Jundishapur Journal of Microbiology
Volume:16 Issue: 4, Apr 2023

 Currently, the emergence of extended-spectrum β-lactamase (ESBL)-producing bacteria is becoming a major threat to patients in the hospital and community. Such enzymes have been recently detected in Pseudomonas aeruginosa, but there is no epidemiological data on the prevalence of ESBL-producing clinical isolates in the hospitals of Ardabil City (Iran).

 This study aimed to determine the phenotypic and genotypic prevalence of class A ESBL-producing P. aeruginosa strains in Ardabil City.

 A total of 120 clinical isolates of P. aeruginosa collected from Ardabil hospitals were used in this study. Phenotypic detection of class A ESBL-producing P. aeruginosa isolates was performed using a double-disk synergy test. In addition, the detection of class A ESBL-encoding genes, including Pseudomonas extended resistant (PER), Vietnamese extended-spectrum β-lactamase (VEB), temoniera (TEM), sulfhydryl variable (SHV), cefotaximase (CTX-M), guyana extended-spectrum β-lactamase (GES), and Pseudomonas-specific enzyme (PSE), was performed using the polymerase chain reaction (PCR).

 The prevalence of class A ESBL-producing P. aeruginosa strains was 8.3% (10 out of 120) based on the double-disk synergy test. However, 40% (48 out of 120) of these isolates were found to carry genes encoding class A ESBLs based on PCR. Among 48 class A ESBL-positive strains, the prevalence of PSE, TEM, VEB, CTX-M, and PER genes were 64.6% (31/48), 25% (12/48), 4.2% (2/48), 4.2% (2/48), and 2% (1/48), respectively. However, the frequency of other class A ESBL genes (SHV and GES genes) was 0%.

 Our results confirmed the presence of class A ESBL-producing P. aeruginosa strains in the hospital environment of Ardabil. On the other hand, the use of molecular tests can be a more precise and reliable method than phenotypic ones to identify these resistant strains and prevent the emergence of antibiotic resistance and ensuing treatment failure.

 One of the leading causes of neonatal mortality in low- and middle-income countries (LMICs) is neonatal sepsis caused by carbapenem-resistant gram-negative bacteria.

 This study aimed to determine the frequency, bacterial profile, and outcome of carbapenem-resistant Gram-negative neonatal sepsis in southwest Iran.

 This 15-month retrospective cross-sectional descriptive study was conducted at a level 3 referral training hospital. The study included all neonates hospitalized from birth who had positive blood cultures for Gram-negative bacteria. Patients were divided into carbapenem-resistant and carbapenem-sensitive groups.

 During the study, Gram-negative bacteria were isolated from the blood cultures of 113 neonates. Positive Gram-negative bacteria blood cultures and carbapenem-resistant cases were 2.38% and 1.52%, respectively. In these cases, 66 (58.4%) of the infants were males, 100 (88.4%) were preterm, and 74 (65.4%) required mechanical ventilation within the first three days of life. The study found 45 (39.8%) infants with early-onset sepsis. Acinetobacter was the most common isolated organism, while Enterobacter had the lowest isolation rate. Carbapenem resistance was discovered in 72 (63.7%) positive blood cultures. Acinetobacter had the highest prevalence of carbapenem resistance, while Pseudomonas had the lowest. Mortality rates in infants infected with carbapenem resistance bacteria (CRB) were 89.3% compared to 10.7% in those infected with carbapenem-sensitive bacteria (CSB).

 The frequency of carbapenem-resistant Gram-negative sepsis in our ward was 1.52 percent of all admissions, and Acinetobacter bacteria was the most common cause of this type of neonatal sepsis. Infants infected with CRB had a higher mortality rate than those infected with CSB, 89.3% versus 10.7%.

 In the COVID-19 era, co-infections can lead to an increase in morbidity and mortality. Normal flora bacteria can transfer to the pulmonary tract and create bacterial co-infections. The nasal cavity is one of the main areas housing normal flora in the human body.

 In this study, we evaluated the prevalence and antibiotic resistance of gram-positive cocci in the pre– and post–COVID-19 eras among health care workers.

 We assessed 376 nasal swabs from the pre–COVID-19 era and 376 from the post–COVID-19 era. Conventional and molecular methods were used to identify bacterial types and evaluate antimicrobial resistance.

 The most common gram-positive cocci in the pre–COVID-19 samples were Staphylococcus aureus, S. epidermidis, S. capitis, S. hominis, S. haemolyticus, Streptococcus pneumoniae, and Enterococcus faecalis. In the post–COVID-19 samples, the most common gram-positive cocci were S. aureus, S. epidermidis, S. warneri, S. hominis, and E. faecalis. We observed higher resistance rates in post–COVID-19 samples, as well as resistance to linezolid and vancomycin in S. aureus, S. epidermidis, and S. hominis. Additionally, our isolates showed a high resistance rate to antiseptics.

 It seems that after the beginning of the COVID-19 pandemic, due to the change in the protective procedures in hospitals, the prevalence and variety of bacteria have decreased, but instead, they have been replaced by more pathogenic bacteria with higher antibiotic resistance.

