فهرست مطالب
Infection, Epidemiology And Medicine
Volume:6 Issue: 2, Spring 2020
- تاریخ انتشار: 1399/03/13
- تعداد عناوین: 7
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Pages 85-93Aims
Burn infections are one of the most common causes of mortality in the world. On the other hand, microbial resistance to antibiotics has caused concern in the medical community. Therefore, controlling burn infections is very important, and using alternative therapies instead of antibiotics could be a good solution to this problem.
Materials & MethodsLactobacillus plantarum 299v strains were used in the experiments. Fifty male Wistar rats were prepared, and burn was induced in animals. The burn wounds were inoculated with clinical strains of MDR Pseudomonas aeruginosa in all animals and then treated daily with an eucerin ointment containing different compositions, including NaCl, imipenem, probiotic cell pellet, probiotic supernatant, and probiotic cell pellet + probiotic supernatant. The wound healing process was evaluated in animals after 7 days of treatment. Comparisons between different groups were performed using One-way ANOVA and Turkey’s post hoc tests.
FindingsAfter 7 days of treatment, the mean wound size in the probiotic cell pellet group was significantly lower than in the control and imipenem groups. Also, the mean wound size in the probiotic supernatant group was significantly lower than in the imipenem group. Histological parameters related to skin repair in the probiotic cell pellet group was better than in the control and antibiotic groups. Also, inflammation in the probiotic cell pellet group was less than in the control and imipenem groups.
ConclusionThe macroscopic results of this study supported the microscopic results and showed that the mean size of the burn wounds in the probiotic cell pellet group was less than in the control and imipenem groups after 7 days of treatment.
Keywords: Lactobacillus plantarum, Imipenem, Wound healing, Burn -
Pages 95-107Aim
Cereals and cereal-based products are prone to be infected by mycotoxin-producing fungi. The aim of this study was to investigate the level of contamination caused by 11 major mycotoxins in wheat samples collected from wheat silos in Tehran and Alborz provinces using UHPLC-MS/MS device.
Materials & MethodsSamples preparation was performed based on the extraction and purification procedures using acetonitrile/water/acetic acid solvents and Myco6in1 immunoaffinity columns, respectively. Selected mycotoxins were detected simultaneously using reversed phase ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) with electrospray ionization technique in positive-ion mode in a 15-minute run in the MRM program. Spiked samples calibration curve was used to overcome the matrix effects and to determine the residual mycotoxins.
FindingsQuantification and detection limits for AFB1 and OTA mycotoxins were 2 and 0.7 ppb; for DON, FB1, and FB2 were 100 and 33.3 ppb; for ZER were 50 and 16.6 ppb: for AFB2, AFG1, AFG2, and T-2 were 5 and 1.6 ppb; and for HT-2 were 20 and 6.6 ppb, respectively. Good precision and linearity was observed for mycotoxins. The average recovery rate of mycotoxins was in the range of 72-123 %, and the relative standard deviation (RSDr), indicating the method accuracy, was between 0.6-24.2 %. The validated method for analyzing the 30 wheat samples was used to evaluate the residual mycotoxins. OTA, T-2, and HT-2 mycotoxins were found in wheat samples. Only in one sample, the level of residual OTA exceeded the allowable limit set by the Iranian National Standards Organization.
ConclusionThe present study results highlighted the need for monitoring wheat and wheat-based products and the implementation of control and preventive measures in wheat fields, storage warehouses, and flour factories.
Keywords: Mycotoxins, Wheat, UHPLC-MS, MS, Myco6in1 -
Pages 109-116Aims
Acinetobacter baumannii is an opportunistic pathogen that is resistant to many antibiotics including beta-lactams. Production of β-lactamases is the main mechanism of β-lactam resistance in A. baumannii strains. The aim of this study was to determine the frequency of blaTEM and blaVEB genes in clinical isolates of A. baumannii and the relationship between the antibiotic resistance and the presence of ESBL genes in strains isolated from burn wound infection in Isfahan.
Materials & MethodsIn this study, 123 MDR A. baumannii strains were isolated from burn wound infection. After antibiotic resistance evaluation using the Kirby-Bauer disc-diffusion method, all the isolates were evaluated with polymerase chain reaction (PCR) technique to detect ESBL genes, followed by statistical analysis by the end.
FindingsOut of 123 A. baumannii isolates, 77 (62.60%) strains were ESBL positive according to the PCR results. The frequency of blaTEM and blaVEB genes was 52 (42.3%) and 67 (54.5%), respectively. There was a significant relationship between the antibiotic resistance and the presence of ESBL genes (blaTEM and blaVEB) in A. baumannii strains.
ConclusionThe high prevalence of blaTEM and blaVEB genes in A. baumannii strains found in this study is the major concern about burn wound infections in Isfahan and Iran because of the complexity in treating infections caused by these strains. This study results highlighted the need for infection control measures to prevent the spread of resistant isolates and ESBL genes, especially in burn hospitals.
Keywords: Acinetobacter baumannii, Antibiotic resistance, blaTEM, blaVEB -
Pages 117-125Aims
This study aimed to determine the antibiotic resistance pattern of Pseudomonas aeruginosa clinical isolates and the frequency of blaSIM and blaAmpC genes in resistant strains.
Materials & MethodsIn this cross-sectional study, 94 P. aeruginosa isolates were collected from the burn wards of Gilan province hospitals in 2018 and identified by biochemical methods. Strains producing β-lactamases and metallo-β-lactamases were detected by two
methodsdisk diffusion method and antibiotic resistance method in combination with disk diffusion method, respectively. The presence of blaSIM and blaAmpC genes in the resistant strains was investigated using PCR, and data analysis was performed.
