 160 U/mL Bst DNA polymerase, 0.2 μM of both external primers, 0.8 μM of both internal primers, and 0.2 μM of both loop primers. The reaction temperature was 65°C. Results: Our amplified products were separated by 2% agarose gel electrophoresis. The detection limit was 10 CFU per reaction. Conclusions: RT-LAMP exhibited the same accuracy as the GB assay in detecting Salmonella in foods. RT-LAMP was highly specific and sensitive; hence, it may serve as an effective tool in detecting Salmonella.

Multipathogen Detection in Patients with Respiratory Tract Infection: Identification of Non-respiratory Viruses Using Multiplex Real-time Polymerase Reaction

Background: Due to the overlapping clinical characteristics of respiratory tract infections (RTIs) and the unavailability of appropriate diagnostic techniques, the diagnosis of RTIs is controversial. Objectives: The study aimed to prompt the diagnosis of RTIs using commercial multiplex real-time PCR. Methods: The survey undertook for two years (2019 - 2020) on 144 flu-negative immunocompetent outpatients. Respiratory samples were examined by multiplex PCR assays. Results: Study population consisted of females (n = 77, 53.5%) and males (n = 67, 46.5%). The mean age was 42.8 ± 23.7 years. Thirty-one (21.5%) patients were infected with only one viral or bacterial infection. Eighty-two (57%) were infected with more than one pathogen. Ninety-five (37%) and 161 (62%) tests were positive for bacterial and viral pathogens, respectively. Community-acquired Pneumonia (CAP) and atypical CAP pathogens included 17% and 10% of respiratory specimens, respectively. The predominant pathogens consisted of Human Herpes Virus 7 (HHV-7) (n = 38, 15.5%), Epstein-Barr Virus (EBV) (n = 34, 13.8%), Mycoplasma pneumoniae (n = 24, 9.8%), and Human Herpes Virus 6 (HHV-6) (n = 21, 8.5%). There were associations between pathogen findings and special age categories. Fever, cough, dyspnea, and hemoptysis were associated with certain pathogens. There was no substantial difference between viral and bacterial Ct concerning gender, age group, and comorbidities. Conclusions: Multiplex diagnostic assays significantly increased the rate of appropriate diagnosis of respiratory pathogens. However, further investigation is needed to find non-respiratory viruses' significance in respiratory specimens of immunocompetent symptomatic patients.

Prevalence of Hepatitis C Infection and its Genotypes in Suspected Hemodialysis Patients, Southwest of Iran

Background: Hemodialysis patients are more prone to Hepatitis C Virus (HCV) infection due to the need for long-term hemodialysis and blood transfusions. Objectives: The present study aimed to determine the HCV infection burden, viral load, and genotype pattern in hemodialysis patients referred to a research center from 2011 to 2018. Methods: Among 131 hemodialysis patients with suspected HCV infection, referred to Prof. Alborzi Clinical Microbiology Research Center, Shiraz, Iran, from 2011 to 2018, the HCV rate was assessed with the enzyme-linked immunosorbent assay and the HCV RNA load and genotypes by one-step TaqMan real-time PCR. Results: The prevalence of HCV-Ab positivity was 29% among hemodialysis patients, of whom 21 (57%) were HCV RNA-positive. In the rest of the hemodialysis patients who were HCV-Ab-negative, the HCV RNA was detected in five (12%) patients. Genotype 3 (Gt-3) was the most prevalent one detected in 50% of the patients whose genotypes were determined. Also, the HCV viral load in HCV-seropositive patients was generally higher than that in HCV-seronegative ones. Conclusions: This study showed that high HCV infection and different genotype patterns among hemodialysis patients compared to the general population are the main predictors of HCV infection, which indicates healthcare facility transmission because of inappropriate infection management practices.

Five-year Surveillance of Antimicrobial Resistance Changes and Epidemiological Characteristics in Pseudomonas aeruginosa: A Retrospective Study in a Chinese City Hospital

Background: In recent years, the widespread use of antibiotics has resulted in increased rates of antibiotic resistance (ABR). Pseudomonas aeruginosa is one of the most important opportunistic pathogens causing hospital-acquired infections. Pseudomonas aeruginosa has continuously increased resistance to commonly used clinical antimicrobial drugs, bringing great difficulties to clinical treatment. Objectives: This retrospective study investigated the epidemiological characteristics of P. aeruginosa and changes in ABR over a 5-year period at a hospital in Shandong Province, China. Methods: Pseudomonas aeruginosa strains were collected from 2015 to 2019. The antimicrobial susceptibility testing employed the Kirby-Bauer disk diffusion method and the broth microdilution method (VITEK-2 compact system), according to the guidelines by the Clinical and Laboratory Standards Institute. Data were analyzed using WHONET 5.6 and SPSS V. 21.0 software. Results: A total of 3,324 P. aeruginosa strains were isolated from clinical specimens (604, 631, 700, 595, and 794 strains from 2015 to 2019, respectively). The highest P. aeruginosa detection rates were from respiratory tract specimens (72.54%). The highest resistance was seen in aztreonam, followed by ciprofloxacin, levofloxacin, and imipenem. The isolation rates for carbapenem-resistant P. aeruginosa (CRPA) and multidrug-resistant P. aeruginosa (MDRPA) ranged from 15.21 - 18.38% and 17.31 - 27.31%, respectively. Also, the isolation rates for extensively drug-resistant P. aeruginosa (XDRPA) ranged from 1.86 - 3.52%. Conclusions: The main sources of the P. aeruginosa isolates were older adult patients with chronic respiratory diseases. The isolation rates for CRPA, MDRPA, and XDRPA strains decreased over the 5-year period. However, the drug resistance situation remains a serious concern. Hence, continued infection control and antimicrobial stewardship and basic and clinical research on bacterial resistance are essential.