 More and more variants of concern (VOCs) of SARS-CoV-2 continued to emerge in different regions worldwide.

 Studies on COVID-19 outbreaks caused by different VOCs are critical for understanding their infections in humans in different regions.

 In this descriptive study, the individual information of 64 confirmed COVID-19 cases reported between March 3 and April 26, 2022, was collected, and the epidemiological features were analyzed.

 We found COVID-19 epidemic caused by Omicron subvariant BA.2 in 2022 had unique characteristics compared to the earliest COVID-19 outbreaks in 2020 in Wuhu city. First, the geographic distribution of COVID-19 cases was highly concentrated, and most infections (58/64, 90.62%) were identified in one district in this study. Second, the mean age of COVID-19 cases in this study was 39.57 ± 16.39 years old, which was younger than the COVID-19 cases identified in Wuhan and Wuhu cities in 2020. Third, the spanned period of the COVID-19 outbreak in this study was shorter than the COVID-19 outbreak in 2020 in Wuhu city (13 days vs. 34 days).

 This study illustrates the epidemic of COVID-19 in Wuhu city from March to April 2022, and our result provides valuable information about COVID-19 outbreak caused by omicron subvariant BA.2. It also provides insights into developing effective strategies, such as high coverage of COVID-19 vaccination, lockdown policies, Ankang code, and population-bases COVID-19 screening, for successfully controlling the potential outbreaks caused by Omicron or future novel variants of SARS-CoV-2 in the medium-sized city like Wuhu.

 Acinetobacter baumannii is an important cause of nosocomial pneumonia in patients requiring long-term mechanical ventilation. Besides, extensively drug-resistant (XDR) strains cause infection in intensive care unit (ICU) patients. Chronic infections of A. baumannii and antimicrobial resistance are associated with biofilm formation. Several virulence genes, such as blaPER-1, pgaA, and bap, are involved in biofilm formation.

 The current study examines the expression levels of biofilm formation-related genes in pneumonia patients.

 The sputum samples were collected from patients hospitalized in the ICU, and A. baumannii ATCC 19606, the reference strain, was isolated and cultured on blood agar, eosin methylene blue agar, and chocolate agar medium. The media were then incubated at 37°C for 18 - 24 hours. Next, Gram-Thirty XDR A. baumannii isolates were collected from the sputum samples of ICU patients at Besat Hospital in Tehran, Iran. Bacterial isolates were characterized for antibiotic resistance patterns and biofilm-forming ability. Subsequently, RNA was extracted from the biofilm-forming isolates. A real-time polymerase chain reaction (PCR) assay was performed to evaluate the expression levels of the blaPER-1, pgaA, and bap genes. Transcripts were normalized to 16S rRNA as an internal control, and gene expression fold changes were calculated. Statistical analysis was performed using an unpaired two-tailed t-test (P < 0.05) with SPSS (V. 16).

 The disk diffusion susceptibility test revealed that all 30 (100%) isolates were resistant to piperacillin-tazobactam, cefepime, ceftriaxone, ceftazidime, gentamicin, imipenem, meropenem, levofloxacin, and ciprofloxacin. All 30 isolates from ICU-admitted patients (100%) were classified as XDR, and 27 (90%) isolates demonstrated the ability to form biofilms. The obtained results indicated a significant difference in gene expression levels. The fold change in expression for blaPER-1, bap, and pgaA was 7.473, 11.964, and 5.277, respectively.

 In our study, XDR A. baumannii primarily caused ventilator-associated pneumonia, and an observed increase in the expression of biofilm-related genes was noted in these strains. Healthcare centers should implement appropriate infection control programs to manage nosocomial infections, particularly in the ICU.

 Viral infections are the most common cause of fever and neutropenia in children without underlying disease, and data are still limited in this regard.

 This study aimed to identify the most common viral causes of fever and neutropenia in pediatrics.

 This descriptive-analytical study was conducted on pediatric patients younger than 18 years old referred to the pediatric emergency ward with fever as the chief complaint and no underlying diseases; patients with neutropenia and no evidence of bacterial infections in terms of different cultures were included in the study. After obtaining parental consent, nasopharyngeal swab specimens were taken from patients during the coronavirus disease 2019 (COVID-19) pandemic, and blood samples were analyzed to detect viruses in each patient.

 Fifty patients (54.3%) had mild neutropenia (absolute neutrophil count (ANC): 1000 - 1500/μL), 40 patients (43.5%) had moderate neutropenia (ANC: 1000 - 500/μL), and 2 cases (2.2%) had severe neutropenia (ANC < 500/μL). Among all the cases, 19 cases were positive in terms of virus examination, including adenovirus (6.5%), enterovirus (5.4%), cytomegalovirus (CMV) (3.3%), Epstein-Barr virus (EBV) (3.3%), and Herpes virus 6 (2.2%). A significant correlation was found between enterovirus and neutropenia (P = 0.005).

 The most common viruses found in neutropenic children hospitalized due to fever without any underlying disease were adenovirus and enterovirus, respectively. Considering the good general condition and relatively quick recovery, consideration of viral causes is recommended in this category of patients, and it is better to avoid prescribing broad-spectrum antibiotics, and careful follow-up should be carried out.