The role of comorbidities on mortality of COVID-19 in patients with diabetes.

BACKGROUND: Patients with diabetes are one of the most high-risk group to become infected with SARS-CoV-2. Current study was designed to evaluate the risk of other complications in COVID-19 patients with diabetes. METHODS: In this cross-sectional study (25 February to July 10, 2020), 458 patients with diabetes were enrolled based on their characteristics, symptoms and signs, laboratory data and presence of other underlying diseases. Multiple logistic regression and Chi-square test analysis were used to check the effectiveness of other comorbidities on the mortality outcome among patients with diabetes. RESULTS: Of 458 patients with diabetes, 306 (67%) had other underlying diseases, such as 200 (65.4%) hypertension, 103 (33.7%) cardiovascular diseases and 29 (9.5%) kidney diseases. The rate of fatality was significantly high in patients with chronic kidney and liver diseases. The odds of mortality were increased 3.1-fold for patients over 55 years as compared to those under 55 years (P = 0.011), and the odds of mortality outcome were more than 5.1-fold for those who had chronic kidney disease (P < 0.001). CONCLUSIONS: The presentation of SARS-CoV-2 in older patients with diabetes with other comorbidities such as chronic kidney and liver diseases is more severe in risk of mortality.

Investigation of carbapenem resistant Acinetobacter baumannii ST2 in Iran.

This study investigated carbapenem resistance among Acinetobacter baumannii isolated from respiratory specimens. Epidemiological relationship of the isolates was also evaluated. In this study, 81 respiratory specimens of A. baumannii from AL Zahra Hospital were confirmed by phenotypic and genotypic methods. Antimicrobial susceptibility was performed by disc diffusion method. Carbapenem resistance genes were identified by PCR. The isolates were typed by RAPD-PCR and multilocus sequence typing (MLST) methods. All isolates were resistant to imipenem and 80 isolates to meropenem. Frequency of oxacillinase genes was as follows: blaOXA-23 gene was positive in 74 (91.3%), blaOXA-24 gene in 50 (61.7%) and blaOXA-58 was not found in any isolates. On the other hand 22 (27.2%) isolates contained blaIMP-1, 3 (3.7%) isolates contained blaIMP-2 gene, 5 (6.2%) isolates contained blaVIM-1, 4 (5%) isolates had blaVIM-2 and none of the isolates had blaSIM-1 gene. RAPD-PCR typing identified 16 different patterns, with one pattern being the most frequent one in 26 isolates. In MLST 6 different sequence types were identified, the most predominant being ST2 belonging to clonal complex 2. The results of this study showed high resistance to carbapenems as well as high abundance of oxacillinase genes.

The emergence of blaOXA-48 and blaNDM among ESBL-producing Klebsiella pneumoniae in clinical isolates of a tertiary hospital in Iran.

The aim of this study was to investigate the prevalence of carbapenem-resistant Klebsiella pneumoniae (CRKP) and the most common types of carbapenemases, metallo-beta-lactamases (MBLs), and extended-spectrum beta-lactamases (ESBLs) among CRKP isolates in a tertiary hospital in Isfahan, Iran. Eighty non-repetitive clinical isolates of K. pneumoniae were obtained from different clinical specimens. Antibiotic resistance pattern of isolates was determined by disk diffusion method and production of carbapenemases and MBLs was confirmed using modified Hodge test and E-test, respectively. Molecular detection of the antibiotic resistance genes was performed using PCR. Fifty-one (63.8%) isolates have decreased susceptibility to carbapenems, of which 46 (90.2%) isolates were as carbapenemase producer and four (7.8%) isolates were positive for MBLs, phenotypically. The results of PCR showed that the prevalence of blaOXA-48, blaNDM, blaSHV, blaCTX-M, and blaTEM genes among CRKP isolates were 90.2%, 15.7%, 98%, 96.1%, and 90.2%, respectively. No isolates carrying the blaKPC, blaGES, blaIMI, blaVIM, and blaIMP genes were detected. This study showed that the production of OXA-48 is one of the main mechanisms of resistance to carbapenems in CRKP isolates in Isfahan. In addition, the dissemination of NDM-producing CRKP isolates is a potential risk for the health care system of this area in the near future.

