Molecular detection of carbapenem-resistant genes in clinical isolates of Klebsiella pneumoniae

INTRODUCTION

The emergence of carbapenem-resistant Klebsiella pneumoniae (CRKP) poses a considerable threat to public health worldwide. The aim of this study was to determine the prevalence of CRKP isolated from clinical specimens by phenotypic and genotypic methods.

METHODS

In total, 110 consecutive non-repetitive isolates of K. pneumoniae were analyzed. Minimal inhibitory concentrations (MICs) of imipenem were determined. The mechanism of resistance was evaluated by imipenem-EDTA combined disk test and modified Hodge test. PCR method was used for the detection of blaVIM, blaIMP, blaNDM-1, blaOXA-48 and KPC genes.

RESULTS

Totally, 8 (7.3 %) isolates were resistant to imipenem, showing MIC ≥4 µg/mL. Based on imipenem-EDTA combined disk test, all imipenem-resistant isolates were metallo-beta-lactamase (MBL) positive. PCR confirmed that 6 (75%) isolates were blaNDM-1 positive. Other resistance genes (blaVIM, blaIMP, blaOXA-48 and KPC) were not detected.

CONCLUSIONS

Based on this study, the prevalence of CRKP strains was not at a high level, however, continuous monitoring of antibiotic resistance should be performed to control dissemination of CRKP infections.

Antibiotic resistance profiles of Salmonella serotypes isolated from animals in Iran: a meta-analysis

BACKGROUND

Salmonella infection (salmonellosis) is a zoonotic bacterial disease. Widespread use of antibiotics in livestock and poultry production for different purposes such as treatment and growth promotion has led to the emergence of antibiotic-resistant Salmonella, causing treatment of Salmonella infections more difficult with each passing year.

AIMS

To determine the antibiotic resistance prevalence of Salmonella serotypes isolated from animals in different provinces of Iran.

METHODS

To find eligible articles, we searched the international and national electronic databases using appropriate keywords in English and Persian.

RESULTS

After applying predefined criteria, 54 articles reporting antibiotic resistance profiles of Salmonella serotypes were included. Salmonella isolates were mostly resistant against nalidixic acid (67%), tetracycline (66.9%), and streptomycin (49.6%), followed by trimethoprim/sulfamethoxazole (41.6%) and kanamycin (23.6%). The highest sensitivity was observed against imipenem, meropenem, and cefepime with 1.7%, 1.4%, and 1.9% of all isolates being resistant, respectively.

CONCLUSION

Results revealed that the prevalence of resistant isolates to nalidixic acid, tetracycline and streptomycin is high and their use must be restricted. In addition, resistance to other antibiotics such as chloramphenicol, ampicillin, cephalothin, cefixime, and enrofloxacin is at an alarming level that calls for attention in the future infection control and antibiotic stewardship programs.

A systematic review and meta-analysis on the epidemiology of antibiotic resistance of Vibrio cholerae in Iran

BACKGROUND

Cholera, an acute diarrheal disease caused by Vibrio cholerae (V. cholerae), is an endemic disease and a major public health problem in Iran. Antibiotic therapy can decrease duration of the disease, transmission of infection and contamination of the environment. Considering different pattern of V. cholerae antibiotic resistance around the world, the aim of the current systematic review and meta-analysis was to evaluate the prevalence of antibiotic resistance of V. cholerae in Iran.

METHODS

A systematic review of the literature was performed using related keywords in the electronic national and international databases including SID, Irandoc, Iran Medex and Magiran as well as PubMed, Scopus, Google Scholar and ISI web of knowledge. Up to July 31, 2018, 27 eligible papers were included in our meta-analysis based on the defined inclusion criteria.

RESULTS

V. cholerae O1 was the most prevalent strain isolated in Iran and exhibited a high resistance rate against numerous antibiotics including chloramphenicol (33.6%), oxytetracycline (40.2%), trimethoprim/sulphamethoxazole (86%), tetracycline (34.5%), furazolidone (69.8%), streptomycin (93.8%), polymyxin (80.7%), ampicillin (32.1%), nalidixic acid (88.9%), kanamycin (29%) and amoxicillin (30.5%).

CONCLUSIONS

According to the meta-analysis results, antibiotic therapy with ciprofloxacin, doxycycline, erythromycin, gentamicin, azithromycin, cefixime and cefepime could be effective for the treatment of severe cases of cholera in Iran.

An investigation on cardioprotective potential of Marrubium vulgare aqueous fraction against ischaemia-reperfusion injury in isolated rat heart

BACKGROUND

The aim of this study was to evaluate the cardioprotective effects of aqueous fraction of Marrubium vulgare hydroalcoholic extract on cardiac parameters in ischaemic-reperfused isolated rat hearts.

MATERIALS AND METHODS

The aerial parts of the plant were extracted with methanol 70% by maceration. The water-soluble portion of the total hydroalcoholic extract was prepared with liquid-liquid extraction (LLE). Afterwards, the antioxidant activity, total phenolic and flavonoids content of the aqueous fraction were determined. In order to evaluate the effects of the aqueous fraction on cardiac parameters and ischaemia-reperfusion (I/R) injury, the Langendroff method was used on male Wistar rats. Harvested hearts were cannulated immediately to the Langendroff apparatus and subjected into 30 min regional ischaemia and 2 h reperfusion, either by a modified Krebs-Henseleit buffer (KHB) solution or enriched KHB solution with plant extract (10, 20, 40 μg/mL).

RESULTS

The aqueous fraction was found to be a scavenger of DPPH radical with RC50 value of 47 μg/mL. The total phenolic and flavonoids content of the fraction was 6.05 g gallic acid equivalent and 36.13 mg quercetin equivalent per 100 g of dry plant material. In addition, 40 μg/mL of Marrubium vulgare aqueous fraction significantly decreased infarct size in comparison to control group. All doses considerably reduced the total ventricular ectopic beats during 30 min of ischaemia. The extract at dose of 40 μg/mL noticeably decreased the arrhythmias during the first 30 min of reperfusion.

CONCLUSIONS

The results of the study indicated aqueous fraction of Marrubium vulgare possesses a protective effect against I/R injuries in isolated rat hearts.