Evaluation of Anti-SARS-CoV-2 IgG Antibody in Healthcare Professionals Infected with COVID-19

Background: The knowledge of antibody’s significance and frequency in patients cured of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is extremely limited. Objectives: This study aimed to evaluate anti-SARS-CoV-2 IgG antibodies in patients exposed to SARS-CoV-2. Methods: Healthcare professionals infected with SARS-CoV-2 were enrolled in this study. The levels of anti-SARS-CoV-2 IgG antibodies were detected 15 days after the onset of symptoms and five months later. Results: A total of 167 patients with coronavirus disease 2019 (COVID-19) were evaluated, including 119 (71.3%) females and 48 (28.7%) males. Of the 88 polymerase chain reaction (PCR)-positive patients, 55 (62.5%) had IgG-positive antibodies, and of the 79 reverse transcriptase (RT)-PCR-negative patients, 12 (16.9%) had IgG-positive antibodies. Out of 23 anosmia cases, 19 (82.6%) had positive antibodies. There was a significant relationship between anosmia and positive antibody (P = 0.001), but there was no correlation between antibody titers and gender and other disease symptoms. Immortally, 63 (94%) cases demonstrated high levels of anti-SARS-CoV-2 IgG antibodies after five months of infection. Moreover, 6.5% (N = 11) of the total population were re-infected with COVID-19 six months later. Conclusions: Overall, anti-SARS-CoV-2 IgG antibodies detection may be an appropriate method to identify suspected patients with a negative RT-PCR test. Antibodies can remain high in most infected patients for up to five months after infection. Moreover, anosmia seems to be a valuable diagnostic factor, and the healthcare system should implement isolation measures for patients with anosmia.

Characteristics of Intestinal Flora in Pregnant Women with Mild Thalassemia Revealed by Metagenomics

Background: At present, there is no report that the intestinal flora of pregnant women with mild thalassemia is different from that of healthy pregnant women. Objectives: This study compared the composition and changes of the intestinal flora of pregnant women with mild thalassemia to those of healthy pregnant women using metagenomic sequencing technology and evaluated the potential microecological risk for pregnant women and the fetus. Methods: The present study was carried out on 14 mild thalassemia pregnant women with similar backgrounds in the Affiliated Hospital of Putian University, Fujian, China. In the same period, 6 healthy pregnant women were selected as the control group. The genomic deoxyribonucleic acid was extracted from the sable stool samples of pregnant women. Illumina HiSeq sequencing technology was adopted after library preparation. Prodigal software (ver 2.6.3, Salmon software (ver 1.6.0, and Kraken software (ver 2) were used to analyze the sequence data. Moreover, analysis of variance and Duncan’s multiple-comparison test or Wilcoxon rank-sum test were used as statistical methods. Results: The characteristics of the intestinal flora of pregnant women with mild thalassemia differed significantly from those of healthy pregnant women, showing an increase in some conditionally pathogenic bacteria (e.g., Prevotella stercorea rose and Escherichia coli) and a decrease in some probiotic bacteria, which might affect pregnant women and cause physiological function damage to their offspring by changing metabolic pathways; however, further validation is needed. Conclusions: The diversity and composition of intestinal flora in pregnant women with mild thalassemia vary significantly from those in healthy pregnant women, especially at the genus and species levels, representing more profound alterations in intestinal microecology.

Evaluation of Seroprevalence of Hepatitis B Virus and Hepatitis C Virus in Reference Center Hospital in Turkey's Southeast Anatolia Among Patients Referred for Major or Minimally Invasive Surgery: Last Decade Experience in a Previously High Prevalence Area

Background: There is a high worldwide prevalence of chronic Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) infections, among the significant causes of liver-related morbidity and mortality. Objectives: We aimed to determine the prevalence of HBV and HCV in a referral center hospital in Southeast Anatolia among patients that applied for major or minimally invasive surgery. Methods: In a tertiary referral state hospital for general purposes, patients undergoing surgical procedures and serologic examinations for HBV and HCV were included in the study between January 2011 and September 2020. Results: In the general population, hepatitis B surface antigen (HBsAg) and anti-HBs were examined in 220,724 patients, and anti-HCV was examined in 186,017 patients. The mean age was 42.3 ± 20.2 years with a 51.8% male distribution. The frequency of positive HBsAg and anti-HCV in all patients was 9.4 and 0.9%, respectively. On the other hand, the frequency of positive HBsAg and anti-HCV was 4.2 and 0.7%, respectively, among patients admitted for a surgical procedure. The mean age was 46.1 ± 21.1 years with a slightly male predominance (54 vs. 46%). In this group, the frequency of positive HBsAg was higher in males (5.1%) while the lowest was in the 1 - 10 age range (0.4%) and the highest in the 41 - 50 age range (5.7%). Between 2011 and 2019, the prevalence of HBsAg positivity decreased from 6.4 to 4.0%, while anti-HCV positivity was similar in both genders, and its frequency increased with age. Conclusions: Between 2011 and 2020, the overall prevalence of HBV and HCV decreased in the Southeast Anatolia Region of Turkey.