Avicenna Journal of Clinical Microbiology and Infection
Volume:9 Issue: 2, Jun 2022

Ventilator-associated pneumonia (VAP) is the second most common infection acquired in the intensive care unit (ICU). Bacteriological profiles cause VAP and their susceptibility patterns vary in different institutions.

A prospective study was conducted from June 2017 to May 2018 in a tertiary care hospital as per the recent NHSN guidelines in finding the incidence of VAP and further determining the etiological agents by both conventional and automated methods. The combination disk method (Phenotypic confirmatory test), ampicillin C (AmpC) disk test, modified carbapenem inactivation method, imipenem/ethylenediamine tetraacetic acid combined disc test, and cefoxitin disk test were performed for the detection of extended-spectrum beta-lactamases (ESBL), AmpC β-lactamases, carbapenemases, metallo-beta-lactamases (MBL), and methicillin-resistant Staphylococcus aureus, respectively.

Among 104 patients, 31 cases developed PVAP (possible VAP) during their ICU stay; of these cases, two patients had two episodes of VAP each, and the incidence of VAP was 32%. The most common isolate was Acinetobacter baumannii (38%), followed by Pseudomonas aeruginosa (22%), Klebsiella pneumoniae (16%), and Escherichia coli (13.51%). Twenty (54%) of the 37 VAP pathogens were multidrug resistant. ESBL was produced by 40% and 67% of E. coli and K. pneumoniae, respectively. MBL was produced by 25% of P. aeruginosa. In addition, AmpC beta-lactamases were produced by 18% each of the Enterobacteriaceae and non-fermenters, respectively. One of the two S. aureus isolates was methicillin-resistant.

The majority of VAP cases in our setting were caused by highly resistant strains. The frequency of specific multidrug resistance pathogens causing VAP may vary due to hospital, patient population, exposure to antibiotics, type of ICU patients, and changes over time, emphasizing the need for timely local surveillance data.

Helicobacter pylori (H. pylori) is identified as the most frequent agent of bacterial infections in humans which can cause various gastrointestinal diseases. This pathogen has infected approximately half of the world’s population, and its outbreak has varied across different regions. The purpose of this study was to estimate the H. pylori infection prevalence amongst patients in Fardis county, Alborz province, Iran, using noninvasive methods.

A total of 5677 patients were analyzed from September 2020 to October 2021 to detect H. pylori by the use of enzyme-linked immunosorbent assay (ELISA) IgG, IgA, and IgM tests, stool antigen test (SAT), and urea breath test (UBT).

Of 5677 patients, 3486 (61.4%) were female and 2191 (38.6%) were male with the mean age of 38.82 ± 18.289 years old. The overall rate of H. pylori infection positive was 31.46%, and the serological tests were the most prescribed types of tests. The IgG test and then SAT detected the most positive cases. Further, the infection rate was significantly associated with age. Except for the case of IgM, which was higher in females compared to males, no significant difference was found between gender and bacteria outbreak.

This study indicated a decline in H. pylori infection prevalence compared with the prior survey conducted at this center. However, its rate amongst the patients referring to Fardis laboratory is still high.

Nosocomial infection is an infection that hospitalized patients get while receiving health care. This study aimed to determine the prevalence and factors involved in the incidence of nosocomial infections, related microbial agents, and antibiotic resistance profiles.

This cross-sectional study was conducted on 390 patients with nosocomial infection admitted to Shahid Beheshti Hospital in Sabzevar from 2011 to 2015. The acquired data were assessed by the standard checklist of the National Nosocomial Infections Surveillance (NNIS) system of the Ministry of Health. The collected data were analyzed using the Stata 12 software.

Of the 41979 admitted patients during the mentioned period, 390 patients with an average age of 48.08 years suffered from a hospital-acquired infection. The prevalence of nosocomial infections was 1% with the highest rate related to the respiratory tract in men and surgical sites in women. Intravenous catheters, surgical wounds, urinary catheters, suction, ventilator, tracheotomy, and tracheostomy were the most commonly encountered factors (invasive measures) of nosocomial infection, respectively. The most prevalent causes of nosocomial infections were Klebsiella, Staphylococcus aureus, and Acinetobacter.

Based on our findings, several factors play a pivotal role in preventing hospital-associated infections, including proper follow-up and timely reporting of nosocomial infection cases. The other influential factors were accurate identification of microorganisms involved, allocation of sufficient funds to provide appropriate facilities for infection prevention, the appropriate and timely medical interventions, and the rational use of antibiotics.

The patients in the intensive care unit (ICU) are more susceptible to healthcare-associated infections (HAI). Higher rates of nosocomial infections in ICU patients are associated with higher morbidity, mortality, and costs. The primary outcome of our study was to investigate the relationship between antibiotic resistance and mortality in ICU patients, and the secondary outcome was to evaluate the relationship between antibiotic resistance and the length of ICU or hospital stay.