FindingsBased on the obtained results, colistin was identified as the most effective antibiotic with a resistance rate of 27.7%, and the highest antibiotic resistance was observed against trimethoprim/sulfomethoxazole (83%). In the phenotypic test of 94 samples, 29 (30.9%) carbapenemase-producing isolates and 33 (35.1%) β-lactamase-producing isolates were identified. Based on the PCR results, among 44 (46.8%) samples containing β-lactamase and carbapenemase enzymes, the frequency of blaSIM gene was 9.1% (4 of 44, and 4.3% in all the studied isolates), and the frequency of blaAmpC gene was 15.9% (7 of 44, and 7.4% in the all studied isolates).
ConclusionThe results of this study indicated a high prevalence of drug resistance in clinical isolates of P. aeruginosa. In particular, there was an increasing rate of resistance to beta-lactam antibiotics, and the presence of MBL and ESBL associated genes was considerable, which limit the choice of suitable treatment for patients with severe infections.
Keywords: Pseudomonas aeruginosa, Antibiotic resistance, PCR, blaSIM, blaAmpC -
Pages 127-134Aims
Numerous microbial agents have been identified as the causative agents of UTIs, such as Escherichia coli. The spread of antibiotic resistance is increasing among strains causing UTIs. The present study aimed to investigate the prevalence of etiological agents of UTIs and their antibiotic resistance patterns and to determine related risk factors and treatment outcomes of antibiotic resistance in Razi teaching hospital, Guilan, North of Iran.
Material & MethodsThis retrospective cross-sectional study was performed from April 2017 to September 2018. All patients with clinical symptoms of UTI were included. The patients’ complete medical records were assessed. Moreover, bacterial isolation and identification were performed by conventional bacteriological and standard biochemical tests. Antibiotic susceptibility testing was performed using the disk diffusion method based on the CLSI recommendation.
FindingsGram-negative bacilli were identified as the most common causative agents of UTIs in all cases (140, 100%), of which E. coli had the highest isolation rate with 76 cases (54.3%), followed by Klebsiella spp. with 23 cases (16.4%). Antibacterial susceptibility tests revealed that 64.3% of the isolates were resistant to three antibiotics of different classes (MDR phenotype).
ConclusionIn conclusion, Gram-negative bacilli were the most common causative agents of UTIs, and E. coli had the highest isolation rate (54.3%). Regarding the high prevalence of antibiotic resistance and MDR phenotype, paying attention to drug resistance patterns of pathogens and proper and correct administration of antibiotics as well as proper and timely monitoring of treatment, could help physicians decrease the patients’ mortality rate.
Keywords: Antibiotic resistance, Escherichia coli, Urinary tract infection, MDR -
Pages 135-141Aims
Infectious diseases are among the most serious diseases that may lead to death in many parts of the world. This study was conducted to investigate the main causes of mortality among patients hospitalized in the infectious ward and respiratory ICU of Sina hospital in Hamadan.
Materials & MethodsThe medical records of patients hospitalized from March 2012 to March 2017 in the infectious ward and respiratory ICU were investigated, those not surviving during the hospitalization.
FindingsA total of 593 medical records of patients were reviewed, of which 534 cases were enrolled in this study. Among which, 426 (79.8 %) and 108 (20.2%)cases were related to patients hospitalized in the respiratory ICU and infectious ward, respectively The mortality rate during 2012 to 2016 was calculated as follows: 4.69% in 2012, 6.31% in 2013, 4.68% in 2014, 5.2% in 2015, and 5.8% in 2016. This study results showed that the most common causes of mortality were sepsis (44.4%) in the respiratory ICU and pneumonia (25.3%) in the infectious ward. The highest rates of case fatality were related to sepsis (237cases, 48.2%) and pulmonary embolism (15 cases, 44.1%).
ConclusionsThe present study findings showed that sepsis and pneumonia were the most common causes of death among patients hospitalized in the infectious diseases ward and respiratory ICU; also, sepsis and pulmonary embolism accounted for the highest case fatality rates.
Keywords: Mortality, Infectious diseases, Sepsis, Intensive care unit -
Pages 143-151Aims
This study aimed to provide more information about the influence of Coronavirus Disease2019 (COVID-19) on infected individuals. The symptoms, conditions, and treatments used may be served as important clues to find out potential medications.
Materials & MethodsVarious current papers were reviewed, and the findings were summarized. In addition, other diseases such as severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), which have similar causes or symptoms in patients, were investigated.
FindingsThe most common symptoms in infected patients were fever (98%), dry cough (76%), and dyspnoea (55%). Mechanical ventilation was the main supportive treatment for ICU patients, and the mortality rate of patients with chronic diseases in the intensive care unit (ICU) was high (55%). The virus is highly contagious compared to the previous Betacoronaviruses causing epidemic, but its mortality rate is lower so that most of the infected patients studied had minor symptoms or were asymptomatic. Several treatments, such as antiviral agents and antimalarial drugs, are presently being proposed and tested, but none have yet been proven to be effective.
ConclusionsSeniors and patients with chronic diseases are at higher risk of COVID-19 induced severe consequences and mortality. Currently, supportive treatment is the mainstay for severely ill patients.
Keywords: COVID-19, Coronavirus, SARS, MERS