Determination of antibiotic resistance pattern and prevalence of OXA-type carbapenemases among Acinetobacter baumannii clinical isolates from inpatients in Isfahan, central Iran.

Acinetobacter baumannii is one of the most important bacterial species with the ability to produce OXA-type carbapenemases. We aimed to evaluate the prevalence of OXA-type carbapenemases among clinical isolates of A. baumannii in three major hospitals of Isfahan. In this cross-sectional descriptive study, 153 non-repeated strains of A. baumannii were isolated from various clinical samples of hospitalized patients in Al-Zahra, Imam Mousa Kazem, and Shariati hospitals from October 2015 to October 2016. Antimicrobial susceptibility testing for imipenem, meropenem, ertapenem, cefepime, ceftazidime, ceftriaxone, piperacillin-tazobactam, gentamicin, amikacin, ciprofloxacin, and tetracycline was performed using the disk diffusion method. In order to identify bla-oxa genes, a multiplex polymerase chain reaction was used. The resistance rates in A. baumannii isolates to beta-lactam antibiotics including imipenem, ertapenem, meropenem, cefepime, ceftazidime, ceftriaxone, and piperacillin/tazobactam were 100%, 100%, 99.3%, 97.4%, 96.7%, 97.4%, and 98.6%, respectively. PCR assay showed the presence of bla-oxa genes in all isolates. The bla-oxa-51 gene was recognized in all (100%) isolates, 90.8% and 62.1% of isolates possessed the bla-oxa-23 and bla-oxa-24 genes, respectively, while the bla-oxa-58 gene was not detected in any of the isolates. Also, 56.2% of isolates had both the bla-oxa-23 and bla-oxa-24 genes simultaneously. We found that the prevalence of OXA-type carbapenemases among carbapenem-resistant A. baumannii isolates is high in Isfahan, with OXA-23 being the major carbapenemase mechanism responsible for the resistance phenotype.

Prevalence of CTX-M and TEM ß-lactamases in Klebsiella pneumoniae Isolates from Patients with Urinary Tract Infection, Al-Zahra Hospital, Isfahan, Iran.

BACKGROUND: Extended-spectrum ß-lactamase (ESBL)-producing is a significant resistant mechanism to ß-lactams in Enterobacteriaceae, especially in Klebsiella pneumoniae. The main objectives of this study were to genetically characterize urinary clinical isolates of K. pneumoniae through the investigating of blaTEM, blaCTX-M and using molecular typing by Enterobacterial repetitive intergenic consensus polymerase chain reaction (ERIC-PCR) method. We also determined the frequency of antibiotic resistance of K. pneumoniae strains to characterize the ß-lactamases included. MATERIALS AND METHODS: A cross-sectional study was carried out to evaluate 98 strains of K. pneumoniae isolated from urine culture of outpatients referred to Al-Zahra Hospital, Isfahan, Iran. Antibiotic susceptibility testing was performed using Kirby-Bauer's method. Screening of ESBLs was carried out using double-disk screening test. PCR technique was performed to detect TEM and CTX-M genes. The total DNA of each strain was tested by ERIC-PCR. RESULTS: In 98 K. pneumoniae studied clinical isolates, 25.5% were ESBL producing and 44.9% multidrug-resistant (MDR). From 25 ESBL isolates, 23 (92%) cases showed MDR phenotype. In ESBL producing isolates, 23 (92%) were blaCTX-M and 19 (76%) blaTEM positive. The antimicrobial drug susceptibilities of ESBL isolates indicated high resistant rates for cefotaxime and ceftazidime. All 25 ESBL producing isolates were resistant to cefotaxime. Complex patterns of fingerprints isolates showed that 36% of the isolates were belonged to the cluster no 5. CONCLUSION: This study revealed high antimicrobial resistance rates among ESBL isolates which can lead to various health difficulties. Epidemiological data collection from patients is recommended to develop the strategies to manage antibiotic resistance.

Investigation of Class I, II, and III Integrons Among Acinetobacter Baumannii Isolates from Hospitalized Patients in Isfahan, Iran.