A 5-year observational retrospective study was conducted on patients in the ICU of Hasheminejad Kidney Center affiliated with Iran University of Medical Sciences, Tehran, Iran from January 1, 2015, to January 1, 2020. The data related to age, gender, admission type, comorbidities, length of ICU stay, length of hospital stay, infection source, microorganism type, and resistance pattern of all isolates and outcomes were collected based on the study purpose.

During the 5-year study, 2899 patients were admitted to the ICU, but only 747 patients were enrolled in the study, including 426 males (57%). The median age was 65 years (19-97 years). The mean length of ICU stay was greater in culture-positive patients (8.42 vs. 3.5 days, P>0.001). Culture-positive patients had significantly higher mortality compared to culture-negative patients (63.8% vs. 36.2%, P>0.001). In our study, it was found that resistant microorganisms have increased mortality by 2.6 times in the ICU in the crude model (OR: 2.6, P>0.001).

The findings of our study suggest that multidrug-resistant pathogens increase ICU stay and mortality.

Micro-RNAs (miRs) play several roles during infections with viruses. Therefore, the roles of miR21 and mir155 in the induction of the viral-related cancers have been the focus of attention in several studies. High risk human papilloma viruses (HPVs) are the main factors negatively contributing to the induction of HPV-related cancers. This study aimed to evaluate the expression of miR21 and mir155 in the patients with HPV-high risk genotypes in order to explore the roles of the miRs in the induction of HPV-related cancers.

In this study, 40 women infected with the high-risk HPV genotypes as well as 40 healthy controls were examined regarding the relative expression of miR21 and mir155 by adopting real-time polymerase chain reaction (PCR) technique. U6 was used for data normalization of miRNAs.

Relative expressions of both miR21 and miR155 were significantly higher in the HPV-infected patients compared to those in non-infected women.

It was concluded that miR21 and miR155 may have played key roles in the induction of HPV-related cancers among Iranian patients.

Seroprevalence among health care workers (HCWs) has been estimated in different studies in various regions and countries. This study aimed to screen the immunoglobulin M (IgM) and IgG seroprevalences and to assess the durability of IgG seropositivity, as well as the incidence of subsequent severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in a group of Iranian HCWs.

This voluntary serological screening was prospectively performed on 800 HCWs (492 females and 308 males) in Hamadan between November 2020 and February 2021. Anti-SARS-CoV-2 IgG and IgM antibodies were assessed by the enzyme-linked immunosorbent assay method at two-time intervals.

Overall, 243 out of 800 (30.38%) and 66 (8.25%) cases were IgG and IgM seropositive at their first antibody assessment, respectively. The male staff had a higher seroprevalence than females (31.49% vs. 29.67% for IgG, P=0.59 and 10.39% vs. 6.91% for IgM, P=0.08). Higher prevalences for both antibodies were found in the age group of 30-39.9 years (P=0.12 and P=0.05, respectively). In the second antibody screening, 81 (56.6%) cases were IgG seropositive. The mean titer of the first IgG antibody assessment in seropositive cases was lower than that of the second titer (2.95±2.07 vs. 5.08±4.01 cut-off index (COI) , P=1.4×10-5 ). Moreover, the comparison of the first and second IgG titers among 81 seropositive cases demonstrated a significantly increased level of anti-SARS-CoV-2 antibody (5.08±4.01 vs. 3.49±2.41 COI, P=0.002).

Our findings revealed that the mean level of the anti-SARS-CoV-2 IgG antibody was significantly increased in the seropositive individuals after 2 months of follow-up.

Microbial forensics is a multidisciplinary area, which has been recently considered an effective tool in forensic investigations. This growing field of forensics covers a wide spectrum of different branches of science, including biology, chemistry, physics, geology, mathematics, and computer sciences, leading to a practical approach that can be applied in several areas such as bioterrorist actions, environmental issues, emerging and reemerging diseases, as well as reliable trace evidence at a crime scene.

The information has been gathered via Google Scholar using several keywords, including forensic microbiology, bioterrorism, forensic investigation, and trace evidence. The data were from reliable articles and books published over 50 years. This paper is a short review of forensic microbiology with a bioinformatics perspective to use in different fields such as the court.

It is known that using either microorganisms or their toxins is a low-cost potential tool with serious morbidity and mortality rates that can spread all around the world by food or water supplies or even through the air, making them a perfect candidate bioweapon with minimum traceability. Studies have indicated that environmental conditions plus biological and abiotic factors would affect the following analysis and the final validation, which is an essential step in the forensic investigation due to its highly effective role in the court vote. To face different challenges, law enforcement has the infrastructure for attribution and deterrence (e.g., following the exact microbial forensics program) so that it can be used in court. Developing more reproducible, sensitive, and accurate methods, preparing a wide reliable database, and devoting the right amount of budget will help improve the whole forensic procedure in the legal system.

The current paper is a short review of how forensic scientists can use microbial features on a crime scene to clarify and enhance the procedure to solve different criminal cases.