mahmood saffari

Klebsiella pneumoniae is the common cause of pneumonia in hospitalized patients, particularly in intensive care units (ICU). The infection can transfer by medical equipment such as mechanical ventilators. This study aimed to investigate the molecular typing of the extended-spectrum beta-lactamase-producing K. pneumoniae isolates recovered from Beheshti Hospital, Kashan, Iran. 

K. pneumoniae isolates producing ESBLs have been collected from the samples obtained from Shahid Beheshti hospital, Kashan, Iran. Antimicrobial susceptibility was determined using the Kirby Bauer disk diffusion method. The presence of ESBLs was evaluated using CLSI for ESBL screening by the double-disk diffusion method. Molecular typing was conducted by pulsed-field gel electrophoresis (PFGE).  In total, 89 K. pneumoniae isolates were recovered, of which 47.1% were ESBL producers.

Results showed that all of the clinical and environmental isolates were resistant to ceftriaxone, meropenem, cefazolin, cefotaxime, cephalothin, and piperacillin-tazobactam. All isolates were grouped under four clusters (A-D). The major cluster was related to the C cluster with 22 isolates (19 clinical and 3 environmental). Seventy-two percent of isolates were from the ICU ward. There was no correlation between antibiotic resistance patterns and PFGE clusters (P=0.2).

We observed a common molecular signature among both clinical and environmental K. pneumoniae isolates, indicating a similar genotype and likely a common origin for ESBL producer isolates found in different hospital wards. Therefore, hospitals need to implement an effective infection control system to decrease the spreading of ESBL strains within the hospitals and subsequently the transmission of the infection to patients.

Increased prevalence of methicillin-resistant Staphylococcus aureus (MRSA) and treatment of infections due to these resistant strains is one of the most important health challenges. In this study, antimicrobial resistance patterns of Staphylococcus aureus isolates from patients were determined to commonly prescribed and last-resort antibiotics, and methicillin-resistant Staphylococcus aureus strains were isolated according to detection of mecA and femA genes.

This research was done on 146 Staphylococcus aureus isolates from hospitalized and outpatients who referred to Isfahan Hospitals and Shahid-Beheshti Hospital of Kashan from June 2017 to September 2018. Antimicrobial resistance patterns to common antibiotics were determined by disk diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) 2018 guidelines. Also Vancomycin minimum inhibitory concentration (MIC) of MRSA strains was determined using broth microdilution method. Isolation of MRSA strains were phenotypically done using cefoxitin disk and for confirmation mecA and femA genes were detected in these strains.

From 146 collected clinical samples, frequencies of MRSA and methicillin-susceptible Staphylococcus aureus (MSSA) were 24 (16.4%) and 122 (83.6%) respectively. The most resistance rate were detected to erythromycin 44 (30.1%) and vancomycin resistance was not seen among the S. aureus isolates, whereas linezolid resistance was 2/1 percent. In molecular study using PCR method, all MRSA strains carried mecA and femA genes.

Current study showed that the frequency of MRSA among clinical samples isolated from Isfahan and Kashan Hospitals is relatively high. Also the presence of resistance to new and important antibiotics as last resort treatment is considered a serious alarm.

Acute and chronic cholecystitis and cholangitis are common cases in general surgical diseases. Considering the role of infections in pathogenesis of these diseases, prescribing appropriate antibiotics is important to control the biliary tract infections. The aim of this study was to recognize the biliary pathogens as well as evaluate their antibiotic susceptibility in cholecystectomized patients.

This cross-sectional study was performed on 288 cholecystectomized patients with acute and chronic cholecystitis and cholangitis. During the operation, a sterile bile sample was aspirated from the gallbladder which was sent to the laboratory for culture and antibiogram evaluation.

Sixty-two (21.5%) patients were positive for bile culture. There were more positive cultures in cholangitis cases (64.7%) than the acute and chronic cholecystitis (22.8%, 12.2%, respectively; P=0.001). Thirty-six isolated pathogens were E.coli (58%) and 8 Klebsiella (12.9%). Moreover, the most effective antibiotics against the gram-negative bacteria: imipenem (100%), amikacin (98.1%) and gentamicin (90.4%) and for gram-positive bacteria: imipenem, vancomycin, rifampcin and clindamycin.

The third-generation cephalosporins, as an empirical treatment for biliary tract infections, lack the effective antibiotic susceptibility. Considering the high susceptibility (more than 90%) and the reasonable price of amikacin and gentamicin, cephalosporins are recommended as the first line treatment for biliary tract infection. Imipenem, an expensive broad-spectrum antibiotic, is not recommended as the first line treatment to avoid drug resistance.

Considering the importance of chemical and physical parameters such as temperature, moisture, pH and carbon to nitrogen (C:N) ratio in producing compost, the purpose of this study was aimed to evaluate these parameters in producing compost by stack method.

This descriptive study was carried out on municipal solid waste generated in Kashan during a 63-day period from Oct 3 to Dec 4, 2010. Compost samples were taken from the top one-third, the center and also the bottom of the compost pile and mixed; the compost pile was aerated (if necessary). Thereafter, samples were analyzed for carbon and nitrogen content using Fourti method.

The initial temperature of the compost pile was 38°C and then increased to 65°C at the 9th day, and reached to 26°C at the last day of composting. The moisture at the beginning of the process was 67.5%, increased to 73% at the 5th day and decreased to 38% at the last day. The initial pH of the compost was 5.5, increased during the compost process, and reached an optimal value of 7.7 at the end of the process. The C:N ratio at the beginning of the process was 35:1 and in mature compost decreased to 12.5:1.

Presence of actinomycetes and the dark-brown color of the prepared compost on the 63rd day of composting indicate that the compost meets the required standards. Consequently, the implementation of this method is suitable for tropical cities like Kashan.