OBJECTIVES: This study aimed to determine the prevalence of class I, II, and III integrons among clinical Acinetobacter baumannii isolates collected from hospitalized patients. METHODS: This cross-sectional study was conducted at two teaching hospitals in Isfahan, Iran, from October 2015 to October 2016. A total of 147 non-duplicate A. baumannii isolates were collected from clinical specimens and identified as A. baumannii using standard microbiological methods and confirmed by genotyping. Antimicrobial susceptibility was determined using disc diffusion method, and the presence of integron genes was performed using the polymerase chain reaction. RESULTS: Out of 147 confirmed A. baumannii isolates, 97.3% of isolates were extensive drug-resistant (XDR) and 2.7% were multidrug-resistant (MDR). Class I and II integrons were detected in 63.9% and 78.2% of the A. baumannii, respectively. Class III integron was not detected in any of the isolates. CONCLUSION: Our results show a high prevalence of classes I and II integrons which may play a key role in the acquisition of MDR and XDR phenotype among A. baumannii isolates in our region. Therefore, use of appropriate infection control in clinical settings and implementation of treatment strategies is necessary for our hospitals.

Comparison of stresses induced by fiber post, parapost and casting post in root canals by photoelasticity method.

INTRODUCTION: Many studies have been performed to evaluate the stress distribution around endodontic posts; those which compared posts composed of different materials are rare. The aim of this study was to compare stresses induced in dentin by three structurally different posts using photoelasticity method. MATERIALS AND METHODS: Nine blocks of PSM-5 Photoelastic material with 45×45×10 mm dimension were prepared. In each block, a canal 9 mm in length and 0.8 mm in width was drilled. Blocks were divided into 3 groups of three each. In the first group, the canals were prepared for insertion of Fiber Post with 1.25 mm width. In the second group, the canals were prepared for insertion of ParaPost with 1.25 mm width and the canals in the third group were prepared for casting post similar to the above samples. Casting Post pattern was made by Duralay resin and casted by Ni-Cr alloy. All posts were cemented in canals with Panavia cement. The stresses were evaluated in the polariscope under three different conditions: 1) without load, 2) with 135 N vertical load, and 3) with 90 N oblique load (26° inclination to post long axis). The fringe orders in the cervical, middle and apical regions of the posts were evaluated and compared with each other. RESULTS: Application of the vertical load induced a high stress concentration (FO=4) in the apical region of the ParaPost, while lower stress was observed in the middle (FO=2) and cervical region (FO=2+). Fiber Post and Casting Post showed even stress distribution (FO=2+). High stress concentration was detected with the application of oblique force in the cervical region of ParaPost (FO=5) and Casting Post (FO=3+). Fiber Posts fractured before reaching 90-N loading force. CONCLUSION: The stress distribution around Fiber Post and Casting Post were constant in comparison with ParaPost. Fiber Post with 1.25 mm width was not recommended in situations with high oblique stresses.

Multiple in vitro analyses of fracture resistance in maxillary central incisors restored with fiber posts.

INTRODUCTION: The resistance to fracture of endodontically treated teeth restored with esthetic post systems has not been extensively researched. This in vitro study compared the fracture patterns of endodontically treated teeth with esthetic post systems with different analysis methods. MATERIALS AND METHODS: A total of 26 recently extracted human maxillary central incisors were decoronated and then endodontically treated. Teeth were restored with quartz fiber posts. All posts were cemented with Panavia dual curing adhesive resin cement and subsequently restored with composite cores. Three methods were used to test fracture resistance. Each specimen was embedded in acrylic resin and then secured in a universal load-testing machine. A compressive load was applied at 135º degree angle at a crosshead speed of 1 mm/min to the long axis of the tooth until fracture occurred. The two other methods, finite element analysis (FEA) and photo elastic study used the same angulation and 90 N force to simulate the first method. The data were then compared. RESULTS: Clinical results indicated that fracture was most likely to occur between core and dentin, and then in the cervical 1/3 of the root. Photo elastic study demonstrated similar results; the highest stresses occurred at the junction of dentin and core contralateral to the side where force was applied. FEA also confirmed these results; however it also showed that the highest stresses arise at the dentin/core junction contralateral to the force point. CONCLUSION: All three techniques reiterate that the risk of fracture is greatest at the cervical dentin/core junction.